[tor-commits] [tor/master] Specialize handling for mutexes allocated for condition variables

[nickm at torproject.org]

commit 6c9363310aaea9d39fae4d9dd50e78d42c3598b3
Author: Nick Mathewson <nickm at torproject.org>
Date:   Tue Sep 24 15:03:51 2013 -0400

    Specialize handling for mutexes allocated for condition variables
    
    (These must not be reentrant mutexes with pthreads.)
---
 src/common/compat_pthreads.c   |   16 ++++++++++++++++
 src/common/compat_threads.h    |    1 +
 src/common/compat_winthreads.c |    6 ++++++
 3 files changed, 23 insertions(+)

diff --git a/src/common/compat_pthreads.c b/src/common/compat_pthreads.c
index e58b3f7..59b54a6 100644
--- a/src/common/compat_pthreads.c
+++ b/src/common/compat_pthreads.c
@@ -96,6 +96,22 @@ tor_mutex_init(tor_mutex_t *mutex)
     tor_fragile_assert();
   }
 }
+
+/** As tor_mutex_init, but initialize a mutex suitable for use with a
+ * condition variable. */
+void
+tor_mutex_init_for_cond(tor_mutex_t *mutex)
+{
+  int err;
+  if (PREDICT_UNLIKELY(!threads_initialized))
+    tor_threads_init();
+  err = pthread_mutex_init(&mutex->mutex, NULL);
+  if (PREDICT_UNLIKELY(err)) {
+    log_err(LD_GENERAL, "Error %d creating a mutex.", err);
+    tor_fragile_assert();
+  }
+}
+
 /** Wait until <b>m</b> is free, then acquire it. */
 void
 tor_mutex_acquire(tor_mutex_t *m)
diff --git a/src/common/compat_threads.h b/src/common/compat_threads.h
index 6d3ba3a..581d8dd 100644
--- a/src/common/compat_threads.h
+++ b/src/common/compat_threads.h
@@ -47,6 +47,7 @@ typedef struct tor_mutex_t {
 
 tor_mutex_t *tor_mutex_new(void);
 void tor_mutex_init(tor_mutex_t *m);
+void tor_mutex_init_for_cond(tor_mutex_t *m);
 void tor_mutex_acquire(tor_mutex_t *m);
 void tor_mutex_release(tor_mutex_t *m);
 void tor_mutex_free(tor_mutex_t *m);
diff --git a/src/common/compat_winthreads.c b/src/common/compat_winthreads.c
index 11f91c6..2b1527a 100644
--- a/src/common/compat_winthreads.c
+++ b/src/common/compat_winthreads.c
@@ -49,6 +49,12 @@ tor_mutex_init(tor_mutex_t *m)
   InitializeCriticalSection(&m->mutex);
 }
 void
+tor_mutex_init_for_cond(tor_mutex_t *m)
+{
+  InitializeCriticalSection(&m->mutex);
+}
+
+void
 tor_mutex_uninit(tor_mutex_t *m)
 {
   DeleteCriticalSection(&m->mutex);