From b7b508c76553448dcbf33d8779f4285d8948df64 Mon Sep 17 00:00:00 2001
From: Martin Schwenke <martin@meltin.net>
Date: Fri, 6 Mar 2015 14:05:23 +1100
Subject: [PATCH] ctdb-daemon: Use statically allocated arrays for helper paths

The use of talloc with a static variable is somewhat confusing.
Statically allocate an array and use ctdb_set_helper() instead.

Signed-off-by: Martin Schwenke <martin@meltin.net>
Reviewed-by: Volker Lendecke <vl@samba.org>
---
 ctdb/server/ctdb_lock.c   | 37 +++++++++++++------------------------
 ctdb/server/eventscript.c | 15 ++++++---------
 2 files changed, 19 insertions(+), 33 deletions(-)

diff --git a/ctdb/server/ctdb_lock.c b/ctdb/server/ctdb_lock.c
index c5a2b98bfe8..f5928343df4 100644
--- a/ctdb/server/ctdb_lock.c
+++ b/ctdb/server/ctdb_lock.c
@@ -482,7 +482,7 @@ static void ctdb_lock_timeout_handler(struct tevent_context *ev,
 				    struct timeval current_time,
 				    void *private_data)
 {
-	static const char * debug_locks = NULL;
+	static char debug_locks[PATH_MAX+1] = "";
 	struct lock_context *lock_ctx;
 	struct ctdb_context *ctdb;
 	pid_t pid;
@@ -510,16 +510,10 @@ static void ctdb_lock_timeout_handler(struct tevent_context *ev,
 		       elapsed_time));
 	}
 
-	/* Fire a child process to find the blocking process. */
-	if (debug_locks == NULL) {
-		debug_locks = getenv("CTDB_DEBUG_LOCKS");
-		if (debug_locks == NULL) {
-			debug_locks = talloc_asprintf(ctdb,
-						      "%s/debug_locks.sh",
-						      getenv("CTDB_BASE"));
-		}
-	}
-	if (debug_locks != NULL) {
+	if (ctdb_set_helper("lock debugging helper",
+			    debug_locks, sizeof(debug_locks),
+			    "CTDB_DEBUG_LOCKS",
+			    getenv("CTDB_BASE"), "debug_locks.sh")) {
 		pid = vfork();
 		if (pid == 0) {
 			execl(debug_locks, debug_locks, NULL);
@@ -529,7 +523,7 @@ static void ctdb_lock_timeout_handler(struct tevent_context *ev,
 	} else {
 		DEBUG(DEBUG_WARNING,
 		      (__location__
-		       " Unable to setup lock debugging - no memory?\n"));
+		       " Unable to setup lock debugging\n"));
 	}
 
 	/* Back-off logging if lock is not obtained for a long time */
@@ -754,20 +748,15 @@ static void ctdb_lock_schedule(struct ctdb_context *ctdb)
 	struct lock_context *lock_ctx;
 	int ret, argc;
 	TALLOC_CTX *tmp_ctx;
-	const char *helper = CTDB_HELPER_BINDIR "/ctdb_lock_helper";
-	static const char *prog = NULL;
+	static char prog[PATH_MAX+1] = "";
 	const char **args;
 
-	if (prog == NULL) {
-		const char *t;
-
-		t = getenv("CTDB_LOCK_HELPER");
-		if (t != NULL) {
-			prog = talloc_strdup(ctdb, t);
-		} else {
-			prog = talloc_strdup(ctdb, helper);
-		}
-		CTDB_NO_MEMORY_VOID(ctdb, prog);
+	if (!ctdb_set_helper("lock helper",
+			     prog, sizeof(prog),
+			     "CTDB_LOCK_HELPER",
+			     CTDB_HELPER_BINDIR, "ctdb_lock_helper")) {
+		ctdb_die(ctdb, __location__
+			 " Unable to set lock helper\n");
 	}
 
 	/* Find a lock context with requests */
diff --git a/ctdb/server/eventscript.c b/ctdb/server/eventscript.c
index eaa6a20d31a..d77612150c3 100644
--- a/ctdb/server/eventscript.c
+++ b/ctdb/server/eventscript.c
@@ -261,7 +261,7 @@ failed:
 static void ctdb_event_script_handler(struct event_context *ev, struct fd_event *fde,
 				      uint16_t flags, void *p);
 
-static const char *helper_prog = NULL;
+static char helper_prog[PATH_MAX+1] = "";
 
 static int fork_child_for_script(struct ctdb_context *ctdb,
 				 struct ctdb_event_script_state *state)
@@ -271,15 +271,12 @@ static int fork_child_for_script(struct ctdb_context *ctdb,
 	struct ctdb_script_wire *current = get_current_script(state);
 	int argc;
 	const char **argv;
-	static const char *helper = CTDB_HELPER_BINDIR "/ctdb_event_helper";
 
-	if (helper_prog == NULL) {
-		const char *t = getenv("CTDB_EVENT_HELPER");
-		if (t != NULL) {
-			helper_prog = t;
-		} else {
-			helper_prog = helper;
-		}
+	if (!ctdb_set_helper("event helper", helper_prog, sizeof(helper_prog),
+			     "CTDB_EVENT_HELPER",
+			     CTDB_HELPER_BINDIR, "ctdb_event_helper")) {
+		ctdb_die(ctdb, __location__
+			 " Unable to set event helper\n");
 	}
 
 	current->start = timeval_current();