Thread-safe xmalloc and xrealloc needs a recursive mutex
The mutex used to protect object access (read_mutex) may need to be
acquired recursively. Introduce init_recursive_mutex() helper function
in thread-utils.c that constructs a mutex with the PHREAD_MUTEX_RECURSIVE
attribute.
pthread_mutex_init() emulation on Win32 is already recursive as it is
implemented on top of the CRITICAL_SECTION type, which is recursive.
http://msdn.microsoft.com/en-us/library/ms682530%28VS.85%29.aspx
Add do-nothing compatibility wrappers for pthread_mutexattr* functions.
Initial-version-by: Fredrik Kuivinen <frekui@gmail.com>
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/thread-utils.c b/thread-utils.c
index 4f9c829..589f838 100644
--- a/thread-utils.c
+++ b/thread-utils.c
@@ -1,4 +1,5 @@
#include "cache.h"
+#include <pthread.h>
#if defined(hpux) || defined(__hpux) || defined(_hpux)
# include <sys/pstat.h>
@@ -43,3 +44,18 @@
return 1;
}
+
+int init_recursive_mutex(pthread_mutex_t *m)
+{
+ pthread_mutexattr_t a;
+ int ret;
+
+ ret = pthread_mutexattr_init(&a);
+ if (!ret) {
+ ret = pthread_mutexattr_settype(&a, PTHREAD_MUTEX_RECURSIVE);
+ if (!ret)
+ ret = pthread_mutex_init(m, &a);
+ pthread_mutexattr_destroy(&a);
+ }
+ return ret;
+}
