src/Makefile

@@ -1,28 +1,47 @@
 
 uname_S := $(shell sh -c 'uname -s 2>/dev/null || echo not')
 
+TARGET_NAME=redis-migrate.so
 WARN=-Wall -W -Wno-missing-field-initializers
+NODEPS:=clean
 # Compile flags for linux / osx
 ifeq ($(uname_S),Linux)
-	SHOBJ_CFLAGS ?= -W -Wall -fno-common -g -ggdb -std=c11 -O2 $(WARN) $(OPTIMIZATION)
+	SHOBJ_CFLAGS ?= -W -Wall -fno-common -fPIC $(DEBUG) -std=gnu99 -O2 $(WARN) $(OPTIMIZATION)
 	SHOBJ_LDFLAGS ?= -shared
 else
-	SHOBJ_CFLAGS ?= -W -Wall -dynamic -fno-common -g -ggdb -std=c11 -O2 $(WARN) $(OPTIMIZATION)
+	SHOBJ_CFLAGS ?= -W -Wall -dynamic -fno-common -fPIC $(DEBUG) -std=gnu99 -O2 $(WARN) $(OPTIMIZATION)
 	SHOBJ_LDFLAGS ?= -bundle -undefined dynamic_lookup
 endif
 
+FINAL_CFLAGS+= -I./hiredis $(SHOBJ_CFLAGS)
+
+.PHONY: all
+
 .SUFFIXES: .c .so .xo .o
 
+all: $(TARGET_NAME)
+	@echo ""
+	@echo "Hint: build redis-migrate success ;)"
+	@echo ""
 
 .c.xo:
-	$(CC) -I. $(CFLAGS) $(SHOBJ_CFLAGS) -fPIC -c $< -o $@
+	$(CC) -I. $(CFLAGS) $(FINAL_CFLAGS) -fPIC -c $< -o $@
 
-all: redis-migrate.so
+sds.xo: fmacros.h sds.h sdsalloc.h
+ssl.xo: hiredis.h async.h
+async.xo: fmacros.h alloc.h net.h sds.h async.h
+net.xo: fmacros.h net.h sds.h
+ae.xo: ae.h hiredis.h async.h
+read.xo: fmacros.h alloc.h sds.h
+alloc.xo: fmacros.h alloc.h
+dict.xo: fmacros.h alloc.h dict.h
+ae.xo: redismodule.h
+hiredis.xo:fmacros.h hiredis.h net.h sds.h alloc.h async.h
+redis-migrate.xo: redismodule.h
 
+XO_LIBS=redis-migrate.xo hiredis.xo sds.xo ssl.xo read.xo alloc.xo dict.xo async.xo net.xo ae.xo
 
-redis-migrate.xo: ./redismodule.h
-
-redis-migrate.so: redis-migrate.xo
+redis-migrate.so: $(XO_LIBS)
 	$(LD) -o $@ $^ $(SHOBJ_LDFLAGS) $(LIBS) -lc
 
 clean:

src/ae.c

@@ -0,0 +1,502 @@
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/epoll.h>
+#include <fcntl.h>
+#include "ae.h"
+
+
+void redisAeReadEvent(aeEventLoop *el, int fd, void *privdata, int mask) {
+    ((void)el); ((void)fd); ((void)mask);
+
+    redisAeEvents *e = (redisAeEvents*)privdata;
+    redisAsyncHandleRead(e->context);
+}
+
+void aeStop(aeEventLoop *eventLoop) {
+    eventLoop->stop = 1;
+}
+
+void aeMain(aeEventLoop *eventLoop) {
+    eventLoop->stop = 0;
+    while (!eventLoop->stop) {
+        aeProcessEvents(eventLoop, AE_ALL_EVENTS|
+                                   AE_CALL_BEFORE_SLEEP|
+                                   AE_CALL_AFTER_SLEEP);
+    }
+}
+
+monotime (*getMonotonicUs)(void) = NULL;
+
+/* Process time events */
+static int processTimeEvents(aeEventLoop *eventLoop) {
+    int processed = 0;
+    aeTimeEvent *te;
+    long long maxId;
+
+    te = eventLoop->timeEventHead;
+    maxId = eventLoop->timeEventNextId-1;
+    monotime now = getMonotonicUs();
+    while(te) {
+        long long id;
+
+        /* Remove events scheduled for deletion. */
+        if (te->id == AE_DELETED_EVENT_ID) {
+            aeTimeEvent *next = te->next;
+            /* If a reference exists for this timer event,
+             * don't free it. This is currently incremented
+             * for recursive timerProc calls */
+            if (te->refcount) {
+                te = next;
+                continue;
+            }
+            if (te->prev)
+                te->prev->next = te->next;
+            else
+                eventLoop->timeEventHead = te->next;
+            if (te->next)
+                te->next->prev = te->prev;
+            if (te->finalizerProc) {
+                te->finalizerProc(eventLoop, te->clientData);
+                now = getMonotonicUs();
+            }
+            hi_free(te);
+            te = next;
+            continue;
+        }
+
+        /* Make sure we don't process time events created by time events in
+         * this iteration. Note that this check is currently useless: we always
+         * add new timers on the head, however if we change the implementation
+         * detail, this check may be useful again: we keep it here for future
+         * defense. */
+        if (te->id > maxId) {
+            te = te->next;
+            continue;
+        }
+
+        if (te->when <= now) {
+            int retval;
+
+            id = te->id;
+            te->refcount++;
+            retval = te->timeProc(eventLoop, id, te->clientData);
+            te->refcount--;
+            processed++;
+            now = getMonotonicUs();
+            if (retval != AE_NOMORE) {
+                te->when = now + retval * 1000;
+            } else {
+                te->id = AE_DELETED_EVENT_ID;
+            }
+        }
+        te = te->next;
+    }
+    return processed;
+}
+
+static int aeApiPoll(aeEventLoop *eventLoop, struct timeval *tvp) {
+    aeApiState *state = eventLoop->apidata;
+    int retval, numevents = 0;
+
+    retval = epoll_wait(state->epfd,state->events,eventLoop->setsize,
+                        tvp ? (tvp->tv_sec*1000 + (tvp->tv_usec + 999)/1000) : -1);
+    if (retval > 0) {
+        int j;
+
+        numevents = retval;
+        for (j = 0; j < numevents; j++) {
+            int mask = 0;
+            struct epoll_event *e = state->events+j;
+
+            if (e->events & EPOLLIN) mask |= AE_READABLE;
+            if (e->events & EPOLLOUT) mask |= AE_WRITABLE;
+            if (e->events & EPOLLERR) mask |= AE_WRITABLE|AE_READABLE;
+            if (e->events & EPOLLHUP) mask |= AE_WRITABLE|AE_READABLE;
+            eventLoop->fired[j].fd = e->data.fd;
+            eventLoop->fired[j].mask = mask;
+        }
+    } else if (retval == -1 && errno != EINTR) {
+        //panic("aeApiPoll: epoll_wait, %s", strerror(errno));
+    }
+
+    return numevents;
+}
+
+static int64_t usUntilEarliestTimer(aeEventLoop *eventLoop) {
+    aeTimeEvent *te = eventLoop->timeEventHead;
+    if (te == NULL) return -1;
+
+    aeTimeEvent *earliest = NULL;
+    while (te) {
+        if (!earliest || te->when < earliest->when)
+            earliest = te;
+        te = te->next;
+    }
+
+    monotime now = getMonotonicUs();
+    return (now >= earliest->when) ? 0 : earliest->when - now;
+}
+
+/* Process every pending time event, then every pending file event
+ * (that may be registered by time event callbacks just processed).
+ * Without special flags the function sleeps until some file event
+ * fires, or when the next time event occurs (if any).
+ *
+ * If flags is 0, the function does nothing and returns.
+ * if flags has AE_ALL_EVENTS set, all the kind of events are processed.
+ * if flags has AE_FILE_EVENTS set, file events are processed.
+ * if flags has AE_TIME_EVENTS set, time events are processed.
+ * if flags has AE_DONT_WAIT set, the function returns ASAP once all
+ * the events that can be handled without a wait are processed.
+ * if flags has AE_CALL_AFTER_SLEEP set, the aftersleep callback is called.
+ * if flags has AE_CALL_BEFORE_SLEEP set, the beforesleep callback is called.
+ *
+ * The function returns the number of events processed. */
+int aeProcessEvents(aeEventLoop *eventLoop, int flags)
+{
+    int processed = 0, numevents;
+
+    /* Nothing to do? return ASAP */
+    if (!(flags & AE_TIME_EVENTS) && !(flags & AE_FILE_EVENTS)) return 0;
+
+    /* Note that we want to call select() even if there are no
+     * file events to process as long as we want to process time
+     * events, in order to sleep until the next time event is ready
+     * to fire. */
+    if (eventLoop->maxfd != -1 ||
+        ((flags & AE_TIME_EVENTS) && !(flags & AE_DONT_WAIT))) {
+        int j;
+        struct timeval tv, *tvp;
+        int64_t usUntilTimer = -1;
+
+        if (flags & AE_TIME_EVENTS && !(flags & AE_DONT_WAIT))
+            usUntilTimer = usUntilEarliestTimer(eventLoop);
+
+        if (usUntilTimer >= 0) {
+            tv.tv_sec = usUntilTimer / 1000000;
+            tv.tv_usec = usUntilTimer % 1000000;
+            tvp = &tv;
+        } else {
+            /* If we have to check for events but need to return
+             * ASAP because of AE_DONT_WAIT we need to set the timeout
+             * to zero */
+            if (flags & AE_DONT_WAIT) {
+                tv.tv_sec = tv.tv_usec = 0;
+                tvp = &tv;
+            } else {
+                /* Otherwise we can block */
+                tvp = NULL; /* wait forever */
+            }
+        }
+
+        if (eventLoop->flags & AE_DONT_WAIT) {
+            tv.tv_sec = tv.tv_usec = 0;
+            tvp = &tv;
+        }
+
+        if (eventLoop->beforesleep != NULL && flags & AE_CALL_BEFORE_SLEEP)
+            eventLoop->beforesleep(eventLoop);
+
+        /* Call the multiplexing API, will return only on timeout or when
+         * some event fires. */
+        numevents = aeApiPoll(eventLoop, tvp);
+
+        /* After sleep callback. */
+        if (eventLoop->aftersleep != NULL && flags & AE_CALL_AFTER_SLEEP)
+            eventLoop->aftersleep(eventLoop);
+
+        for (j = 0; j < numevents; j++) {
+            int fd = eventLoop->fired[j].fd;
+            aeFileEvent *fe = &eventLoop->events[fd];
+            int mask = eventLoop->fired[j].mask;
+            int fired = 0; /* Number of events fired for current fd. */
+
+            /* Normally we execute the readable event first, and the writable
+             * event later. This is useful as sometimes we may be able
+             * to serve the reply of a query immediately after processing the
+             * query.
+             *
+             * However if AE_BARRIER is set in the mask, our application is
+             * asking us to do the reverse: never fire the writable event
+             * after the readable. In such a case, we invert the calls.
+             * This is useful when, for instance, we want to do things
+             * in the beforeSleep() hook, like fsyncing a file to disk,
+             * before replying to a client. */
+            int invert = fe->mask & AE_BARRIER;
+
+            /* Note the "fe->mask & mask & ..." code: maybe an already
+             * processed event removed an element that fired and we still
+             * didn't processed, so we check if the event is still valid.
+             *
+             * Fire the readable event if the call sequence is not
+             * inverted. */
+            if (!invert && fe->mask & mask & AE_READABLE) {
+                fe->rfileProc(eventLoop,fd,fe->clientData,mask);
+                fired++;
+                fe = &eventLoop->events[fd]; /* Refresh in case of resize. */
+            }
+
+            /* Fire the writable event. */
+            if (fe->mask & mask & AE_WRITABLE) {
+                if (!fired || fe->wfileProc != fe->rfileProc) {
+                    fe->wfileProc(eventLoop,fd,fe->clientData,mask);
+                    fired++;
+                }
+            }
+
+            /* If we have to invert the call, fire the readable event now
+             * after the writable one. */
+            if (invert) {
+                fe = &eventLoop->events[fd]; /* Refresh in case of resize. */
+                if ((fe->mask & mask & AE_READABLE) &&
+                    (!fired || fe->wfileProc != fe->rfileProc))
+                {
+                    fe->rfileProc(eventLoop,fd,fe->clientData,mask);
+                    fired++;
+                }
+            }
+
+            processed++;
+        }
+    }
+    /* Check time events */
+    if (flags & AE_TIME_EVENTS)
+        processed += processTimeEvents(eventLoop);
+
+    return processed; /* return the number of processed file/time events */
+}
+
+
+
+void redisAeWriteEvent(aeEventLoop *el, int fd, void *privdata, int mask) {
+    ((void)el); ((void)fd); ((void)mask);
+
+    redisAeEvents *e = (redisAeEvents*)privdata;
+    redisAsyncHandleWrite(e->context);
+}
+
+int aeApiAddEvent(aeEventLoop *eventLoop, int fd, int mask) {
+    aeApiState *state = eventLoop->apidata;
+    struct epoll_event ee = {0}; /* avoid valgrind warning */
+    /* If the fd was already monitored for some event, we need a MOD
+     * operation. Otherwise we need an ADD operation. */
+    int op = eventLoop->events[fd].mask == AE_NONE ?
+             EPOLL_CTL_ADD : EPOLL_CTL_MOD;
+
+    ee.events = 0;
+    mask |= eventLoop->events[fd].mask; /* Merge old events */
+    if (mask & AE_READABLE) ee.events |= EPOLLIN;
+    if (mask & AE_WRITABLE) ee.events |= EPOLLOUT;
+    ee.data.fd = fd;
+    if (epoll_ctl(state->epfd,op,fd,&ee) == -1) return -1;
+    return 0;
+}
+
+int aeCreateFileEvent(aeEventLoop *eventLoop, int fd, int mask,
+                      aeFileProc *proc, void *clientData)
+{
+    if (fd >= eventLoop->setsize) {
+        errno = ERANGE;
+        return AE_ERR;
+    }
+    aeFileEvent *fe = &eventLoop->events[fd];
+
+    if (aeApiAddEvent(eventLoop, fd, mask) == -1)
+        return AE_ERR;
+    fe->mask |= mask;
+    if (mask & AE_READABLE) fe->rfileProc = proc;
+    if (mask & AE_WRITABLE) fe->wfileProc = proc;
+    fe->clientData = clientData;
+    if (fd > eventLoop->maxfd)
+        eventLoop->maxfd = fd;
+    return AE_OK;
+}
+
+void redisAeAddRead(void *privdata) {
+    redisAeEvents *e = (redisAeEvents*)privdata;
+    aeEventLoop *loop = e->loop;
+    if (!e->reading) {
+        e->reading = 1;
+        aeCreateFileEvent(loop,e->fd,AE_READABLE,redisAeReadEvent,e);
+    }
+}
+
+void aeApiDelEvent(aeEventLoop *eventLoop, int fd, int delmask) {
+    aeApiState *state = eventLoop->apidata;
+    struct epoll_event ee = {0}; /* avoid valgrind warning */
+    int mask = eventLoop->events[fd].mask & (~delmask);
+
+    ee.events = 0;
+    if (mask & AE_READABLE) ee.events |= EPOLLIN;
+    if (mask & AE_WRITABLE) ee.events |= EPOLLOUT;
+    ee.data.fd = fd;
+    if (mask != AE_NONE) {
+        epoll_ctl(state->epfd,EPOLL_CTL_MOD,fd,&ee);
+    } else {
+        /* Note, Kernel < 2.6.9 requires a non null event pointer even for
+         * EPOLL_CTL_DEL. */
+        epoll_ctl(state->epfd,EPOLL_CTL_DEL,fd,&ee);
+    }
+}
+
+void aeDeleteFileEvent(aeEventLoop *eventLoop, int fd, int mask)
+{
+    if (fd >= eventLoop->setsize) return;
+    aeFileEvent *fe = &eventLoop->events[fd];
+    if (fe->mask == AE_NONE) return;
+
+    /* We want to always remove AE_BARRIER if set when AE_WRITABLE
+     * is removed. */
+    if (mask & AE_WRITABLE) mask |= AE_BARRIER;
+
+    aeApiDelEvent(eventLoop, fd, mask);
+    fe->mask = fe->mask & (~mask);
+    if (fd == eventLoop->maxfd && fe->mask == AE_NONE) {
+        /* Update the max fd */
+        int j;
+
+        for (j = eventLoop->maxfd-1; j >= 0; j--)
+            if (eventLoop->events[j].mask != AE_NONE) break;
+        eventLoop->maxfd = j;
+    }
+}
+
+void redisAeDelRead(void *privdata) {
+    redisAeEvents *e = (redisAeEvents*)privdata;
+    aeEventLoop *loop = e->loop;
+    if (e->reading) {
+        e->reading = 0;
+        aeDeleteFileEvent(loop,e->fd,AE_READABLE);
+    }
+}
+
+void redisAeAddWrite(void *privdata) {
+    redisAeEvents *e = (redisAeEvents*)privdata;
+    aeEventLoop *loop = e->loop;
+    if (!e->writing) {
+        e->writing = 1;
+        aeCreateFileEvent(loop,e->fd,AE_WRITABLE,redisAeWriteEvent,e);
+    }
+}
+
+void redisAeDelWrite(void *privdata) {
+    redisAeEvents *e = (redisAeEvents*)privdata;
+    aeEventLoop *loop = e->loop;
+    if (e->writing) {
+        e->writing = 0;
+        aeDeleteFileEvent(loop,e->fd,AE_WRITABLE);
+    }
+}
+
+void redisAeCleanup(void *privdata) {
+    redisAeEvents *e = (redisAeEvents*)privdata;
+    redisAeDelRead(privdata);
+    redisAeDelWrite(privdata);
+    hi_free(e);
+}
+
+/* Enable the FD_CLOEXEC on the given fd to avoid fd leaks.
+ * This function should be invoked for fd's on specific places
+ * where fork + execve system calls are called. */
+int anetCloexec(int fd) {
+    int r;
+    int flags;
+
+    do {
+        r = fcntl(fd, F_GETFD);
+    } while (r == -1 && errno == EINTR);
+
+    if (r == -1 || (r & FD_CLOEXEC))
+        return r;
+
+    flags = r | FD_CLOEXEC;
+
+    do {
+        r = fcntl(fd, F_SETFD, flags);
+    } while (r == -1 && errno == EINTR);
+
+    return r;
+}
+
+int aeApiCreate(aeEventLoop *eventLoop) {
+    aeApiState *state = hi_malloc(sizeof(aeApiState));
+
+    if (!state) return -1;
+    state->events = hi_malloc(sizeof(struct epoll_event)*eventLoop->setsize);
+    if (!state->events) {
+        hi_free(state);
+        return -1;
+    }
+    state->epfd = epoll_create(1024); /* 1024 is just a hint for the kernel */
+    if (state->epfd == -1) {
+        hi_free(state->events);
+        hi_free(state);
+        return -1;
+    }
+    anetCloexec(state->epfd);
+    eventLoop->apidata = state;
+    return 0;
+}
+
+aeEventLoop *aeCreateEventLoop(int setsize) {
+    aeEventLoop *eventLoop;
+    int i;
+
+    if ((eventLoop = hi_malloc(sizeof(*eventLoop))) == NULL) goto err;
+    eventLoop->events = hi_malloc(sizeof(aeFileEvent)*setsize);
+    eventLoop->fired = hi_malloc(sizeof(aeFiredEvent)*setsize);
+    if (eventLoop->events == NULL || eventLoop->fired == NULL) goto err;
+    eventLoop->setsize = setsize;
+    eventLoop->timeEventHead = NULL;
+    eventLoop->timeEventNextId = 0;
+    eventLoop->stop = 0;
+    eventLoop->maxfd = -1;
+    eventLoop->beforesleep = NULL;
+    eventLoop->aftersleep = NULL;
+    eventLoop->flags = 0;
+    if (aeApiCreate(eventLoop) == -1) goto err;
+    /* Events with mask == AE_NONE are not set. So let's initialize the
+     * vector with it. */
+    for (i = 0; i < setsize; i++)
+        eventLoop->events[i].mask = AE_NONE;
+    return eventLoop;
+
+    err:
+    if (eventLoop) {
+        hi_free(eventLoop->events);
+        hi_free(eventLoop->fired);
+        hi_free(eventLoop);
+    }
+    return NULL;
+}
+
+int redisAeAttach(aeEventLoop *loop, redisAsyncContext *ac) {
+    redisContext *c = &(ac->c);
+    redisAeEvents *e;
+
+    /* Nothing should be attached when something is already attached */
+    if (ac->ev.data != NULL)
+        return REDIS_ERR;
+
+    /* Create container for context and r/w events */
+    e = (redisAeEvents *) hi_malloc(sizeof(*e));
+    if (e == NULL)
+        return REDIS_ERR;
+
+    e->context = ac;
+    e->loop = loop;
+    e->fd = c->fd;
+    e->reading = e->writing = 0;
+
+    /* Register functions to start/stop listening for events */
+    ac->ev.addRead = redisAeAddRead;
+    ac->ev.delRead = redisAeDelRead;
+    ac->ev.addWrite = redisAeAddWrite;
+    ac->ev.delWrite = redisAeDelWrite;
+    ac->ev.cleanup = redisAeCleanup;
+    ac->ev.data = e;
+
+    return REDIS_OK;
+}
+
+

