/* * Copyright (C) 2013 The Android Open Source Project * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include #include // This custom code preserves the return address across the system call. ENTRY(vfork) __BIONIC_WEAK_ASM_FOR_NATIVE_BRIDGE(vfork) popq %rdi // Grab the return address. // Set cached_pid_ to 0, vforked_ to 1, and stash the previous value. mov %fs:0, %r8 mov (TLS_SLOT_THREAD_ID * 8)(%r8), %r8 movl 20(%r8), %r9d movl $0x80000000, 20(%r8) movl $__NR_vfork, %eax syscall pushq %rdi // Restore the return address. test %eax, %eax jz 1f // rc != 0: restore the previous cached_pid_/vforked_ values. movl %r9d, 20(%r8) cmpq $-MAX_ERRNO, %rax jb 1f negl %eax movl %eax, %edi call __set_errno_internal 1: ret END(vfork)