X-Git-Url: http://git.tuebingen.mpg.de/?p=dss.git;a=blobdiff_plain;f=ipc.c;h=c55554c5d3fd815cd09c045a94f7b72d5bd5db85;hp=78533bee310a6f7b9b46cf811fb12623dc2f775e;hb=5235e61583d358c177955c1da642e7c49e527acc;hpb=66cdd5bc99a53d2b408a6cdc2d501fe27f9db13b

diff --git a/ipc.c b/ipc.c
index 78533be..c55554c 100644
--- a/ipc.c
+++ b/ipc.c
@@ -13,12 +13,13 @@
 #include <stddef.h>
 #include <limits.h>
 #include <sys/param.h>
+#include <stdbool.h>
 
 #include "gcc-compat.h"
-#include "string.h"
+#include "str.h"
 #include "log.h"
 #include "gcc-compat.h"
-#include "error.h"
+#include "err.h"
 #include "ipc.h"
 
 #if (defined(__GNUC__) && defined(__i386__))
@@ -227,7 +228,7 @@ error:
 	return ret;
 }
 
-static inline int get_key_or_die(char *config_file)
+static int get_key_or_die(const char *config_file)
 {
 	int ret;
 	struct stat statbuf;
@@ -284,7 +285,6 @@ static int do_semop(int id, struct sembuf *sops, int num)
 static int mutex_lock(int id)
 {
 	struct sembuf sops[4];
-	int ret;
 
 	DSS_DEBUG_LOG(("locking\n"));
 
@@ -304,31 +304,24 @@ static int mutex_lock(int id)
 	sops[3].sem_op = 1;
 	sops[3].sem_flg = SEM_UNDO | IPC_NOWAIT;
 
-	ret = do_semop(id, sops, 4);
-	if (ret < 0)
-		return -ERRNO_TO_DSS_ERROR(errno);
-	return 1;
+	return do_semop(id, sops, 4);
 }
 
-static int mutex_try_lock(int id)
+static bool mutex_is_locked(int id)
 {
-	struct sembuf sops[2];
+	struct sembuf sops;
 	int ret;
 
 	DSS_DEBUG_LOG(("trying to lock\n"));
 
-	sops[0].sem_num = 0;
-	sops[0].sem_op = 0;
-	sops[0].sem_flg = SEM_UNDO | IPC_NOWAIT;
+	sops.sem_num = 0;
+	sops.sem_op = 0;
+	sops.sem_flg = SEM_UNDO | IPC_NOWAIT;
 
-	sops[1].sem_num = 0;
-	sops[1].sem_op = 1;
-	sops[1].sem_flg = SEM_UNDO | IPC_NOWAIT;
-
-	ret = do_semop(id, sops, 2);
+	ret = do_semop(id, &sops, 1);
 	if (ret < 0)
-		return -ERRNO_TO_DSS_ERROR(errno);
-	return 1;
+		return true;
+	return false;
 }
 
 int lock_dss(char *config_file)
@@ -345,6 +338,8 @@ int get_dss_pid(char *config_file, pid_t *pid)
 {
 	int ret, semid, key = get_key_or_die(config_file);
 
+	if (pid)
+		*pid = 0;
 	ret = mutex_get(key, 0);
 	if (ret < 0)
 		return ret;
@@ -352,9 +347,7 @@ int get_dss_pid(char *config_file, pid_t *pid)
 	ret = semctl(semid, 1, GETPID);
 	if (ret < 0)
 		return -E_NOT_RUNNING;
-	*pid = ret;
-	ret = mutex_try_lock(semid);
-	if (ret >= 0)
-		return -E_NOT_RUNNING;
-	return 1;
+	if (pid)
+		*pid = ret;
+	return mutex_is_locked(semid)? 1 : -E_NOT_RUNNING;
 }