clone.cpp revision c4c6e192ac045c06f4aad3afc8e437baf67227b7
197cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner/* 297cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * Copyright (C) 2010 The Android Open Source Project 397cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * All rights reserved. 497cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * 597cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * Redistribution and use in source and binary forms, with or without 697cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * modification, are permitted provided that the following conditions 797cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * are met: 897cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * * Redistributions of source code must retain the above copyright 997cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * notice, this list of conditions and the following disclaimer. 1097cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * * Redistributions in binary form must reproduce the above copyright 1197cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * notice, this list of conditions and the following disclaimer in 1297cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * the documentation and/or other materials provided with the 1397cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * distribution. 1497cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * 1597cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 1697cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 1797cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 1897cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 1997cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 2097cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 2197cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 2297cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 2397cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 2497cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 2597cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 2697cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * SUCH DAMAGE. 2797cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner */ 2897cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner#define __GNU_SOURCE 1 2997cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner#include <sched.h> 3097cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner#include <stdlib.h> 3197cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner#include <stdarg.h> 3297cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner#include <stdio.h> 3397cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner 3497cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turnerextern int __bionic_clone(unsigned long clone_flags, 3597cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner void* newsp, 3697cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner int *parent_tidptr, 3797cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner void *new_tls, 3897cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner int *child_tidptr, 3997cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner int (*fn)(void *), 4097cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner void *arg); 4197cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner 42c4c6e192ac045c06f4aad3afc8e437baf67227b7Elliott Hughesextern void _exit_thread(int status); 4397cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner 4497cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner/* this function is called from the __bionic_clone 4597cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * assembly fragment to call the thread function 4697cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner * then exit. */ 47c4c6e192ac045c06f4aad3afc8e437baf67227b7Elliott Hughesextern void __bionic_clone_entry(int (*fn)(void*), void* arg) { 48c4c6e192ac045c06f4aad3afc8e437baf67227b7Elliott Hughes int status = (*fn)(arg); 49c4c6e192ac045c06f4aad3afc8e437baf67227b7Elliott Hughes _exit_thread(status); 5097cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner} 5197cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner 52c4c6e192ac045c06f4aad3afc8e437baf67227b7Elliott Hughesint clone(int (*fn)(void*), void* child_stack, int flags, void* arg, ...) { 5397cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner va_list args; 5497cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner int *parent_tidptr = NULL; 5597cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner void *new_tls = NULL; 5697cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner int *child_tidptr = NULL; 5797cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner 5840eabe24e4e3ae8ebe437f1f4e43cf39cbba2e9eElliott Hughes /* extract optional parameters - they are cumulative. */ 5997cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner va_start(args, arg); 6097cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner if (flags & (CLONE_PARENT_SETTID|CLONE_SETTLS|CLONE_CHILD_SETTID)) { 6197cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner parent_tidptr = va_arg(args, int*); 6297cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner } 6397cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner if (flags & (CLONE_SETTLS|CLONE_CHILD_SETTID)) { 6497cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner new_tls = va_arg(args, void*); 6597cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner } 6697cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner if (flags & CLONE_CHILD_SETTID) { 6797cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner child_tidptr = va_arg(args, int*); 6897cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner } 6997cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner va_end(args); 7097cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner 7140eabe24e4e3ae8ebe437f1f4e43cf39cbba2e9eElliott Hughes return __bionic_clone(flags, child_stack, parent_tidptr, new_tls, child_tidptr, fn, arg); 7297cf7f3394780d524038fc083e2c134031b54728David 'Digit' Turner} 73