src/ae.h

@@ -0,0 +1,133 @@
+#ifndef __HIREDIS_AE_H__
+#define __HIREDIS_AE_H__
+
+
+#include "hiredis.h"
+#include "async.h"
+
+
+typedef uint64_t monotime;
+
+#define AE_OK 0
+#define AE_ERR -1
+#define AE_NONE 0       /* No events registered. */
+#define AE_READABLE 1   /* Fire when descriptor is readable. */
+#define AE_WRITABLE 2   /* Fire when descriptor is writable. */
+#define AE_BARRIER 4    /* With WRITABLE, never fire the event if the
+                           READABLE event already fired in the same event
+                           loop iteration. Useful when you want to persist
+                           things to disk before sending replies, and want
+                           to do that in a group fashion. */
+
+/* Types and data structures */
+typedef void aeFileProc(struct aeEventLoop *eventLoop, int fd, void *clientData, int mask);
+
+typedef int aeTimeProc(struct aeEventLoop *eventLoop, long long id, void *clientData);
+
+typedef void aeEventFinalizerProc(struct aeEventLoop *eventLoop, void *clientData);
+
+typedef void aeBeforeSleepProc(struct aeEventLoop *eventLoop);
+
+/* File event structure */
+typedef struct aeFileEvent {
+    int mask; /* one of AE_(READABLE|WRITABLE|BARRIER) */
+    aeFileProc *rfileProc;
+    aeFileProc *wfileProc;
+    void *clientData;
+} aeFileEvent;
+
+/* Time event structure */
+typedef struct aeTimeEvent {
+    long long id; /* time event identifier. */
+    monotime when;
+    aeTimeProc *timeProc;
+    aeEventFinalizerProc *finalizerProc;
+    void *clientData;
+    struct aeTimeEvent *prev;
+    struct aeTimeEvent *next;
+    int refcount; /* refcount to prevent timer events from being
+  		   * freed in recursive time event calls. */
+} aeTimeEvent;
+
+/* A fired event */
+typedef struct aeFiredEvent {
+    int fd;
+    int mask;
+} aeFiredEvent;
+
+typedef struct aeEventLoop {
+    int maxfd;   /* highest file descriptor currently registered */
+    int setsize; /* max number of file descriptors tracked */
+    long long timeEventNextId;
+    aeFileEvent *events; /* Registered events */
+    aeFiredEvent *fired; /* Fired events */
+    aeTimeEvent *timeEventHead;
+    int stop;
+    void *apidata; /* This is used for polling API specific data */
+    aeBeforeSleepProc *beforesleep;
+    aeBeforeSleepProc *aftersleep;
+    int flags;
+} aeEventLoop;
+
+typedef struct redisAeEvents {
+    redisAsyncContext *context;
+    aeEventLoop *loop;
+    int fd;
+    int reading, writing;
+} redisAeEvents;
+
+typedef struct aeApiState {
+    int epfd;
+    struct epoll_event *events;
+} aeApiState;
+
+#define AE_FILE_EVENTS (1<<0)
+#define AE_TIME_EVENTS (1<<1)
+#define AE_ALL_EVENTS (AE_FILE_EVENTS|AE_TIME_EVENTS)
+#define AE_DONT_WAIT (1<<2)
+#define AE_CALL_BEFORE_SLEEP (1<<3)
+#define AE_CALL_AFTER_SLEEP (1<<4)
+
+#define AE_NOMORE -1
+#define AE_DELETED_EVENT_ID -1
+
+extern monotime (*getMonotonicUs)(void);
+
+void redisAeReadEvent(aeEventLoop *el, int fd, void *privdata, int mask);
+
+void redisAeWriteEvent(aeEventLoop *el, int fd, void *privdata, int mask);
+
+int aeApiAddEvent(aeEventLoop *eventLoop, int fd, int mask);
+
+void aeStop(aeEventLoop *eventLoop);
+
+void aeMain(aeEventLoop *eventLoop);
+
+int aeProcessEvents(aeEventLoop *eventLoop, int flags);
+
+int aeCreateFileEvent(aeEventLoop *eventLoop, int fd, int mask,
+                      aeFileProc *proc, void *clientData);
+
+void redisAeAddRead(void *privdata);
+
+void aeApiDelEvent(aeEventLoop *eventLoop, int fd, int delmask);
+
+void aeDeleteFileEvent(aeEventLoop *eventLoop, int fd, int mask);
+
+void redisAeDelRead(void *privdata);
+
+void redisAeAddWrite(void *privdata);
+
+void redisAeDelWrite(void *privdata);
+
+void redisAeCleanup(void *privdata);
+
+int anetCloexec(int fd);
+
+static int aeApiCreate(aeEventLoop *eventLoop);
+
+aeEventLoop *aeCreateEventLoop(int setsize);
+
+int redisAeAttach(aeEventLoop *loop, redisAsyncContext *ac);
+
+#endif

src/alloc.c

@@ -0,0 +1,90 @@
+/*
+ * Copyright (c) 2020, Michael Grunder <michael dot grunder at gmail dot com>
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "fmacros.h"
+#include "alloc.h"
+#include <string.h>
+#include <stdlib.h>
+
+hiredisAllocFuncs hiredisAllocFns = {
+    .mallocFn = malloc,
+    .callocFn = calloc,
+    .reallocFn = realloc,
+    .strdupFn = strdup,
+    .freeFn = free,
+};
+
+/* Override hiredis' allocators with ones supplied by the user */
+hiredisAllocFuncs hiredisSetAllocators(hiredisAllocFuncs *override) {
+    hiredisAllocFuncs orig = hiredisAllocFns;
+
+    hiredisAllocFns = *override;
+
+    return orig;
+}
+
+/* Reset allocators to use libc defaults */
+void hiredisResetAllocators(void) {
+    hiredisAllocFns = (hiredisAllocFuncs) {
+        .mallocFn = malloc,
+        .callocFn = calloc,
+        .reallocFn = realloc,
+        .strdupFn = strdup,
+        .freeFn = free,
+    };
+}
+
+#ifdef _WIN32
+
+void *hi_malloc(size_t size) {
+    return hiredisAllocFns.mallocFn(size);
+}
+
+void *hi_calloc(size_t nmemb, size_t size) {
+    /* Overflow check as the user can specify any arbitrary allocator */
+    if (SIZE_MAX / size < nmemb)
+        return NULL;
+
+    return hiredisAllocFns.callocFn(nmemb, size);
+}
+
+void *hi_realloc(void *ptr, size_t size) {
+    return hiredisAllocFns.reallocFn(ptr, size);
+}
+
+char *hi_strdup(const char *str) {
+    return hiredisAllocFns.strdupFn(str);
+}
+
+void hi_free(void *ptr) {
+    hiredisAllocFns.freeFn(ptr);
+}
+
+#endif

src/alloc.h

@@ -0,0 +1,96 @@
+/*
+ * Copyright (c) 2020, Michael Grunder <michael dot grunder at gmail dot com>
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef HIREDIS_ALLOC_H
+#define HIREDIS_ALLOC_H
+
+#include <stddef.h> /* for size_t */
+#include <stdint.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* Structure pointing to our actually configured allocators */
+typedef struct hiredisAllocFuncs {
+    void *(*mallocFn)(size_t);
+    void *(*callocFn)(size_t,size_t);
+    void *(*reallocFn)(void*,size_t);
+    char *(*strdupFn)(const char*);
+    void (*freeFn)(void*);
+} hiredisAllocFuncs;
+
+hiredisAllocFuncs hiredisSetAllocators(hiredisAllocFuncs *ha);
+void hiredisResetAllocators(void);
+
+#ifndef _WIN32
+
+/* Hiredis' configured allocator function pointer struct */
+extern hiredisAllocFuncs hiredisAllocFns;
+
+static inline void *hi_malloc(size_t size) {
+    return hiredisAllocFns.mallocFn(size);
+}
+
+static inline void *hi_calloc(size_t nmemb, size_t size) {
+    /* Overflow check as the user can specify any arbitrary allocator */
+    if (SIZE_MAX / size < nmemb)
+        return NULL;
+
+    return hiredisAllocFns.callocFn(nmemb, size);
+}
+
+static inline void *hi_realloc(void *ptr, size_t size) {
+    return hiredisAllocFns.reallocFn(ptr, size);
+}
+
+static inline char *hi_strdup(const char *str) {
+    return hiredisAllocFns.strdupFn(str);
+}
+
+static inline void hi_free(void *ptr) {
+    hiredisAllocFns.freeFn(ptr);
+}
+
+#else
+
+void *hi_malloc(size_t size);
+void *hi_calloc(size_t nmemb, size_t size);
+void *hi_realloc(void *ptr, size_t size);
+char *hi_strdup(const char *str);
+void hi_free(void *ptr);
+
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* HIREDIS_ALLOC_H */

src/async.c

@@ -0,0 +1,908 @@
+/*
+ * Copyright (c) 2009-2011, Salvatore Sanfilippo <antirez at gmail dot com>
+ * Copyright (c) 2010-2011, Pieter Noordhuis <pcnoordhuis at gmail dot com>
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "fmacros.h"
+#include "alloc.h"
+#include <stdlib.h>
+#include <string.h>
+#ifndef _MSC_VER
+#include <strings.h>
+#endif
+#include <assert.h>
+#include <ctype.h>
+#include <errno.h>
+#include "async.h"
+#include "net.h"
+#include "dict.c"
+#include "sds.h"
+
+#include "async_private.h"
+
+#ifdef NDEBUG
+#undef assert
+#define assert(e) (void)(e)
+#endif
+
+/* Forward declarations of hiredis.c functions */
+int __redisAppendCommand(redisContext *c, const char *cmd, size_t len);
+void __redisSetError(redisContext *c, int type, const char *str);
+
+/* Functions managing dictionary of callbacks for pub/sub. */
+static unsigned int callbackHash(const void *key) {
+    return dictGenHashFunction((const unsigned char *)key,
+                               hi_sdslen((const hisds)key));
+}
+
+static void *callbackValDup(void *privdata, const void *src) {
+    ((void) privdata);
+    redisCallback *dup;
+
+    dup = hi_malloc(sizeof(*dup));
+    if (dup == NULL)
+        return NULL;
+
+    memcpy(dup,src,sizeof(*dup));
+    return dup;
+}
+
+static int callbackKeyCompare(void *privdata, const void *key1, const void *key2) {
+    int l1, l2;
+    ((void) privdata);
+
+    l1 = hi_sdslen((const hisds)key1);
+    l2 = hi_sdslen((const hisds)key2);
+    if (l1 != l2) return 0;
+    return memcmp(key1,key2,l1) == 0;
+}
+
+static void callbackKeyDestructor(void *privdata, void *key) {
+    ((void) privdata);
+    hi_sdsfree((hisds)key);
+}
+
+static void callbackValDestructor(void *privdata, void *val) {
+    ((void) privdata);
+    hi_free(val);
+}
+
+static dictType callbackDict = {
+    callbackHash,
+    NULL,
+    callbackValDup,
+    callbackKeyCompare,
+    callbackKeyDestructor,
+    callbackValDestructor
+};
+
+static redisAsyncContext *redisAsyncInitialize(redisContext *c) {
+    redisAsyncContext *ac;
+    dict *channels = NULL, *patterns = NULL;
+
+    channels = dictCreate(&callbackDict,NULL);
+    if (channels == NULL)
+        goto oom;
+
+    patterns = dictCreate(&callbackDict,NULL);
+    if (patterns == NULL)
+        goto oom;
+
+    ac = hi_realloc(c,sizeof(redisAsyncContext));
+    if (ac == NULL)
+        goto oom;
+
+    c = &(ac->c);
+
+    /* The regular connect functions will always set the flag REDIS_CONNECTED.
+     * For the async API, we want to wait until the first write event is
+     * received up before setting this flag, so reset it here. */
+    c->flags &= ~REDIS_CONNECTED;
+
+    ac->err = 0;
+    ac->errstr = NULL;
+    ac->data = NULL;
+    ac->dataCleanup = NULL;
+
+    ac->ev.data = NULL;
+    ac->ev.addRead = NULL;
+    ac->ev.delRead = NULL;
+    ac->ev.addWrite = NULL;
+    ac->ev.delWrite = NULL;
+    ac->ev.cleanup = NULL;
+    ac->ev.scheduleTimer = NULL;
+
+    ac->onConnect = NULL;
+    ac->onDisconnect = NULL;
+
+    ac->replies.head = NULL;
+    ac->replies.tail = NULL;
+    ac->sub.replies.head = NULL;
+    ac->sub.replies.tail = NULL;
+    ac->sub.channels = channels;
+    ac->sub.patterns = patterns;
+
+    return ac;
+oom:
+    if (channels) dictRelease(channels);
+    if (patterns) dictRelease(patterns);
+    return NULL;
+}
+
+/* We want the error field to be accessible directly instead of requiring
+ * an indirection to the redisContext struct. */
+static void __redisAsyncCopyError(redisAsyncContext *ac) {
+    if (!ac)
+        return;
+
+    redisContext *c = &(ac->c);
+    ac->err = c->err;
+    ac->errstr = c->errstr;
+}
+
+redisAsyncContext *redisAsyncConnectWithOptions(const redisOptions *options) {
+    redisOptions myOptions = *options;
+    redisContext *c;
+    redisAsyncContext *ac;
+
+    /* Clear any erroneously set sync callback and flag that we don't want to
+     * use freeReplyObject by default. */
+    myOptions.push_cb = NULL;
+    myOptions.options |= REDIS_OPT_NO_PUSH_AUTOFREE;
+
+    myOptions.options |= REDIS_OPT_NONBLOCK;
+    c = redisConnectWithOptions(&myOptions);
+    if (c == NULL) {
+        return NULL;
+    }
+
+    ac = redisAsyncInitialize(c);
+    if (ac == NULL) {
+        redisFree(c);
+        return NULL;
+    }
+
+    /* Set any configured async push handler */
+    redisAsyncSetPushCallback(ac, myOptions.async_push_cb);
+
+    __redisAsyncCopyError(ac);
+    return ac;
+}
+
+redisAsyncContext *redisAsyncConnect(const char *ip, int port) {
+    redisOptions options = {0};
+    REDIS_OPTIONS_SET_TCP(&options, ip, port);
+    return redisAsyncConnectWithOptions(&options);
+}
+
+redisAsyncContext *redisAsyncConnectBind(const char *ip, int port,
+                                         const char *source_addr) {
+    redisOptions options = {0};
+    REDIS_OPTIONS_SET_TCP(&options, ip, port);
+    options.endpoint.tcp.source_addr = source_addr;
+    return redisAsyncConnectWithOptions(&options);
+}
+
+redisAsyncContext *redisAsyncConnectBindWithReuse(const char *ip, int port,
+                                                  const char *source_addr) {
+    redisOptions options = {0};
+    REDIS_OPTIONS_SET_TCP(&options, ip, port);
+    options.options |= REDIS_OPT_REUSEADDR;
+    options.endpoint.tcp.source_addr = source_addr;
+    return redisAsyncConnectWithOptions(&options);
+}
+
+redisAsyncContext *redisAsyncConnectUnix(const char *path) {
+    redisOptions options = {0};
+    REDIS_OPTIONS_SET_UNIX(&options, path);
+    return redisAsyncConnectWithOptions(&options);
+}
+
+int redisAsyncSetConnectCallback(redisAsyncContext *ac, redisConnectCallback *fn) {
+    if (ac->onConnect == NULL) {
+        ac->onConnect = fn;
+
+        /* The common way to detect an established connection is to wait for
+         * the first write event to be fired. This assumes the related event
+         * library functions are already set. */
+        _EL_ADD_WRITE(ac);
+        return REDIS_OK;
+    }
+    return REDIS_ERR;
+}
+
+int redisAsyncSetDisconnectCallback(redisAsyncContext *ac, redisDisconnectCallback *fn) {
+    if (ac->onDisconnect == NULL) {
+        ac->onDisconnect = fn;
+        return REDIS_OK;
+    }
+    return REDIS_ERR;
+}
+
+/* Helper functions to push/shift callbacks */
+static int __redisPushCallback(redisCallbackList *list, redisCallback *source) {
+    redisCallback *cb;
+
+    /* Copy callback from stack to heap */
+    cb = hi_malloc(sizeof(*cb));
+    if (cb == NULL)
+        return REDIS_ERR_OOM;
+
+    if (source != NULL) {
+        memcpy(cb,source,sizeof(*cb));
+        cb->next = NULL;
+    }
+
+    /* Store callback in list */
+    if (list->head == NULL)
+        list->head = cb;
+    if (list->tail != NULL)
+        list->tail->next = cb;
+    list->tail = cb;
+    return REDIS_OK;
+}
+
+static int __redisShiftCallback(redisCallbackList *list, redisCallback *target) {
+    redisCallback *cb = list->head;
+    if (cb != NULL) {
+        list->head = cb->next;
+        if (cb == list->tail)
+            list->tail = NULL;
+
+        /* Copy callback from heap to stack */
+        if (target != NULL)
+            memcpy(target,cb,sizeof(*cb));
+        hi_free(cb);
+        return REDIS_OK;
+    }
+    return REDIS_ERR;
+}
+
+static void __redisRunCallback(redisAsyncContext *ac, redisCallback *cb, redisReply *reply) {
+    redisContext *c = &(ac->c);
+    if (cb->fn != NULL) {
+        c->flags |= REDIS_IN_CALLBACK;
+        cb->fn(ac,reply,cb->privdata);
+        c->flags &= ~REDIS_IN_CALLBACK;
+    }
+}
+
+static void __redisRunPushCallback(redisAsyncContext *ac, redisReply *reply) {
+    if (ac->push_cb != NULL) {
+        ac->c.flags |= REDIS_IN_CALLBACK;
+        ac->push_cb(ac, reply);
+        ac->c.flags &= ~REDIS_IN_CALLBACK;
+    }
+}
+
+/* Helper function to free the context. */
+static void __redisAsyncFree(redisAsyncContext *ac) {
+    redisContext *c = &(ac->c);
+    redisCallback cb;
+    dictIterator it;
+    dictEntry *de;
+
+    /* Execute pending callbacks with NULL reply. */
+    while (__redisShiftCallback(&ac->replies,&cb) == REDIS_OK)
+        __redisRunCallback(ac,&cb,NULL);
+    while (__redisShiftCallback(&ac->sub.replies,&cb) == REDIS_OK)
+        __redisRunCallback(ac,&cb,NULL);
+
+    /* Run subscription callbacks with NULL reply */
+    if (ac->sub.channels) {
+        dictInitIterator(&it,ac->sub.channels);
+        while ((de = dictNext(&it)) != NULL)
+            __redisRunCallback(ac,dictGetEntryVal(de),NULL);
+
+        dictRelease(ac->sub.channels);
+    }
+
+    if (ac->sub.patterns) {
+        dictInitIterator(&it,ac->sub.patterns);
+        while ((de = dictNext(&it)) != NULL)
+            __redisRunCallback(ac,dictGetEntryVal(de),NULL);
+
+        dictRelease(ac->sub.patterns);
+    }
+
+    /* Signal event lib to clean up */
+    _EL_CLEANUP(ac);
+
+    /* Execute disconnect callback. When redisAsyncFree() initiated destroying
+     * this context, the status will always be REDIS_OK. */
+    if (ac->onDisconnect && (c->flags & REDIS_CONNECTED)) {
+        if (c->flags & REDIS_FREEING) {
+            ac->onDisconnect(ac,REDIS_OK);
+        } else {
+            ac->onDisconnect(ac,(ac->err == 0) ? REDIS_OK : REDIS_ERR);
+        }
+    }
+
+    if (ac->dataCleanup) {
+        ac->dataCleanup(ac->data);
+    }
+
+    /* Cleanup self */
+    redisFree(c);
+}
+
+/* Free the async context. When this function is called from a callback,
+ * control needs to be returned to redisProcessCallbacks() before actual
+ * free'ing. To do so, a flag is set on the context which is picked up by
+ * redisProcessCallbacks(). Otherwise, the context is immediately free'd. */
+void redisAsyncFree(redisAsyncContext *ac) {
+    redisContext *c = &(ac->c);
+    c->flags |= REDIS_FREEING;
+    if (!(c->flags & REDIS_IN_CALLBACK))
+        __redisAsyncFree(ac);
+}
+
+/* Helper function to make the disconnect happen and clean up. */
+void __redisAsyncDisconnect(redisAsyncContext *ac) {
+    redisContext *c = &(ac->c);
+
+    /* Make sure error is accessible if there is any */
+    __redisAsyncCopyError(ac);
+
+    if (ac->err == 0) {
+        /* For clean disconnects, there should be no pending callbacks. */
+        int ret = __redisShiftCallback(&ac->replies,NULL);
+        assert(ret == REDIS_ERR);
+    } else {
+        /* Disconnection is caused by an error, make sure that pending
+         * callbacks cannot call new commands. */
+        c->flags |= REDIS_DISCONNECTING;
+    }
+
+    /* cleanup event library on disconnect.
+     * this is safe to call multiple times */
+    _EL_CLEANUP(ac);
+
+    /* For non-clean disconnects, __redisAsyncFree() will execute pending
+     * callbacks with a NULL-reply. */
+    if (!(c->flags & REDIS_NO_AUTO_FREE)) {
+      __redisAsyncFree(ac);
+    }
+}
+
+/* Tries to do a clean disconnect from Redis, meaning it stops new commands
+ * from being issued, but tries to flush the output buffer and execute
+ * callbacks for all remaining replies. When this function is called from a
+ * callback, there might be more replies and we can safely defer disconnecting
+ * to redisProcessCallbacks(). Otherwise, we can only disconnect immediately
+ * when there are no pending callbacks. */
+void redisAsyncDisconnect(redisAsyncContext *ac) {
+    redisContext *c = &(ac->c);
+    c->flags |= REDIS_DISCONNECTING;
+
+    /** unset the auto-free flag here, because disconnect undoes this */
+    c->flags &= ~REDIS_NO_AUTO_FREE;
+    if (!(c->flags & REDIS_IN_CALLBACK) && ac->replies.head == NULL)
+        __redisAsyncDisconnect(ac);
+}
+
+static int __redisGetSubscribeCallback(redisAsyncContext *ac, redisReply *reply, redisCallback *dstcb) {
+    redisContext *c = &(ac->c);
+    dict *callbacks;
+    redisCallback *cb;
+    dictEntry *de;
+    int pvariant;
+    char *stype;
+    hisds sname;
+
+    /* Match reply with the expected format of a pushed message.
+     * The type and number of elements (3 to 4) are specified at:
+     * https://redis.io/topics/pubsub#format-of-pushed-messages */
+    if ((reply->type == REDIS_REPLY_ARRAY && !(c->flags & REDIS_SUPPORTS_PUSH) && reply->elements >= 3) ||
+        reply->type == REDIS_REPLY_PUSH) {
+        assert(reply->element[0]->type == REDIS_REPLY_STRING);
+        stype = reply->element[0]->str;
+        pvariant = (tolower(stype[0]) == 'p') ? 1 : 0;
+
+        if (pvariant)
+            callbacks = ac->sub.patterns;
+        else
+            callbacks = ac->sub.channels;
+
+        /* Locate the right callback */
+        assert(reply->element[1]->type == REDIS_REPLY_STRING);
+        sname = hi_sdsnewlen(reply->element[1]->str,reply->element[1]->len);
+        if (sname == NULL)
+            goto oom;
+
+        de = dictFind(callbacks,sname);
+        if (de != NULL) {
+            cb = dictGetEntryVal(de);
+
+            /* If this is an subscribe reply decrease pending counter. */
+            if (strcasecmp(stype+pvariant,"subscribe") == 0) {
+                cb->pending_subs -= 1;
+            }
+
+            memcpy(dstcb,cb,sizeof(*dstcb));
+
+            /* If this is an unsubscribe message, remove it. */
+            if (strcasecmp(stype+pvariant,"unsubscribe") == 0) {
+                if (cb->pending_subs == 0)
+                    dictDelete(callbacks,sname);
+
+                /* If this was the last unsubscribe message, revert to
+                 * non-subscribe mode. */
+                assert(reply->element[2]->type == REDIS_REPLY_INTEGER);
+
+                /* Unset subscribed flag only when no pipelined pending subscribe. */
+                if (reply->element[2]->integer == 0
+                    && dictSize(ac->sub.channels) == 0
+                    && dictSize(ac->sub.patterns) == 0) {
+                    c->flags &= ~REDIS_SUBSCRIBED;
+
+                    /* Move ongoing regular command callbacks. */
+                    redisCallback cb;
+                    while (__redisShiftCallback(&ac->sub.replies,&cb) == REDIS_OK) {
+                        __redisPushCallback(&ac->replies,&cb);
+                    }
+                }
+            }
+        }
+        hi_sdsfree(sname);
+    } else {
+        /* Shift callback for pending command in subscribed context. */
+        __redisShiftCallback(&ac->sub.replies,dstcb);
+    }
+    return REDIS_OK;
+oom:
+    __redisSetError(&(ac->c), REDIS_ERR_OOM, "Out of memory");
+    return REDIS_ERR;
+}
+
+#define redisIsSpontaneousPushReply(r) \
+    (redisIsPushReply(r) && !redisIsSubscribeReply(r))
+
+static int redisIsSubscribeReply(redisReply *reply) {
+    char *str;
+    size_t len, off;
+
+    /* We will always have at least one string with the subscribe/message type */
+    if (reply->elements < 1 || reply->element[0]->type != REDIS_REPLY_STRING ||
+        reply->element[0]->len < sizeof("message") - 1)
+    {
+        return 0;
+    }
+
+    /* Get the string/len moving past 'p' if needed */
+    off = tolower(reply->element[0]->str[0]) == 'p';
+    str = reply->element[0]->str + off;
+    len = reply->element[0]->len - off;
+
+    return !strncasecmp(str, "subscribe", len) ||
+           !strncasecmp(str, "message", len) ||
+           !strncasecmp(str, "unsubscribe", len);
+}
+
+void redisProcessCallbacks(redisAsyncContext *ac) {
+    redisContext *c = &(ac->c);
+    void *reply = NULL;
+    int status;
+
+    while((status = redisGetReply(c,&reply)) == REDIS_OK) {
+        if (reply == NULL) {
+            /* When the connection is being disconnected and there are
+             * no more replies, this is the cue to really disconnect. */
+            if (c->flags & REDIS_DISCONNECTING && hi_sdslen(c->obuf) == 0
+                && ac->replies.head == NULL) {
+                __redisAsyncDisconnect(ac);
+                return;
+            }
+            /* When the connection is not being disconnected, simply stop
+             * trying to get replies and wait for the next loop tick. */
+            break;
+        }
+
+        /* Keep track of push message support for subscribe handling */
+        if (redisIsPushReply(reply)) c->flags |= REDIS_SUPPORTS_PUSH;
+
+        /* Send any non-subscribe related PUSH messages to our PUSH handler
+         * while allowing subscribe related PUSH messages to pass through.
+         * This allows existing code to be backward compatible and work in
+         * either RESP2 or RESP3 mode. */
+        if (redisIsSpontaneousPushReply(reply)) {
+            __redisRunPushCallback(ac, reply);
+            c->reader->fn->freeObject(reply);
+            continue;
+        }
+
+        /* Even if the context is subscribed, pending regular
+         * callbacks will get a reply before pub/sub messages arrive. */
+        redisCallback cb = {NULL, NULL, 0, NULL};
+        if (__redisShiftCallback(&ac->replies,&cb) != REDIS_OK) {
+            /*
+             * A spontaneous reply in a not-subscribed context can be the error
+             * reply that is sent when a new connection exceeds the maximum
+             * number of allowed connections on the server side.
+             *
+             * This is seen as an error instead of a regular reply because the
+             * server closes the connection after sending it.
+             *
+             * To prevent the error from being overwritten by an EOF error the
+             * connection is closed here. See issue #43.
+             *
+             * Another possibility is that the server is loading its dataset.
+             * In this case we also want to close the connection, and have the
+             * user wait until the server is ready to take our request.
+             */
+            if (((redisReply*)reply)->type == REDIS_REPLY_ERROR) {
+                c->err = REDIS_ERR_OTHER;
+                snprintf(c->errstr,sizeof(c->errstr),"%s",((redisReply*)reply)->str);
+                c->reader->fn->freeObject(reply);
+                __redisAsyncDisconnect(ac);
+                return;
+            }
+            /* No more regular callbacks and no errors, the context *must* be subscribed. */
+            assert(c->flags & REDIS_SUBSCRIBED);
+            if (c->flags & REDIS_SUBSCRIBED)
+                __redisGetSubscribeCallback(ac,reply,&cb);
+        }
+
+        if (cb.fn != NULL) {
+            __redisRunCallback(ac,&cb,reply);
+            if (!(c->flags & REDIS_NO_AUTO_FREE_REPLIES)){
+                c->reader->fn->freeObject(reply);
+            }
+
+            /* Proceed with free'ing when redisAsyncFree() was called. */
+            if (c->flags & REDIS_FREEING) {
+                __redisAsyncFree(ac);
+                return;
+            }
+        } else {
+            /* No callback for this reply. This can either be a NULL callback,
+             * or there were no callbacks to begin with. Either way, don't
+             * abort with an error, but simply ignore it because the client
+             * doesn't know what the server will spit out over the wire. */
+            c->reader->fn->freeObject(reply);
+        }
+
+        /* If in monitor mode, repush the callback */
+        if (c->flags & REDIS_MONITORING) {
+            __redisPushCallback(&ac->replies,&cb);
+        }
+    }
+
+    /* Disconnect when there was an error reading the reply */
+    if (status != REDIS_OK)
+        __redisAsyncDisconnect(ac);
+}
+
+static void __redisAsyncHandleConnectFailure(redisAsyncContext *ac) {
+    if (ac->onConnect) ac->onConnect(ac, REDIS_ERR);
+    __redisAsyncDisconnect(ac);
+}
+
+/* Internal helper function to detect socket status the first time a read or
+ * write event fires. When connecting was not successful, the connect callback
+ * is called with a REDIS_ERR status and the context is free'd. */
+static int __redisAsyncHandleConnect(redisAsyncContext *ac) {
+    int completed = 0;
+    redisContext *c = &(ac->c);
+
+    if (redisCheckConnectDone(c, &completed) == REDIS_ERR) {
+        /* Error! */
+        if (redisCheckSocketError(c) == REDIS_ERR)
+            __redisAsyncCopyError(ac);
+        __redisAsyncHandleConnectFailure(ac);
+        return REDIS_ERR;
+    } else if (completed == 1) {
+        /* connected! */
+        if (c->connection_type == REDIS_CONN_TCP &&
+            redisSetTcpNoDelay(c) == REDIS_ERR) {
+            __redisAsyncHandleConnectFailure(ac);
+            return REDIS_ERR;
+        }
+
+        if (ac->onConnect) ac->onConnect(ac, REDIS_OK);
+        c->flags |= REDIS_CONNECTED;
+        return REDIS_OK;
+    } else {
+        return REDIS_OK;
+    }
+}
+
+void redisAsyncRead(redisAsyncContext *ac) {
+    redisContext *c = &(ac->c);
+
+    if (redisBufferRead(c) == REDIS_ERR) {
+        __redisAsyncDisconnect(ac);
+    } else {
+        /* Always re-schedule reads */
+        _EL_ADD_READ(ac);
+        redisProcessCallbacks(ac);
+    }
+}
+
+/* This function should be called when the socket is readable.
+ * It processes all replies that can be read and executes their callbacks.
+ */
+void redisAsyncHandleRead(redisAsyncContext *ac) {
+    redisContext *c = &(ac->c);
+
+    if (!(c->flags & REDIS_CONNECTED)) {
+        /* Abort connect was not successful. */
+        if (__redisAsyncHandleConnect(ac) != REDIS_OK)
+            return;
+        /* Try again later when the context is still not connected. */
+        if (!(c->flags & REDIS_CONNECTED))
+            return;
+    }
+
+    c->funcs->async_read(ac);
+}
+
+void redisAsyncWrite(redisAsyncContext *ac) {
+    redisContext *c = &(ac->c);
+    int done = 0;
+
+    if (redisBufferWrite(c,&done) == REDIS_ERR) {
+        __redisAsyncDisconnect(ac);
+    } else {
+        /* Continue writing when not done, stop writing otherwise */
+        if (!done)
+            _EL_ADD_WRITE(ac);
+        else
+            _EL_DEL_WRITE(ac);
+
+        /* Always schedule reads after writes */
+        _EL_ADD_READ(ac);
+    }
+}
+
+void redisAsyncHandleWrite(redisAsyncContext *ac) {
+    redisContext *c = &(ac->c);
+
+    if (!(c->flags & REDIS_CONNECTED)) {
+        /* Abort connect was not successful. */
+        if (__redisAsyncHandleConnect(ac) != REDIS_OK)
+            return;
+        /* Try again later when the context is still not connected. */
+        if (!(c->flags & REDIS_CONNECTED))
+            return;
+    }
+
+    c->funcs->async_write(ac);
+}
+
+void redisAsyncHandleTimeout(redisAsyncContext *ac) {
+    redisContext *c = &(ac->c);
+    redisCallback cb;
+
+    if ((c->flags & REDIS_CONNECTED)) {
+        if (ac->replies.head == NULL && ac->sub.replies.head == NULL) {
+            /* Nothing to do - just an idle timeout */
+            return;
+        }
+
+        if (!ac->c.command_timeout ||
+            (!ac->c.command_timeout->tv_sec && !ac->c.command_timeout->tv_usec)) {
+            /* A belated connect timeout arriving, ignore */
+            return;
+        }
+    }
+
+    if (!c->err) {
+        __redisSetError(c, REDIS_ERR_TIMEOUT, "Timeout");
+        __redisAsyncCopyError(ac);
+    }
+
+    if (!(c->flags & REDIS_CONNECTED) && ac->onConnect) {
+        ac->onConnect(ac, REDIS_ERR);
+    }
+
+    while (__redisShiftCallback(&ac->replies, &cb) == REDIS_OK) {
+        __redisRunCallback(ac, &cb, NULL);
+    }
+
+    /**
+     * TODO: Don't automatically sever the connection,
+     * rather, allow to ignore <x> responses before the queue is clear
+     */
+    __redisAsyncDisconnect(ac);
+}
+
+/* Sets a pointer to the first argument and its length starting at p. Returns
+ * the number of bytes to skip to get to the following argument. */
+static const char *nextArgument(const char *start, const char **str, size_t *len) {
+    const char *p = start;
+    if (p[0] != '$') {
+        p = strchr(p,'$');
+        if (p == NULL) return NULL;
+    }
+
+    *len = (int)strtol(p+1,NULL,10);
+    p = strchr(p,'\r');
+    assert(p);
+    *str = p+2;
+    return p+2+(*len)+2;
+}
+
+/* Helper function for the redisAsyncCommand* family of functions. Writes a
+ * formatted command to the output buffer and registers the provided callback
+ * function with the context. */
+static int __redisAsyncCommand(redisAsyncContext *ac, redisCallbackFn *fn, void *privdata, const char *cmd, size_t len) {
+    redisContext *c = &(ac->c);
+    redisCallback cb;
+    struct dict *cbdict;
+    dictEntry *de;
+    redisCallback *existcb;
+    int pvariant, hasnext;
+    const char *cstr, *astr;
+    size_t clen, alen;
+    const char *p;
+    hisds sname;
+    int ret;
+
+    /* Don't accept new commands when the connection is about to be closed. */
+    if (c->flags & (REDIS_DISCONNECTING | REDIS_FREEING)) return REDIS_ERR;
+
+    /* Setup callback */
+    cb.fn = fn;
+    cb.privdata = privdata;
+    cb.pending_subs = 1;
+
+    /* Find out which command will be appended. */
+    p = nextArgument(cmd,&cstr,&clen);
+    assert(p != NULL);
+    hasnext = (p[0] == '$');
+    pvariant = (tolower(cstr[0]) == 'p') ? 1 : 0;
+    cstr += pvariant;
+    clen -= pvariant;
+
+    if (hasnext && strncasecmp(cstr,"subscribe\r\n",11) == 0) {
+        c->flags |= REDIS_SUBSCRIBED;
+
+        /* Add every channel/pattern to the list of subscription callbacks. */
+        while ((p = nextArgument(p,&astr,&alen)) != NULL) {
+            sname = hi_sdsnewlen(astr,alen);
+            if (sname == NULL)
+                goto oom;
+
+            if (pvariant)
+                cbdict = ac->sub.patterns;
+            else
+                cbdict = ac->sub.channels;
+
+            de = dictFind(cbdict,sname);
+
+            if (de != NULL) {
+                existcb = dictGetEntryVal(de);
+                cb.pending_subs = existcb->pending_subs + 1;
+            }
+
+            ret = dictReplace(cbdict,sname,&cb);
+
+            if (ret == 0) hi_sdsfree(sname);
+        }
+    } else if (strncasecmp(cstr,"unsubscribe\r\n",13) == 0) {
+        /* It is only useful to call (P)UNSUBSCRIBE when the context is
+         * subscribed to one or more channels or patterns. */
+        if (!(c->flags & REDIS_SUBSCRIBED)) return REDIS_ERR;
+
+        /* (P)UNSUBSCRIBE does not have its own response: every channel or
+         * pattern that is unsubscribed will receive a message. This means we
+         * should not append a callback function for this command. */
+    } else if (strncasecmp(cstr,"monitor\r\n",9) == 0) {
+        /* Set monitor flag and push callback */
+        c->flags |= REDIS_MONITORING;
+        if (__redisPushCallback(&ac->replies,&cb) != REDIS_OK)
+            goto oom;
+    } else {
+        if (c->flags & REDIS_SUBSCRIBED) {
+            if (__redisPushCallback(&ac->sub.replies,&cb) != REDIS_OK)
+                goto oom;
+        } else {
+            if (__redisPushCallback(&ac->replies,&cb) != REDIS_OK)
+                goto oom;
+        }
+    }
+
+    __redisAppendCommand(c,cmd,len);
+
+    /* Always schedule a write when the write buffer is non-empty */
+    _EL_ADD_WRITE(ac);
+
+    return REDIS_OK;
+oom:
+    __redisSetError(&(ac->c), REDIS_ERR_OOM, "Out of memory");
+    __redisAsyncCopyError(ac);
+    return REDIS_ERR;
+}
+
+int redisvAsyncCommand(redisAsyncContext *ac, redisCallbackFn *fn, void *privdata, const char *format, va_list ap) {
+    char *cmd;
+    int len;
+    int status;
+    len = redisvFormatCommand(&cmd,format,ap);
+
+    /* We don't want to pass -1 or -2 to future functions as a length. */
+    if (len < 0)
+        return REDIS_ERR;
+
+    status = __redisAsyncCommand(ac,fn,privdata,cmd,len);
+    hi_free(cmd);
+    return status;
+}
+
+int redisAsyncCommand(redisAsyncContext *ac, redisCallbackFn *fn, void *privdata, const char *format, ...) {
+    va_list ap;
+    int status;
+    va_start(ap,format);
+    status = redisvAsyncCommand(ac,fn,privdata,format,ap);
+    va_end(ap);
+    return status;
+}
+
+int redisAsyncCommandArgv(redisAsyncContext *ac, redisCallbackFn *fn, void *privdata, int argc, const char **argv, const size_t *argvlen) {
+    hisds cmd;
+    long long len;
+    int status;
+    len = redisFormatSdsCommandArgv(&cmd,argc,argv,argvlen);
+    if (len < 0)
+        return REDIS_ERR;
+    status = __redisAsyncCommand(ac,fn,privdata,cmd,len);
+    hi_sdsfree(cmd);
+    return status;
+}
+
+int redisAsyncFormattedCommand(redisAsyncContext *ac, redisCallbackFn *fn, void *privdata, const char *cmd, size_t len) {
+    int status = __redisAsyncCommand(ac,fn,privdata,cmd,len);
+    return status;
+}
+
+redisAsyncPushFn *redisAsyncSetPushCallback(redisAsyncContext *ac, redisAsyncPushFn *fn) {
+    redisAsyncPushFn *old = ac->push_cb;
+    ac->push_cb = fn;
+    return old;
+}
+
+int redisAsyncSetTimeout(redisAsyncContext *ac, struct timeval tv) {
+    if (!ac->c.command_timeout) {
+        ac->c.command_timeout = hi_calloc(1, sizeof(tv));
+        if (ac->c.command_timeout == NULL) {
+            __redisSetError(&ac->c, REDIS_ERR_OOM, "Out of memory");
+            __redisAsyncCopyError(ac);
+            return REDIS_ERR;
+        }
+    }
+
+    if (tv.tv_sec != ac->c.command_timeout->tv_sec ||
+        tv.tv_usec != ac->c.command_timeout->tv_usec)
+    {
+        *ac->c.command_timeout = tv;
+    }
+
+    return REDIS_OK;
+}

