Cleanup: createAOFClient uses createClient to avoid overlooked mismatches (#9338)

AOF fake client creation (createAOFClient) was doing similar work as createClient,
with some minor differences, most of which unintended, this was dangerous and
meant that many changes to createClient should have always been reflected to aof.c

This cleanup changes createAOFClient to call createClient with NULL, like we
do in module.c and elsewhere.

src/aof.c

@@ -42,6 +42,7 @@
 
 void aofUpdateCurrentSize(void);
 void aofClosePipes(void);
+void freeClientArgv(client *c);
 
 /* ----------------------------------------------------------------------------
  * AOF rewrite buffer implementation.
@@ -639,21 +640,9 @@ void feedAppendOnlyFile(int dictid, robj **argv, int argc) {
 /* In Redis commands are always executed in the context of a client, so in
  * order to load the append only file we need to create a fake client. */
 struct client *createAOFClient(void) {
-    struct client *c = zmalloc(sizeof(*c));
+    struct client *c = createClient(NULL);
 
-    selectDb(c,0);
     c->id = CLIENT_ID_AOF; /* So modules can identify it's the AOF client. */
-    c->conn = NULL;
-    c->name = NULL;
-    c->querybuf = sdsempty();
-    c->querybuf_peak = 0;
-    c->argc = 0;
-    c->argv = NULL;
-    c->original_argc = 0;
-    c->original_argv = NULL;
-    c->argv_len_sum = 0;
-    c->bufpos = 0;
-    c->buf_usable_size = zmalloc_usable_size(c)-offsetof(client,buf);
 
     /*
      * The AOF client should never be blocked (unlike master
@@ -666,42 +655,12 @@ struct client *createAOFClient(void) {
      */
     c->flags = CLIENT_DENY_BLOCKING;
 
-    c->btype = BLOCKED_NONE;
     /* We set the fake client as a slave waiting for the synchronization
      * so that Redis will not try to send replies to this client. */
     c->replstate = SLAVE_STATE_WAIT_BGSAVE_START;
-    c->reply = listCreate();
-    c->reply_bytes = 0;
-    c->obuf_soft_limit_reached_time = 0;
-    c->watched_keys = listCreate();
-    c->peerid = NULL;
-    c->sockname = NULL;
-    c->resp = 2;
-    c->user = NULL;
-    listSetFreeMethod(c->reply,freeClientReplyValue);
-    listSetDupMethod(c->reply,dupClientReplyValue);
-    initClientMultiState(c);
     return c;
 }
 
-void freeFakeClientArgv(struct client *c) {
-    int j;
-
-    for (j = 0; j < c->argc; j++)
-        decrRefCount(c->argv[j]);
-    zfree(c->argv);
-    c->argv_len_sum = 0;
-}
-
-void freeFakeClient(struct client *c) {
-    sdsfree(c->querybuf);
-    listRelease(c->reply);
-    listRelease(c->watched_keys);
-    freeClientMultiState(c);
-    freeClientOriginalArgv(c);
-    zfree(c);
-}
-
 /* Replay the append log file. On success AOF_OK is returned,
  * otherwise, one of the following is returned:
  * AOF_OPEN_ERR: Failed to open the AOF file.
@@ -806,7 +765,7 @@ int loadAppendOnlyFile(char *filename) {
             char *readres = fgets(buf,sizeof(buf),fp);
             if (readres == NULL || buf[0] != '$') {
                 fakeClient->argc = j; /* Free up to j-1. */
-                freeFakeClientArgv(fakeClient);
+                freeClientArgv(fakeClient);
                 if (readres == NULL)
                     goto readerr;
                 else
@@ -819,7 +778,7 @@ int loadAppendOnlyFile(char *filename) {
             if (len && fread(argsds,len,1,fp) == 0) {
                 sdsfree(argsds);
                 fakeClient->argc = j; /* Free up to j-1. */
-                freeFakeClientArgv(fakeClient);
+                freeClientArgv(fakeClient);
                 goto readerr;
             }
             argv[j] = createObject(OBJ_STRING,argsds);
@@ -827,7 +786,7 @@ int loadAppendOnlyFile(char *filename) {
             /* Discard CRLF. */
             if (fread(buf,2,1,fp) == 0) {
                 fakeClient->argc = j+1; /* Free up to j. */
-                freeFakeClientArgv(fakeClient);
+                freeClientArgv(fakeClient);
                 goto readerr;
             }
         }
@@ -838,7 +797,7 @@ int loadAppendOnlyFile(char *filename) {
             serverLog(LL_WARNING,
                 "Unknown command '%s' reading the append only file",
                 (char*)argv[0]->ptr);
-            freeFakeClientArgv(fakeClient);
+            freeClientArgv(fakeClient);
             ret = AOF_FAILED;
             goto cleanup;
         }
@@ -864,7 +823,9 @@ int loadAppendOnlyFile(char *filename) {
 
         /* Clean up. Command code may have changed argv/argc so we use the
          * argv/argc of the client instead of the local variables. */
-        freeFakeClientArgv(fakeClient);
+        freeClientArgv(fakeClient);
+        zfree(fakeClient->argv);
+        fakeClient->argv = NULL;
         fakeClient->cmd = NULL;
         if (server.aof_load_truncated) valid_up_to = ftello(fp);
         if (server.key_load_delay)
@@ -932,7 +893,7 @@ fmterr: /* Format error. */
     /* fall through to cleanup. */
 
 cleanup:
-    if (fakeClient) freeFakeClient(fakeClient); /* avoid valgrind warning */
+    if (fakeClient) freeClient(fakeClient); /* avoid valgrind warning */
     fclose(fp);
     stopLoading(ret == AOF_OK);
     return ret;

src/networking.c

@@ -1184,7 +1184,7 @@ void freeClientOriginalArgv(client *c) {
     c->original_argc = 0;
 }
 
-static void freeClientArgv(client *c) {
+void freeClientArgv(client *c) {
     int j;
     for (j = 0; j < c->argc; j++)
         decrRefCount(c->argv[j]);