nptl: Implement raise in terms of pthread_kill

Now that pthread_kill is provided by libc.so it is possible to
implement the generic POSIX implementation as
'pthread_kill(pthread_self(), sig)'.

For Linux implementation, pthread_kill read the targeting TID from
the TCB.  For raise, this it not possible because it would make raise
fail when issue after vfork (where creates the resulting process
has a different TID from the parent, but its TCB is not updated as
for pthread_create).  To make raise use pthread_kill, it is make
usable from vfork by getting the target thread id through gettid
syscall.

Checked on x86_64-linux-gnu and aarch64-linux-gnu.

1 files changed, 3 insertions, 1 deletions

diff --git a/nptl/pthreadP.h b/nptl/pthreadP.h
index 3e7a4f52ab..618922f47a 100644
--- a/nptl/pthreadP.h
+++ b/nptl/pthreadP.h
@@ -508,11 +508,13 @@ extern int __pthread_once (pthread_once_t *once_control,
 libc_hidden_proto (__pthread_once)
 extern int __pthread_atfork (void (*prepare) (void), void (*parent) (void),
 			     void (*child) (void));
-extern pthread_t __pthread_self (void);
+libc_hidden_proto (__pthread_self)
 extern int __pthread_equal (pthread_t thread1, pthread_t thread2);
 extern int __pthread_detach (pthread_t th);
 libc_hidden_proto (__pthread_detach)
 extern int __pthread_kill (pthread_t threadid, int signo);
+libc_hidden_proto (__pthread_kill)
+extern int __pthread_cancel (pthread_t th);
 extern void __pthread_exit (void *value) __attribute__ ((__noreturn__));
 libc_hidden_proto (__pthread_exit)
 extern int __pthread_join (pthread_t threadid, void **thread_return);