src/async.h

@@ -0,0 +1,147 @@
+/*
+ * Copyright (c) 2009-2011, Salvatore Sanfilippo <antirez at gmail dot com>
+ * Copyright (c) 2010-2011, Pieter Noordhuis <pcnoordhuis at gmail dot com>
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __HIREDIS_ASYNC_H
+#define __HIREDIS_ASYNC_H
+#include "hiredis.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct redisAsyncContext; /* need forward declaration of redisAsyncContext */
+struct dict; /* dictionary header is included in async.c */
+
+/* Reply callback prototype and container */
+typedef void (redisCallbackFn)(struct redisAsyncContext*, void*, void*);
+typedef struct redisCallback {
+    struct redisCallback *next; /* simple singly linked list */
+    redisCallbackFn *fn;
+    int pending_subs;
+    void *privdata;
+} redisCallback;
+
+/* List of callbacks for either regular replies or pub/sub */
+typedef struct redisCallbackList {
+    redisCallback *head, *tail;
+} redisCallbackList;
+
+/* Connection callback prototypes */
+typedef void (redisDisconnectCallback)(const struct redisAsyncContext*, int status);
+typedef void (redisConnectCallback)(const struct redisAsyncContext*, int status);
+typedef void(redisTimerCallback)(void *timer, void *privdata);
+
+/* Context for an async connection to Redis */
+typedef struct redisAsyncContext {
+    /* Hold the regular context, so it can be realloc'ed. */
+    redisContext c;
+
+    /* Setup error flags so they can be used directly. */
+    int err;
+    char *errstr;
+
+    /* Not used by hiredis */
+    void *data;
+    void (*dataCleanup)(void *privdata);
+
+    /* Event library data and hooks */
+    struct {
+        void *data;
+
+        /* Hooks that are called when the library expects to start
+         * reading/writing. These functions should be idempotent. */
+        void (*addRead)(void *privdata);
+        void (*delRead)(void *privdata);
+        void (*addWrite)(void *privdata);
+        void (*delWrite)(void *privdata);
+        void (*cleanup)(void *privdata);
+        void (*scheduleTimer)(void *privdata, struct timeval tv);
+    } ev;
+
+    /* Called when either the connection is terminated due to an error or per
+     * user request. The status is set accordingly (REDIS_OK, REDIS_ERR). */
+    redisDisconnectCallback *onDisconnect;
+
+    /* Called when the first write event was received. */
+    redisConnectCallback *onConnect;
+
+    /* Regular command callbacks */
+    redisCallbackList replies;
+
+    /* Address used for connect() */
+    struct sockaddr *saddr;
+    size_t addrlen;
+
+    /* Subscription callbacks */
+    struct {
+        redisCallbackList replies;
+        struct dict *channels;
+        struct dict *patterns;
+    } sub;
+
+    /* Any configured RESP3 PUSH handler */
+    redisAsyncPushFn *push_cb;
+} redisAsyncContext;
+
+/* Functions that proxy to hiredis */
+redisAsyncContext *redisAsyncConnectWithOptions(const redisOptions *options);
+redisAsyncContext *redisAsyncConnect(const char *ip, int port);
+redisAsyncContext *redisAsyncConnectBind(const char *ip, int port, const char *source_addr);
+redisAsyncContext *redisAsyncConnectBindWithReuse(const char *ip, int port,
+                                                  const char *source_addr);
+redisAsyncContext *redisAsyncConnectUnix(const char *path);
+int redisAsyncSetConnectCallback(redisAsyncContext *ac, redisConnectCallback *fn);
+int redisAsyncSetDisconnectCallback(redisAsyncContext *ac, redisDisconnectCallback *fn);
+
+redisAsyncPushFn *redisAsyncSetPushCallback(redisAsyncContext *ac, redisAsyncPushFn *fn);
+int redisAsyncSetTimeout(redisAsyncContext *ac, struct timeval tv);
+void redisAsyncDisconnect(redisAsyncContext *ac);
+void redisAsyncFree(redisAsyncContext *ac);
+
+/* Handle read/write events */
+void redisAsyncHandleRead(redisAsyncContext *ac);
+void redisAsyncHandleWrite(redisAsyncContext *ac);
+void redisAsyncHandleTimeout(redisAsyncContext *ac);
+void redisAsyncRead(redisAsyncContext *ac);
+void redisAsyncWrite(redisAsyncContext *ac);
+
+/* Command functions for an async context. Write the command to the
+ * output buffer and register the provided callback. */
+int redisvAsyncCommand(redisAsyncContext *ac, redisCallbackFn *fn, void *privdata, const char *format, va_list ap);
+int redisAsyncCommand(redisAsyncContext *ac, redisCallbackFn *fn, void *privdata, const char *format, ...);
+int redisAsyncCommandArgv(redisAsyncContext *ac, redisCallbackFn *fn, void *privdata, int argc, const char **argv, const size_t *argvlen);
+int redisAsyncFormattedCommand(redisAsyncContext *ac, redisCallbackFn *fn, void *privdata, const char *cmd, size_t len);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

src/async_private.h

@@ -0,0 +1,75 @@
+/*
+ * Copyright (c) 2009-2011, Salvatore Sanfilippo <antirez at gmail dot com>
+ * Copyright (c) 2010-2011, Pieter Noordhuis <pcnoordhuis at gmail dot com>
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __HIREDIS_ASYNC_PRIVATE_H
+#define __HIREDIS_ASYNC_PRIVATE_H
+
+#define _EL_ADD_READ(ctx)                                         \
+    do {                                                          \
+        refreshTimeout(ctx);                                      \
+        if ((ctx)->ev.addRead) (ctx)->ev.addRead((ctx)->ev.data); \
+    } while (0)
+#define _EL_DEL_READ(ctx) do { \
+        if ((ctx)->ev.delRead) (ctx)->ev.delRead((ctx)->ev.data); \
+    } while(0)
+#define _EL_ADD_WRITE(ctx)                                          \
+    do {                                                            \
+        refreshTimeout(ctx);                                        \
+        if ((ctx)->ev.addWrite) (ctx)->ev.addWrite((ctx)->ev.data); \
+    } while (0)
+#define _EL_DEL_WRITE(ctx) do { \
+        if ((ctx)->ev.delWrite) (ctx)->ev.delWrite((ctx)->ev.data); \
+    } while(0)
+#define _EL_CLEANUP(ctx) do { \
+        if ((ctx)->ev.cleanup) (ctx)->ev.cleanup((ctx)->ev.data); \
+        ctx->ev.cleanup = NULL; \
+    } while(0)
+
+static inline void refreshTimeout(redisAsyncContext *ctx) {
+    #define REDIS_TIMER_ISSET(tvp) \
+        (tvp && ((tvp)->tv_sec || (tvp)->tv_usec))
+
+    #define REDIS_EL_TIMER(ac, tvp) \
+        if ((ac)->ev.scheduleTimer && REDIS_TIMER_ISSET(tvp)) { \
+            (ac)->ev.scheduleTimer((ac)->ev.data, *(tvp)); \
+        }
+
+    if (ctx->c.flags & REDIS_CONNECTED) {
+        REDIS_EL_TIMER(ctx, ctx->c.command_timeout);
+    } else {
+        REDIS_EL_TIMER(ctx, ctx->c.connect_timeout);
+    }
+}
+
+void __redisAsyncDisconnect(redisAsyncContext *ac);
+void redisProcessCallbacks(redisAsyncContext *ac);
+
+#endif  /* __HIREDIS_ASYNC_PRIVATE_H */

