From 840ac20855855b134662683ca3e7d9e364d4bca8 Mon Sep 17 00:00:00 2001
From: antirez <antirez@gmail.com>
Date: Wed, 4 May 2016 12:45:55 +0200
Subject: [PATCH] DEBUG command self documentation.

---
 src/debug.c  | 49 ++++++++++++++++++++++++++++++++++++++++++++++++-
 src/server.c |  2 +-
 2 files changed, 49 insertions(+), 2 deletions(-)

diff --git a/src/debug.c b/src/debug.c
index cd0469c7..1e179caf 100644
--- a/src/debug.c
+++ b/src/debug.c
@@ -259,7 +259,54 @@ void inputCatSds(void *result, const char *str) {
 #endif
 
 void debugCommand(client *c) {
-    if (!strcasecmp(c->argv[1]->ptr,"segfault")) {
+    if (c->argc == 1) {
+        addReplyError(c,"You must specify a subcommand for DEBUG. Try DEBUG HELP for info.");
+        return;
+    }
+
+    if (!strcasecmp(c->argv[1]->ptr,"help")) {
+        void *blenp = addDeferredMultiBulkLength(c);
+        int blen = 0;
+        blen++; addReplyStatus(c,
+        "DEBUG <subcommand> arg arg ... arg. Subcommands:");
+        blen++; addReplyStatus(c,
+        "segfault -- Crash the server with sigsegv.");
+        blen++; addReplyStatus(c,
+        "restart  -- Graceful restart: save config, db, restart.");
+        blen++; addReplyStatus(c,
+        "crash-and-recovery <milliseconds> -- Hard crash and restart after <milliseconds> delay.");
+        blen++; addReplyStatus(c,
+        "assert   -- Crash by assertion failed.");
+        blen++; addReplyStatus(c,
+        "reload   -- Save the RDB on disk and reload it back in memory.");
+        blen++; addReplyStatus(c,
+        "loadaof  -- Flush the AOF buffers on disk and reload the AOF in memory.");
+        blen++; addReplyStatus(c,
+        "object <key> -- Show low level info about key and associated value.");
+        blen++; addReplyStatus(c,
+        "sdslen <key> -- Show low level SDS string info representing key and value.");
+        blen++; addReplyStatus(c,
+        "populate <count> [prefix] -- Create <count> string keys named key:<num>. If a prefix is specified is used instead of the 'key' prefix.");
+        blen++; addReplyStatus(c,
+        "digest   -- Outputs an hex signature representing the current DB content.");
+        blen++; addReplyStatus(c,
+        "sleep <seconds> -- Stop the server for <seconds>. Decimals allowed.");
+        blen++; addReplyStatus(c,
+        "set-active-expire (0|1) -- Setting it to 0 disables expiring keys in background when they are not accessed (otherwise the Redis behavior). Setting it to 1 reenables back the default.");
+        blen++; addReplyStatus(c,
+        "lua-always-replicate-commands (0|1) -- Setting it to 1 makes Lua replication defaulting to replicating single commands, without the script having to enable effects replication.");
+        blen++; addReplyStatus(c,
+        "error <string> -- Return a Redis protocol error with <string> as message. Useful for clients unit tests to simulate Redis errors.");
+        blen++; addReplyStatus(c,
+        "structsize -- Return the size of different Redis core C structures.");
+        blen++; addReplyStatus(c,
+        "htstats <dbid> -- Return hash table statistics of the specified Redis database.");
+        blen++; addReplyStatus(c,
+        "jemalloc info  -- Show internal jemalloc statistics.");
+        blen++; addReplyStatus(c,
+        "jemalloc purge -- Force jemalloc to release unused memory.");
+        setDeferredMultiBulkLength(c,blenp,blen);
+    } else 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"))
diff --git a/src/server.c b/src/server.c
index 484716ab..7a02cb8b 100644
--- a/src/server.c
+++ b/src/server.c
@@ -253,7 +253,7 @@ struct redisCommand redisCommandTable[] = {
     {"persist",persistCommand,2,"wF",0,NULL,1,1,1,0,0},
     {"slaveof",slaveofCommand,3,"ast",0,NULL,0,0,0,0,0},
     {"role",roleCommand,1,"lst",0,NULL,0,0,0,0,0},
-    {"debug",debugCommand,-2,"as",0,NULL,0,0,0,0,0},
+    {"debug",debugCommand,-1,"as",0,NULL,0,0,0,0,0},
     {"config",configCommand,-2,"art",0,NULL,0,0,0,0,0},
     {"subscribe",subscribeCommand,-2,"rpslt",0,NULL,0,0,0,0,0},
     {"unsubscribe",unsubscribeCommand,-1,"rpslt",0,NULL,0,0,0,0,0},