Drop __redis_strerror_r

Since _GNU_SOURCE is now guaranteed to be unset, it is no longer
necessary to support the GNU-specific version of strerror_r.

Drop __redis_strerror_r from the header, and call strerror_r directly.
This breaks any external users of this macro, but they shouldn't have
been using it in  the first place.

Signed-off-by: Justin Brewer <jzb0012@auburn.edu>

hiredis.c

@@ -581,7 +581,7 @@ void __redisSetError(redisContext *c, int type, const char *str) {
     } else {
         /* Only REDIS_ERR_IO may lack a description! */
         assert(type == REDIS_ERR_IO);
-        __redis_strerror_r(errno, c->errstr, sizeof(c->errstr));
+        strerror_r(errno, c->errstr, sizeof(c->errstr));
     }
 }
 

hiredis.h

@@ -80,30 +80,6 @@
  * SO_REUSEADDR is being used. */
 #define REDIS_CONNECT_RETRIES  10
 
-/* strerror_r has two completely different prototypes and behaviors
- * depending on system issues, so we need to operate on the error buffer
- * differently depending on which strerror_r we're using. */
-#ifndef _GNU_SOURCE
-/* "regular" POSIX strerror_r that does the right thing. */
-#define __redis_strerror_r(errno, buf, len)                                    \
-    do {                                                                       \
-        strerror_r((errno), (buf), (len));                                     \
-    } while (0)
-#else
-/* "bad" GNU strerror_r we need to clean up after. */
-#define __redis_strerror_r(errno, buf, len)                                    \
-    do {                                                                       \
-        char *err_str = strerror_r((errno), (buf), (len));                     \
-        /* If return value _isn't_ the start of the buffer we passed in,       \
-         * then GNU strerror_r returned an internal static buffer and we       \
-         * need to copy the result into our private buffer. */                 \
-        if (err_str != (buf)) {                                                \
-            strncpy((buf), err_str, ((len) - 1));                              \
-            (buf)[(len)-1] = '\0';                                               \
-        }                                                                      \
-    } while (0)
-#endif
-
 #ifdef __cplusplus
 extern "C" {
 #endif

net.c

@@ -71,7 +71,7 @@ static void __redisSetErrorFromErrno(redisContext *c, int type, const char *pref
 
     if (prefix != NULL)
         len = snprintf(buf,sizeof(buf),"%s: ",prefix);
-    __redis_strerror_r(errorno, (char *)(buf + len), sizeof(buf) - len);
+    strerror_r(errorno, (char *)(buf + len), sizeof(buf) - len);
     __redisSetError(c,type,buf);
 }