backport some mutex initialization and linked list handling fixes from trunk

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.2@29732 65c4cc65-6c06-0410-ace0-fbb531ad65f3

apps/app_sql_postgres.c

@@ -132,7 +132,7 @@ struct ast_PGSQL_id {
 	AST_LIST_ENTRY(ast_PGSQL_id) entries;
 } *ast_PGSQL_id;
 
-AST_LIST_HEAD(PGSQLidshead,ast_PGSQL_id) PGSQLidshead;
+static AST_LIST_HEAD_STATIC(PGSQLidshead,ast_PGSQL_id);
 
 static void *find_identifier(int identifier,int identifier_type) {
 	struct PGSQLidshead *headp;
@@ -551,11 +551,6 @@ int unload_module(void)
 
 int load_module(void)
 {
-	struct PGSQLidshead *headp;
-	
-        headp=&PGSQLidshead;
-        
-	AST_LIST_HEAD_INIT(headp);
 	return ast_register_application(app, PGSQL_exec, synopsis, descrip);
 }
 

dnsmgr.c

@@ -57,7 +57,7 @@ struct ast_dnsmgr_entry {
 	char name[1];
 };
 
-static AST_LIST_HEAD(entry_list, ast_dnsmgr_entry) entry_list;
+static AST_LIST_HEAD_STATIC(entry_list, ast_dnsmgr_entry);
 
 AST_MUTEX_DEFINE_STATIC(refresh_lock);
 
@@ -289,7 +289,6 @@ int dnsmgr_init(void)
 		ast_log(LOG_ERROR, "Unable to create schedule context.\n");
 		return -1;
 	}
-	AST_LIST_HEAD_INIT(&entry_list);
 	ast_cli_register(&cli_reload);
 	ast_cli_register(&cli_status);
 	return do_reload(1);

include/asterisk/linkedlists.h

@@ -100,6 +100,23 @@ struct name {								\
 	struct type *last;						\
 }
 
+/*!
+  \brief Defines initial values for a declaration of AST_LIST_HEAD
+*/
+#define AST_LIST_HEAD_INIT_VALUE	{		\
+	.first = NULL,					\
+	.last = NULL,					\
+	.lock = AST_MUTEX_INIT_VALUE,			\
+	}
+
+/*!
+  \brief Defines initial values for a declaration of AST_LIST_HEAD_NOLOCK
+*/
+#define AST_LIST_HEAD_NOLOCK_INIT_VALUE	{	\
+	.first = NULL,					\
+	.last = NULL,					\
+	}
+
 /*!
   \brief Defines a structure to be used to hold a list of specified type, statically initialized.
   \param name This will be the name of the defined structure.
@@ -122,11 +139,18 @@ struct name {								\
 	struct type *first;						\
 	struct type *last;						\
 	ast_mutex_t lock;						\
-} name = {								\
-	.first = NULL,							\
-	.last = NULL,							\
-	.lock = AST_MUTEX_INIT_VALUE,					\
-};
+} name = AST_LIST_HEAD_INIT_VALUE
+
+/*!
+  \brief Defines a structure to be used to hold a list of specified type, statically initialized.
+
+  This is the same as AST_LIST_HEAD_STATIC, except without the lock included.
+*/
+#define AST_LIST_HEAD_NOLOCK_STATIC(name, type)				\
+struct name {								\
+	struct type *first;						\
+	struct type *last;						\
+} name = AST_LIST_HEAD_NOLOCK_INIT_VALUE
 
 /*!
   \brief Initializes a list head structure with a specified first entry.
@@ -183,6 +207,12 @@ struct {								\
  */
 #define	AST_LIST_FIRST(head)	((head)->first)
 
+/*!
+  \brief Returns the last entry contained in a list.
+  \param head This is a pointer to the list tail structure
+ */
+#define	AST_LIST_LAST(head)	((head)->last)
+
 /*!
   \brief Returns the next entry in the list after the given entry.
   \param elm This is a pointer to the current entry.
@@ -433,11 +463,13 @@ struct {								\
 			(head)->last = NULL;			\
 	} else {								\
 		typeof(elm) curelm = (head)->first;			\
-		while (curelm->field.next != (elm))			\
+		while (curelm && (curelm->field.next != (elm)))			\
 			curelm = curelm->field.next;			\
-		curelm->field.next = (elm)->field.next;			\
-		if ((head)->last == (elm))				\
-			(head)->last = curelm;				\
+		if (curelm) { \
+			curelm->field.next = (elm)->field.next;			\
+			if ((head)->last == (elm))				\
+				(head)->last = curelm;				\
+		} \
 	}								\
         (elm)->field.next = NULL;                                       \
 } while (0)

include/asterisk/lock.h

@@ -97,6 +97,13 @@ typedef struct ast_mutex_info ast_mutex_t;
 
 typedef pthread_cond_t ast_cond_t;
 
+static pthread_mutex_t empty_mutex;
+
+static void __attribute__((constructor)) init_empty_mutex(void)
+{
+	memset(&empty_mutex, 0, sizeof(empty_mutex));
+}
+
 static inline int __ast_pthread_mutex_init_attr(const char *filename, int lineno, const char *func,
 						const char *mutex_name, ast_mutex_t *t,
 						pthread_mutexattr_t *attr) 
@@ -105,14 +112,16 @@ static inline int __ast_pthread_mutex_init_attr(const char *filename, int lineno
 	int canlog = strcmp(filename, "logger.c");
 
 	if ((t->mutex) != ((pthread_mutex_t) PTHREAD_MUTEX_INITIALIZER)) {
-		__ast_mutex_logger("%s line %d (%s): Error: mutex '%s' is already initialized.\n",
-				   filename, lineno, func, mutex_name);
-		__ast_mutex_logger("%s line %d (%s): Error: previously initialization of mutex '%s'.\n",
-				   t->file, t->lineno, t->func, mutex_name);
+		if ((t->mutex) != (empty_mutex)) {
+			__ast_mutex_logger("%s line %d (%s): Error: mutex '%s' is already initialized.\n",
+					   filename, lineno, func, mutex_name);
+			__ast_mutex_logger("%s line %d (%s): Error: previously initialization of mutex '%s'.\n",
+					   t->file, t->lineno, t->func, mutex_name);
 #ifdef THREAD_CRASH
-		DO_THREAD_CRASH;
+			DO_THREAD_CRASH;
 #endif
-		return 0;
+			return 0;
+		}
 	}
 #endif
 

pbx.c

@@ -3706,6 +3706,7 @@ void ast_merge_contexts_and_delete(struct ast_context **extcontexts, const char
 	int length;
 	struct ast_state_cb *thiscb, *prevcb;
 
+	memset(&store, 0, sizeof(store));
 	AST_LIST_HEAD_INIT(&store);
 
 	/* it is very important that this function hold the hintlock _and_ the conlock

res/res_features.c

@@ -866,7 +866,7 @@ struct ast_call_feature builtin_features[] =
 };
 
 
-static AST_LIST_HEAD(feature_list,ast_call_feature) feature_list;
+static AST_LIST_HEAD_STATIC(feature_list,ast_call_feature);
 
 /* register new feature into feature_list*/
 void ast_register_feature(struct ast_call_feature *feature)
@@ -2145,7 +2145,6 @@ int load_module(void)
 {
 	int res;
 	
-	AST_LIST_HEAD_INIT(&feature_list);
 	memset(parking_ext, 0, sizeof(parking_ext));
 	memset(parking_con, 0, sizeof(parking_con));