src/dict.c

@@ -0,0 +1,343 @@
+/* Hash table implementation.
+ *
+ * This file implements in memory hash tables with insert/del/replace/find/
+ * get-random-element operations. Hash tables will auto resize if needed
+ * tables of power of two in size are used, collisions are handled by
+ * chaining. See the source code for more information... :)
+ *
+ * Copyright (c) 2006-2010, Salvatore Sanfilippo <antirez at gmail dot com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "fmacros.h"
+#include "alloc.h"
+#include <stdlib.h>
+#include <assert.h>
+#include <limits.h>
+#include "dict.h"
+
+/* -------------------------- private prototypes ---------------------------- */
+
+static int _dictExpandIfNeeded(dict *ht);
+static unsigned long _dictNextPower(unsigned long size);
+static int _dictKeyIndex(dict *ht, const void *key);
+static int _dictInit(dict *ht, dictType *type, void *privDataPtr);
+
+/* -------------------------- hash functions -------------------------------- */
+
+/* Generic hash function (a popular one from Bernstein).
+ * I tested a few and this was the best. */
+static unsigned int dictGenHashFunction(const unsigned char *buf, int len) {
+    unsigned int hash = 5381;
+
+    while (len--)
+        hash = ((hash << 5) + hash) + (*buf++); /* hash * 33 + c */
+    return hash;
+}
+
+/* ----------------------------- API implementation ------------------------- */
+
+/* Reset an hashtable already initialized with ht_init().
+ * NOTE: This function should only called by ht_destroy(). */
+static void _dictReset(dict *ht) {
+    ht->table = NULL;
+    ht->size = 0;
+    ht->sizemask = 0;
+    ht->used = 0;
+}
+
+/* Create a new hash table */
+static dict *dictCreate(dictType *type, void *privDataPtr) {
+    dict *ht = hi_malloc(sizeof(*ht));
+    if (ht == NULL)
+        return NULL;
+
+    _dictInit(ht,type,privDataPtr);
+    return ht;
+}
+
+/* Initialize the hash table */
+static int _dictInit(dict *ht, dictType *type, void *privDataPtr) {
+    _dictReset(ht);
+    ht->type = type;
+    ht->privdata = privDataPtr;
+    return DICT_OK;
+}
+
+/* Expand or create the hashtable */
+static int dictExpand(dict *ht, unsigned long size) {
+    dict n; /* the new hashtable */
+    unsigned long realsize = _dictNextPower(size), i;
+
+    /* the size is invalid if it is smaller than the number of
+     * elements already inside the hashtable */
+    if (ht->used > size)
+        return DICT_ERR;
+
+    _dictInit(&n, ht->type, ht->privdata);
+    n.size = realsize;
+    n.sizemask = realsize-1;
+    n.table = hi_calloc(realsize,sizeof(dictEntry*));
+    if (n.table == NULL)
+        return DICT_ERR;
+
+    /* Copy all the elements from the old to the new table:
+     * note that if the old hash table is empty ht->size is zero,
+     * so dictExpand just creates an hash table. */
+    n.used = ht->used;
+    for (i = 0; i < ht->size && ht->used > 0; i++) {
+        dictEntry *he, *nextHe;
+
+        if (ht->table[i] == NULL) continue;
+
+        /* For each hash entry on this slot... */
+        he = ht->table[i];
+        while(he) {
+            unsigned int h;
+
+            nextHe = he->next;
+            /* Get the new element index */
+            h = dictHashKey(ht, he->key) & n.sizemask;
+            he->next = n.table[h];
+            n.table[h] = he;
+            ht->used--;
+            /* Pass to the next element */
+            he = nextHe;
+        }
+    }
+    assert(ht->used == 0);
+    hi_free(ht->table);
+
+    /* Remap the new hashtable in the old */
+    *ht = n;
+    return DICT_OK;
+}
+
+/* Add an element to the target hash table */
+static int dictAdd(dict *ht, void *key, void *val) {
+    int index;
+    dictEntry *entry;
+
+    /* Get the index of the new element, or -1 if
+     * the element already exists. */
+    if ((index = _dictKeyIndex(ht, key)) == -1)
+        return DICT_ERR;
+
+    /* Allocates the memory and stores key */
+    entry = hi_malloc(sizeof(*entry));
+    if (entry == NULL)
+        return DICT_ERR;
+
+    entry->next = ht->table[index];
+    ht->table[index] = entry;
+
+    /* Set the hash entry fields. */
+    dictSetHashKey(ht, entry, key);
+    dictSetHashVal(ht, entry, val);
+    ht->used++;
+    return DICT_OK;
+}
+
+/* Add an element, discarding the old if the key already exists.
+ * Return 1 if the key was added from scratch, 0 if there was already an
+ * element with such key and dictReplace() just performed a value update
+ * operation. */
+static int dictReplace(dict *ht, void *key, void *val) {
+    dictEntry *entry, auxentry;
+
+    /* Try to add the element. If the key
+     * does not exists dictAdd will succeed. */
+    if (dictAdd(ht, key, val) == DICT_OK)
+        return 1;
+    /* It already exists, get the entry */
+    entry = dictFind(ht, key);
+    if (entry == NULL)
+        return 0;
+
+    /* Free the old value and set the new one */
+    /* Set the new value and free the old one. Note that it is important
+     * to do that in this order, as the value may just be exactly the same
+     * as the previous one. In this context, think to reference counting,
+     * you want to increment (set), and then decrement (free), and not the
+     * reverse. */
+    auxentry = *entry;
+    dictSetHashVal(ht, entry, val);
+    dictFreeEntryVal(ht, &auxentry);
+    return 0;
+}
+
+/* Search and remove an element */
+static int dictDelete(dict *ht, const void *key) {
+    unsigned int h;
+    dictEntry *de, *prevde;
+
+    if (ht->size == 0)
+        return DICT_ERR;
+    h = dictHashKey(ht, key) & ht->sizemask;
+    de = ht->table[h];
+
+    prevde = NULL;
+    while(de) {
+        if (dictCompareHashKeys(ht,key,de->key)) {
+            /* Unlink the element from the list */
+            if (prevde)
+                prevde->next = de->next;
+            else
+                ht->table[h] = de->next;
+
+            dictFreeEntryKey(ht,de);
+            dictFreeEntryVal(ht,de);
+            hi_free(de);
+            ht->used--;
+            return DICT_OK;
+        }
+        prevde = de;
+        de = de->next;
+    }
+    return DICT_ERR; /* not found */
+}
+
+/* Destroy an entire hash table */
+static int _dictClear(dict *ht) {
+    unsigned long i;
+
+    /* Free all the elements */
+    for (i = 0; i < ht->size && ht->used > 0; i++) {
+        dictEntry *he, *nextHe;
+
+        if ((he = ht->table[i]) == NULL) continue;
+        while(he) {
+            nextHe = he->next;
+            dictFreeEntryKey(ht, he);
+            dictFreeEntryVal(ht, he);
+            hi_free(he);
+            ht->used--;
+            he = nextHe;
+        }
+    }
+    /* Free the table and the allocated cache structure */
+    hi_free(ht->table);
+    /* Re-initialize the table */
+    _dictReset(ht);
+    return DICT_OK; /* never fails */
+}
+
+/* Clear & Release the hash table */
+static void dictRelease(dict *ht) {
+    _dictClear(ht);
+    hi_free(ht);
+}
+
+static dictEntry *dictFind(dict *ht, const void *key) {
+    dictEntry *he;
+    unsigned int h;
+
+    if (ht->size == 0) return NULL;
+    h = dictHashKey(ht, key) & ht->sizemask;
+    he = ht->table[h];
+    while(he) {
+        if (dictCompareHashKeys(ht, key, he->key))
+            return he;
+        he = he->next;
+    }
+    return NULL;
+}
+
+static void dictInitIterator(dictIterator *iter, dict *ht) {
+    iter->ht = ht;
+    iter->index = -1;
+    iter->entry = NULL;
+    iter->nextEntry = NULL;
+}
+
+static dictEntry *dictNext(dictIterator *iter) {
+    while (1) {
+        if (iter->entry == NULL) {
+            iter->index++;
+            if (iter->index >=
+                    (signed)iter->ht->size) break;
+            iter->entry = iter->ht->table[iter->index];
+        } else {
+            iter->entry = iter->nextEntry;
+        }
+        if (iter->entry) {
+            /* We need to save the 'next' here, the iterator user
+             * may delete the entry we are returning. */
+            iter->nextEntry = iter->entry->next;
+            return iter->entry;
+        }
+    }
+    return NULL;
+}
+
+/* ------------------------- private functions ------------------------------ */
+
+/* Expand the hash table if needed */
+static int _dictExpandIfNeeded(dict *ht) {
+    /* If the hash table is empty expand it to the initial size,
+     * if the table is "full" double its size. */
+    if (ht->size == 0)
+        return dictExpand(ht, DICT_HT_INITIAL_SIZE);
+    if (ht->used == ht->size)
+        return dictExpand(ht, ht->size*2);
+    return DICT_OK;
+}
+
+/* Our hash table capability is a power of two */
+static unsigned long _dictNextPower(unsigned long size) {
+    unsigned long i = DICT_HT_INITIAL_SIZE;
+
+    if (size >= LONG_MAX) return LONG_MAX;
+    while(1) {
+        if (i >= size)
+            return i;
+        i *= 2;
+    }
+}
+
+/* Returns the index of a free slot that can be populated with
+ * an hash entry for the given 'key'.
+ * If the key already exists, -1 is returned. */
+static int _dictKeyIndex(dict *ht, const void *key) {
+    unsigned int h;
+    dictEntry *he;
+
+    /* Expand the hashtable if needed */
+    if (_dictExpandIfNeeded(ht) == DICT_ERR)
+        return -1;
+    /* Compute the key hash value */
+    h = dictHashKey(ht, key) & ht->sizemask;
+    /* Search if this slot does not already contain the given key */
+    he = ht->table[h];
+    while(he) {
+        if (dictCompareHashKeys(ht, key, he->key))
+            return -1;
+        he = he->next;
+    }
+    return h;
+}
+

src/dict.h

@@ -0,0 +1,125 @@
+/* Hash table implementation.
+ *
+ * This file implements in memory hash tables with insert/del/replace/find/
+ * get-random-element operations. Hash tables will auto resize if needed
+ * tables of power of two in size are used, collisions are handled by
+ * chaining. See the source code for more information... :)
+ *
+ * Copyright (c) 2006-2010, Salvatore Sanfilippo <antirez at gmail dot com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __DICT_H
+#define __DICT_H
+
+#define DICT_OK 0
+#define DICT_ERR 1
+
+/* Unused arguments generate annoying warnings... */
+#define DICT_NOTUSED(V) ((void) V)
+
+typedef struct dictEntry {
+    void *key;
+    void *val;
+    struct dictEntry *next;
+} dictEntry;
+
+typedef struct dictType {
+    unsigned int (*hashFunction)(const void *key);
+    void *(*keyDup)(void *privdata, const void *key);
+    void *(*valDup)(void *privdata, const void *obj);
+    int (*keyCompare)(void *privdata, const void *key1, const void *key2);
+    void (*keyDestructor)(void *privdata, void *key);
+    void (*valDestructor)(void *privdata, void *obj);
+} dictType;
+
+typedef struct dict {
+    dictEntry **table;
+    dictType *type;
+    unsigned long size;
+    unsigned long sizemask;
+    unsigned long used;
+    void *privdata;
+} dict;
+
+typedef struct dictIterator {
+    dict *ht;
+    int index;
+    dictEntry *entry, *nextEntry;
+} dictIterator;
+
+/* This is the initial size of every hash table */
+#define DICT_HT_INITIAL_SIZE     4
+
+/* ------------------------------- Macros ------------------------------------*/
+#define dictFreeEntryVal(ht, entry) \
+    if ((ht)->type->valDestructor) \
+        (ht)->type->valDestructor((ht)->privdata, (entry)->val)
+
+#define dictSetHashVal(ht, entry, _val_) do { \
+    if ((ht)->type->valDup) \
+        entry->val = (ht)->type->valDup((ht)->privdata, _val_); \
+    else \
+        entry->val = (_val_); \
+} while(0)
+
+#define dictFreeEntryKey(ht, entry) \
+    if ((ht)->type->keyDestructor) \
+        (ht)->type->keyDestructor((ht)->privdata, (entry)->key)
+
+#define dictSetHashKey(ht, entry, _key_) do { \
+    if ((ht)->type->keyDup) \
+        entry->key = (ht)->type->keyDup((ht)->privdata, _key_); \
+    else \
+        entry->key = (_key_); \
+} while(0)
+
+#define dictCompareHashKeys(ht, key1, key2) \
+    (((ht)->type->keyCompare) ? \
+        (ht)->type->keyCompare((ht)->privdata, key1, key2) : \
+        (key1) == (key2))
+
+#define dictHashKey(ht, key) (ht)->type->hashFunction(key)
+
+#define dictGetEntryKey(he) ((he)->key)
+#define dictGetEntryVal(he) ((he)->val)
+#define dictSlots(ht) ((ht)->size)
+#define dictSize(ht) ((ht)->used)
+
+/* API */
+static unsigned int dictGenHashFunction(const unsigned char *buf, int len);
+static dict *dictCreate(dictType *type, void *privDataPtr);
+static int dictExpand(dict *ht, unsigned long size);
+static int dictAdd(dict *ht, void *key, void *val);
+static int dictReplace(dict *ht, void *key, void *val);
+static int dictDelete(dict *ht, const void *key);
+static void dictRelease(dict *ht);
+static dictEntry * dictFind(dict *ht, const void *key);
+static void dictInitIterator(dictIterator *iter, dict *ht);
+static dictEntry *dictNext(dictIterator *iter);
+
+#endif /* __DICT_H */

src/fmacros.h

@@ -0,0 +1,14 @@
+#ifndef __HIREDIS_FMACRO_H
+#define __HIREDIS_FMACRO_H
+
+#ifndef _AIX
+#define _XOPEN_SOURCE 600
+#define _POSIX_C_SOURCE 200112L
+#endif
+
+#if defined(__APPLE__) && defined(__MACH__)
+/* Enable TCP_KEEPALIVE */
+#define _DARWIN_C_SOURCE
+#endif
+
+#endif

src/hiredis.h

@@ -0,0 +1,348 @@
+/*
+ * Copyright (c) 2009-2011, Salvatore Sanfilippo <antirez at gmail dot com>
+ * Copyright (c) 2010-2014, Pieter Noordhuis <pcnoordhuis at gmail dot com>
+ * Copyright (c) 2015, Matt Stancliff <matt at genges dot com>,
+ *                     Jan-Erik Rediger <janerik at fnordig dot com>
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __HIREDIS_H
+#define __HIREDIS_H
+#include "read.h"
+#include <stdarg.h> /* for va_list */
+#ifndef _MSC_VER
+#include <sys/time.h> /* for struct timeval */
+#else
+struct timeval; /* forward declaration */
+typedef long long ssize_t;
+#endif
+#include <stdint.h> /* uintXX_t, etc */
+#include "sds.h" /* for hisds */
+#include "alloc.h" /* for allocation wrappers */
+
+#define HIREDIS_MAJOR 1
+#define HIREDIS_MINOR 0
+#define HIREDIS_PATCH 3
+#define HIREDIS_SONAME 1.0.3-dev
+
+/* Connection type can be blocking or non-blocking and is set in the
+ * least significant bit of the flags field in redisContext. */
+#define REDIS_BLOCK 0x1
+
+/* Connection may be disconnected before being free'd. The second bit
+ * in the flags field is set when the context is connected. */
+#define REDIS_CONNECTED 0x2
+
+/* The async API might try to disconnect cleanly and flush the output
+ * buffer and read all subsequent replies before disconnecting.
+ * This flag means no new commands can come in and the connection
+ * should be terminated once all replies have been read. */
+#define REDIS_DISCONNECTING 0x4
+
+/* Flag specific to the async API which means that the context should be clean
+ * up as soon as possible. */
+#define REDIS_FREEING 0x8
+
+/* Flag that is set when an async callback is executed. */
+#define REDIS_IN_CALLBACK 0x10
+
+/* Flag that is set when the async context has one or more subscriptions. */
+#define REDIS_SUBSCRIBED 0x20
+
+/* Flag that is set when monitor mode is active */
+#define REDIS_MONITORING 0x40
+
+/* Flag that is set when we should set SO_REUSEADDR before calling bind() */
+#define REDIS_REUSEADDR 0x80
+
+/* Flag that is set when the async connection supports push replies. */
+#define REDIS_SUPPORTS_PUSH 0x100
+
+/**
+ * Flag that indicates the user does not want the context to
+ * be automatically freed upon error
+ */
+#define REDIS_NO_AUTO_FREE 0x200
+
+/* Flag that indicates the user does not want replies to be automatically freed */
+#define REDIS_NO_AUTO_FREE_REPLIES 0x400
+
+#define REDIS_KEEPALIVE_INTERVAL 15 /* seconds */
+
+/* number of times we retry to connect in the case of EADDRNOTAVAIL and
+ * SO_REUSEADDR is being used. */
+#define REDIS_CONNECT_RETRIES  10
+
+/* Forward declarations for structs defined elsewhere */
+struct redisAsyncContext;
+struct redisContext;
+
+/* RESP3 push helpers and callback prototypes */
+#define redisIsPushReply(r) (((redisReply*)(r))->type == REDIS_REPLY_PUSH)
+typedef void (redisPushFn)(void *, void *);
+typedef void (redisAsyncPushFn)(struct redisAsyncContext *, void *);
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* This is the reply object returned by redisCommand() */
+typedef struct redisReply {
+    int type; /* REDIS_REPLY_* */
+    long long integer; /* The integer when type is REDIS_REPLY_INTEGER */
+    double dval; /* The double when type is REDIS_REPLY_DOUBLE */
+    size_t len; /* Length of string */
+    char *str; /* Used for REDIS_REPLY_ERROR, REDIS_REPLY_STRING
+                  REDIS_REPLY_VERB, REDIS_REPLY_DOUBLE (in additional to dval),
+                  and REDIS_REPLY_BIGNUM. */
+    char vtype[4]; /* Used for REDIS_REPLY_VERB, contains the null
+                      terminated 3 character content type, such as "txt". */
+    size_t elements; /* number of elements, for REDIS_REPLY_ARRAY */
+    struct redisReply **element; /* elements vector for REDIS_REPLY_ARRAY */
+} redisReply;
+
+redisReader *redisReaderCreate(void);
+
+/* Function to free the reply objects hiredis returns by default. */
+void freeReplyObject(void *reply);
+
+/* Functions to format a command according to the protocol. */
+int redisvFormatCommand(char **target, const char *format, va_list ap);
+int redisFormatCommand(char **target, const char *format, ...);
+long long redisFormatCommandArgv(char **target, int argc, const char **argv, const size_t *argvlen);
+long long redisFormatSdsCommandArgv(hisds *target, int argc, const char ** argv, const size_t *argvlen);
+void redisFreeCommand(char *cmd);
+void redisFreeSdsCommand(hisds cmd);
+
+enum redisConnectionType {
+    REDIS_CONN_TCP,
+    REDIS_CONN_UNIX,
+    REDIS_CONN_USERFD
+};
+
+struct redisSsl;
+
+#define REDIS_OPT_NONBLOCK 0x01
+#define REDIS_OPT_REUSEADDR 0x02
+
+/**
+ * Don't automatically free the async object on a connection failure,
+ * or other implicit conditions. Only free on an explicit call to disconnect() or free()
+ */
+#define REDIS_OPT_NOAUTOFREE 0x04
+
+/* Don't automatically intercept and free RESP3 PUSH replies. */
+#define REDIS_OPT_NO_PUSH_AUTOFREE 0x08
+
+/**
+ * Don't automatically free replies
+ */
+#define REDIS_OPT_NOAUTOFREEREPLIES 0x10
+
+/* In Unix systems a file descriptor is a regular signed int, with -1
+ * representing an invalid descriptor. In Windows it is a SOCKET
+ * (32- or 64-bit unsigned integer depending on the architecture), where
+ * all bits set (~0) is INVALID_SOCKET.  */
+#ifndef _WIN32
+typedef int redisFD;
+#define REDIS_INVALID_FD -1
+#else
+#ifdef _WIN64
+typedef unsigned long long redisFD; /* SOCKET = 64-bit UINT_PTR */
+#else
+typedef unsigned long redisFD;      /* SOCKET = 32-bit UINT_PTR */
+#endif
+#define REDIS_INVALID_FD ((redisFD)(~0)) /* INVALID_SOCKET */
+#endif
+
+typedef struct {
+    /*
+     * the type of connection to use. This also indicates which
+     * `endpoint` member field to use
+     */
+    int type;
+    /* bit field of REDIS_OPT_xxx */
+    int options;
+    /* timeout value for connect operation. If NULL, no timeout is used */
+    const struct timeval *connect_timeout;
+    /* timeout value for commands. If NULL, no timeout is used.  This can be
+     * updated at runtime with redisSetTimeout/redisAsyncSetTimeout. */
+    const struct timeval *command_timeout;
+    union {
+        /** use this field for tcp/ip connections */
+        struct {
+            const char *source_addr;
+            const char *ip;
+            int port;
+        } tcp;
+        /** use this field for unix domain sockets */
+        const char *unix_socket;
+        /**
+         * use this field to have hiredis operate an already-open
+         * file descriptor */
+        redisFD fd;
+    } endpoint;
+
+    /* Optional user defined data/destructor */
+    void *privdata;
+    void (*free_privdata)(void *);
+
+    /* A user defined PUSH message callback */
+    redisPushFn *push_cb;
+    redisAsyncPushFn *async_push_cb;
+} redisOptions;
+
+/**
+ * Helper macros to initialize options to their specified fields.
+ */
+#define REDIS_OPTIONS_SET_TCP(opts, ip_, port_) \
+    (opts)->type = REDIS_CONN_TCP; \
+    (opts)->endpoint.tcp.ip = ip_; \
+    (opts)->endpoint.tcp.port = port_;
+
+#define REDIS_OPTIONS_SET_UNIX(opts, path) \
+    (opts)->type = REDIS_CONN_UNIX;        \
+    (opts)->endpoint.unix_socket = path;
+
+#define REDIS_OPTIONS_SET_PRIVDATA(opts, data, dtor) \
+    (opts)->privdata = data;                         \
+    (opts)->free_privdata = dtor;                    \
+
+typedef struct redisContextFuncs {
+    void (*free_privctx)(void *);
+    void (*async_read)(struct redisAsyncContext *);
+    void (*async_write)(struct redisAsyncContext *);
+    ssize_t (*read)(struct redisContext *, char *, size_t);
+    ssize_t (*write)(struct redisContext *);
+} redisContextFuncs;
+
+/* Context for a connection to Redis */
+typedef struct redisContext {
+    const redisContextFuncs *funcs;   /* Function table */
+
+    int err; /* Error flags, 0 when there is no error */
+    char errstr[128]; /* String representation of error when applicable */
+    redisFD fd;
+    int flags;
+    char *obuf; /* Write buffer */
+    redisReader *reader; /* Protocol reader */
+
+    enum redisConnectionType connection_type;
+    struct timeval *connect_timeout;
+    struct timeval *command_timeout;
+
+    struct {
+        char *host;
+        char *source_addr;
+        int port;
+    } tcp;
+
+    struct {
+        char *path;
+    } unix_sock;
+
+    /* For non-blocking   */
+    struct sockaddr *saddr;
+    size_t addrlen;
+
+    /* Optional data and corresponding destructor users can use to provide
+     * context to a given redisContext.  Not used by hiredis. */
+    void *privdata;
+    void (*free_privdata)(void *);
+
+    /* Internal context pointer presently used by hiredis to manage
+     * SSL connections. */
+    void *privctx;
+
+    /* An optional RESP3 PUSH handler */
+    redisPushFn *push_cb;
+} redisContext;
+
+redisContext *redisConnectWithOptions(const redisOptions *options);
+redisContext *redisConnect(const char *ip, int port);
+redisContext *redisConnectWithTimeout(const char *ip, int port, const struct timeval tv);
+redisContext *redisConnectNonBlock(const char *ip, int port);
+redisContext *redisConnectBindNonBlock(const char *ip, int port,
+                                       const char *source_addr);
+redisContext *redisConnectBindNonBlockWithReuse(const char *ip, int port,
+                                                const char *source_addr);
+redisContext *redisConnectUnix(const char *path);
+redisContext *redisConnectUnixWithTimeout(const char *path, const struct timeval tv);
+redisContext *redisConnectUnixNonBlock(const char *path);
+redisContext *redisConnectFd(redisFD fd);
+
+/**
+ * Reconnect the given context using the saved information.
+ *
+ * This re-uses the exact same connect options as in the initial connection.
+ * host, ip (or path), timeout and bind address are reused,
+ * flags are used unmodified from the existing context.
+ *
+ * Returns REDIS_OK on successful connect or REDIS_ERR otherwise.
+ */
+int redisReconnect(redisContext *c);
+
+redisPushFn *redisSetPushCallback(redisContext *c, redisPushFn *fn);
+int redisSetTimeout(redisContext *c, const struct timeval tv);
+int redisEnableKeepAlive(redisContext *c);
+void redisFree(redisContext *c);
+redisFD redisFreeKeepFd(redisContext *c);
+int redisBufferRead(redisContext *c);
+int redisBufferWrite(redisContext *c, int *done);
+
+/* In a blocking context, this function first checks if there are unconsumed
+ * replies to return and returns one if so. Otherwise, it flushes the output
+ * buffer to the socket and reads until it has a reply. In a non-blocking
+ * context, it will return unconsumed replies until there are no more. */
+int redisGetReply(redisContext *c, void **reply);
+int redisGetReplyFromReader(redisContext *c, void **reply);
+
+/* Write a formatted command to the output buffer. Use these functions in blocking mode
+ * to get a pipeline of commands. */
+int redisAppendFormattedCommand(redisContext *c, const char *cmd, size_t len);
+
+/* Write a command to the output buffer. Use these functions in blocking mode
+ * to get a pipeline of commands. */
+int redisvAppendCommand(redisContext *c, const char *format, va_list ap);
+int redisAppendCommand(redisContext *c, const char *format, ...);
+int redisAppendCommandArgv(redisContext *c, int argc, const char **argv, const size_t *argvlen);
+
+/* Issue a command to Redis. In a blocking context, it is identical to calling
+ * redisAppendCommand, followed by redisGetReply. The function will return
+ * NULL if there was an error in performing the request, otherwise it will
+ * return the reply. In a non-blocking context, it is identical to calling
+ * only redisAppendCommand and will always return NULL. */
+void *redisvCommand(redisContext *c, const char *format, va_list ap);
+void *redisCommand(redisContext *c, const char *format, ...);
+void *redisCommandArgv(redisContext *c, int argc, const char **argv, const size_t *argvlen);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

