Use pthread_atfork to lock/unlock yaz_log system

[yaz-moved-to-github.git] / src / log.c

diff --git a/src/log.c b/src/log.c
index 97bc43b..38ecac7 100644 (file)
--- a/src/log.c
+++ b/src/log.c
@@ -1,5 +1,5 @@
 /* This file is part of the YAZ toolkit.
- * Copyright (C) 1995-2013 Index Data
+ * Copyright (C) Index Data
  * See the file LICENSE for details.
  */
 
@@ -30,8 +30,12 @@
 #include <yaz/errno.h>
 #include <yaz/thread_id.h>
 #include <yaz/log.h>
+#include <yaz/mutex.h>
 #include <yaz/snprintf.h>
 #include <yaz/xmalloc.h>
+#if YAZ_POSIX_THREADS
+#include <pthread.h>
+#endif
 
 static int l_level = YLOG_DEFAULT_LEVEL;
 
@@ -99,6 +103,18 @@ static struct {
 
 static unsigned int next_log_bit = YLOG_LAST_BIT<<1; /* first dynamic bit */
 
+static YAZ_MUTEX log_mutex = 0;
+
+static void yaz_log_lock(void)
+{
+    yaz_mutex_enter(log_mutex);
+}
+
+static void yaz_log_unlock(void)
+{
+    yaz_mutex_leave(log_mutex);
+}
+
 static void internal_log_init(void)
 {
     static int mutex_init_flag = 0; /* not yet initialized */
@@ -108,6 +124,11 @@ static void internal_log_init(void)
         return;
     mutex_init_flag = 1; /* here, 'cause nmem_mutex_create may call yaz_log */
 
+    if (log_mutex == 0)
+        yaz_mutex_create(&log_mutex);
+#if YAZ_POSIX_THREADS
+    pthread_atfork(yaz_log_lock, yaz_log_unlock, yaz_log_unlock);
+#endif
     env = getenv("YAZ_LOG");
     if (env)
         l_level = yaz_log_mask_str_x(env, l_level);
@@ -342,12 +363,14 @@ static void yaz_log_do_reopen(const char *filemode)
     struct tm *tm;
 #endif
 
+    yaz_log_lock();
 #if HAVE_LOCALTIME_R
     localtime_r(&cur_time, tm);
 #else
     tm = localtime(&cur_time);
 #endif
     yaz_log_open_check(tm, 1, filemode);
+    yaz_log_unlock();
 }
 
 
@@ -379,6 +402,7 @@ static void yaz_log_to_file(int level, const char *log_message)
 
     internal_log_init();
 
+    yaz_log_lock();
 #if HAVE_LOCALTIME_R
     localtime_r(&ti, tm);
 #else
@@ -436,6 +460,7 @@ static void yaz_log_to_file(int level, const char *log_message)
         if (l_level & YLOG_FLUSH)
             fflush(file);
     }
+    yaz_log_unlock();
 }
 
 void yaz_log(int level, const char *fmt, ...)