11dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project/* $OpenBSD: atexit.c,v 1.14 2007/09/05 20:47:47 chl Exp $ */ 21dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project/* 31dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * Copyright (c) 2002 Daniel Hartmeier 41dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * All rights reserved. 51dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * 61dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * Redistribution and use in source and binary forms, with or without 71dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * modification, are permitted provided that the following conditions 81dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * are met: 91dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * 101dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * - Redistributions of source code must retain the above copyright 111dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * notice, this list of conditions and the following disclaimer. 121dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * - Redistributions in binary form must reproduce the above 131dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * copyright notice, this list of conditions and the following 141dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * disclaimer in the documentation and/or other materials provided 151dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * with the distribution. 161dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * 171dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 181dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 191dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 201dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 211dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 221dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 231dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 241dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 251dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 261dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 271dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 281dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * POSSIBILITY OF SUCH DAMAGE. 291dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * 301dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project */ 311dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 321dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project#include <sys/types.h> 331dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project#include <sys/mman.h> 341dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project#include <stdlib.h> 351dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project#include <string.h> 361dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project#include <unistd.h> 371dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project#include "atexit.h" 381dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project#include "thread_private.h" 391dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 401dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Projectint __atexit_invalid = 1; 411dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Projectstruct atexit *__atexit; 421dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 431dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project/* 441dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * Function pointers are stored in a linked list of pages. The list 451dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * is initially empty, and pages are allocated on demand. The first 461dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * function pointer in the first allocated page (the last one in 4761e699a133a4807fe878a6cb0d7190d7c96e21f8Elliott Hughes * the linked list) was reserved for the cleanup function. 4861e699a133a4807fe878a6cb0d7190d7c96e21f8Elliott Hughes * TODO: switch to the regular FreeBSD/NetBSD atexit implementation. 491dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * 501dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * Outside the following functions, all pages are mprotect()'ed 511dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * to prevent unintentional/malicious corruption. 521dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project */ 531dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 541dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project/* 551dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * Register a function to be performed at exit or when a shared object 561dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * with the given dso handle is unloaded dynamically. Also used as 571dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * the backend for atexit(). For more info on this API, see: 581dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * 591dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * http://www.codesourcery.com/cxx-abi/abi.html#dso-dtor 601dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project */ 611dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Projectint 621dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project__cxa_atexit(void (*func)(void *), void *arg, void *dso) 631dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project{ 641dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project struct atexit *p = __atexit; 651dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project struct atexit_fn *fnp; 661dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project int pgsize = getpagesize(); 671dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project int ret = -1; 681dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 691dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (pgsize < (int)sizeof(*p)) 701dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return (-1); 711dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project _ATEXIT_LOCK(); 721dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project p = __atexit; 731dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (p != NULL) { 741dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (p->ind + 1 >= p->max) 751dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project p = NULL; 761dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project else if (mprotect(p, pgsize, PROT_READ | PROT_WRITE)) 771dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project goto unlock; 781dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } 791dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (p == NULL) { 801dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project p = mmap(NULL, pgsize, PROT_READ | PROT_WRITE, 811dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project MAP_ANON | MAP_PRIVATE, -1, 0); 821dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (p == MAP_FAILED) 831dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project goto unlock; 841dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (__atexit == NULL) { 851dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project memset(&p->fns[0], 0, sizeof(p->fns[0])); 861dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project p->ind = 1; 871dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } else 881dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project