[Cluster-devel] [PATCH] cman: allow late close of stderr file descriptor and free resources

[Fabio M. Di Nitto]

In case debug is enabled, and cman is executed via init script, we leak
a fd associated to a file that will grow indefinetely in size.

We address this situation by adding a very specific cman_tool startup
option associated to init script, to tell cman to perform a late
close of stderr and freeing correctly all resources.

Resolves: rhbz#740385

Signed-off-by: Fabio M. Di Nitto <fdinitto at redhat.com>
---
 cman/cman_tool/cman_tool.h |    1 +
 cman/cman_tool/join.c      |    4 ++++
 cman/cman_tool/main.c      |    7 ++++++-
 cman/daemon/ais.c          |   11 +++++++++++
 cman/init.d/cman.in        |    2 +-
 5 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/cman/cman_tool/cman_tool.h b/cman/cman_tool/cman_tool.h
index e84b491..e1250ee 100644
--- a/cman/cman_tool/cman_tool.h
+++ b/cman/cman_tool/cman_tool.h
@@ -84,6 +84,7 @@ struct commandline
 	int remove;
 	int force;
         int verbose;
+	int nostderr_debug;
         int nodeid;
 	int timeout;
 	unsigned int config_version;
diff --git a/cman/cman_tool/join.c b/cman/cman_tool/join.c
index caa5bf6..a33c8b4 100644
--- a/cman/cman_tool/join.c
+++ b/cman/cman_tool/join.c
@@ -186,6 +186,10 @@ int join(commandline_t *comline, char *main_envp[])
 		snprintf(scratch, sizeof(scratch), "CMAN_DEBUG=%d", comline->verbose);
 		envp[envptr++] = strdup(scratch);
 	}
+	if (comline->nostderr_debug) {
+		snprintf(scratch, sizeof(scratch), "CMAN_NOSTDERR_DEBUG=true");
+		envp[envptr++] = strdup(scratch);
+	}
 	if (comline->noconfig_opt) {
 		envp[envptr++] = strdup("CMAN_NOCONFIG=true");
 		snprintf(config_modules, sizeof(config_modules), "cmanpreconfig%s",
diff --git a/cman/cman_tool/main.c b/cman/cman_tool/main.c
index 61d29aa..88612c4 100644
--- a/cman/cman_tool/main.c
+++ b/cman/cman_tool/main.c
@@ -12,7 +12,7 @@
 
 #define DEFAULT_CONFIG_MODULE "xmlconfig"
 
-#define OPTION_STRING		("m:n:v:e:2p:c:i:N:t:o:k:F:C:VAPwfqah?XD::Sd::r::")
+#define OPTION_STRING		("m:n:v:e:2p:c:i:N:t:o:k:F:C:VAPwfqazh?XD::Sd::r::")
 #define OP_JOIN			1
 #define OP_LEAVE		2
 #define OP_EXPECTED		3
@@ -62,6 +62,7 @@ static void print_usage(int subcmd)
 		printf("  -D<fail|warn|none> What to do about the config. Default (without -D) is to\n");
 		printf("                   validate the config. with -D no validation will be done.\n");
 		printf("                   -Dwarn will print errors but allow the operation to continue.\n");
+		printf("  -z		   Disable stderr debugging output.\n");
 		printf("\n");
 	}
 
@@ -1047,6 +1048,10 @@ static void decode_arguments(int argc, char *argv[], commandline_t *comline)
 				comline->verbose = 255;
 			break;
 
+		case 'z':
+			comline->nostderr_debug = 1;
+			break;
+
 		case 'w':
 			comline->wait_opt = TRUE;
 			break;
diff --git a/cman/daemon/ais.c b/cman/daemon/ais.c
index 05cb8d7..6b5640a 100644
--- a/cman/daemon/ais.c
+++ b/cman/daemon/ais.c
@@ -14,6 +14,8 @@
 #include <arpa/inet.h>
 #include <netdb.h>
 #include <inttypes.h>
+#include <sys/stat.h>
+#include <fcntl.h>
 
 /* corosync headers */
 #include <corosync/corotypes.h>
@@ -220,6 +222,15 @@ static int cman_exec_init_fn(struct corosync_api_v1 *api)
 	api->tpg_init(&group_handle, cman_deliver_fn, cman_confchg_fn);
 	api->tpg_join(group_handle, cman_group, 1);
 
+	if (getenv("CMAN_NOSTDERR_DEBUG")) {
+		int tmpfd;
+		tmpfd = open("/dev/null", O_RDWR);
+		if (tmpfd > -1 && tmpfd != STDERR_FILENO) {
+			dup2(tmpfd, STDERR_FILENO);
+			close(tmpfd);
+		}
+	}
+
 	return 0;
 }
 
diff --git a/cman/init.d/cman.in b/cman/init.d/cman.in
index fecefea..d0c6f70 100644
--- a/cman/init.d/cman.in
+++ b/cman/init.d/cman.in
@@ -556,7 +556,7 @@ start_cman()
 		return 1
 	fi
 
-	cman_tool -t $CMAN_CLUSTER_TIMEOUT -w join $cman_join_opts > $tmpfile 2>&1 &
+	cman_tool -z -t $CMAN_CLUSTER_TIMEOUT -w join $cman_join_opts > $tmpfile 2>&1 &
 
 	while status cman_tool >/dev/null 2>&1; do
 		sleep 0.2
-- 
1.7.4.4