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-rw-r--r--libc/sysdeps/linux/mips/clone.S107
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diff --git a/libc/sysdeps/linux/mips/clone.S b/libc/sysdeps/linux/mips/clone.S
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+/* Copyright (C) 1996, 1997, 2000 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Ralf Baechle <ralf@gnu.ai.mit.edu>, 1996.
+
+ 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. */
+
+/* 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 <asm/unistd.h>
+#include <sysdep.h>
+#define _ERRNO_H 1
+#include <bits/errno.h>
+
+/* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg) */
+
+ .text
+NESTED(__clone,4*SZREG,sp)
+#ifdef __PIC__
+ .set noreorder
+ .cpload $25
+ .set reorder
+ subu sp,32
+ .cprestore 16
+#else
+ subu sp,32
+#endif
+#ifdef PROF
+ .set noat
+ move $1,ra
+ jal _mcount
+ .set at
+#endif
+
+
+ /* Sanity check arguments. */
+ li v0,EINVAL
+ beqz a0,error /* No NULL function pointers. */
+ beqz a1,error /* No NULL stack pointers. */
+
+ subu a1,32 /* Reserve argument save space. */
+ sw a0,0(a1) /* Save function pointer. */
+ sw a3,4(a1) /* Save argument pointer. */
+
+
+ /* Do the system call */
+ move a0,a2
+ li v0,__NR_clone
+ syscall
+
+ bnez a3,error
+ beqz v0,__thread_start
+
+ /* Successful return from the parent */
+ addiu sp,32
+ ret
+
+ /* Something bad happened -- no child created */
+error:
+ addiu sp,32
+#ifdef __PIC__
+ la t9,__syscall_error
+ jr t9
+#else
+ j __syscall_error
+#endif
+ END(__clone)
+
+/* Load up the arguments to the function. Put this block of code in
+ its own function so that we can terminate the stack trace with our
+ debug info. */
+
+ENTRY(__thread_start)
+ /* cp is already loaded. */
+ .cprestore 16
+ /* The stackframe has been created on entry of clone(). */
+ /* Restore the arg for user's function. */
+ lw t9,0(sp) /* Function pointer. */
+ lw a0,4(sp) /* Argument pointer. */
+
+ /* Call the user's function. */
+ jalr t9
+
+ /* Call _exit rather than doing it inline for breakpoint purposes. */
+ move a0,v0
+#ifdef __PIC__
+ la t9,_exit
+ jalr t9
+#else
+ jal _exit
+#endif
+ END(__thread_start)
+
+weak_alias(__clone, clone)