gvsafronov/futriix
1
0
Fork 0
Code Issues Pull Requests Actions 1 Packages Projects Releases Wiki Activity

redis-cli: fix writeConn() buffer handling. (#7749)

Browse Source 
Fix issues with writeConn() which resulted with corruption of the stream by leaving an extra byte in the buffer. The trigger for this is partial writes or write errors which were not experienced on Linux but reported on macOS.
This commit is contained in:
Yossi Gottlieb 2020-09-03 18:15:48 +03:00 committed by GitHub
parent 12f798dc18
commit 58e5feb3f4
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 37 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

43
src/redis-cli.c
View File

@ -6905,21 +6905,52 @@ static ssize_t writeConn(redisContext *c, const char *buf, size_t buf_len)
{ {
int done = 0; int done = 0;
/* Append data to buffer which is *usually* expected to be empty
* but we don't assume that, and write.
*/
c->obuf = sdscatlen(c->obuf, buf, buf_len); c->obuf = sdscatlen(c->obuf, buf, buf_len);
if (redisBufferWrite(c, &done) == REDIS_ERR) { if (redisBufferWrite(c, &done) == REDIS_ERR) {
sdsrange(c->obuf, 0, -(buf_len+1));
if (!(c->flags & REDIS_BLOCK)) if (!(c->flags & REDIS_BLOCK))
errno = EAGAIN; errno = EAGAIN;
/* On error, we assume nothing was written and we roll back the
* buffer to its original state.
*/
if (sdslen(c->obuf) > buf_len)
sdsrange(c->obuf, 0, -(buf_len+1));
else
sdsclear(c->obuf);
return -1; return -1;
} }
size_t left = sdslen(c->obuf); /* If we're done, free up everything. We may have written more than
sdsclear(c->obuf); * buf_len (if c->obuf was not initially empty) but we don't have to
if (!done) { * tell.
return buf_len - left; */
if (done) {
sdsclear(c->obuf);
return buf_len;
} }
return buf_len; /* Write was successful but we have some leftovers which we should
* remove from the buffer.
*
* Do we still have data that was there prior to our buf? If so,
* restore buffer to it's original state and report no new data was
* writen.
*/
if (sdslen(c->obuf) > buf_len) {
sdsrange(c->obuf, 0, -(buf_len+1));
return 0;
}
/* At this point we're sure no prior data is left. We flush the buffer
* and report how much we've written.
*/
size_t left = sdslen(c->obuf);
sdsclear(c->obuf);
return buf_len - left;
} }
/* Read raw bytes through a redisContext. The read operation is not greedy /* Read raw bytes through a redisContext. The read operation is not greedy