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-rw-r--r--ports/sysdeps/unix/sysv/linux/arm/vfork.S60
1 files changed, 60 insertions, 0 deletions
diff --git a/ports/sysdeps/unix/sysv/linux/arm/vfork.S b/ports/sysdeps/unix/sysv/linux/arm/vfork.S
new file mode 100644
index 0000000000..abd46c1c3b
--- /dev/null
+++ b/ports/sysdeps/unix/sysv/linux/arm/vfork.S
@@ -0,0 +1,60 @@
+/* Copyright (C) 1999-2012 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Philip Blundell <philb@gnu.org>.
+
+ 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, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <sysdep.h>
+#define _ERRNO_H 1
+#include <bits/errno.h>
+
+/* Clone the calling process, but without copying the whole address space.
+ The calling process is suspended until the new process exits or is
+ replaced by a call to `execve'. Return -1 for errors, 0 to the new process,
+ and the process ID of the new process to the old process. */
+
+ENTRY (__vfork)
+#ifdef SAVE_PID
+ SAVE_PID
+#endif
+ /* The DO_CALL macro saves r7 on the stack, to enable generation
+ of ARM unwind info. Since the stack is initially shared between
+ parent and child of vfork, that saved value could be corrupted.
+ To avoid this problem, we save r7 into ip as well, and restore
+ from there. */
+ mov ip, r7
+ cfi_register (r7, ip)
+ .fnstart
+ str r7, [sp, #-4]!
+ cfi_adjust_cfa_offset (4)
+ .save { r7 }
+ ldr r7, =SYS_ify (vfork)
+ swi 0x0
+ .fnend
+ add sp, sp, #4
+ cfi_adjust_cfa_offset (-4)
+ mov r7, ip
+ cfi_restore (r7);
+#ifdef RESTORE_PID
+ RESTORE_PID
+#endif
+ cmn a1, #4096
+ RETINSTR(cc, lr)
+
+ b PLTJMP(SYSCALL_ERROR)
+PSEUDO_END (__vfork)
+libc_hidden_def (__vfork)
+
+weak_alias (__vfork, vfork)