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-rw-r--r--nptl/sysdeps/unix/sysv/linux/fork.c124
1 files changed, 124 insertions, 0 deletions
diff --git a/nptl/sysdeps/unix/sysv/linux/fork.c b/nptl/sysdeps/unix/sysv/linux/fork.c
new file mode 100644
index 0000000000..c1aa23c5c5
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+++ b/nptl/sysdeps/unix/sysv/linux/fork.c
@@ -0,0 +1,124 @@
+/* Copyright (C) 2002 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sysdep.h>
+#include <libio/libioP.h>
+#include <tls.h>
+#include "fork.h"
+
+
+unsigned long int *__fork_generation_pointer;
+
+
+lll_lock_t __fork_lock = LLL_LOCK_INITIALIZER;
+LIST_HEAD (__fork_prepare_list);
+LIST_HEAD (__fork_parent_list);
+LIST_HEAD (__fork_child_list);
+
+
+static void
+fresetlockfiles (void)
+{
+ _IO_ITER i;
+
+ for (i = _IO_iter_begin(); i != _IO_iter_end(); i = _IO_iter_next(i))
+ *((pthread_mutex_t *) _IO_iter_file(i)->_lock)
+ = (pthread_mutex_t) PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP;
+}
+
+
+pid_t
+__libc_fork (void)
+{
+ pid_t pid;
+ list_t *runp;
+
+ /* Get the lock so that the set of registered handlers is not
+ inconsistent or changes beneath us. */
+ lll_lock (__fork_lock);
+
+ /* Run all the registered preparation handlers. In reverse order. */
+ list_for_each_prev (runp, &__fork_prepare_list)
+ {
+ struct fork_handler *curp;
+
+ curp = list_entry (runp, struct fork_handler, list);
+
+ curp->handler ();
+ }
+
+ _IO_list_lock ();
+
+#ifdef ARCH_FORK
+ pid = ARCH_FORK ();
+#else
+# error "ARCH_FORK must be defined so that the CLONE_SETTID flag is used"
+ pid = INLINE_SYSCALL (fork, 0);
+#endif
+
+ if (pid == 0)
+ {
+ if (__fork_generation_pointer != NULL)
+ *__fork_generation_pointer += 4;
+
+ /* Reset the file list. These are recursive mutexes. */
+ fresetlockfiles ();
+
+ /* We execute this even if the 'fork' call failed. */
+ _IO_list_resetlock ();
+
+ /* Run the handlers registered for the child. */
+ list_for_each (runp, &__fork_child_list)
+ {
+ struct fork_handler *curp;
+
+ curp = list_entry (runp, struct fork_handler, list);
+
+ curp->handler ();
+ }
+
+ /* Initialize the fork lock. */
+ __fork_lock = (lll_lock_t) LLL_LOCK_INITIALIZER;
+ }
+ else
+ {
+ /* We execute this even if the 'fork' call failed. */
+ _IO_list_unlock ();
+
+ /* Run the handlers registered for the parent. */
+ list_for_each (runp, &__fork_parent_list)
+ {
+ struct fork_handler *curp;
+
+ curp = list_entry (runp, struct fork_handler, list);
+
+ curp->handler ();
+ }
+
+ /* Release the for lock. */
+ lll_unlock (__fork_lock);
+ }
+
+ return pid;
+}
+weak_alias (__libc_fork, __fork)
+weak_alias (__libc_fork, fork)