src/hiredis_ssl.h

@@ -0,0 +1,129 @@
+
+/*
+ * Copyright (c) 2019, Redis Labs
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __HIREDIS_SSL_H
+#define __HIREDIS_SSL_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* This is the underlying struct for SSL in ssl.h, which is not included to
+ * keep build dependencies short here.
+ */
+struct ssl_st;
+
+/* A wrapper around OpenSSL SSL_CTX to allow easy SSL use without directly
+ * calling OpenSSL.
+ */
+typedef struct redisSSLContext redisSSLContext;
+
+/**
+ * Initialization errors that redisCreateSSLContext() may return.
+ */
+
+typedef enum {
+    REDIS_SSL_CTX_NONE = 0,                     /* No Error */
+    REDIS_SSL_CTX_CREATE_FAILED,                /* Failed to create OpenSSL SSL_CTX */
+    REDIS_SSL_CTX_CERT_KEY_REQUIRED,            /* Client cert and key must both be specified or skipped */
+    REDIS_SSL_CTX_CA_CERT_LOAD_FAILED,          /* Failed to load CA Certificate or CA Path */
+    REDIS_SSL_CTX_CLIENT_CERT_LOAD_FAILED,      /* Failed to load client certificate */
+    REDIS_SSL_CTX_PRIVATE_KEY_LOAD_FAILED,      /* Failed to load private key */
+    REDIS_SSL_CTX_OS_CERTSTORE_OPEN_FAILED,     /* Failed to open system certifcate store */
+    REDIS_SSL_CTX_OS_CERT_ADD_FAILED            /* Failed to add CA certificates obtained from system to the SSL context */
+} redisSSLContextError;
+
+/**
+ * Return the error message corresponding with the specified error code.
+ */
+
+const char *redisSSLContextGetError(redisSSLContextError error);
+
+/**
+ * Helper function to initialize the OpenSSL library.
+ *
+ * OpenSSL requires one-time initialization before it can be used. Callers should
+ * call this function only once, and only if OpenSSL is not directly initialized
+ * elsewhere.
+ */
+int redisInitOpenSSL(void);
+
+/**
+ * Helper function to initialize an OpenSSL context that can be used
+ * to initiate SSL connections.
+ *
+ * cacert_filename is an optional name of a CA certificate/bundle file to load
+ * and use for validation.
+ *
+ * capath is an optional directory path where trusted CA certificate files are
+ * stored in an OpenSSL-compatible structure.
+ *
+ * cert_filename and private_key_filename are optional names of a client side
+ * certificate and private key files to use for authentication. They need to
+ * be both specified or omitted.
+ *
+ * server_name is an optional and will be used as a server name indication
+ * (SNI) TLS extension.
+ *
+ * If error is non-null, it will be populated in case the context creation fails
+ * (returning a NULL).
+ */
+
+redisSSLContext *redisCreateSSLContext(const char *cacert_filename, const char *capath,
+        const char *cert_filename, const char *private_key_filename,
+        const char *server_name, redisSSLContextError *error);
+
+/**
+ * Free a previously created OpenSSL context.
+ */
+void redisFreeSSLContext(redisSSLContext *redis_ssl_ctx);
+
+/**
+ * Initiate SSL on an existing redisContext.
+ *
+ * This is similar to redisInitiateSSL() but does not require the caller
+ * to directly interact with OpenSSL, and instead uses a redisSSLContext
+ * previously created using redisCreateSSLContext().
+ */
+
+int redisInitiateSSLWithContext(redisContext *c, redisSSLContext *redis_ssl_ctx);
+
+/**
+ * Initiate SSL/TLS negotiation on a provided OpenSSL SSL object.
+ */
+
+int redisInitiateSSL(redisContext *c, struct ssl_st *ssl);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif  /* __HIREDIS_SSL_H */

src/net.c

@@ -0,0 +1,556 @@
+/* Extracted from anet.c to work properly with Hiredis error reporting.
+ *
+ * Copyright (c) 2009-2011, Salvatore Sanfilippo <antirez at gmail dot com>
+ * Copyright (c) 2010-2014, Pieter Noordhuis <pcnoordhuis at gmail dot com>
+ * Copyright (c) 2015, Matt Stancliff <matt at genges dot com>,
+ *                     Jan-Erik Rediger <janerik at fnordig dot com>
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "fmacros.h"
+#include <sys/types.h>
+#include <fcntl.h>
+#include <string.h>
+#include <errno.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <limits.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netinet/tcp.h>
+#include <sys/poll.h>
+#include <arpa/inet.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netdb.h>
+#include <stdio.h>
+
+#include "net.h"
+#include "sds.h"
+
+/* Defined in hiredis.c */
+void __redisSetError(redisContext *c, int type, const char *str);
+
+void redisNetClose(redisContext *c) {
+    if (c && c->fd != REDIS_INVALID_FD) {
+        close(c->fd);
+        c->fd = REDIS_INVALID_FD;
+    }
+}
+
+ssize_t redisNetRead(redisContext *c, char *buf, size_t bufcap) {
+    ssize_t nread = recv(c->fd, buf, bufcap, 0);
+    if (nread == -1) {
+        if ((errno == EWOULDBLOCK && !(c->flags & REDIS_BLOCK)) || (errno == EINTR)) {
+            /* Try again later */
+            return 0;
+        } else if (errno == ETIMEDOUT && (c->flags & REDIS_BLOCK)) {
+            /* especially in windows */
+            __redisSetError(c, REDIS_ERR_TIMEOUT, "recv timeout");
+            return -1;
+        } else {
+            __redisSetError(c, REDIS_ERR_IO, NULL);
+            return -1;
+        }
+    } else if (nread == 0) {
+        __redisSetError(c, REDIS_ERR_EOF, "Server closed the connection");
+        return -1;
+    } else {
+        return nread;
+    }
+}
+
+ssize_t redisNetWrite(redisContext *c) {
+    ssize_t nwritten = send(c->fd, c->obuf, hi_sdslen(c->obuf), 0);
+    if (nwritten < 0) {
+        if ((errno == EWOULDBLOCK && !(c->flags & REDIS_BLOCK)) || (errno == EINTR)) {
+            /* Try again later */
+        } else {
+            __redisSetError(c, REDIS_ERR_IO, NULL);
+            return -1;
+        }
+    }
+    return nwritten;
+}
+
+static void __redisSetErrorFromErrno(redisContext *c, int type, const char *prefix) {
+    int errorno = errno;  /* snprintf() may change errno */
+    char buf[128] = {0};
+    size_t len = 0;
+
+    if (prefix != NULL)
+        len = snprintf(buf, sizeof(buf), "%s: ", prefix);
+    strerror_r(errorno, (char *) (buf + len), sizeof(buf) - len);
+    __redisSetError(c, type, buf);
+}
+
+static int redisSetReuseAddr(redisContext *c) {
+    int on = 1;
+    if (setsockopt(c->fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1) {
+        __redisSetErrorFromErrno(c, REDIS_ERR_IO, NULL);
+        redisNetClose(c);
+        return REDIS_ERR;
+    }
+    return REDIS_OK;
+}
+
+static int redisCreateSocket(redisContext *c, int type) {
+    redisFD s;
+    if ((s = socket(type, SOCK_STREAM, 0)) == REDIS_INVALID_FD) {
+        __redisSetErrorFromErrno(c, REDIS_ERR_IO, NULL);
+        return REDIS_ERR;
+    }
+    c->fd = s;
+    if (type == AF_INET) {
+        if (redisSetReuseAddr(c) == REDIS_ERR) {
+            return REDIS_ERR;
+        }
+    }
+    return REDIS_OK;
+}
+
+static int redisSetBlocking(redisContext *c, int blocking) {
+#ifndef _WIN32
+    int flags;
+
+    /* Set the socket nonblocking.
+     * Note that fcntl(2) for F_GETFL and F_SETFL can't be
+     * interrupted by a signal. */
+    if ((flags = fcntl(c->fd, F_GETFL)) == -1) {
+        __redisSetErrorFromErrno(c, REDIS_ERR_IO, "fcntl(F_GETFL)");
+        redisNetClose(c);
+        return REDIS_ERR;
+    }
+
+    if (blocking)
+        flags &= ~O_NONBLOCK;
+    else
+        flags |= O_NONBLOCK;
+
+    if (fcntl(c->fd, F_SETFL, flags) == -1) {
+        __redisSetErrorFromErrno(c, REDIS_ERR_IO, "fcntl(F_SETFL)");
+        redisNetClose(c);
+        return REDIS_ERR;
+    }
+#else
+    u_long mode = blocking ? 0 : 1;
+    if (ioctl(c->fd, FIONBIO, &mode) == -1) {
+        __redisSetErrorFromErrno(c, REDIS_ERR_IO, "ioctl(FIONBIO)");
+        redisNetClose(c);
+        return REDIS_ERR;
+    }
+#endif /* _WIN32 */
+    return REDIS_OK;
+}
+
+int redisKeepAlive(redisContext *c, int interval) {
+    int val = 1;
+    redisFD fd = c->fd;
+
+    if (setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, &val, sizeof(val)) == -1) {
+        __redisSetError(c, REDIS_ERR_OTHER, strerror(errno));
+        return REDIS_ERR;
+    }
+
+    val = interval;
+
+#if defined(__APPLE__) && defined(__MACH__)
+    if (setsockopt(fd, IPPROTO_TCP, TCP_KEEPALIVE, &val, sizeof(val)) < 0) {
+        __redisSetError(c,REDIS_ERR_OTHER,strerror(errno));
+        return REDIS_ERR;
+    }
+#else
+#if defined(__GLIBC__) && !defined(__FreeBSD_kernel__)
+    if (setsockopt(fd, IPPROTO_TCP, TCP_KEEPIDLE, &val, sizeof(val)) < 0) {
+        __redisSetError(c, REDIS_ERR_OTHER, strerror(errno));
+        return REDIS_ERR;
+    }
+
+    val = interval / 3;
+    if (val == 0) val = 1;
+    if (setsockopt(fd, IPPROTO_TCP, TCP_KEEPINTVL, &val, sizeof(val)) < 0) {
+        __redisSetError(c, REDIS_ERR_OTHER, strerror(errno));
+        return REDIS_ERR;
+    }
+
+    val = 3;
+    if (setsockopt(fd, IPPROTO_TCP, TCP_KEEPCNT, &val, sizeof(val)) < 0) {
+        __redisSetError(c, REDIS_ERR_OTHER, strerror(errno));
+        return REDIS_ERR;
+    }
+#endif
+#endif
+
+    return REDIS_OK;
+}
+
+int redisSetTcpNoDelay(redisContext *c) {
+    int yes = 1;
+    if (setsockopt(c->fd, IPPROTO_TCP, TCP_NODELAY, &yes, sizeof(yes)) == -1) {
+        __redisSetErrorFromErrno(c, REDIS_ERR_IO, "setsockopt(TCP_NODELAY)");
+        redisNetClose(c);
+        return REDIS_ERR;
+    }
+    return REDIS_OK;
+}
+
+#define __MAX_MSEC (((LONG_MAX) - 999) / 1000)
+
+static int redisContextTimeoutMsec(redisContext *c, long *result) {
+    const struct timeval *timeout = c->connect_timeout;
+    long msec = -1;
+
+    /* Only use timeout when not NULL. */
+    if (timeout != NULL) {
+        if (timeout->tv_usec > 1000000 || timeout->tv_sec > __MAX_MSEC) {
+            *result = msec;
+            return REDIS_ERR;
+        }
+
+        msec = (timeout->tv_sec * 1000) + ((timeout->tv_usec + 999) / 1000);
+
+        if (msec < 0 || msec > INT_MAX) {
+            msec = INT_MAX;
+        }
+    }
+
+    *result = msec;
+    return REDIS_OK;
+}
+
+static int redisContextWaitReady(redisContext *c, long msec) {
+    struct pollfd wfd[1];
+
+    wfd[0].fd = c->fd;
+    wfd[0].events = POLLOUT;
+
+    if (errno == EINPROGRESS) {
+        int res;
+
+        if ((res = poll(wfd, 1, msec)) == -1) {
+            __redisSetErrorFromErrno(c, REDIS_ERR_IO, "poll(2)");
+            redisNetClose(c);
+            return REDIS_ERR;
+        } else if (res == 0) {
+            errno = ETIMEDOUT;
+            __redisSetErrorFromErrno(c, REDIS_ERR_IO, NULL);
+            redisNetClose(c);
+            return REDIS_ERR;
+        }
+
+        if (redisCheckConnectDone(c, &res) != REDIS_OK || res == 0) {
+            redisCheckSocketError(c);
+            return REDIS_ERR;
+        }
+
+        return REDIS_OK;
+    }
+
+    __redisSetErrorFromErrno(c, REDIS_ERR_IO, NULL);
+    redisNetClose(c);
+    return REDIS_ERR;
+}
+
+int redisCheckConnectDone(redisContext *c, int *completed) {
+    int rc = connect(c->fd, (const struct sockaddr *) c->saddr, c->addrlen);
+    if (rc == 0) {
+        *completed = 1;
+        return REDIS_OK;
+    }
+    switch (errno) {
+        case EISCONN:
+            *completed = 1;
+            return REDIS_OK;
+        case EALREADY:
+        case EINPROGRESS:
+        case EWOULDBLOCK:
+            *completed = 0;
+            return REDIS_OK;
+        default:
+            return REDIS_ERR;
+    }
+}
+
+int redisCheckSocketError(redisContext *c) {
+    int err = 0, errno_saved = errno;
+    socklen_t errlen = sizeof(err);
+
+    if (getsockopt(c->fd, SOL_SOCKET, SO_ERROR, &err, &errlen) == -1) {
+        __redisSetErrorFromErrno(c, REDIS_ERR_IO, "getsockopt(SO_ERROR)");
+        return REDIS_ERR;
+    }
+
+    if (err == 0) {
+        err = errno_saved;
+    }
+
+    if (err) {
+        errno = err;
+        __redisSetErrorFromErrno(c, REDIS_ERR_IO, NULL);
+        return REDIS_ERR;
+    }
+
+    return REDIS_OK;
+}
+
+int redisContextSetTimeout(redisContext *c, const struct timeval tv) {
+    const void *to_ptr = &tv;
+    size_t to_sz = sizeof(tv);
+
+    if (setsockopt(c->fd, SOL_SOCKET, SO_RCVTIMEO, to_ptr, to_sz) == -1) {
+        __redisSetErrorFromErrno(c, REDIS_ERR_IO, "setsockopt(SO_RCVTIMEO)");
+        return REDIS_ERR;
+    }
+    if (setsockopt(c->fd, SOL_SOCKET, SO_SNDTIMEO, to_ptr, to_sz) == -1) {
+        __redisSetErrorFromErrno(c, REDIS_ERR_IO, "setsockopt(SO_SNDTIMEO)");
+        return REDIS_ERR;
+    }
+    return REDIS_OK;
+}
+
+int redisContextUpdateConnectTimeout(redisContext *c, const struct timeval *timeout) {
+    /* Same timeval struct, short circuit */
+    if (c->connect_timeout == timeout)
+        return REDIS_OK;
+
+    /* Allocate context timeval if we need to */
+    if (c->connect_timeout == NULL) {
+        c->connect_timeout = hi_malloc(sizeof(*c->connect_timeout));
+        if (c->connect_timeout == NULL)
+            return REDIS_ERR;
+    }
+
+    memcpy(c->connect_timeout, timeout, sizeof(*c->connect_timeout));
+    return REDIS_OK;
+}
+
+int redisContextUpdateCommandTimeout(redisContext *c, const struct timeval *timeout) {
+    /* Same timeval struct, short circuit */
+    if (c->command_timeout == timeout)
+        return REDIS_OK;
+
+    /* Allocate context timeval if we need to */
+    if (c->command_timeout == NULL) {
+        c->command_timeout = hi_malloc(sizeof(*c->command_timeout));
+        if (c->command_timeout == NULL)
+            return REDIS_ERR;
+    }
+
+    memcpy(c->command_timeout, timeout, sizeof(*c->command_timeout));
+    return REDIS_OK;
+}
+
+static int _redisContextConnectTcp(redisContext *c, const char *addr, int port,
+                                   const struct timeval *timeout,
+                                   const char *source_addr) {
+    redisFD s;
+    int rv, n;
+    char _port[6];  /* strlen("65535"); */
+    struct addrinfo hints, *servinfo, *bservinfo, *p, *b;
+    int blocking = (c->flags & REDIS_BLOCK);
+    int reuseaddr = (c->flags & REDIS_REUSEADDR);
+    int reuses = 0;
+    long timeout_msec = -1;
+
+    servinfo = NULL;
+    c->connection_type = REDIS_CONN_TCP;
+    c->tcp.port = port;
+
+    /* We need to take possession of the passed parameters
+     * to make them reusable for a reconnect.
+     * We also carefully check we don't free data we already own,
+     * as in the case of the reconnect method.
+     *
+     * This is a bit ugly, but atleast it works and doesn't leak memory.
+     **/
+    if (c->tcp.host != addr) {
+        hi_free(c->tcp.host);
+
+        c->tcp.host = hi_strdup(addr);
+        if (c->tcp.host == NULL)
+            goto oom;
+    }
+
+    if (timeout) {
+        if (redisContextUpdateConnectTimeout(c, timeout) == REDIS_ERR)
+            goto oom;
+    } else {
+        hi_free(c->connect_timeout);
+        c->connect_timeout = NULL;
+    }
+
+    if (redisContextTimeoutMsec(c, &timeout_msec) != REDIS_OK) {
+        __redisSetError(c, REDIS_ERR_IO, "Invalid timeout specified");
+        goto error;
+    }
+
+    if (source_addr == NULL) {
+        hi_free(c->tcp.source_addr);
+        c->tcp.source_addr = NULL;
+    } else if (c->tcp.source_addr != source_addr) {
+        hi_free(c->tcp.source_addr);
+        c->tcp.source_addr = hi_strdup(source_addr);
+    }
+
+    snprintf(_port, 6, "%d", port);
+    memset(&hints, 0, sizeof(hints));
+    hints.ai_family = AF_INET;
+    hints.ai_socktype = SOCK_STREAM;
+
+    /* Try with IPv6 if no IPv4 address was found. We do it in this order since
+     * in a Redis client you can't afford to test if you have IPv6 connectivity
+     * as this would add latency to every connect. Otherwise a more sensible
+     * route could be: Use IPv6 if both addresses are available and there is IPv6
+     * connectivity. */
+    if ((rv = getaddrinfo(c->tcp.host, _port, &hints, &servinfo)) != 0) {
+        hints.ai_family = AF_INET6;
+        if ((rv = getaddrinfo(addr, _port, &hints, &servinfo)) != 0) {
+            __redisSetError(c, REDIS_ERR_OTHER, gai_strerror(rv));
+            return REDIS_ERR;
+        }
+    }
+    for (p = servinfo; p != NULL; p = p->ai_next) {
+        addrretry:
+        if ((s = socket(p->ai_family, p->ai_socktype, p->ai_protocol)) == REDIS_INVALID_FD)
+            continue;
+
+        c->fd = s;
+        if (redisSetBlocking(c, 0) != REDIS_OK)
+            goto error;
+        if (c->tcp.source_addr) {
+            int bound = 0;
+            /* Using getaddrinfo saves us from self-determining IPv4 vs IPv6 */
+            if ((rv = getaddrinfo(c->tcp.source_addr, NULL, &hints, &bservinfo)) != 0) {
+                char buf[128];
+                snprintf(buf, sizeof(buf), "Can't get addr: %s", gai_strerror(rv));
+                __redisSetError(c, REDIS_ERR_OTHER, buf);
+                goto error;
+            }
+
+            if (reuseaddr) {
+                n = 1;
+                if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (char *) &n,
+                               sizeof(n)) < 0) {
+                    freeaddrinfo(bservinfo);
+                    goto error;
+                }
+            }
+
+            for (b = bservinfo; b != NULL; b = b->ai_next) {
+                if (bind(s, b->ai_addr, b->ai_addrlen) != -1) {
+                    bound = 1;
+                    break;
+                }
+            }
+            freeaddrinfo(bservinfo);
+            if (!bound) {
+                char buf[128];
+                snprintf(buf, sizeof(buf), "Can't bind socket: %s", strerror(errno));
+                __redisSetError(c, REDIS_ERR_OTHER, buf);
+                goto error;
+            }
+        }
+
+        /* For repeat connection */
+        hi_free(c->saddr);
+        c->saddr = hi_malloc(p->ai_addrlen);
+        if (c->saddr == NULL)
+            goto oom;
+
+        memcpy(c->saddr, p->ai_addr, p->ai_addrlen);
+        c->addrlen = p->ai_addrlen;
+
+        if (connect(s, p->ai_addr, p->ai_addrlen) == -1) {
+            if (errno == EHOSTUNREACH) {
+                redisNetClose(c);
+                continue;
+            } else if (errno == EINPROGRESS) {
+                if (blocking) {
+                    goto wait_for_ready;
+                }
+                /* This is ok.
+                 * Note that even when it's in blocking mode, we unset blocking
+                 * for `connect()`
+                 */
+            } else if (errno == EADDRNOTAVAIL && reuseaddr) {
+                if (++reuses >= REDIS_CONNECT_RETRIES) {
+                    goto error;
+                } else {
+                    redisNetClose(c);
+                    goto addrretry;
+                }
+            } else {
+                wait_for_ready:
+                if (redisContextWaitReady(c, timeout_msec) != REDIS_OK)
+                    goto error;
+                if (redisSetTcpNoDelay(c) != REDIS_OK)
+                    goto error;
+            }
+        }
+        if (blocking && redisSetBlocking(c, 1) != REDIS_OK)
+            goto error;
+
+        c->flags |= REDIS_CONNECTED;
+        rv = REDIS_OK;
+        goto end;
+    }
+    if (p == NULL) {
+        char buf[128];
+        snprintf(buf, sizeof(buf), "Can't create socket: %s", strerror(errno));
+        __redisSetError(c, REDIS_ERR_OTHER, buf);
+        goto error;
+    }
+
+    oom:
+    __redisSetError(c, REDIS_ERR_OOM, "Out of memory");
+    error:
+    rv = REDIS_ERR;
+    end:
+    if (servinfo) {
+        freeaddrinfo(servinfo);
+    }
+
+    return rv;  // Need to return REDIS_OK if alright
+}
+
+int redisContextConnectTcp(redisContext *c, const char *addr, int port,
+                           const struct timeval *timeout) {
+    return _redisContextConnectTcp(c, addr, port, timeout, NULL);
+}
+
+int redisContextConnectBindTcp(redisContext *c, const char *addr, int port,
+                               const struct timeval *timeout,
+                               const char *source_addr) {
+    return _redisContextConnectTcp(c, addr, port, timeout, source_addr);
+}
+
+int redisContextConnectUnix(redisContext *c, const char *path, const struct timeval *timeout) {
+    return REDIS_ERR;
+}

