From fcb3aef7c424ede2d3f0e58adddd1a84154d29ae Mon Sep 17 00:00:00 2001
From: antirez <antirez@gmail.com>
Date: Tue, 13 Oct 2015 11:08:24 +0200
Subject: [PATCH] DEBUG RESTART/CRASH-AND-RECOVER [delay] implemented.

---
 src/debug.c  | 14 ++++++++++++++
 src/server.c |  3 +++
 2 files changed, 17 insertions(+)

diff --git a/src/debug.c b/src/debug.c
index 704e4bbf..a9644462 100644
--- a/src/debug.c
+++ b/src/debug.c
@@ -261,6 +261,20 @@ void inputCatSds(void *result, const char *str) {
 void debugCommand(client *c) {
     if (!strcasecmp(c->argv[1]->ptr,"segfault")) {
         *((char*)-1) = 'x';
+    } else if (!strcasecmp(c->argv[1]->ptr,"restart") ||
+               !strcasecmp(c->argv[1]->ptr,"crash-and-recover"))
+    {
+        long long delay = 0;
+        if (c->argc >= 3) {
+            if (getLongLongFromObjectOrReply(c, c->argv[2], &delay, NULL)
+                != C_OK) return;
+            if (delay < 0) delay = 0;
+        }
+        int flags = !strcasecmp(c->argv[1]->ptr,"restart") ?
+            (RESTART_SERVER_GRACEFULLY|RESTART_SERVER_CONFIG_REWRITE) :
+             RESTART_SERVER_NONE;
+        restartServer(flags,delay);
+        addReplyError(c,"failed to restart the server. Check server logs.");
     } else if (!strcasecmp(c->argv[1]->ptr,"oom")) {
         void *ptr = zmalloc(ULONG_MAX); /* Should trigger an out of memory. */
         zfree(ptr);
diff --git a/src/server.c b/src/server.c
index 68704faa..c425bb3e 100644
--- a/src/server.c
+++ b/src/server.c
@@ -1579,6 +1579,9 @@ extern char **environ;
 /* Restart the server, executing the same executable that started this
  * instance, with the same arguments and configuration file.
  *
+ * The function is designed to directly call execve() so that the new
+ * server instance will retain the PID of the previous one.
+ *
  * The list of flags, that may be bitwise ORed together, alter the
  * behavior of this function:
  *