From 4dc69497f509956d298455492fe5ab98a9738cb6 Mon Sep 17 00:00:00 2001
From: antirez <antirez@gmail.com>
Date: Mon, 21 Jan 2019 11:28:44 +0100
Subject: [PATCH] Refactoring: always kill AOF/RDB child via helper functions.

---
 src/aof.c         |  2 +-
 src/db.c          |  7 +------
 src/rdb.c         | 10 ++++++++++
 src/replication.c |  5 +----
 src/server.c      |  5 ++---
 src/server.h      |  2 ++
 6 files changed, 17 insertions(+), 14 deletions(-)

diff --git a/src/aof.c b/src/aof.c
index 9497813b2..46ae58324 100644
--- a/src/aof.c
+++ b/src/aof.c
@@ -204,7 +204,7 @@ void aof_background_fsync(int fd) {
 }
 
 /* Kills an AOFRW child process if exists */
-static void killAppendOnlyChild(void) {
+void killAppendOnlyChild(void) {
     int statloc;
     /* No AOFRW child? return. */
     if (server.aof_child_pid == -1) return;
diff --git a/src/db.c b/src/db.c
index 6e7b46ac5..f59ae8406 100644
--- a/src/db.c
+++ b/src/db.c
@@ -448,12 +448,7 @@ void flushallCommand(client *c) {
     signalFlushedDb(-1);
     server.dirty += emptyDb(-1,flags,NULL);
     addReply(c,shared.ok);
-    if (server.rdb_child_pid != -1) {
-        kill(server.rdb_child_pid,SIGUSR1);
-        rdbRemoveTempFile(server.rdb_child_pid);
-        closeChildInfoPipe();
-        updateDictResizePolicy();
-    }
+    if (server.rdb_child_pid != -1) killRDBChild();
     if (server.saveparamslen > 0) {
         /* Normally rdbSave() will reset dirty, but we don't want this here
          * as otherwise FLUSHALL will not be replicated nor put into the AOF. */
diff --git a/src/rdb.c b/src/rdb.c
index 47555101e..351b90774 100644
--- a/src/rdb.c
+++ b/src/rdb.c
@@ -2225,6 +2225,16 @@ void backgroundSaveDoneHandler(int exitcode, int bysignal) {
     }
 }
 
+/* Kill the RDB saving child using SIGUSR1 (so that the parent will know
+ * the child did not exit for an error, but because we wanted), and performs
+ * the cleanup needed. */
+void killRDBChild(void) {
+    kill(server.rdb_child_pid,SIGUSR1);
+    rdbRemoveTempFile(server.rdb_child_pid);
+    closeChildInfoPipe();
+    updateDictResizePolicy();
+}
+
 /* Spawn an RDB child that writes the RDB to the sockets of the slaves
  * that are currently in SLAVE_STATE_WAIT_BGSAVE_START state. */
 int rdbSaveToSlavesSockets(rdbSaveInfo *rsi) {
diff --git a/src/replication.c b/src/replication.c
index a10b10133..a34257546 100644
--- a/src/replication.c
+++ b/src/replication.c
@@ -1254,10 +1254,7 @@ void readSyncBulkPayload(aeEventLoop *el, int fd, void *privdata, int mask) {
                 "Killing process %ld and removing its temp file to avoid "
                 "any race",
                     (long) server.rdb_child_pid);
-            kill(server.rdb_child_pid,SIGUSR1);
-            rdbRemoveTempFile(server.rdb_child_pid);
-            closeChildInfoPipe();
-            updateDictResizePolicy();
+            killRDBChild();
         }
 
         if (rename(server.repl_transfer_tmpfile,server.rdb_filename) == -1) {
diff --git a/src/server.c b/src/server.c
index 41d6f454c..fd4d9adb8 100644
--- a/src/server.c
+++ b/src/server.c
@@ -2798,8 +2798,7 @@ int prepareForShutdown(int flags) {
        overwrite the synchronous saving did by SHUTDOWN. */
     if (server.rdb_child_pid != -1) {
         serverLog(LL_WARNING,"There is a child saving an .rdb. Killing it!");
-        kill(server.rdb_child_pid,SIGUSR1);
-        rdbRemoveTempFile(server.rdb_child_pid);
+        killRDBChild();
     }
 
     if (server.aof_state != AOF_OFF) {
@@ -2814,7 +2813,7 @@ int prepareForShutdown(int flags) {
             }
             serverLog(LL_WARNING,
                 "There is a child rewriting the AOF. Killing it!");
-            kill(server.aof_child_pid,SIGUSR1);
+            killAppendOnlyChild();
         }
         /* Append only file: flush buffers and fsync() the AOF at exit */
         serverLog(LL_NOTICE,"Calling fsync() on the AOF file.");
diff --git a/src/server.h b/src/server.h
index 956494aa3..9e129b62c 100644
--- a/src/server.h
+++ b/src/server.h
@@ -1674,6 +1674,7 @@ int writeCommandsDeniedByDiskError(void);
 /* RDB persistence */
 #include "rdb.h"
 int rdbSaveRio(rio *rdb, int *error, int flags, rdbSaveInfo *rsi);
+void killRDBChild(void);
 
 /* AOF persistence */
 void flushAppendOnlyFile(int force);
@@ -1687,6 +1688,7 @@ void backgroundRewriteDoneHandler(int exitcode, int bysignal);
 void aofRewriteBufferReset(void);
 unsigned long aofRewriteBufferSize(void);
 ssize_t aofReadDiffFromParent(void);
+void killAppendOnlyChild(void);
 
 /* Child info */
 void openChildInfoPipe(void);