src/net.h

@@ -0,0 +1,56 @@
+/* Extracted from anet.c to work properly with Hiredis error reporting.
+ *
+ * Copyright (c) 2009-2011, Salvatore Sanfilippo <antirez at gmail dot com>
+ * Copyright (c) 2010-2014, Pieter Noordhuis <pcnoordhuis at gmail dot com>
+ * Copyright (c) 2015, Matt Stancliff <matt at genges dot com>,
+ *                     Jan-Erik Rediger <janerik at fnordig dot com>
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __NET_H
+#define __NET_H
+
+#include "hiredis.h"
+
+void redisNetClose(redisContext *c);
+ssize_t redisNetRead(redisContext *c, char *buf, size_t bufcap);
+ssize_t redisNetWrite(redisContext *c);
+
+int redisCheckSocketError(redisContext *c);
+int redisContextSetTimeout(redisContext *c, const struct timeval tv);
+int redisContextConnectTcp(redisContext *c, const char *addr, int port, const struct timeval *timeout);
+int redisContextConnectBindTcp(redisContext *c, const char *addr, int port,
+                               const struct timeval *timeout,
+                               const char *source_addr);
+int redisContextConnectUnix(redisContext *c, const char *path, const struct timeval *timeout);
+int redisKeepAlive(redisContext *c, int interval);
+int redisCheckConnectDone(redisContext *c, int *completed);
+
+int redisSetTcpNoDelay(redisContext *c);
+
+#endif

src/read.c

@@ -0,0 +1,784 @@
+/*
+ * Copyright (c) 2009-2011, Salvatore Sanfilippo <antirez at gmail dot com>
+ * Copyright (c) 2010-2011, Pieter Noordhuis <pcnoordhuis at gmail dot com>
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "fmacros.h"
+#include <string.h>
+#include <stdlib.h>
+#ifndef _MSC_VER
+#include <unistd.h>
+#include <strings.h>
+#endif
+#include <assert.h>
+#include <errno.h>
+#include <ctype.h>
+#include <limits.h>
+#include <math.h>
+
+#include "alloc.h"
+#include "read.h"
+#include "sds.h"
+
+/* Initial size of our nested reply stack and how much we grow it when needd */
+#define REDIS_READER_STACK_SIZE 9
+
+static void __redisReaderSetError(redisReader *r, int type, const char *str) {
+    size_t len;
+
+    if (r->reply != NULL && r->fn && r->fn->freeObject) {
+        r->fn->freeObject(r->reply);
+        r->reply = NULL;
+    }
+
+    /* Clear input buffer on errors. */
+    hi_sdsfree(r->buf);
+    r->buf = NULL;
+    r->pos = r->len = 0;
+
+    /* Reset task stack. */
+    r->ridx = -1;
+
+    /* Set error. */
+    r->err = type;
+    len = strlen(str);
+    len = len < (sizeof(r->errstr)-1) ? len : (sizeof(r->errstr)-1);
+    memcpy(r->errstr,str,len);
+    r->errstr[len] = '\0';
+}
+
+static size_t chrtos(char *buf, size_t size, char byte) {
+    size_t len = 0;
+
+    switch(byte) {
+    case '\\':
+    case '"':
+        len = snprintf(buf,size,"\"\\%c\"",byte);
+        break;
+    case '\n': len = snprintf(buf,size,"\"\\n\""); break;
+    case '\r': len = snprintf(buf,size,"\"\\r\""); break;
+    case '\t': len = snprintf(buf,size,"\"\\t\""); break;
+    case '\a': len = snprintf(buf,size,"\"\\a\""); break;
+    case '\b': len = snprintf(buf,size,"\"\\b\""); break;
+    default:
+        if (isprint(byte))
+            len = snprintf(buf,size,"\"%c\"",byte);
+        else
+            len = snprintf(buf,size,"\"\\x%02x\"",(unsigned char)byte);
+        break;
+    }
+
+    return len;
+}
+
+static void __redisReaderSetErrorProtocolByte(redisReader *r, char byte) {
+    char cbuf[8], sbuf[128];
+
+    chrtos(cbuf,sizeof(cbuf),byte);
+    snprintf(sbuf,sizeof(sbuf),
+        "Protocol error, got %s as reply type byte", cbuf);
+    __redisReaderSetError(r,REDIS_ERR_PROTOCOL,sbuf);
+}
+
+static void __redisReaderSetErrorOOM(redisReader *r) {
+    __redisReaderSetError(r,REDIS_ERR_OOM,"Out of memory");
+}
+
+static char *readBytes(redisReader *r, unsigned int bytes) {
+    char *p;
+    if (r->len-r->pos >= bytes) {
+        p = r->buf+r->pos;
+        r->pos += bytes;
+        return p;
+    }
+    return NULL;
+}
+
+/* Find pointer to \r\n. */
+static char *seekNewline(char *s, size_t len) {
+    char *ret;
+
+    /* We cannot match with fewer than 2 bytes */
+    if (len < 2)
+        return NULL;
+
+    /* Search up to len - 1 characters */
+    len--;
+
+    /* Look for the \r */
+    while ((ret = memchr(s, '\r', len)) != NULL) {
+        if (ret[1] == '\n') {
+            /* Found. */
+            break;
+        }
+        /* Continue searching. */
+        ret++;
+        len -= ret - s;
+        s = ret;
+    }
+
+    return ret;
+}
+
+/* Convert a string into a long long. Returns REDIS_OK if the string could be
+ * parsed into a (non-overflowing) long long, REDIS_ERR otherwise. The value
+ * will be set to the parsed value when appropriate.
+ *
+ * Note that this function demands that the string strictly represents
+ * a long long: no spaces or other characters before or after the string
+ * representing the number are accepted, nor zeroes at the start if not
+ * for the string "0" representing the zero number.
+ *
+ * Because of its strictness, it is safe to use this function to check if
+ * you can convert a string into a long long, and obtain back the string
+ * from the number without any loss in the string representation. */
+static int string2ll(const char *s, size_t slen, long long *value) {
+    const char *p = s;
+    size_t plen = 0;
+    int negative = 0;
+    unsigned long long v;
+
+    if (plen == slen)
+        return REDIS_ERR;
+
+    /* Special case: first and only digit is 0. */
+    if (slen == 1 && p[0] == '0') {
+        if (value != NULL) *value = 0;
+        return REDIS_OK;
+    }
+
+    if (p[0] == '-') {
+        negative = 1;
+        p++; plen++;
+
+        /* Abort on only a negative sign. */
+        if (plen == slen)
+            return REDIS_ERR;
+    }
+
+    /* First digit should be 1-9, otherwise the string should just be 0. */
+    if (p[0] >= '1' && p[0] <= '9') {
+        v = p[0]-'0';
+        p++; plen++;
+    } else if (p[0] == '0' && slen == 1) {
+        *value = 0;
+        return REDIS_OK;
+    } else {
+        return REDIS_ERR;
+    }
+
+    while (plen < slen && p[0] >= '0' && p[0] <= '9') {
+        if (v > (ULLONG_MAX / 10)) /* Overflow. */
+            return REDIS_ERR;
+        v *= 10;
+
+        if (v > (ULLONG_MAX - (p[0]-'0'))) /* Overflow. */
+            return REDIS_ERR;
+        v += p[0]-'0';
+
+        p++; plen++;
+    }
+
+    /* Return if not all bytes were used. */
+    if (plen < slen)
+        return REDIS_ERR;
+
+    if (negative) {
+        if (v > ((unsigned long long)(-(LLONG_MIN+1))+1)) /* Overflow. */
+            return REDIS_ERR;
+        if (value != NULL) *value = -v;
+    } else {
+        if (v > LLONG_MAX) /* Overflow. */
+            return REDIS_ERR;
+        if (value != NULL) *value = v;
+    }
+    return REDIS_OK;
+}
+
+static char *readLine(redisReader *r, int *_len) {
+    char *p, *s;
+    int len;
+
+    p = r->buf+r->pos;
+    s = seekNewline(p,(r->len-r->pos));
+    if (s != NULL) {
+        len = s-(r->buf+r->pos);
+        r->pos += len+2; /* skip \r\n */
+        if (_len) *_len = len;
+        return p;
+    }
+    return NULL;
+}
+
+static void moveToNextTask(redisReader *r) {
+    redisReadTask *cur, *prv;
+    while (r->ridx >= 0) {
+        /* Return a.s.a.p. when the stack is now empty. */
+        if (r->ridx == 0) {
+            r->ridx--;
+            return;
+        }
+
+        cur = r->task[r->ridx];
+        prv = r->task[r->ridx-1];
+        assert(prv->type == REDIS_REPLY_ARRAY ||
+               prv->type == REDIS_REPLY_MAP ||
+               prv->type == REDIS_REPLY_SET ||
+               prv->type == REDIS_REPLY_PUSH);
+        if (cur->idx == prv->elements-1) {
+            r->ridx--;
+        } else {
+            /* Reset the type because the next item can be anything */
+            assert(cur->idx < prv->elements);
+            cur->type = -1;
+            cur->elements = -1;
+            cur->idx++;
+            return;
+        }
+    }
+}
+
+static int processLineItem(redisReader *r) {
+    redisReadTask *cur = r->task[r->ridx];
+    void *obj;
+    char *p;
+    int len;
+
+    if ((p = readLine(r,&len)) != NULL) {
+        if (cur->type == REDIS_REPLY_INTEGER) {
+            long long v;
+
+            if (string2ll(p, len, &v) == REDIS_ERR) {
+                __redisReaderSetError(r,REDIS_ERR_PROTOCOL,
+                        "Bad integer value");
+                return REDIS_ERR;
+            }
+
+            if (r->fn && r->fn->createInteger) {
+                obj = r->fn->createInteger(cur,v);
+            } else {
+                obj = (void*)REDIS_REPLY_INTEGER;
+            }
+        } else if (cur->type == REDIS_REPLY_DOUBLE) {
+            char buf[326], *eptr;
+            double d;
+
+            if ((size_t)len >= sizeof(buf)) {
+                __redisReaderSetError(r,REDIS_ERR_PROTOCOL,
+                        "Double value is too large");
+                return REDIS_ERR;
+            }
+
+            memcpy(buf,p,len);
+            buf[len] = '\0';
+
+            if (len == 3 && strcasecmp(buf,"inf") == 0) {
+                d = INFINITY; /* Positive infinite. */
+            } else if (len == 4 && strcasecmp(buf,"-inf") == 0) {
+                d = -INFINITY; /* Negative infinite. */
+            } else {
+                d = strtod((char*)buf,&eptr);
+                /* RESP3 only allows "inf", "-inf", and finite values, while
+                 * strtod() allows other variations on infinity, NaN,
+                 * etc. We explicity handle our two allowed infinite cases
+                 * above, so strtod() should only result in finite values. */
+                if (buf[0] == '\0' || eptr != &buf[len] || !isfinite(d)) {
+                    __redisReaderSetError(r,REDIS_ERR_PROTOCOL,
+                            "Bad double value");
+                    return REDIS_ERR;
+                }
+            }
+
+            if (r->fn && r->fn->createDouble) {
+                obj = r->fn->createDouble(cur,d,buf,len);
+            } else {
+                obj = (void*)REDIS_REPLY_DOUBLE;
+            }
+        } else if (cur->type == REDIS_REPLY_NIL) {
+            if (len != 0) {
+                __redisReaderSetError(r,REDIS_ERR_PROTOCOL,
+                        "Bad nil value");
+                return REDIS_ERR;
+            }
+
+            if (r->fn && r->fn->createNil)
+                obj = r->fn->createNil(cur);
+            else
+                obj = (void*)REDIS_REPLY_NIL;
+        } else if (cur->type == REDIS_REPLY_BOOL) {
+            int bval;
+
+            if (len != 1 || !strchr("tTfF", p[0])) {
+                __redisReaderSetError(r,REDIS_ERR_PROTOCOL,
+                        "Bad bool value");
+                return REDIS_ERR;
+            }
+
+            bval = p[0] == 't' || p[0] == 'T';
+            if (r->fn && r->fn->createBool)
+                obj = r->fn->createBool(cur,bval);
+            else
+                obj = (void*)REDIS_REPLY_BOOL;
+        } else if (cur->type == REDIS_REPLY_BIGNUM) {
+            /* Ensure all characters are decimal digits (with possible leading
+             * minus sign). */
+            for (int i = 0; i < len; i++) {
+                /* XXX Consider: Allow leading '+'? Error on leading '0's? */
+                if (i == 0 && p[0] == '-') continue;
+                if (p[i] < '0' || p[i] > '9') {
+                    __redisReaderSetError(r,REDIS_ERR_PROTOCOL,
+                            "Bad bignum value");
+                    return REDIS_ERR;
+                }
+            }
+            if (r->fn && r->fn->createString)
+                obj = r->fn->createString(cur,p,len);
+            else
+                obj = (void*)REDIS_REPLY_BIGNUM;
+        } else {
+            /* Type will be error or status. */
+            for (int i = 0; i < len; i++) {
+                if (p[i] == '\r' || p[i] == '\n') {
+                    __redisReaderSetError(r,REDIS_ERR_PROTOCOL,
+                            "Bad simple string value");
+                    return REDIS_ERR;
+                }
+            }
+            if (r->fn && r->fn->createString)
+                obj = r->fn->createString(cur,p,len);
+            else
+                obj = (void*)(size_t)(cur->type);
+        }
+
+        if (obj == NULL) {
+            __redisReaderSetErrorOOM(r);
+            return REDIS_ERR;
+        }
+
+        /* Set reply if this is the root object. */
+        if (r->ridx == 0) r->reply = obj;
+        moveToNextTask(r);
+        return REDIS_OK;
+    }
+
+    return REDIS_ERR;
+}
+
+static int processBulkItem(redisReader *r) {
+    redisReadTask *cur = r->task[r->ridx];
+    void *obj = NULL;
+    char *p, *s;
+    long long len;
+    unsigned long bytelen;
+    int success = 0;
+
+    p = r->buf+r->pos;
+    s = seekNewline(p,r->len-r->pos);
+    if (s != NULL) {
+        p = r->buf+r->pos;
+        bytelen = s-(r->buf+r->pos)+2; /* include \r\n */
+
+        if (string2ll(p, bytelen - 2, &len) == REDIS_ERR) {
+            __redisReaderSetError(r,REDIS_ERR_PROTOCOL,
+                    "Bad bulk string length");
+            return REDIS_ERR;
+        }
+
+        if (len < -1 || (LLONG_MAX > SIZE_MAX && len > (long long)SIZE_MAX)) {
+            __redisReaderSetError(r,REDIS_ERR_PROTOCOL,
+                    "Bulk string length out of range");
+            return REDIS_ERR;
+        }
+
+        if (len == -1) {
+            /* The nil object can always be created. */
+            if (r->fn && r->fn->createNil)
+                obj = r->fn->createNil(cur);
+            else
+                obj = (void*)REDIS_REPLY_NIL;
+            success = 1;
+        } else {
+            /* Only continue when the buffer contains the entire bulk item. */
+            bytelen += len+2; /* include \r\n */
+            if (r->pos+bytelen <= r->len) {
+                if ((cur->type == REDIS_REPLY_VERB && len < 4) ||
+                    (cur->type == REDIS_REPLY_VERB && s[5] != ':'))
+                {
+                    __redisReaderSetError(r,REDIS_ERR_PROTOCOL,
+                            "Verbatim string 4 bytes of content type are "
+                            "missing or incorrectly encoded.");
+                    return REDIS_ERR;
+                }
+                if (r->fn && r->fn->createString)
+                    obj = r->fn->createString(cur,s+2,len);
+                else
+                    obj = (void*)(long)cur->type;
+                success = 1;
+            }
+        }
+
+        /* Proceed when obj was created. */
+        if (success) {
+            if (obj == NULL) {
+                __redisReaderSetErrorOOM(r);
+                return REDIS_ERR;
+            }
+
+            r->pos += bytelen;
+
+            /* Set reply if this is the root object. */
+            if (r->ridx == 0) r->reply = obj;
+            moveToNextTask(r);
+            return REDIS_OK;
+        }
+    }
+
+    return REDIS_ERR;
+}
+
+static int redisReaderGrow(redisReader *r) {
+    redisReadTask **aux;
+    int newlen;
+
+    /* Grow our stack size */
+    newlen = r->tasks + REDIS_READER_STACK_SIZE;
+    aux = hi_realloc(r->task, sizeof(*r->task) * newlen);
+    if (aux == NULL)
+        goto oom;
+
+    r->task = aux;
+
+    /* Allocate new tasks */
+    for (; r->tasks < newlen; r->tasks++) {
+        r->task[r->tasks] = hi_calloc(1, sizeof(**r->task));
+        if (r->task[r->tasks] == NULL)
+            goto oom;
+    }
+
+    return REDIS_OK;
+oom:
+    __redisReaderSetErrorOOM(r);
+    return REDIS_ERR;
+}
+
+/* Process the array, map and set types. */
+static int processAggregateItem(redisReader *r) {
+    redisReadTask *cur = r->task[r->ridx];
+    void *obj;
+    char *p;
+    long long elements;
+    int root = 0, len;
+
+    if (r->ridx == r->tasks - 1) {
+        if (redisReaderGrow(r) == REDIS_ERR)
+            return REDIS_ERR;
+    }
+
+    if ((p = readLine(r,&len)) != NULL) {
+        if (string2ll(p, len, &elements) == REDIS_ERR) {
+            __redisReaderSetError(r,REDIS_ERR_PROTOCOL,
+                    "Bad multi-bulk length");
+            return REDIS_ERR;
+        }
+
+        root = (r->ridx == 0);
+
+        if (elements < -1 || (LLONG_MAX > SIZE_MAX && elements > SIZE_MAX) ||
+            (r->maxelements > 0 && elements > r->maxelements))
+        {
+            __redisReaderSetError(r,REDIS_ERR_PROTOCOL,
+                    "Multi-bulk length out of range");
+            return REDIS_ERR;
+        }
+
+        if (elements == -1) {
+            if (r->fn && r->fn->createNil)
+                obj = r->fn->createNil(cur);
+            else
+                obj = (void*)REDIS_REPLY_NIL;
+
+            if (obj == NULL) {
+                __redisReaderSetErrorOOM(r);
+                return REDIS_ERR;
+            }
+
+            moveToNextTask(r);
+        } else {
+            if (cur->type == REDIS_REPLY_MAP) elements *= 2;
+
+            if (r->fn && r->fn->createArray)
+                obj = r->fn->createArray(cur,elements);
+            else
+                obj = (void*)(long)cur->type;
+
+            if (obj == NULL) {
+                __redisReaderSetErrorOOM(r);
+                return REDIS_ERR;
+            }
+
+            /* Modify task stack when there are more than 0 elements. */
+            if (elements > 0) {
+                cur->elements = elements;
+                cur->obj = obj;
+                r->ridx++;
+                r->task[r->ridx]->type = -1;
+                r->task[r->ridx]->elements = -1;
+                r->task[r->ridx]->idx = 0;
+                r->task[r->ridx]->obj = NULL;
+                r->task[r->ridx]->parent = cur;
+                r->task[r->ridx]->privdata = r->privdata;
+            } else {
+                moveToNextTask(r);
+            }
+        }
+
+        /* Set reply if this is the root object. */
+        if (root) r->reply = obj;
+        return REDIS_OK;
+    }
+
+    return REDIS_ERR;
+}
+
+static int processItem(redisReader *r) {
+    redisReadTask *cur = r->task[r->ridx];
+    char *p;
+
+    /* check if we need to read type */
+    if (cur->type < 0) {
+        if ((p = readBytes(r,1)) != NULL) {
+            switch (p[0]) {
+            case '-':
+                cur->type = REDIS_REPLY_ERROR;
+                break;
+            case '+':
+                cur->type = REDIS_REPLY_STATUS;
+                break;
+            case ':':
+                cur->type = REDIS_REPLY_INTEGER;
+                break;
+            case ',':
+                cur->type = REDIS_REPLY_DOUBLE;
+                break;
+            case '_':
+                cur->type = REDIS_REPLY_NIL;
+                break;
+            case '$':
+                cur->type = REDIS_REPLY_STRING;
+                break;
+            case '*':
+                cur->type = REDIS_REPLY_ARRAY;
+                break;
+            case '%':
+                cur->type = REDIS_REPLY_MAP;
+                break;
+            case '~':
+                cur->type = REDIS_REPLY_SET;
+                break;
+            case '#':
+                cur->type = REDIS_REPLY_BOOL;
+                break;
+            case '=':
+                cur->type = REDIS_REPLY_VERB;
+                break;
+            case '>':
+                cur->type = REDIS_REPLY_PUSH;
+                break;
+            case '(':
+                cur->type = REDIS_REPLY_BIGNUM;
+                break;
+            default:
+                __redisReaderSetErrorProtocolByte(r,*p);
+                return REDIS_ERR;
+            }
+        } else {
+            /* could not consume 1 byte */
+            return REDIS_ERR;
+        }
+    }
+
+    /* process typed item */
+    switch(cur->type) {
+    case REDIS_REPLY_ERROR:
+    case REDIS_REPLY_STATUS:
+    case REDIS_REPLY_INTEGER:
+    case REDIS_REPLY_DOUBLE:
+    case REDIS_REPLY_NIL:
+    case REDIS_REPLY_BOOL:
+    case REDIS_REPLY_BIGNUM:
+        return processLineItem(r);
+    case REDIS_REPLY_STRING:
+    case REDIS_REPLY_VERB:
+        return processBulkItem(r);
+    case REDIS_REPLY_ARRAY:
+    case REDIS_REPLY_MAP:
+    case REDIS_REPLY_SET:
+    case REDIS_REPLY_PUSH:
+        return processAggregateItem(r);
+    default:
+        assert(NULL);
+        return REDIS_ERR; /* Avoid warning. */
+    }
+}
+
+redisReader *redisReaderCreateWithFunctions(redisReplyObjectFunctions *fn) {
+    redisReader *r;
+
+    r = hi_calloc(1,sizeof(redisReader));
+    if (r == NULL)
+        return NULL;
+
+    r->buf = hi_sdsempty();
+    if (r->buf == NULL)
+        goto oom;
+
+    r->task = hi_calloc(REDIS_READER_STACK_SIZE, sizeof(*r->task));
+    if (r->task == NULL)
+        goto oom;
+
+    for (; r->tasks < REDIS_READER_STACK_SIZE; r->tasks++) {
+        r->task[r->tasks] = hi_calloc(1, sizeof(**r->task));
+        if (r->task[r->tasks] == NULL)
+            goto oom;
+    }
+
+    r->fn = fn;
+    r->maxbuf = REDIS_READER_MAX_BUF;
+    r->maxelements = REDIS_READER_MAX_ARRAY_ELEMENTS;
+    r->ridx = -1;
+
+    return r;
+oom:
+    redisReaderFree(r);
+    return NULL;
+}
+
+void redisReaderFree(redisReader *r) {
+    if (r == NULL)
+        return;
+
+    if (r->reply != NULL && r->fn && r->fn->freeObject)
+        r->fn->freeObject(r->reply);
+
+    if (r->task) {
+        /* We know r->task[i] is allocated if i < r->tasks */
+        for (int i = 0; i < r->tasks; i++) {
+            hi_free(r->task[i]);
+        }
+
+        hi_free(r->task);
+    }
+
+    hi_sdsfree(r->buf);
+    hi_free(r);
+}
+
+int redisReaderFeed(redisReader *r, const char *buf, size_t len) {
+    hisds newbuf;
+
+    /* Return early when this reader is in an erroneous state. */
+    if (r->err)
+        return REDIS_ERR;
+
+    /* Copy the provided buffer. */
+    if (buf != NULL && len >= 1) {
+        /* Destroy internal buffer when it is empty and is quite large. */
+        if (r->len == 0 && r->maxbuf != 0 && hi_sdsavail(r->buf) > r->maxbuf) {
+            hi_sdsfree(r->buf);
+            r->buf = hi_sdsempty();
+            if (r->buf == 0) goto oom;
+
+            r->pos = 0;
+        }
+
+        newbuf = hi_sdscatlen(r->buf,buf,len);
+        if (newbuf == NULL) goto oom;
+
+        r->buf = newbuf;
+        r->len = hi_sdslen(r->buf);
+    }
+
+    return REDIS_OK;
+oom:
+    __redisReaderSetErrorOOM(r);
+    return REDIS_ERR;
+}
+
+int redisReaderGetReply(redisReader *r, void **reply) {
+    /* Default target pointer to NULL. */
+    if (reply != NULL)
+        *reply = NULL;
+
+    /* Return early when this reader is in an erroneous state. */
+    if (r->err)
+        return REDIS_ERR;
+
+    /* When the buffer is empty, there will never be a reply. */
+    if (r->len == 0)
+        return REDIS_OK;
+
+    /* Set first item to process when the stack is empty. */
+    if (r->ridx == -1) {
+        r->task[0]->type = -1;
+        r->task[0]->elements = -1;
+        r->task[0]->idx = -1;
+        r->task[0]->obj = NULL;
+        r->task[0]->parent = NULL;
+        r->task[0]->privdata = r->privdata;
+        r->ridx = 0;
+    }
+
+    /* Process items in reply. */
+    while (r->ridx >= 0)
+        if (processItem(r) != REDIS_OK)
+            break;
+
+    /* Return ASAP when an error occurred. */
+    if (r->err)
+        return REDIS_ERR;
+
+    /* Discard part of the buffer when we've consumed at least 1k, to avoid
+     * doing unnecessary calls to memmove() in sds.c. */
+    if (r->pos >= 1024) {
+        if (hi_sdsrange(r->buf,r->pos,-1) < 0) return REDIS_ERR;
+        r->pos = 0;
+        r->len = hi_sdslen(r->buf);
+    }
+
+    /* Emit a reply when there is one. */
+    if (r->ridx == -1) {
+        if (reply != NULL) {
+            *reply = r->reply;
+        } else if (r->reply != NULL && r->fn && r->fn->freeObject) {
+            r->fn->freeObject(r->reply);
+        }
+        r->reply = NULL;
+    }
+    return REDIS_OK;
+}

