Fix redisAppendCommand error result

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

1 files changed, 5 insertions, 0 deletions

diff --git a/async.c b/async.c
index 5acd01c..84480bc 100644
--- a/async.c
+++ b/async.c
@@ -650,6 +650,11 @@ int redisvAsyncCommand(redisAsyncContext *ac, redisCallbackFn *fn, void *privdat
     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);
     free(cmd);
     return status;