p->ind = 0; 891dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project p->max = (pgsize - ((char *)&p->fns[0] - (char *)p)) / 901dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project sizeof(p->fns[0]); 911dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project p->next = __atexit; 921dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project __atexit = p; 931dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (__atexit_invalid) 941dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project __atexit_invalid = 0; 951dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } 961dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project fnp = &p->fns[p->ind++]; 971dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project fnp->fn_ptr.cxa_func = func; 981dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project fnp->fn_arg = arg; 991dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project fnp->fn_dso = dso; 1001dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (mprotect(p, pgsize, PROT_READ)) 1011dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project goto unlock; 1021dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project ret = 0; 1031dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Projectunlock: 1041dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project _ATEXIT_UNLOCK(); 1051dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return (ret); 1061dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project} 1071dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 1081dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project/* 1091dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * Call all handlers registered with __cxa_atexit() for the shared 1101dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * object owning 'dso'. 1111dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * Note: if 'dso' is NULL, then all remaining handlers are called. 1121dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project */ 1131dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Projectvoid 1141dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project__cxa_finalize(void *dso) 1151dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project{ 1161dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project struct atexit *p, *q; 1171dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project struct atexit_fn fn; 1181dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project int n, pgsize = getpagesize(); 1191dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project static int call_depth; 1201dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 1211dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (__atexit_invalid) 1221dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return; 1231dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 1242270dfa0c418ab06e89412ea7b4ffe650490bcc9Srinavasa Nagaraju _ATEXIT_LOCK(); 1251dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project call_depth++; 1261dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 1271dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project for (p = __atexit; p != NULL; p = p->next) { 1281dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project for (n = p->ind; --n >= 0;) { 1291dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (p->fns[n].fn_ptr.cxa_func == NULL) 1301dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project continue; /* already called */ 1311dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (dso != NULL && dso != p->fns[n].fn_dso) 1321dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project continue; /* wrong DSO */ 1331dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 1341dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project /* 1351dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * Mark handler as having been already called to avoid 1361dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * dupes and loops, then call the appropriate function. 1371dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project */ 1381dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project fn = p->fns[n]; 1391dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (mprotect(p, pgsize, PROT_READ | PROT_WRITE) == 0) { 1401dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project p->fns[n].fn_ptr.cxa_func = NULL; 1411dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project mprotect(p, pgsize, PROT_READ); 1421dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } 1432270dfa0c418ab06e89412ea7b4ffe650490bcc9Srinavasa Nagaraju _ATEXIT_UNLOCK(); 1440ba91ed3ca9e7340a2c55303034c3378967e2327David 'Digit' Turner#if ANDROID 1450ba91ed3ca9e7340a2c55303034c3378967e2327David 'Digit' Turner /* it looks like we should always call the function 1460ba91ed3ca9e7340a2c55303034c3378967e2327David 'Digit' Turner * with an argument, even if dso is not NULL. Otherwise 1470ba91ed3ca9e7340a2c55303034c3378967e2327David 'Digit' Turner * static destructors will not be called properly on 1480ba91ed3ca9e7340a2c55303034c3378967e2327David 'Digit' Turner * the ARM. 1490ba91ed3ca9e7340a2c55303034c3378967e2327David 'Digit' Turner */ 1500ba91ed3ca9e7340a2c55303034c3378967e2327David 'Digit' Turner (*fn.fn_ptr.cxa_func)(fn.fn_arg); 1510ba91ed3ca9e7340a2c55303034c3378967e2327David 'Digit' Turner#else /* !ANDROID */ 1521dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (dso != NULL) 1531dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project (*fn.fn_ptr.cxa_func)(fn.fn_arg); 1541dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project else 1551dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project (*fn.fn_ptr.std_func)(); 1560ba91ed3ca9e7340a2c55303034c3378967e2327David 'Digit' Turner#endif /* !ANDROID */ 1572270dfa0c418ab06e89412ea7b4ffe650490bcc9Srinavasa Nagaraju _ATEXIT_LOCK(); 1581dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } 1591dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } 1601dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 1611dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project /* 1621dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * If called via exit(), unmap the pages since we have now run 1631dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * all the handlers. We defer this until calldepth == 0 so that 1641dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * we don't unmap things prematurely if called recursively. 1651dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project */ 1661dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (dso == NULL && --call_depth == 0) { 1671dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project for (p = __atexit; p != NULL; ) { 1681dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project q = p; 1691dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project p = p->next; 1701dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project munmap(q, pgsize); 1711dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } 1721dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project __atexit = NULL; 1731dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } 1742270dfa0c418ab06e89412ea7b4ffe650490bcc9Srinavasa Nagaraju _ATEXIT_UNLOCK(); 1751dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project} 176