src/read.h

@@ -0,0 +1,129 @@
+/*
+ * Copyright (c) 2009-2011, Salvatore Sanfilippo <antirez at gmail dot com>
+ * Copyright (c) 2010-2011, Pieter Noordhuis <pcnoordhuis at gmail dot com>
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+
+#ifndef __HIREDIS_READ_H
+#define __HIREDIS_READ_H
+#include <stdio.h> /* for size_t */
+
+#define REDIS_ERR -1
+#define REDIS_OK 0
+
+/* When an error occurs, the err flag in a context is set to hold the type of
+ * error that occurred. REDIS_ERR_IO means there was an I/O error and you
+ * should use the "errno" variable to find out what is wrong.
+ * For other values, the "errstr" field will hold a description. */
+#define REDIS_ERR_IO 1 /* Error in read or write */
+#define REDIS_ERR_EOF 3 /* End of file */
+#define REDIS_ERR_PROTOCOL 4 /* Protocol error */
+#define REDIS_ERR_OOM 5 /* Out of memory */
+#define REDIS_ERR_TIMEOUT 6 /* Timed out */
+#define REDIS_ERR_OTHER 2 /* Everything else... */
+
+#define REDIS_REPLY_STRING 1
+#define REDIS_REPLY_ARRAY 2
+#define REDIS_REPLY_INTEGER 3
+#define REDIS_REPLY_NIL 4
+#define REDIS_REPLY_STATUS 5
+#define REDIS_REPLY_ERROR 6
+#define REDIS_REPLY_DOUBLE 7
+#define REDIS_REPLY_BOOL 8
+#define REDIS_REPLY_MAP 9
+#define REDIS_REPLY_SET 10
+#define REDIS_REPLY_ATTR 11
+#define REDIS_REPLY_PUSH 12
+#define REDIS_REPLY_BIGNUM 13
+#define REDIS_REPLY_VERB 14
+
+/* Default max unused reader buffer. */
+#define REDIS_READER_MAX_BUF (1024*16)
+
+/* Default multi-bulk element limit */
+#define REDIS_READER_MAX_ARRAY_ELEMENTS ((1LL<<32) - 1)
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct redisReadTask {
+    int type;
+    long long elements; /* number of elements in multibulk container */
+    int idx; /* index in parent (array) object */
+    void *obj; /* holds user-generated value for a read task */
+    struct redisReadTask *parent; /* parent task */
+    void *privdata; /* user-settable arbitrary field */
+} redisReadTask;
+
+typedef struct redisReplyObjectFunctions {
+    void *(*createString)(const redisReadTask*, char*, size_t);
+    void *(*createArray)(const redisReadTask*, size_t);
+    void *(*createInteger)(const redisReadTask*, long long);
+    void *(*createDouble)(const redisReadTask*, double, char*, size_t);
+    void *(*createNil)(const redisReadTask*);
+    void *(*createBool)(const redisReadTask*, int);
+    void (*freeObject)(void*);
+} redisReplyObjectFunctions;
+
+typedef struct redisReader {
+    int err; /* Error flags, 0 when there is no error */
+    char errstr[128]; /* String representation of error when applicable */
+
+    char *buf; /* Read buffer */
+    size_t pos; /* Buffer cursor */
+    size_t len; /* Buffer length */
+    size_t maxbuf; /* Max length of unused buffer */
+    long long maxelements; /* Max multi-bulk elements */
+
+    redisReadTask **task;
+    int tasks;
+
+    int ridx; /* Index of current read task */
+    void *reply; /* Temporary reply pointer */
+
+    redisReplyObjectFunctions *fn;
+    void *privdata;
+} redisReader;
+
+/* Public API for the protocol parser. */
+redisReader *redisReaderCreateWithFunctions(redisReplyObjectFunctions *fn);
+void redisReaderFree(redisReader *r);
+int redisReaderFeed(redisReader *r, const char *buf, size_t len);
+int redisReaderGetReply(redisReader *r, void **reply);
+
+#define redisReaderSetPrivdata(_r, _p) (int)(((redisReader*)(_r))->privdata = (_p))
+#define redisReaderGetObject(_r) (((redisReader*)(_r))->reply)
+#define redisReaderGetError(_r) (((redisReader*)(_r))->errstr)
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

src/redis-migrate.c

@@ -1,5 +1,72 @@
 
+#include <sys/time.h>
+#include <unistd.h>
 #include "redis-migrate.h"
+#include "hiredis.h"
+#include "async.h"
+#include "ae.h"
+
+static redisAsyncContext *context;
+char *bind_source_addr;
+static aeEventLoop *loop;
+
+int sync_state;
+
+RedisModuleCtx *moduleCtx;
+
+/* Return the UNIX time in microseconds */
+long long ustime(void) {
+    struct timeval tv;
+    long long ust;
+
+    gettimeofday(&tv, NULL);
+    ust = ((long long) tv.tv_sec) * 1000000;
+    ust += tv.tv_usec;
+    return ust;
+}
+
+/* Return the UNIX time in milliseconds */
+mstime_t mstime(void) {
+    return ustime() / 1000;
+}
+
+void syncWithMaster() {
+
+}
+
+void connectCallback(const redisAsyncContext *c, int status) {
+
+}
+
+void disconnectCallback(const redisAsyncContext *c, int status) {
+
+}
+
+int connectWithSourceRedis(RedisModuleCtx *ctx, robj *host, robj *p) {
+    int port = atoi(p->ptr);
+    context = redisAsyncConnect(host->ptr, port);
+    if (context->err) {
+        RedisModule_Log(ctx, REDISMODULE_LOGLEVEL_WARNING, "Could not connect to Redis at ip:%s,port:%s",
+                        (char *) host->ptr,
+                        (char *) p->ptr);
+        goto err;
+    }
+    loop = aeCreateEventLoop(64);
+    redisAeAttach(loop, context);
+    redisAsyncSetConnectCallback(context, connectCallback);
+    redisAsyncSetDisconnectCallback(context, disconnectCallback);
+    // send commands
+    return C_OK;
+    err:
+    redisAsyncFree((redisAsyncContext *) context);
+    context = NULL;
+
+    if (loop != NULL) {
+        aeStop(loop);
+        loop = NULL;
+    }
+    return C_ERR;
+}
 
 /**
  * migrate data to current instance.
@@ -19,7 +86,12 @@ int rm_migrateCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc) {
     robj *end_slot = (robj *) argv[4];
     RedisModule_Log(ctx, REDISMODULE_LOGLEVEL_NOTICE, "host:%s, port:%s, begin:%s, end:%s", (char *) host->ptr,
                     (char *) port->ptr, (char *) begin_slot->ptr, (char *) end_slot->ptr);
-
+    if (context != NULL) {
+        return RedisModule_ReplyWithError(ctx, "-ERR is migrating, please waiting");
+    }
+    if (connectWithSourceRedis(ctx, host, port) == C_ERR) {
+        return RedisModule_ReplyWithError(ctx, "-ERR Can't connect source");
+    }
     return RedisModule_ReplyWithSimpleString(ctx, "OK");
 }
 
@@ -40,5 +112,6 @@ int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
         RedisModule_Log(ctx, REDISMODULE_LOGLEVEL_WARNING, "init rm.migrate failed");
         return REDISMODULE_ERR;
     }
+    moduleCtx = ctx;
     return REDISMODULE_OK;
 }

src/redis-migrate.h

@@ -7,6 +7,8 @@
 #define MODULE_NAME "redis-migrate"
 #define REDIS_MIGRATE_VERSION 1
 #define LRU_BITS 24
+#define C_ERR -1
+#define C_OK 1
 
 typedef struct redisObject {
     unsigned type: 4;
@@ -18,7 +20,30 @@ typedef struct redisObject {
     void *ptr;
 } robj;
 
+typedef enum {
+    REPL_STATE_NONE = 0,            /* No active replication */
+    REPL_STATE_CONNECT,             /* Must connect to master */
+    REPL_STATE_CONNECTING,          /* Connecting to master */
+    /* --- Handshake states, must be ordered --- */
+    REPL_STATE_RECEIVE_PING_REPLY,  /* Wait for PING reply */
+    REPL_STATE_SEND_HANDSHAKE,      /* Send handshake sequence to master */
+    REPL_STATE_RECEIVE_AUTH_REPLY,  /* Wait for AUTH reply */
+    REPL_STATE_RECEIVE_PORT_REPLY,  /* Wait for REPLCONF reply */
+    REPL_STATE_RECEIVE_IP_REPLY,    /* Wait for REPLCONF reply */
+    REPL_STATE_RECEIVE_CAPA_REPLY,  /* Wait for REPLCONF reply */
+    REPL_STATE_SEND_PSYNC,          /* Send PSYNC */
+    REPL_STATE_RECEIVE_PSYNC_REPLY, /* Wait for PSYNC reply */
+    /* --- End of handshake states --- */
+    REPL_STATE_TRANSFER,        /* Receiving .rdb from master */
+    REPL_STATE_CONNECTED,       /* Connected to master */
+} repl_state;
+
+mstime_t mstime(void);
+
+long long ustime(void);
+
 int rm_migrateCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc);
+
 int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc);
 
 #endif //REDIS_MIGRATE_REDIS_MIGRATE_H

src/sds.h

@@ -0,0 +1,278 @@
+/* SDSLib 2.0 -- A C dynamic strings library
+ *
+ * Copyright (c) 2006-2015, Salvatore Sanfilippo <antirez at gmail dot com>
+ * Copyright (c) 2015, Oran Agra
+ * Copyright (c) 2015, Redis Labs, Inc
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef HIREDIS_SDS_H
+#define HIREDIS_SDS_H
+
+#define HI_SDS_MAX_PREALLOC (1024*1024)
+#ifdef _MSC_VER
+#define __attribute__(x)
+typedef long long ssize_t;
+#define SSIZE_MAX (LLONG_MAX >> 1)
+#endif
+
+#include <sys/types.h>
+#include <stdarg.h>
+#include <stdint.h>
+
+typedef char *hisds;
+
+/* Note: sdshdr5 is never used, we just access the flags byte directly.
+ * However is here to document the layout of type 5 SDS strings. */
+struct __attribute__ ((__packed__)) hisdshdr5 {
+    unsigned char flags; /* 3 lsb of type, and 5 msb of string length */
+    char buf[];
+};
+struct __attribute__ ((__packed__)) hisdshdr8 {
+    uint8_t len; /* used */
+    uint8_t alloc; /* excluding the header and null terminator */
+    unsigned char flags; /* 3 lsb of type, 5 unused bits */
+    char buf[];
+};
+struct __attribute__ ((__packed__)) hisdshdr16 {
+    uint16_t len; /* used */
+    uint16_t alloc; /* excluding the header and null terminator */
+    unsigned char flags; /* 3 lsb of type, 5 unused bits */
+    char buf[];
+};
+struct __attribute__ ((__packed__)) hisdshdr32 {
+    uint32_t len; /* used */
+    uint32_t alloc; /* excluding the header and null terminator */
+    unsigned char flags; /* 3 lsb of type, 5 unused bits */
+    char buf[];
+};
+struct __attribute__ ((__packed__)) hisdshdr64 {
+    uint64_t len; /* used */
+    uint64_t alloc; /* excluding the header and null terminator */
+    unsigned char flags; /* 3 lsb of type, 5 unused bits */
+    char buf[];
+};
+
+#define HI_SDS_TYPE_5  0
+#define HI_SDS_TYPE_8  1
+#define HI_SDS_TYPE_16 2
+#define HI_SDS_TYPE_32 3
+#define HI_SDS_TYPE_64 4
+#define HI_SDS_TYPE_MASK 7
+#define HI_SDS_TYPE_BITS 3
+#define HI_SDS_HDR_VAR(T,s) struct hisdshdr##T *sh = (struct hisdshdr##T *)((s)-(sizeof(struct hisdshdr##T)));
+#define HI_SDS_HDR(T,s) ((struct hisdshdr##T *)((s)-(sizeof(struct hisdshdr##T))))
+#define HI_SDS_TYPE_5_LEN(f) ((f)>>HI_SDS_TYPE_BITS)
+
+static inline size_t hi_sdslen(const hisds s) {
+    unsigned char flags = s[-1];
+    switch(flags & HI_SDS_TYPE_MASK) {
+        case HI_SDS_TYPE_5:
+            return HI_SDS_TYPE_5_LEN(flags);
+        case HI_SDS_TYPE_8:
+            return HI_SDS_HDR(8,s)->len;
+        case HI_SDS_TYPE_16:
+            return HI_SDS_HDR(16,s)->len;
+        case HI_SDS_TYPE_32:
+            return HI_SDS_HDR(32,s)->len;
+        case HI_SDS_TYPE_64:
+            return HI_SDS_HDR(64,s)->len;
+    }
+    return 0;
+}
+
+static inline size_t hi_sdsavail(const hisds s) {
+    unsigned char flags = s[-1];
+    switch(flags&HI_SDS_TYPE_MASK) {
+        case HI_SDS_TYPE_5: {
+            return 0;
+        }
+        case HI_SDS_TYPE_8: {
+            HI_SDS_HDR_VAR(8,s);
+            return sh->alloc - sh->len;
+        }
+        case HI_SDS_TYPE_16: {
+            HI_SDS_HDR_VAR(16,s);
+            return sh->alloc - sh->len;
+        }
+        case HI_SDS_TYPE_32: {
+            HI_SDS_HDR_VAR(32,s);
+            return sh->alloc - sh->len;
+        }
+        case HI_SDS_TYPE_64: {
+            HI_SDS_HDR_VAR(64,s);
+            return sh->alloc - sh->len;
+        }
+    }
+    return 0;
+}
+
+static inline void hi_sdssetlen(hisds s, size_t newlen) {
+    unsigned char flags = s[-1];
+    switch(flags&HI_SDS_TYPE_MASK) {
+        case HI_SDS_TYPE_5:
+            {
+                unsigned char *fp = ((unsigned char*)s)-1;
+                *fp = (unsigned char)(HI_SDS_TYPE_5 | (newlen << HI_SDS_TYPE_BITS));
+            }
+            break;
+        case HI_SDS_TYPE_8:
+            HI_SDS_HDR(8,s)->len = (uint8_t)newlen;
+            break;
+        case HI_SDS_TYPE_16:
+            HI_SDS_HDR(16,s)->len = (uint16_t)newlen;
+            break;
+        case HI_SDS_TYPE_32:
+            HI_SDS_HDR(32,s)->len = (uint32_t)newlen;
+            break;
+        case HI_SDS_TYPE_64:
+            HI_SDS_HDR(64,s)->len = (uint64_t)newlen;
+            break;
+    }
+}
+
+static inline void hi_sdsinclen(hisds s, size_t inc) {
+    unsigned char flags = s[-1];
+    switch(flags&HI_SDS_TYPE_MASK) {
+        case HI_SDS_TYPE_5:
+            {
+                unsigned char *fp = ((unsigned char*)s)-1;
+                unsigned char newlen = HI_SDS_TYPE_5_LEN(flags)+(unsigned char)inc;
+                *fp = HI_SDS_TYPE_5 | (newlen << HI_SDS_TYPE_BITS);
+            }
+            break;
+        case HI_SDS_TYPE_8:
+            HI_SDS_HDR(8,s)->len += (uint8_t)inc;
+            break;
+        case HI_SDS_TYPE_16:
+            HI_SDS_HDR(16,s)->len += (uint16_t)inc;
+            break;
+        case HI_SDS_TYPE_32:
+            HI_SDS_HDR(32,s)->len += (uint32_t)inc;
+            break;
+        case HI_SDS_TYPE_64:
+            HI_SDS_HDR(64,s)->len += (uint64_t)inc;
+            break;
+    }
+}
+
+/* hi_sdsalloc() = hi_sdsavail() + hi_sdslen() */
+static inline size_t hi_sdsalloc(const hisds s) {
+    unsigned char flags = s[-1];
+    switch(flags & HI_SDS_TYPE_MASK) {
+        case HI_SDS_TYPE_5:
+            return HI_SDS_TYPE_5_LEN(flags);
+        case HI_SDS_TYPE_8:
+            return HI_SDS_HDR(8,s)->alloc;
+        case HI_SDS_TYPE_16:
+            return HI_SDS_HDR(16,s)->alloc;
+        case HI_SDS_TYPE_32:
+            return HI_SDS_HDR(32,s)->alloc;
+        case HI_SDS_TYPE_64:
+            return HI_SDS_HDR(64,s)->alloc;
+    }
+    return 0;
+}
+
+static inline void hi_sdssetalloc(hisds s, size_t newlen) {
+    unsigned char flags = s[-1];
+    switch(flags&HI_SDS_TYPE_MASK) {
+        case HI_SDS_TYPE_5:
+            /* Nothing to do, this type has no total allocation info. */
+            break;
+        case HI_SDS_TYPE_8:
+            HI_SDS_HDR(8,s)->alloc = (uint8_t)newlen;
+            break;
+        case HI_SDS_TYPE_16:
+            HI_SDS_HDR(16,s)->alloc = (uint16_t)newlen;
+            break;
+        case HI_SDS_TYPE_32:
+            HI_SDS_HDR(32,s)->alloc = (uint32_t)newlen;
+            break;
+        case HI_SDS_TYPE_64:
+            HI_SDS_HDR(64,s)->alloc = (uint64_t)newlen;
+            break;
+    }
+}
+
+hisds hi_sdsnewlen(const void *init, size_t initlen);
+hisds hi_sdsnew(const char *init);
+hisds hi_sdsempty(void);
+hisds hi_sdsdup(const hisds s);
+void  hi_sdsfree(hisds s);
+hisds hi_sdsgrowzero(hisds s, size_t len);
+hisds hi_sdscatlen(hisds s, const void *t, size_t len);
+hisds hi_sdscat(hisds s, const char *t);
+hisds hi_sdscatsds(hisds s, const hisds t);
+hisds hi_sdscpylen(hisds s, const char *t, size_t len);
+hisds hi_sdscpy(hisds s, const char *t);
+
+hisds hi_sdscatvprintf(hisds s, const char *fmt, va_list ap);
+#ifdef __GNUC__
+hisds hi_sdscatprintf(hisds s, const char *fmt, ...)
+    __attribute__((format(printf, 2, 3)));
+#else
+hisds hi_sdscatprintf(hisds s, const char *fmt, ...);
+#endif
+
+hisds hi_sdscatfmt(hisds s, char const *fmt, ...);
+hisds hi_sdstrim(hisds s, const char *cset);
+int hi_sdsrange(hisds s, ssize_t start, ssize_t end);
+void hi_sdsupdatelen(hisds s);
+void hi_sdsclear(hisds s);
+int hi_sdscmp(const hisds s1, const hisds s2);
+hisds *hi_sdssplitlen(const char *s, int len, const char *sep, int seplen, int *count);
+void hi_sdsfreesplitres(hisds *tokens, int count);
+void hi_sdstolower(hisds s);
+void hi_sdstoupper(hisds s);
+hisds hi_sdsfromlonglong(long long value);
+hisds hi_sdscatrepr(hisds s, const char *p, size_t len);
+hisds *hi_sdssplitargs(const char *line, int *argc);
+hisds hi_sdsmapchars(hisds s, const char *from, const char *to, size_t setlen);
+hisds hi_sdsjoin(char **argv, int argc, char *sep);
+hisds hi_sdsjoinsds(hisds *argv, int argc, const char *sep, size_t seplen);
+
+/* Low level functions exposed to the user API */
+hisds hi_sdsMakeRoomFor(hisds s, size_t addlen);
+void hi_sdsIncrLen(hisds s, int incr);
+hisds hi_sdsRemoveFreeSpace(hisds s);
+size_t hi_sdsAllocSize(hisds s);
+void *hi_sdsAllocPtr(hisds s);
+
+/* Export the allocator used by SDS to the program using SDS.
+ * Sometimes the program SDS is linked to, may use a different set of
+ * allocators, but may want to allocate or free things that SDS will
+ * respectively free or allocate. */
+void *hi_sds_malloc(size_t size);
+void *hi_sds_realloc(void *ptr, size_t size);
+void hi_sds_free(void *ptr);
+
+#ifdef REDIS_TEST
+int hi_sdsTest(int argc, char *argv[]);
+#endif
+
+#endif /* HIREDIS_SDS_H */

