diff options
Diffstat (limited to 'REORG.TODO/sysdeps/unix/sysv/linux/i386/setcontext.S')
| -rw-r--r-- | REORG.TODO/sysdeps/unix/sysv/linux/i386/setcontext.S | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/unix/sysv/linux/i386/setcontext.S b/REORG.TODO/sysdeps/unix/sysv/linux/i386/setcontext.S new file mode 100644 index 0000000000..c6fa618a01 --- /dev/null +++ b/REORG.TODO/sysdeps/unix/sysv/linux/i386/setcontext.S @@ -0,0 +1,96 @@ +/* Install given context. + Copyright (C) 2001-2017 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper <drepper@redhat.com>, 2001. + + 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> + +#include "ucontext_i.h" + + +ENTRY(__setcontext) + /* Load address of the context data structure. */ + movl 4(%esp), %eax + + /* Get the current signal mask. Note that we preserve EBX in case + the system call fails and we return from the function with an + error. */ + pushl %ebx + cfi_adjust_cfa_offset (4) + xorl %edx, %edx + leal oSIGMASK(%eax), %ecx + movl $SIG_SETMASK, %ebx + cfi_rel_offset (ebx, 0) + movl $__NR_sigprocmask, %eax + ENTER_KERNEL + popl %ebx + cfi_adjust_cfa_offset (-4) + cfi_restore (ebx) + cmpl $-4095, %eax /* Check %eax for error. */ + jae SYSCALL_ERROR_LABEL /* Jump to error handler if error. */ + + /* EAX was modified, reload it. */ + movl 4(%esp), %eax + + /* Restore the floating-point context. Not the registers, only the + rest. */ + movl oFPREGS(%eax), %ecx + fldenv (%ecx) + + /* Restore the FS segment register. We don't touch the GS register + since it is used for threads. */ + movl oFS(%eax), %ecx + movw %cx, %fs + + /* Fetch the address to return to. */ + movl oEIP(%eax), %ecx + + /* Load the new stack pointer. */ + cfi_def_cfa (eax, 0) + cfi_offset (edi, oEDI) + cfi_offset (esi, oESI) + cfi_offset (ebp, oEBP) + cfi_offset (ebx, oEBX) + cfi_offset (edx, oEDX) + cfi_offset (ecx, oECX) + movl oESP(%eax), %esp + + /* Push the return address on the new stack so we can return there. */ + pushl %ecx + + /* Load the values of all the 32-bit registers (except ESP). + Since we are loading from EAX, it must be last. */ + movl oEDI(%eax), %edi + movl oESI(%eax), %esi + movl oEBP(%eax), %ebp + movl oEBX(%eax), %ebx + movl oEDX(%eax), %edx + movl oECX(%eax), %ecx + movl oEAX(%eax), %eax + + /* End FDE here, we fall into another context. */ + cfi_endproc + cfi_startproc + + /* The following 'ret' will pop the address of the code and jump + to it. */ + + ret +PSEUDO_END(__setcontext) +libc_hidden_def (__setcontext) + +weak_alias (__setcontext, setcontext) |