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authorUlrich Drepper <drepper@redhat.com>1996-08-11 01:08:23 +0000
committerUlrich Drepper <drepper@redhat.com>1996-08-11 01:08:23 +0000
commit267ca16a67be70e0361c212e805d43884aee4506 (patch)
tree5866c33fdf3e7366ae9d89ed71e0683fbbf8517c /sysdeps/unix/sysv/linux/i386/clone.S
parentf2b5d40e87c64a1bd855e9408bd81ab508eade87 (diff)
Sat Aug 10 13:17:27 1996 David Mosberger-Tang <davidm@azstarnet.com> * shadow.h: New file. * sysdeps/unix/sysv/linux/netinet/in.h: Move __BEGIN_DECLS/__END_DECLS up so ntohl() et al are bracketed as well. * socket/sys/socket.h [__cplusplus]: Use old-style __SOCKADDR_ARG. g++ 2.7.2 (and earlier) has no transparent unions support. Fri Aug 9 18:50:06 1996 David Mosberger-Tang <davidm@azstarnet.com> * sysdeps/unix/sysv/linux/alpha/ioperm.c (_bus_base_sparse): New function to determine the base address of sparse bus memory. (APECS_*): Rename to CIA_*. (APECS_SPARSE_MEM, CIA_SPARSE_MEM): New macros. (platform): Add sparse_bus_memory_base member and initialize. (sparse_bus_memory_base): New variable. Tue Aug 6 10:23:18 1996 David Mosberger-Tang <davidm@azstarnet.com> * sysdeps/posix/ttyname_r.c (ttyname_r), sysdeps/posix/ttyname.c (ttyname): Return -1/NULL if !__isatty(fd) (POSIX.1 says so.) * sysdeps/unix/getlogin.c (getlogin): Fix to check fd 0 only. This is not a gross hack, after all---for compatibility, getlogin() really should check fd 0 only and not try to base its operation on the controlling tty. Wed Jul 17 10:54:20 1996 David Mosberger-Tang <davidm@azstarnet.com> * sysdeps/unix/getlogin.c (getlogin): Add static variable NAME, change utmp_data from static to auto. Sun Aug 11 02:56:08 1996 Ulrich Drepper <drepper@cygnus.com> * posix/unistd.h [__USE_MISC]: Add prototype for `nice'. Reported by David Mosberger-Tang.
Diffstat (limited to 'sysdeps/unix/sysv/linux/i386/clone.S')
-rw-r--r--sysdeps/unix/sysv/linux/i386/clone.S80
1 files changed, 80 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/i386/clone.S b/sysdeps/unix/sysv/linux/i386/clone.S
new file mode 100644
index 0000000000..02f561927e
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/i386/clone.S
@@ -0,0 +1,80 @@
+/* Copyright (C) 1996 Free Software Foundation, Inc.
+ Contributed by Richard Henderson (rth@tamu.edu)
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 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
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB. If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA. */
+
+/* clone() is even more special than fork() as it mucks with stacks
+ and invokes a function in the right context after its all over. */
+
+#include <sysdep.h>
+#include <errnos.h>
+
+/* int clone(int (*fn)(), void *child_stack, int flags, int nargs, ...) */
+
+ .text
+ENTRY(__clone)
+ /* Sanity check arguments. */
+ movl $-EINVAL,%eax
+ movl 4(%esp),%ecx /* no NULL function pointers */
+ testl %ecx,%ecx
+ jz syscall_error
+ movl 8(%esp),%ecx /* no NULL stack pointers */
+ testl %ecx,%ecx
+ jz syscall_error
+ movl 16(%esp),%edx /* no negative argument counts */
+ testl %edx,%edx
+ js syscall_error
+
+ /* Allocate space on the new stack and copy args over */
+ movl %edx,%eax
+ negl %eax
+ lea -4(%ecx,%eax,4),%ecx
+ jz 2f
+1: movl 16(%esp,%edx,4),%eax
+ movl %eax,0(%ecx,%edx,4)
+ dec %edx
+ jnz 1b
+2:
+ /* Save the function pointer as the zeroth argument.
+ It will be popped off in the child in the ebx frobbing below. */
+ movl 4(%esp),%eax
+ movl %eax,0(%ecx)
+
+ /* Do the system call */
+ pushl %ebx
+ movl 16(%esp),%ebx
+ movl $SYS_ify(clone),%eax
+ int $0x80
+ popl %ebx
+
+ test %eax,%eax
+ jl syscall_error
+ jz thread_start
+
+ ret
+
+ SYSCALL_ERROR_HANDLER
+
+thread_start:
+ subl %ebp,%ebp /* terminate the stack frame */
+ call *%ebx
+#ifdef PIC
+ call _exit@PLT
+#else
+ call _exit
+#endif
+
+weak_alias(__clone, clone)