1/* libunwind - a platform-independent unwind library 2 Copyright (C) 2003-2004 Hewlett-Packard Co 3 Contributed by David Mosberger-Tang <davidm@hpl.hp.com> 4 5This file is part of libunwind. 6 7Permission is hereby granted, free of charge, to any person obtaining 8a copy of this software and associated documentation files (the 9"Software"), to deal in the Software without restriction, including 10without limitation the rights to use, copy, modify, merge, publish, 11distribute, sublicense, and/or sell copies of the Software, and to 12permit persons to whom the Software is furnished to do so, subject to 13the following conditions: 14 15The above copyright notice and this permission notice shall be 16included in all copies or substantial portions of the Software. 17 18THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 19EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 20MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 21NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE 22LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 23OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 24WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ 25 26#define UNW_LOCAL_ONLY 27 28#undef _FORTIFY_SOURCE 29#include <assert.h> 30#include <libunwind.h> 31#include <setjmp.h> 32#include <signal.h> 33#include <stdlib.h> 34 35#include "jmpbuf.h" 36#include "setjmp_i.h" 37 38#if defined(__GLIBC__) 39#if __GLIBC_PREREQ(2, 4) 40 41/* Starting with glibc-2.4, {sig,}setjmp in GLIBC obfuscates the 42 register values in jmp_buf by XORing them with a "random" 43 canary value. 44 45 This makes it impossible to implement longjmp, as we 46 can never match wp[JB_SP], unless we decode the canary first. 47 48 Doing so is possible, but doesn't appear to be worth the trouble, 49 so we simply defer to glibc longjmp here. */ 50#define _longjmp __nonworking__longjmp 51#define longjmp __nonworking_longjmp 52static void _longjmp (jmp_buf env, int val); 53static void longjmp (jmp_buf env, int val); 54#endif 55#endif /* __GLIBC__ */ 56 57void 58_longjmp (jmp_buf env, int val) 59{ 60 extern int _UI_longjmp_cont; 61 unw_context_t uc; 62 unw_cursor_t c; 63 unw_word_t sp; 64 unw_word_t *wp = (unw_word_t *) env; 65 66 if (unw_getcontext (&uc) < 0 || unw_init_local (&c, &uc) < 0) 67 abort (); 68 69 do 70 { 71 if (unw_get_reg (&c, UNW_REG_SP, &sp) < 0) 72 abort (); 73#ifdef __FreeBSD__ 74 if (sp != wp[JB_SP] + sizeof(unw_word_t)) 75#else 76 if (sp != wp[JB_SP]) 77#endif 78 continue; 79 80 if (!bsp_match (&c, wp)) 81 continue; 82 83 /* found the right frame: */ 84 85 assert (UNW_NUM_EH_REGS >= 2); 86 87 if (unw_set_reg (&c, UNW_REG_EH + 0, wp[JB_RP]) < 0 88 || unw_set_reg (&c, UNW_REG_EH + 1, val) < 0 89 || unw_set_reg (&c, UNW_REG_IP, 90 (unw_word_t) (uintptr_t) &_UI_longjmp_cont)) 91 abort (); 92 93 unw_resume (&c); 94 95 abort (); 96 } 97 while (unw_step (&c) > 0); 98 99 abort (); 100} 101 102#ifdef __GNUC__ 103#define STRINGIFY1(x) #x 104#define STRINGIFY(x) STRINGIFY1(x) 105void longjmp (jmp_buf env, int val) 106 __attribute__ ((alias (STRINGIFY(_longjmp)))); 107#else 108 109void 110longjmp (jmp_buf env, int val) 111{ 112 _longjmp (env, val); 113} 114 115#endif /* __GNUC__ */ 116