X-Git-Url: http://git.lttng.org./?a=blobdiff_plain;f=libringbuffer%2Fshm.c;h=563903877f5eb59a62409ce32662a8bd6f7600bd;hb=a88038977008704e88544601cef0291b138f8387;hp=86e8d9184e3c8a3fb066df69e2808028d790fe74;hpb=7a9c21bd702ae4d54d8c1f623e9837e0248b0643;p=lttng-ust.git

diff --git a/libringbuffer/shm.c b/libringbuffer/shm.c
index 86e8d918..56390387 100644
--- a/libringbuffer/shm.c
+++ b/libringbuffer/shm.c
@@ -67,8 +67,18 @@ struct shm_object *shm_object_table_append(struct shm_object_table *table,
 	 * We specifically do _not_ use the / at the beginning of the
 	 * pathname so that some OS implementations can keep it local to
 	 * the process (POSIX leaves this implementation-defined).
+	 * Ignore the shm_unlink errors, because we handle leaks that
+	 * could occur by applications crashing between shm_open and
+	 * shm_unlink by unlinking the shm before every open. Therefore,
+	 * we can only leak one single shm (and only if the application
+	 * crashes between shm_open and the following shm_unlink).
 	 */
 	do {
+		ret = shm_unlink("ust-shm-tmp");
+		if (ret < 0 && errno != ENOENT) {
+			PERROR("shm_unlink");
+			goto error_shm_unlink;
+		}
 		shmfd = shm_open("ust-shm-tmp",
 				 O_CREAT | O_EXCL | O_RDWR, 0700);
 	} while (shmfd < 0 && errno == EEXIST);
@@ -77,9 +87,9 @@ struct shm_object *shm_object_table_append(struct shm_object_table *table,
 		goto error_shm_open;
 	}
 	ret = shm_unlink("ust-shm-tmp");
-	if (ret) {
+	if (ret < 0 && errno != ENOENT) {
 		PERROR("shm_unlink");
-		goto error_unlink;
+		goto error_shm_release;
 	}
 	ret = ftruncate(shmfd, memory_map_size);
 	if (ret) {
@@ -98,18 +108,19 @@ struct shm_object *shm_object_table_append(struct shm_object_table *table,
 	obj->memory_map = memory_map;
 	obj->memory_map_size = memory_map_size;
 	obj->allocated_len = 0;
+	obj->index = table->allocated_len++;
 
-	table->allocated_len++;
 	return obj;
 
 error_mmap:
 error_ftruncate:
-error_unlink:
+error_shm_release:
 	ret = close(shmfd);
 	if (ret) {
 		PERROR("close");
 		assert(0);
 	}
+error_shm_unlink:
 error_shm_open:
 error_fcntl:
 	for (i = 0; i < 2; i++) {
@@ -120,7 +131,6 @@ error_fcntl:
 		}
 	}
 error_pipe:
-	free(obj);
 	return NULL;
 	
 }