gnutls_global_init/deinit: don't use any locking during constructor

This ensures that there is no deadlock on unexpected errors, such
as missing symbols (e.g., on lazy linking). Reported by Ludovic Courtès.

diff --git a/lib/global.c b/lib/global.c
index 535bb19896f0082bddbb152f4fc9a1a407f85481..d75cea8330ddb62ebfd06ea5bd275537569a9a18 100644 (file)
--- a/lib/global.c
+++ b/lib/global.c
@@ -79,6 +79,9 @@ gnutls_log_func _gnutls_log_func = NULL;
 gnutls_audit_log_func _gnutls_audit_log_func = NULL;
 int _gnutls_log_level = 0;     /* default log level */
 
+static int _gnutls_global_init(unsigned constructor);
+static void _gnutls_global_deinit(unsigned destructor);
+
 static void default_log_func(int level, const char* str)
 {
        fprintf(stderr, "gnutls[%d]: %s", level, str);
@@ -216,12 +219,19 @@ static int _gnutls_init_ret = 0;
  *   otherwise a negative error code is returned.
  **/
 int gnutls_global_init(void)
+{
+       return _gnutls_global_init(0);
+}
+
+static int _gnutls_global_init(unsigned constructor)
 {
        int ret = 0, res;
        int level;
        const char* e;
-       
-       GNUTLS_STATIC_MUTEX_LOCK(global_init_mutex);
+
+       if (!constructor) {
+               GNUTLS_STATIC_MUTEX_LOCK(global_init_mutex);
+       }
 
        _gnutls_init++;
        if (_gnutls_init > 1) {
@@ -379,13 +389,17 @@ int gnutls_global_init(void)
 
       out:
        _gnutls_init_ret = ret;
-       GNUTLS_STATIC_MUTEX_UNLOCK(global_init_mutex);
+       if (!constructor) {
+               GNUTLS_STATIC_MUTEX_UNLOCK(global_init_mutex);
+       }
        return ret;
 }
 
 static void _gnutls_global_deinit(unsigned destructor)
 {
-       GNUTLS_STATIC_MUTEX_LOCK(global_init_mutex);
+       if (!destructor) {
+               GNUTLS_STATIC_MUTEX_LOCK(global_init_mutex);
+       }
 
        if (_gnutls_init == 1) {
                _gnutls_init = 0;
@@ -431,7 +445,9 @@ static void _gnutls_global_deinit(unsigned destructor)
        }
 
  fail:
-       GNUTLS_STATIC_MUTEX_UNLOCK(global_init_mutex);
+       if (!destructor) {
+               GNUTLS_STATIC_MUTEX_UNLOCK(global_init_mutex);
+       }
 }
 
 /**
@@ -485,7 +501,7 @@ const char *e;
                        return;
        }
 
-       ret = gnutls_global_init();
+       ret = _gnutls_global_init(1);
        if (ret < 0) {
                fprintf(stderr, "Error in GnuTLS initialization: %s\n", gnutls_strerror(ret));
                _gnutls_switch_lib_state(LIB_STATE_ERROR);