From 4c52aa9faa4d6e3ba2243a4f45563cb4a1439bb8 Mon Sep 17 00:00:00 2001
From: SUN <jianyungsun@gmail.com>
Date: Sun, 20 Jun 2021 16:34:04 +0800
Subject: [PATCH] chdir to dir before fopen logfile in
 loadServerConfigFromString() (#6741)

Open the log file only after parsing the entire config file, so that it's
location isn't dependent on the order of configs (`dir` and `logfile`).
Also solves the problem of creating multiple log files if the `logfile`
directive appears many times in the config file.
---
 src/config.c | 27 ++++++++++++++-------------
 1 file changed, 14 insertions(+), 13 deletions(-)

diff --git a/src/config.c b/src/config.c
index 29de26c5b..40003f270 100644
--- a/src/config.c
+++ b/src/config.c
@@ -492,21 +492,8 @@ void loadServerConfigFromString(char *config) {
                 goto loaderr;
             }
         } else if (!strcasecmp(argv[0],"logfile") && argc == 2) {
-            FILE *logfp;
-
             zfree(server.logfile);
             server.logfile = zstrdup(argv[1]);
-            if (server.logfile[0] != '\0') {
-                /* Test if we are able to open the file. The server will not
-                 * be able to abort just for this problem later... */
-                logfp = fopen(server.logfile,"a");
-                if (logfp == NULL) {
-                    err = sdscatprintf(sdsempty(),
-                        "Can't open the log file: %s", strerror(errno));
-                    goto loaderr;
-                }
-                fclose(logfp);
-            }
         } else if (!strcasecmp(argv[0],"include") && argc == 2) {
             loadServerConfig(argv[1], 0, NULL);
         } else if ((!strcasecmp(argv[0],"slaveof") ||
@@ -615,6 +602,20 @@ void loadServerConfigFromString(char *config) {
         sdsfreesplitres(argv,argc);
     }
 
+    if (server.logfile[0] != '\0') {
+        FILE *logfp;
+
+        /* Test if we are able to open the file. The server will not
+         * be able to abort just for this problem later... */
+        logfp = fopen(server.logfile,"a");
+        if (logfp == NULL) {
+            err = sdscatprintf(sdsempty(),
+                               "Can't open the log file: %s", strerror(errno));
+            goto loaderr;
+        }
+        fclose(logfp);
+    }
+
     /* Sanity checks. */
     if (server.cluster_enabled && server.masterhost) {
         linenum = slaveof_linenum;