/* libunwind - a platform-independent unwind library Copyright (C) 2003-2005 Hewlett-Packard Co Contributed by David Mosberger-Tang <davidm@hpl.hp.com> This file is part of libunwind. Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ #define UNW_LOCAL_ONLY #include <setjmp.h> #include "libunwind_i.h" #include "jmpbuf.h" #include "setjmp_i.h" #if !defined(_NSIG) && defined(_SIG_MAXSIG) # define _NSIG (_SIG_MAXSIG - 1) #endif #if defined(__GLIBC__) #if __GLIBC_PREREQ(2, 4) /* Starting with glibc-2.4, {sig,}setjmp in GLIBC obfuscates the register values in jmp_buf by XORing them with a "random" canary value. This makes it impossible to implement longjmp, as we can never match wp[JB_SP], unless we decode the canary first. Doing so is possible, but doesn't appear to be worth the trouble, so we simply defer to glibc siglongjmp here. */ #define siglongjmp __nonworking_siglongjmp static void siglongjmp (sigjmp_buf env, int val) UNUSED; #endif #endif /* __GLIBC_PREREQ */ void siglongjmp (sigjmp_buf env, int val) { unw_word_t *wp = (unw_word_t *) env; extern int _UI_siglongjmp_cont; extern int _UI_longjmp_cont; unw_context_t uc; unw_cursor_t c; unw_word_t sp; int *cont; if (unw_getcontext (&uc) < 0 || unw_init_local (&c, &uc) < 0) abort (); do { if (unw_get_reg (&c, UNW_REG_SP, &sp) < 0) abort (); #ifdef __FreeBSD__ if (sp != wp[JB_SP] + sizeof(unw_word_t)) #else if (sp != wp[JB_SP]) #endif continue; if (!bsp_match (&c, wp)) continue; /* found the right frame: */ /* default to resuming without restoring signal-mask */ cont = &_UI_longjmp_cont; /* Order of evaluation is important here: if unw_resume() restores signal mask, we must set it up appropriately, even if wp[JB_MASK_SAVED] is FALSE. */ if (!resume_restores_sigmask (&c, wp) && wp[JB_MASK_SAVED]) { /* sigmask was saved */ #if defined(__linux__) if (UNW_NUM_EH_REGS < 4 || _NSIG > 16 * sizeof (unw_word_t)) /* signal mask doesn't fit into EH arguments and we can't put it on the stack without overwriting something else... */ abort (); else if (unw_set_reg (&c, UNW_REG_EH + 2, wp[JB_MASK]) < 0 || (_NSIG > 8 * sizeof (unw_word_t) && unw_set_reg (&c, UNW_REG_EH + 3, wp[JB_MASK + 1]) < 0)) abort (); #elif defined(__FreeBSD__) if (unw_set_reg (&c, UNW_REG_EH + 2, &wp[JB_MASK]) < 0) abort(); #else #error Port me #endif cont = &_UI_siglongjmp_cont; } if (unw_set_reg (&c, UNW_REG_EH + 0, wp[JB_RP]) < 0 || unw_set_reg (&c, UNW_REG_EH + 1, val) < 0 || unw_set_reg (&c, UNW_REG_IP, (unw_word_t) (uintptr_t) cont)) abort (); unw_resume (&c); abort (); } while (unw_step (&c) > 0); abort (); }