Fix SENTINEL SET config rewrite test (#10232)

Change the sentinel config file to a directory in SENTINEL SET test.
So it will now fail on the `rename` in `rewriteConfigOverwriteFile`.

The test used to set the sentinel config file permissions to `000` to
simulate failure. But it fails on centos7 / freebsd / alpine. (introduced in #10151)

Other changes:
1. More error messages after the config rewrite failure.
2. Modify arg name `force_all` in `rewriteConfig` to `force_write`. (was rename in #9304)
3. Fix a typo in debug quicklist-packed-threshold, then -> than. (#9357)

src/debug.c

@@ -825,7 +825,7 @@ NULL
         int memerr;
         unsigned long long sz = memtoull((const char *)c->argv[2]->ptr, &memerr);
         if (memerr || !quicklistisSetPackedThreshold(sz)) {
-            addReplyError(c, "argument must be a memory value bigger then 1 and smaller than 4gb");
+            addReplyError(c, "argument must be a memory value bigger than 1 and smaller than 4gb");
         } else {
             addReply(c,shared.ok);
         }
@@ -926,7 +926,7 @@ NULL
     } else if (!strcasecmp(c->argv[1]->ptr,"config-rewrite-force-all") && c->argc == 2)
     {
         if (rewriteConfig(server.configfile, 1) == -1)
-            addReplyError(c, "CONFIG-REWRITE-FORCE-ALL failed");
+            addReplyErrorFormat(c, "CONFIG-REWRITE-FORCE-ALL failed: %s", strerror(errno));
         else
             addReply(c, shared.ok);
     } else if(!strcasecmp(c->argv[1]->ptr,"client-eviction") && c->argc == 2) {

src/sentinel.c

@@ -2286,7 +2286,7 @@ werr:
  */
 static void sentinelFlushConfigAndReply(client *c) {
     if (sentinelFlushConfig() == C_ERR)
-        addReplyErrorFormat(c,"Failed to save config file");
+        addReplyError(c, "Failed to save config file. Check server logs.");
     else
         addReply(c, shared.ok);
 }

src/server.c

@@ -1891,7 +1891,7 @@ int restartServer(int flags, mstime_t delay) {
         rewriteConfig(server.configfile, 0) == -1)
     {
         serverLog(LL_WARNING,"Can't restart: configuration rewrite process "
-                             "failed");
+                             "failed: %s", strerror(errno));
         return C_ERR;
     }
 

src/server.h

@@ -2932,7 +2932,7 @@ void resetServerSaveParams(void);
 struct rewriteConfigState; /* Forward declaration to export API. */
 void rewriteConfigRewriteLine(struct rewriteConfigState *state, const char *option, sds line, int force);
 void rewriteConfigMarkAsProcessed(struct rewriteConfigState *state, const char *option);
-int rewriteConfig(char *path, int force_all);
+int rewriteConfig(char *path, int force_write);
 void initConfigValues();
 sds getConfigDebugInfo();
 int allowProtectedAction(int config, client *c);

tests/sentinel/tests/03-runtime-reconf.tcl

@@ -51,10 +51,15 @@ test "Sentinel Set with other error situations" {
    set update_quorum [expr $origin_quorum+1]
    set sentinel_id 0
    set configfilename [file join "sentinel_$sentinel_id" "sentinel.conf"]
-   exec chmod 000 $configfilename
+   set configfilename_bak [file join "sentinel_$sentinel_id" "sentinel.conf.bak"]
+
+   file rename $configfilename $configfilename_bak
+   file mkdir $configfilename
 
    catch {[S 0 SENTINEL SET mymaster quorum $update_quorum]} err
-   exec chmod 644 $configfilename
-   assert_equal "ERR Failed to save config file" $err
-}
 
+   file delete $configfilename
+   file rename $configfilename_bak $configfilename
+
+   assert_match "ERR Failed to save config file*" $err
+}