Libc-1439.100.3.tar.gz

[apple/libc.git] / stdio / FreeBSD / _flock_stub.c

diff --git a/stdio/FreeBSD/_flock_stub.c b/stdio/FreeBSD/_flock_stub.c
index 3a73ee1a68257d9eeecf8215eb4ef95c61ee1555..330830f9e8d7c0a87407be55cfcae9df47c59176 100644 (file)
--- a/stdio/FreeBSD/_flock_stub.c
+++ b/stdio/FreeBSD/_flock_stub.c
@@ -10,10 +10,7 @@
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
- * 3. All advertising materials mentioning features or use of this software
- *    must display the following acknowledgement:
- *     This product includes software developed by John Birrell.
- * 4. Neither the name of the author nor the names of any co-contributors
+ * 3. Neither the name of the author nor the names of any co-contributors
  *    may be used to endorse or promote products derived from this software
  *    without specific prior written permission.
  *
@@ -38,9 +35,10 @@
  */
 
 #include <sys/cdefs.h>
-__FBSDID("$FreeBSD: src/lib/libc/stdio/_flock_stub.c,v 1.14 2004/03/09 04:51:58 jb Exp $");
+__FBSDID("$FreeBSD: src/lib/libc/stdio/_flock_stub.c,v 1.16 2008/04/17 22:17:53 jhb Exp $");
 
 #include "namespace.h"
+#include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -49,7 +47,6 @@ __FBSDID("$FreeBSD: src/lib/libc/stdio/_flock_stub.c,v 1.14 2004/03/09 04:51:58
 
 #include "local.h"
 
-
 /*
  * Weak symbols for externally visible functions in this file:
  */
@@ -58,32 +55,13 @@ __weak_reference(_flockfile_debug_stub, _flockfile_debug);
 __weak_reference(_ftrylockfile, ftrylockfile);
 __weak_reference(_funlockfile, funlockfile);
 
-/*
- * We need to retain binary compatibility for a while.  So pretend
- * that _lock is part of FILE * even though it is dereferenced off
- * _extra now.  When we stop encoding the size of FILE into binaries
- * this can be changed in stdio.h.  This will reduce the amount of
- * code that has to change in the future (just remove this comment
- * and #define).
- */
-#define _lock _extra
-
 void
 _flockfile(FILE *fp)
 {
-       pthread_t curthread = _pthread_self();
-
-       if (fp->_lock->fl_owner == curthread)
-               fp->_lock->fl_count++;
-       else {
-               /*
-                * Make sure this mutex is treated as a private
-                * internal mutex:
-                */
-               _pthread_mutex_lock(&fp->_lock->fl_mutex);
-               fp->_lock->fl_owner = curthread;
-               fp->_lock->fl_count = 1;
-       }
+       // <rdar://problem/21533199> - preserve errno.
+       int save_errno = errno;
+       _pthread_mutex_lock(&fp->_fl_mutex);
+       errno = save_errno;
 }
 
 /*
@@ -98,52 +76,22 @@ _flockfile_debug_stub(FILE *fp, char *fname, int lineno)
 int
 _ftrylockfile(FILE *fp)
 {
-       pthread_t curthread = _pthread_self();
        int     ret = 0;
 
-       if (fp->_lock->fl_owner == curthread)
-               fp->_lock->fl_count++;
-       /*
-        * Make sure this mutex is treated as a private
-        * internal mutex:
-        */
-       else if (_pthread_mutex_trylock(&fp->_lock->fl_mutex) == 0) {
-               fp->_lock->fl_owner = curthread;
-               fp->_lock->fl_count = 1;
-       }
-       else
+       // <rdar://problem/21533199> - preserve errno.
+       int save_errno = errno;
+       if (_pthread_mutex_trylock(&fp->_fl_mutex) != 0)
                ret = -1;
+       errno = save_errno;
+
        return (ret);
 }
 
 void 
 _funlockfile(FILE *fp)
 {
-       pthread_t       curthread = _pthread_self();
-
-       /*
-        * Check if this file is owned by the current thread:
-        */
-       if (fp->_lock->fl_owner == curthread) {
-               /*
-                * Check if this thread has locked the FILE
-                * more than once:
-                */
-               if (fp->_lock->fl_count > 1)
-                       /*
-                        * Decrement the count of the number of
-                        * times the running thread has locked this
-                        * file:
-                        */
-                       fp->_lock->fl_count--;
-               else {
-                       /*
-                        * The running thread will release the
-                        * lock now:
-                        */
-                       fp->_lock->fl_count = 0;
-                       fp->_lock->fl_owner = NULL;
-                       _pthread_mutex_unlock(&fp->_lock->fl_mutex);
-               }
-       }
+       // <rdar://problem/21533199> - preserve errno.
+       int save_errno = errno;
+       _pthread_mutex_unlock(&fp->_fl_mutex);
+       errno = save_errno;
 }