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[PATCH] Always do locking when iterating over list of streams (bug 15142)
[BZ #15142]
* libio/genops.c (_IO_list_all_stamp): Delete. All uses removed.
(_IO_flush_all_lockp): Always lock list_all_lock.
(_IO_flush_all_linebuffered): Likewise.
(_IO_unbuffer_all): Likewise.
diff --git a/libio/genops.c b/libio/genops.c
index 6ad7346cae..89376d1b9b 100644
--- a/libio/genops.c
+++ b/libio/genops.c
@@ -38,10 +38,6 @@
static _IO_lock_t list_all_lock = _IO_lock_initializer;
#endif
-/* Used to signal modifications to the list of FILE decriptors. */
-static int _IO_list_all_stamp;
-
-
static _IO_FILE *run_fp;
#ifdef _IO_MTSAFE_IO
@@ -69,16 +65,12 @@ _IO_un_link (struct _IO_FILE_plus *fp)
if (_IO_list_all == NULL)
;
else if (fp == _IO_list_all)
- {
- _IO_list_all = (struct _IO_FILE_plus *) _IO_list_all->file._chain;
- ++_IO_list_all_stamp;
- }
+ _IO_list_all = (struct _IO_FILE_plus *) _IO_list_all->file._chain;
else
for (f = &_IO_list_all->file._chain; *f; f = &(*f)->_chain)
if (*f == (_IO_FILE *) fp)
{
*f = fp->file._chain;
- ++_IO_list_all_stamp;
break;
}
fp->file._flags &= ~_IO_LINKED;
@@ -106,7 +98,6 @@ _IO_link_in (struct _IO_FILE_plus *fp)
#endif
fp->file._chain = (_IO_FILE *) _IO_list_all;
_IO_list_all = fp;
- ++_IO_list_all_stamp;
#ifdef _IO_MTSAFE_IO
_IO_funlockfile ((_IO_FILE *) fp);
run_fp = NULL;
@@ -794,17 +785,13 @@ _IO_flush_all_lockp (int do_lock)
{
int result = 0;
struct _IO_FILE *fp;
- int last_stamp;
#ifdef _IO_MTSAFE_IO
- __libc_cleanup_region_start (do_lock, flush_cleanup, NULL);
- if (do_lock)
- _IO_lock_lock (list_all_lock);
+ _IO_cleanup_region_start_noarg (flush_cleanup);
+ _IO_lock_lock (list_all_lock);
#endif
- last_stamp = _IO_list_all_stamp;
- fp = (_IO_FILE *) _IO_list_all;
- while (fp != NULL)
+ for (fp = (_IO_FILE *) _IO_list_all; fp != NULL; fp = fp->_chain)
{
run_fp = fp;
if (do_lock)
@@ -823,21 +810,11 @@ _IO_flush_all_lockp (int do_lock)
if (do_lock)
_IO_funlockfile (fp);
run_fp = NULL;
-
- if (last_stamp != _IO_list_all_stamp)
- {
- /* Something was added to the list. Start all over again. */
- fp = (_IO_FILE *) _IO_list_all;
- last_stamp = _IO_list_all_stamp;
- }
- else
- fp = fp->_chain;
}
#ifdef _IO_MTSAFE_IO
- if (do_lock)
- _IO_lock_unlock (list_all_lock);
- __libc_cleanup_region_end (0);
+ _IO_lock_unlock (list_all_lock);
+ _IO_cleanup_region_end (0);
#endif
return result;
@@ -856,16 +833,13 @@ void
_IO_flush_all_linebuffered (void)
{
struct _IO_FILE *fp;
- int last_stamp;
#ifdef _IO_MTSAFE_IO
_IO_cleanup_region_start_noarg (flush_cleanup);
_IO_lock_lock (list_all_lock);
#endif
- last_stamp = _IO_list_all_stamp;
- fp = (_IO_FILE *) _IO_list_all;
- while (fp != NULL)
+ for (fp = (_IO_FILE *) _IO_list_all; fp != NULL; fp = fp->_chain)
{
run_fp = fp;
_IO_flockfile (fp);
@@ -875,15 +849,6 @@ _IO_flush_all_linebuffered (void)
_IO_funlockfile (fp);
run_fp = NULL;
-
- if (last_stamp != _IO_list_all_stamp)
- {
- /* Something was added to the list. Start all over again. */
- fp = (_IO_FILE *) _IO_list_all;
- last_stamp = _IO_list_all_stamp;
- }
- else
- fp = fp->_chain;
}
#ifdef _IO_MTSAFE_IO
@@ -919,6 +884,12 @@ static void
_IO_unbuffer_all (void)
{
struct _IO_FILE *fp;
+
+#ifdef _IO_MTSAFE_IO
+ _IO_cleanup_region_start_noarg (flush_cleanup);
+ _IO_lock_lock (list_all_lock);
+#endif
+
for (fp = (_IO_FILE *) _IO_list_all; fp; fp = fp->_chain)
{
if (! (fp->_flags & _IO_UNBUFFERED)
@@ -961,6 +932,11 @@ _IO_unbuffer_all (void)
used. */
fp->_mode = -1;
}
+
+#ifdef _IO_MTSAFE_IO
+ _IO_lock_unlock (list_all_lock);
+ _IO_cleanup_region_end (0);
+#endif
}
--
2.14.1
--
Andreas Schwab, SUSE Labs, schwab@suse.de
GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE 1748 E4D4 88E3 0EEA B9D7
"And now for something completely different."