Make perl fork()-safe (in a slightly limited way) even on

platforms that don't have pthread_atfork() (extension of
the fix in change#11151).

Note that this will not help extensions that call fork()
directly in C, or that link to libraries that call fork()
directly.  Such cases must be fixed to either call
PerlProc_fork(), or call atfork_lock() in parent before the
calling the function that forks and call atfork_unlock()
in both parent and child immediately after the fork().
(There are no worries if C code calls exec() in the child
immediately after a fork().  Only cases where the child
calls perl's API functions (including New()) after the
fork() are problematic.)

This change also eliminates the use of vfork() from perl,
since all such uses were violating the severe restrictions
on modifying the state of the process between the vfork()
and the exec().

This is a modified version of patches suggested by Abhijit
Menon-Sen and Richard Soderberg.

p4raw-link: @11151 on //depot/perl: 50dd6e574ff39b609595ddb16b2fe9f625a26f8c

p4raw-id: //depot/perl@11423

1 files changed, 0 insertions, 23 deletions

diff --git a/perl.c b/perl.c
index 25cdcd6e4b..322960d211 100644
--- a/perl.c
+++ b/perl.c
@@ -58,29 +58,6 @@ static I32 read_e_script(pTHXo_ int idx, SV *buf_sv, int maxlen);
     } STMT_END
 #else
 #  if defined(USE_ITHREADS)
-
-/* this is called in parent before the fork() */
-void
-Perl_atfork_lock(void)
-{
-    /* locks must be held in locking order (if any) */
-#ifdef MYMALLOC
-    MUTEX_LOCK(&PL_malloc_mutex);
-#endif
-    OP_REFCNT_LOCK;
-}
-
-/* this is called in both parent and child after the fork() */
-void
-Perl_atfork_unlock(void)
-{
-    /* locks must be released in same order as in S_atfork_lock() */
-#ifdef MYMALLOC
-    MUTEX_UNLOCK(&PL_malloc_mutex);
-#endif
-    OP_REFCNT_UNLOCK;
-}
-
 #  define INIT_TLS_AND_INTERP \
     STMT_START {				\
 	if (!PL_curinterp) {			\