procyberian/emacs
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Fix crashes when unbind_for_thread_switch signals an error.

Browse source 
src/eval.c (unbind_for_thread_switch): Accept a 'struct
 thread_state *' argument and use specpdl_ptr and specpdl of that
 thread.  Fixes crashes if find_symbol_value signals an error.
 src/thread.c (post_acquire_global_lock): Update current_thread
 before calling unbind_for_thread_switch.  Pass the previous thread
 to unbind_for_thread_switch.
This commit is contained in:
Eli Zaretskii 2013-09-01 18:43:43 +03:00
parent e57df8f779
commit bed10876db
4 changed files with 23 additions and 8 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

10
src/ChangeLog
View file

@ -1,3 +1,13 @@
2013-09-01 Eli Zaretskii <eliz@gnu.org>
* eval.c (unbind_for_thread_switch): Accept a 'struct
thread_state *' argument and use specpdl_ptr and specpdl of that
thread. Fixes crashes if find_symbol_value signals an error.
* thread.c (post_acquire_global_lock): Update current_thread
before calling unbind_for_thread_switch. Pass the previous thread
to unbind_for_thread_switch.
2013-08-31 Eli Zaretskii <eliz@gnu.org>
* systhread.c (sys_cond_init): Set the 'initialized' member to

4
src/eval.c
View file

@ -3484,11 +3484,11 @@ unbind_to (ptrdiff_t count, Lisp_Object value)
}
void
unbind_for_thread_switch (void)
unbind_for_thread_switch (struct thread_state *thr)
{
union specbinding *bind;
for (bind = specpdl_ptr; bind != specpdl; --bind)
for (bind = thr->m_specpdl_ptr; bind != thr->m_specpdl; --bind)
{
if (bind->kind >= SPECPDL_LET)
{

2
src/lisp.h
View file

@ -3828,7 +3828,7 @@ extern void set_unwind_protect (ptrdiff_t, void (*) (Lisp_Object), Lisp_Object);
extern void set_unwind_protect_ptr (ptrdiff_t, void (*) (void *), void *);
extern Lisp_Object unbind_to (ptrdiff_t, Lisp_Object);
extern void rebind_for_thread_switch (void);
extern void unbind_for_thread_switch (void);
extern void unbind_for_thread_switch (struct thread_state *);
extern _Noreturn void error (const char *, ...) ATTRIBUTE_FORMAT_PRINTF (1, 2);
extern _Noreturn void verror (const char *, va_list)
ATTRIBUTE_FORMAT_PRINTF (1, 0);

15
src/thread.c
View file

@ -55,15 +55,20 @@ static void
post_acquire_global_lock (struct thread_state *self)
{
Lisp_Object buffer;
struct thread_state *prev_thread = current_thread;
if (self != current_thread)
/* Do this early on, so that code below could signal errors (e.g.,
unbind_for_thread_switch might) correctly, because we are already
running in the context of the thread pointed by SELF. */
current_thread = self;
if (prev_thread != current_thread)
{
/* CURRENT_THREAD is NULL if the previously current thread
/* PREV_THREAD is NULL if the previously current thread
exited. In this case, there is no reason to unbind, and
trying will crash. */
if (current_thread != NULL)
unbind_for_thread_switch ();
current_thread = self;
if (prev_thread != NULL)
unbind_for_thread_switch (prev_thread);
rebind_for_thread_switch ();
}