d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Preserve application code's errno in rtld locking code, it attemps to keep

Browse Source 
any case safe.
This commit is contained in:
David Xu 2008-03-20 09:35:44 +00:00
parent 42b5d159f2
commit 8c38215f50
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=177445
1 changed files with 31 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

33
lib/libthr/thread/thr_rtld.c
View File

@ -36,6 +36,9 @@
#include "rtld_lock.h"
#include "thr_private.h"
#undef errno
extern int errno;
#define CACHE_LINE_SIZE 64
#define WAFLAG 0x1
#define RC_INCR 0x2
@ -88,20 +91,38 @@ _thr_rtld_lock_destroy(void *lock)
free(l->base);
}
#define SAVE_ERRNO() { \
if (curthread != _thr_initial) \
errsave = curthread->error; \
else \
errsave = errno; \
}
#define RESTORE_ERRNO() { \
if (curthread != _thr_initial) \
curthread->error = errsave; \
else \
errno = errsave; \
}
static void
_thr_rtld_rlock_acquire(void *lock)
{
struct pthread *curthread;
struct rtld_lock *l;
long v;
int errsave;
curthread = _get_curthread();
SAVE_ERRNO();
l = (struct rtld_lock *)lock;
THR_CRITICAL_ENTER(curthread);
atomic_add_acq_int(&l->lock, RC_INCR);
if (!(l->lock & WAFLAG))
if (!(l->lock & WAFLAG)) {
RESTORE_ERRNO();
return;
}
v = l->rd_cv;
atomic_add_int(&l->rd_waiters, 1);
while (l->lock & WAFLAG) {
@ -109,6 +130,7 @@ _thr_rtld_rlock_acquire(void *lock)
v = l->rd_cv;
}
atomic_add_int(&l->rd_waiters, -1);
RESTORE_ERRNO();
}
static void
@ -117,14 +139,18 @@ _thr_rtld_wlock_acquire(void *lock)
struct pthread *curthread;
struct rtld_lock *l;
long v;
int errsave;
curthread = _get_curthread();
SAVE_ERRNO();
l = (struct rtld_lock *)lock;
_thr_signal_block(curthread);
for (;;) {
if (atomic_cmpset_acq_int(&l->lock, 0, WAFLAG))
if (atomic_cmpset_acq_int(&l->lock, 0, WAFLAG)) {
RESTORE_ERRNO();
return;
}
v = l->wr_cv;
atomic_add_int(&l->wr_waiters, 1);
while (l->lock != 0) {
@ -140,8 +166,10 @@ _thr_rtld_lock_release(void *lock)
{
struct pthread *curthread;
struct rtld_lock *l;
int errsave;
curthread = _get_curthread();
SAVE_ERRNO();
l = (struct rtld_lock *)lock;
if ((l->lock & WAFLAG) == 0) {
@ -162,6 +190,7 @@ _thr_rtld_lock_release(void *lock)
}
_thr_signal_unblock(curthread);
}
RESTORE_ERRNO();
}
static int