When an asynchronous hiredis connection subscribes to a Pub/Sub channel
and gets an error, and in other related conditions, the function
redisProcessCallbacks() enters a code path where the link is
disconnected, however the function returns before freeing the allocated
reply object. This causes a memory leak. The memory leak was trivial to
trigger in Redis Sentinel, which uses hiredis, every time we tried to
subscribe to an instance that required a password, in case the Sentinel
was configured either with the wrong password or without password at
all. In this case, the -AUTH error caused the leaking code path to be
executed.
Previously, redisvAppendCommand() would return OOM even with formatting
errors. Now we use OTHER with an error string telling the user the
error was formatting related, not memory related.
This also fixes a potentially worse bug where were would pass error result
of -1 as an actual length to another function taking an unsigned length,
which would result in crash/overallocation/errors. Now for that case,
we just return an error immediately and stop processing the command.
Fixes#177
redisAsyncInitialize() can return NULL, but then we pass
the return value from redisAsyncInitialize() into something
dereferencing the return value, which can cause crashies.
[This introduces some new API functions.]
* Adds new flag to the connection context indicating SO_REUSEADDR
should be set.
* Adds max number of retries constant for when connect() hits
EADDRNOTAVAIL.
* Adds new function, redisAsyncConnectBindWithReuse(), letting
clients enable this functionality.
[Removed trailing whitespace in new header lines.]
Closes#264
OK, perhaps the second time is a charm. I forgot that I had
hiredis forked from a long time ago, so the initial pull
request was hosed. :)
* Pulled in sdscatfmt() from Redis, and modified it to accept a
size_t (%T) style format specifier.
* Pulled in sdsll2str() and sdsull2str() from Redis (needed by
sdscatfmt).
* Added a new method, redisFormatSdsCommandArgv() which takes
and sds* as the target, rather than char* (and uses sdscatfmt
instead of sprintf for the construction).
I get roughly the following improvement:
Old: 1.044806
New: 0.481620
The benchmark code itself can be found here:
https://gist.github.com/michael-grunder/c92ef31bb632b3d0ad81Closes#260
Some environments require binding to specific source addresses instead
of letting the system determine which IP a connection should originate
from.
Closes#233
All the assignments to cb are inside conditionals, so it's
vaguely possible it never gets initialized before we try
to read from it with (cb.fn == NULL).
Condition discovered with scan-build.
Closes#229
With all the async connects and disconnects and error handling
going on in hiredis, we need to centralize how we close our fd
and set it so it doesn't get re-closed. Prior to this commit,
sometimes we'd close(fd), run an async error handler, then
call close(fd) again.
To stop multiple closes, we now set fd to -1 after we free it,
but that requires not passing fd as an independent argument to
functions.
This commit moves all fd usage to c->fd. Since the context
has a fd field and all functions receive the context, it makes
more sense to use the fd inside of c instead of passing along fd
as an independent argument.
Also, by only using c->fd, we can set c->fd after we close it to
signify we shouldn't re-close the same fd again.
This does change one semi-public interface function redisCheckSocketError()
to only take (context) instead of (context, fd). A search on github
returned zero occasions of people using redisCheckSocketError()
outside of net.{c,h} in hiredis itself.
Commit inspired by the bug report at:
https://groups.google.com/forum/#!topic/redis-db/mQm46XkIPOY
Thanks go out to Thijs for trying high-frequency reconnects on
a host that isn't there.
Closes#230
This commit adds a status argument to the connect callback. It will be
called in the event of an unsuccessful connection as well, where the
status argument is set to REDIS_ERR. It is set to REDIS_OK otherwise.
To make sure that these functions can also be called from functions
other than command callbacks, the flag IN_CALLBACK is introduced that
holds whether the context is currently executing a callback. If so,
redisAsyncFree() and redisAsyncDisconnect() should delegate their task
to the reply processor to avoid segfaults.
