diff options
Diffstat (limited to 'libc/sysdeps/linux/mips/clone.S')
-rw-r--r-- | libc/sysdeps/linux/mips/clone.S | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/libc/sysdeps/linux/mips/clone.S b/libc/sysdeps/linux/mips/clone.S new file mode 100644 index 000000000..6f6a6c5b7 --- /dev/null +++ b/libc/sysdeps/linux/mips/clone.S @@ -0,0 +1,107 @@ +/* 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) |