src/sdsalloc.h

@@ -0,0 +1,44 @@
+/* SDSLib 2.0 -- A C dynamic strings library
+ *
+ * Copyright (c) 2006-2015, Salvatore Sanfilippo <antirez at gmail dot com>
+ * Copyright (c) 2015, Oran Agra
+ * Copyright (c) 2015, Redis Labs, Inc
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/* SDS allocator selection.
+ *
+ * This file is used in order to change the SDS allocator at compile time.
+ * Just define the following defines to what you want to use. Also add
+ * the include of your alternate allocator if needed (not needed in order
+ * to use the default libc allocator). */
+
+#include "alloc.h"
+
+#define hi_s_malloc hi_malloc
+#define hi_s_realloc hi_realloc
+#define hi_s_free hi_free

src/sdscompat.h

@@ -0,0 +1,94 @@
+/*
+ * Copyright (c) 2020, Michael Grunder <michael dot grunder at gmail dot com>
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/*
+ * SDS compatibility header.
+ *
+ * This simple file maps sds types and calls to their unique hiredis symbol names.
+ * It's useful when we build Hiredis as a dependency of Redis and want to call
+ * Hiredis' sds symbols rather than the ones built into Redis, as the libraries
+ * have slightly diverged and could cause hard to track down ABI incompatibility
+ * bugs.
+ *
+ */
+
+#ifndef HIREDIS_SDS_COMPAT
+#define HIREDIS_SDS_COMPAT
+
+#define sds hisds
+
+#define sdslen hi_sdslen
+#define sdsavail hi_sdsavail
+#define sdssetlen hi_sdssetlen
+#define sdsinclen hi_sdsinclen
+#define sdsalloc hi_sdsalloc
+#define sdssetalloc hi_sdssetalloc
+
+#define sdsAllocPtr hi_sdsAllocPtr
+#define sdsAllocSize hi_sdsAllocSize
+#define sdscat hi_sdscat
+#define sdscatfmt hi_sdscatfmt
+#define sdscatlen hi_sdscatlen
+#define sdscatprintf hi_sdscatprintf
+#define sdscatrepr hi_sdscatrepr
+#define sdscatsds hi_sdscatsds
+#define sdscatvprintf hi_sdscatvprintf
+#define sdsclear hi_sdsclear
+#define sdscmp hi_sdscmp
+#define sdscpy hi_sdscpy
+#define sdscpylen hi_sdscpylen
+#define sdsdup hi_sdsdup
+#define sdsempty hi_sdsempty
+#define sds_free hi_sds_free
+#define sdsfree hi_sdsfree
+#define sdsfreesplitres hi_sdsfreesplitres
+#define sdsfromlonglong hi_sdsfromlonglong
+#define sdsgrowzero hi_sdsgrowzero
+#define sdsIncrLen hi_sdsIncrLen
+#define sdsjoin hi_sdsjoin
+#define sdsjoinsds hi_sdsjoinsds
+#define sdsll2str hi_sdsll2str
+#define sdsMakeRoomFor hi_sdsMakeRoomFor
+#define sds_malloc hi_sds_malloc
+#define sdsmapchars hi_sdsmapchars
+#define sdsnew hi_sdsnew
+#define sdsnewlen hi_sdsnewlen
+#define sdsrange hi_sdsrange
+#define sds_realloc hi_sds_realloc
+#define sdsRemoveFreeSpace hi_sdsRemoveFreeSpace
+#define sdssplitargs hi_sdssplitargs
+#define sdssplitlen hi_sdssplitlen
+#define sdstolower hi_sdstolower
+#define sdstoupper hi_sdstoupper
+#define sdstrim hi_sdstrim
+#define sdsull2str hi_sdsull2str
+#define sdsupdatelen hi_sdsupdatelen
+
+#endif /* HIREDIS_SDS_COMPAT */

src/ssl.c

@@ -0,0 +1,568 @@
+/*
+ * Copyright (c) 2009-2011, Salvatore Sanfilippo <antirez at gmail dot com>
+ * Copyright (c) 2010-2011, Pieter Noordhuis <pcnoordhuis at gmail dot com>
+ * Copyright (c) 2019, Redis Labs
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "hiredis.h"
+#include "async.h"
+
+#include <assert.h>
+#include <errno.h>
+#include <string.h>
+#ifdef _WIN32
+#include <windows.h>
+#include <wincrypt.h>
+#else
+#include <pthread.h>
+#endif
+
+#include <openssl/ssl.h>
+#include <openssl/err.h>
+
+#include "async_private.h"
+#include "hiredis_ssl.h"
+
+void __redisSetError(redisContext *c, int type, const char *str);
+
+struct redisSSLContext {
+    /* Associated OpenSSL SSL_CTX as created by redisCreateSSLContext() */
+    SSL_CTX *ssl_ctx;
+
+    /* Requested SNI, or NULL */
+    char *server_name;
+};
+
+/* The SSL connection context is attached to SSL/TLS connections as a privdata. */
+typedef struct redisSSL {
+    /**
+     * OpenSSL SSL object.
+     */
+    SSL *ssl;
+
+    /**
+     * SSL_write() requires to be called again with the same arguments it was
+     * previously called with in the event of an SSL_read/SSL_write situation
+     */
+    size_t lastLen;
+
+    /** Whether the SSL layer requires read (possibly before a write) */
+    int wantRead;
+
+    /**
+     * Whether a write was requested prior to a read. If set, the write()
+     * should resume whenever a read takes place, if possible
+     */
+    int pendingWrite;
+} redisSSL;
+
+/* Forward declaration */
+redisContextFuncs redisContextSSLFuncs;
+
+/**
+ * OpenSSL global initialization and locking handling callbacks.
+ * Note that this is only required for OpenSSL < 1.1.0.
+ */
+
+#if OPENSSL_VERSION_NUMBER < 0x10100000L
+#define HIREDIS_USE_CRYPTO_LOCKS
+#endif
+
+#ifdef HIREDIS_USE_CRYPTO_LOCKS
+#ifdef _WIN32
+typedef CRITICAL_SECTION sslLockType;
+static void sslLockInit(sslLockType* l) {
+    InitializeCriticalSection(l);
+}
+static void sslLockAcquire(sslLockType* l) {
+    EnterCriticalSection(l);
+}
+static void sslLockRelease(sslLockType* l) {
+    LeaveCriticalSection(l);
+}
+#else
+typedef pthread_mutex_t sslLockType;
+static void sslLockInit(sslLockType *l) {
+    pthread_mutex_init(l, NULL);
+}
+static void sslLockAcquire(sslLockType *l) {
+    pthread_mutex_lock(l);
+}
+static void sslLockRelease(sslLockType *l) {
+    pthread_mutex_unlock(l);
+}
+#endif
+
+static sslLockType* ossl_locks;
+
+static void opensslDoLock(int mode, int lkid, const char *f, int line) {
+    sslLockType *l = ossl_locks + lkid;
+
+    if (mode & CRYPTO_LOCK) {
+        sslLockAcquire(l);
+    } else {
+        sslLockRelease(l);
+    }
+
+    (void)f;
+    (void)line;
+}
+
+static int initOpensslLocks(void) {
+    unsigned ii, nlocks;
+    if (CRYPTO_get_locking_callback() != NULL) {
+        /* Someone already set the callback before us. Don't destroy it! */
+        return REDIS_OK;
+    }
+    nlocks = CRYPTO_num_locks();
+    ossl_locks = hi_malloc(sizeof(*ossl_locks) * nlocks);
+    if (ossl_locks == NULL)
+        return REDIS_ERR;
+
+    for (ii = 0; ii < nlocks; ii++) {
+        sslLockInit(ossl_locks + ii);
+    }
+    CRYPTO_set_locking_callback(opensslDoLock);
+    return REDIS_OK;
+}
+#endif /* HIREDIS_USE_CRYPTO_LOCKS */
+
+int redisInitOpenSSL(void)
+{
+    SSL_library_init();
+#ifdef HIREDIS_USE_CRYPTO_LOCKS
+    initOpensslLocks();
+#endif
+
+    return REDIS_OK;
+}
+
+/**
+ * redisSSLContext helper context destruction.
+ */
+
+const char *redisSSLContextGetError(redisSSLContextError error)
+{
+    switch (error) {
+        case REDIS_SSL_CTX_NONE:
+            return "No Error";
+        case REDIS_SSL_CTX_CREATE_FAILED:
+            return "Failed to create OpenSSL SSL_CTX";
+        case REDIS_SSL_CTX_CERT_KEY_REQUIRED:
+            return "Client cert and key must both be specified or skipped";
+        case REDIS_SSL_CTX_CA_CERT_LOAD_FAILED:
+            return "Failed to load CA Certificate or CA Path";
+        case REDIS_SSL_CTX_CLIENT_CERT_LOAD_FAILED:
+            return "Failed to load client certificate";
+        case REDIS_SSL_CTX_PRIVATE_KEY_LOAD_FAILED:
+            return "Failed to load private key";
+        case REDIS_SSL_CTX_OS_CERTSTORE_OPEN_FAILED:
+            return "Failed to open system certifcate store";
+        case REDIS_SSL_CTX_OS_CERT_ADD_FAILED:
+            return "Failed to add CA certificates obtained from system to the SSL context";
+        default:
+            return "Unknown error code";
+    }
+}
+
+void redisFreeSSLContext(redisSSLContext *ctx)
+{
+    if (!ctx)
+        return;
+
+    if (ctx->server_name) {
+        hi_free(ctx->server_name);
+        ctx->server_name = NULL;
+    }
+
+    if (ctx->ssl_ctx) {
+        SSL_CTX_free(ctx->ssl_ctx);
+        ctx->ssl_ctx = NULL;
+    }
+
+    hi_free(ctx);
+}
+
+
+/**
+ * redisSSLContext helper context initialization.
+ */
+
+redisSSLContext *redisCreateSSLContext(const char *cacert_filename, const char *capath,
+        const char *cert_filename, const char *private_key_filename,
+        const char *server_name, redisSSLContextError *error)
+{
+#ifdef _WIN32
+    HCERTSTORE win_store = NULL;
+    PCCERT_CONTEXT win_ctx = NULL;
+#endif
+
+    redisSSLContext *ctx = hi_calloc(1, sizeof(redisSSLContext));
+    if (ctx == NULL)
+        goto error;
+
+    ctx->ssl_ctx = SSL_CTX_new(SSLv23_client_method());
+    if (!ctx->ssl_ctx) {
+        if (error) *error = REDIS_SSL_CTX_CREATE_FAILED;
+        goto error;
+    }
+
+    SSL_CTX_set_options(ctx->ssl_ctx, SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3);
+    SSL_CTX_set_verify(ctx->ssl_ctx, SSL_VERIFY_PEER, NULL);
+
+    if ((cert_filename != NULL && private_key_filename == NULL) ||
+            (private_key_filename != NULL && cert_filename == NULL)) {
+        if (error) *error = REDIS_SSL_CTX_CERT_KEY_REQUIRED;
+        goto error;
+    }
+
+    if (capath || cacert_filename) {
+#ifdef _WIN32
+        if (0 == strcmp(cacert_filename, "wincert")) {
+            win_store = CertOpenSystemStore(NULL, "Root");
+            if (!win_store) {
+                if (error) *error = REDIS_SSL_CTX_OS_CERTSTORE_OPEN_FAILED;
+                goto error;
+            }
+            X509_STORE* store = SSL_CTX_get_cert_store(ctx->ssl_ctx);
+            while (win_ctx = CertEnumCertificatesInStore(win_store, win_ctx)) {
+                X509* x509 = NULL;
+                x509 = d2i_X509(NULL, (const unsigned char**)&win_ctx->pbCertEncoded, win_ctx->cbCertEncoded);
+                if (x509) {
+                    if ((1 != X509_STORE_add_cert(store, x509)) ||
+                        (1 != SSL_CTX_add_client_CA(ctx->ssl_ctx, x509)))
+                    {
+                        if (error) *error = REDIS_SSL_CTX_OS_CERT_ADD_FAILED;
+                        goto error;
+                    }
+                    X509_free(x509);
+                }
+            }
+            CertFreeCertificateContext(win_ctx);
+            CertCloseStore(win_store, 0);
+        } else
+#endif
+        if (!SSL_CTX_load_verify_locations(ctx->ssl_ctx, cacert_filename, capath)) {
+            if (error) *error = REDIS_SSL_CTX_CA_CERT_LOAD_FAILED;
+            goto error;
+        }
+    }
+
+    if (cert_filename) {
+        if (!SSL_CTX_use_certificate_chain_file(ctx->ssl_ctx, cert_filename)) {
+            if (error) *error = REDIS_SSL_CTX_CLIENT_CERT_LOAD_FAILED;
+            goto error;
+        }
+        if (!SSL_CTX_use_PrivateKey_file(ctx->ssl_ctx, private_key_filename, SSL_FILETYPE_PEM)) {
+            if (error) *error = REDIS_SSL_CTX_PRIVATE_KEY_LOAD_FAILED;
+            goto error;
+        }
+    }
+
+    if (server_name)
+        ctx->server_name = hi_strdup(server_name);
+
+    return ctx;
+
+error:
+#ifdef _WIN32
+    CertFreeCertificateContext(win_ctx);
+    CertCloseStore(win_store, 0);
+#endif
+    redisFreeSSLContext(ctx);
+    return NULL;
+}
+
+/**
+ * SSL Connection initialization.
+ */
+
+
+static int redisSSLConnect(redisContext *c, SSL *ssl) {
+    if (c->privctx) {
+        __redisSetError(c, REDIS_ERR_OTHER, "redisContext was already associated");
+        return REDIS_ERR;
+    }
+
+    redisSSL *rssl = hi_calloc(1, sizeof(redisSSL));
+    if (rssl == NULL) {
+        __redisSetError(c, REDIS_ERR_OOM, "Out of memory");
+        return REDIS_ERR;
+    }
+
+    c->funcs = &redisContextSSLFuncs;
+    rssl->ssl = ssl;
+
+    SSL_set_mode(rssl->ssl, SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER);
+    SSL_set_fd(rssl->ssl, c->fd);
+    SSL_set_connect_state(rssl->ssl);
+
+    ERR_clear_error();
+    int rv = SSL_connect(rssl->ssl);
+    if (rv == 1) {
+        c->privctx = rssl;
+        return REDIS_OK;
+    }
+
+    rv = SSL_get_error(rssl->ssl, rv);
+    if (((c->flags & REDIS_BLOCK) == 0) &&
+        (rv == SSL_ERROR_WANT_READ || rv == SSL_ERROR_WANT_WRITE)) {
+        c->privctx = rssl;
+        return REDIS_OK;
+    }
+
+    if (c->err == 0) {
+        char err[512];
+        if (rv == SSL_ERROR_SYSCALL)
+            snprintf(err,sizeof(err)-1,"SSL_connect failed: %s",strerror(errno));
+        else {
+            unsigned long e = ERR_peek_last_error();
+            snprintf(err,sizeof(err)-1,"SSL_connect failed: %s",
+                    ERR_reason_error_string(e));
+        }
+        __redisSetError(c, REDIS_ERR_IO, err);
+    }
+
+    hi_free(rssl);
+    return REDIS_ERR;
+}
+
+/**
+ * A wrapper around redisSSLConnect() for users who manage their own context and
+ * create their own SSL object.
+ */
+
+int redisInitiateSSL(redisContext *c, SSL *ssl) {
+    return redisSSLConnect(c, ssl);
+}
+
+/**
+ * A wrapper around redisSSLConnect() for users who use redisSSLContext and don't
+ * manage their own SSL objects.
+ */
+
+int redisInitiateSSLWithContext(redisContext *c, redisSSLContext *redis_ssl_ctx)
+{
+    if (!c || !redis_ssl_ctx)
+        return REDIS_ERR;
+
+    /* We want to verify that redisSSLConnect() won't fail on this, as it will
+     * not own the SSL object in that case and we'll end up leaking.
+     */
+    if (c->privctx)
+        return REDIS_ERR;
+
+    SSL *ssl = SSL_new(redis_ssl_ctx->ssl_ctx);
+    if (!ssl) {
+        __redisSetError(c, REDIS_ERR_OTHER, "Couldn't create new SSL instance");
+        goto error;
+    }
+
+    if (redis_ssl_ctx->server_name) {
+        if (!SSL_set_tlsext_host_name(ssl, redis_ssl_ctx->server_name)) {
+            __redisSetError(c, REDIS_ERR_OTHER, "Failed to set server_name/SNI");
+            goto error;
+        }
+    }
+
+    if (redisSSLConnect(c, ssl) != REDIS_OK) {
+        goto error;
+    }
+
+    return REDIS_OK;
+
+error:
+    if (ssl)
+        SSL_free(ssl);
+    return REDIS_ERR;
+}
+
+static int maybeCheckWant(redisSSL *rssl, int rv) {
+    /**
+     * If the error is WANT_READ or WANT_WRITE, the appropriate flags are set
+     * and true is returned. False is returned otherwise
+     */
+    if (rv == SSL_ERROR_WANT_READ) {
+        rssl->wantRead = 1;
+        return 1;
+    } else if (rv == SSL_ERROR_WANT_WRITE) {
+        rssl->pendingWrite = 1;
+        return 1;
+    } else {
+        return 0;
+    }
+}
+
+/**
+ * Implementation of redisContextFuncs for SSL connections.
+ */
+
+static void redisSSLFree(void *privctx){
+    redisSSL *rsc = privctx;
+
+    if (!rsc) return;
+    if (rsc->ssl) {
+        SSL_free(rsc->ssl);
+        rsc->ssl = NULL;
+    }
+    hi_free(rsc);
+}
+
+static ssize_t redisSSLRead(redisContext *c, char *buf, size_t bufcap) {
+    redisSSL *rssl = c->privctx;
+
+    int nread = SSL_read(rssl->ssl, buf, bufcap);
+    if (nread > 0) {
+        return nread;
+    } else if (nread == 0) {
+        __redisSetError(c, REDIS_ERR_EOF, "Server closed the connection");
+        return -1;
+    } else {
+        int err = SSL_get_error(rssl->ssl, nread);
+        if (c->flags & REDIS_BLOCK) {
+            /**
+             * In blocking mode, we should never end up in a situation where
+             * we get an error without it being an actual error, except
+             * in the case of EINTR, which can be spuriously received from
+             * debuggers or whatever.
+             */
+            if (errno == EINTR) {
+                return 0;
+            } else {
+                const char *msg = NULL;
+                if (errno == EAGAIN) {
+                    msg = "Resource temporarily unavailable";
+                }
+                __redisSetError(c, REDIS_ERR_IO, msg);
+                return -1;
+            }
+        }
+
+        /**
+         * We can very well get an EWOULDBLOCK/EAGAIN, however
+         */
+        if (maybeCheckWant(rssl, err)) {
+            return 0;
+        } else {
+            __redisSetError(c, REDIS_ERR_IO, NULL);
+            return -1;
+        }
+    }
+}
+
+static ssize_t redisSSLWrite(redisContext *c) {
+    redisSSL *rssl = c->privctx;
+
+    size_t len = rssl->lastLen ? rssl->lastLen : hi_sdslen(c->obuf);
+    int rv = SSL_write(rssl->ssl, c->obuf, len);
+
+    if (rv > 0) {
+        rssl->lastLen = 0;
+    } else if (rv < 0) {
+        rssl->lastLen = len;
+
+        int err = SSL_get_error(rssl->ssl, rv);
+        if ((c->flags & REDIS_BLOCK) == 0 && maybeCheckWant(rssl, err)) {
+            return 0;
+        } else {
+            __redisSetError(c, REDIS_ERR_IO, NULL);
+            return -1;
+        }
+    }
+    return rv;
+}
+
+static void redisSSLAsyncRead(redisAsyncContext *ac) {
+    int rv;
+    redisSSL *rssl = ac->c.privctx;
+    redisContext *c = &ac->c;
+
+    rssl->wantRead = 0;
+
+    if (rssl->pendingWrite) {
+        int done;
+
+        /* This is probably just a write event */
+        rssl->pendingWrite = 0;
+        rv = redisBufferWrite(c, &done);
+        if (rv == REDIS_ERR) {
+            __redisAsyncDisconnect(ac);
+            return;
+        } else if (!done) {
+            _EL_ADD_WRITE(ac);
+        }
+    }
+
+    rv = redisBufferRead(c);
+    if (rv == REDIS_ERR) {
+        __redisAsyncDisconnect(ac);
+    } else {
+        _EL_ADD_READ(ac);
+        redisProcessCallbacks(ac);
+    }
+}
+
+static void redisSSLAsyncWrite(redisAsyncContext *ac) {
+    int rv, done = 0;
+    redisSSL *rssl = ac->c.privctx;
+    redisContext *c = &ac->c;
+
+    rssl->pendingWrite = 0;
+    rv = redisBufferWrite(c, &done);
+    if (rv == REDIS_ERR) {
+        __redisAsyncDisconnect(ac);
+        return;
+    }
+
+    if (!done) {
+        if (rssl->wantRead) {
+            /* Need to read-before-write */
+            rssl->pendingWrite = 1;
+            _EL_DEL_WRITE(ac);
+        } else {
+            /* No extra reads needed, just need to write more */
+            _EL_ADD_WRITE(ac);
+        }
+    } else {
+        /* Already done! */
+        _EL_DEL_WRITE(ac);
+    }
+
+    /* Always reschedule a read */
+    _EL_ADD_READ(ac);
+}
+
+redisContextFuncs redisContextSSLFuncs = {
+    .free_privctx = redisSSLFree,
+    .async_read = redisSSLAsyncRead,
+    .async_write = redisSSLAsyncWrite,
+    .read = redisSSLRead,
+    .write = redisSSLWrite
+};
+