/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│ │vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│ ╞══════════════════════════════════════════════════════════════════════════════╡ │ Copyright 2020 Justine Alexandra Roberts Tunney │ │ │ │ Permission to use, copy, modify, and/or distribute this software for │ │ any purpose with or without fee is hereby granted, provided that the │ │ above copyright notice and this permission notice appear in all copies. │ │ │ │ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │ │ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │ │ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │ │ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │ │ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │ │ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │ │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │ │ PERFORMANCE OF THIS SOFTWARE. │ ╚─────────────────────────────────────────────────────────────────────────────*/ #include "libc/bits/bits.h" #include "libc/calls/calls.h" #include "libc/calls/sigbits.h" #include "libc/calls/typedef/sigaction_f.h" #include "libc/dce.h" #include "libc/log/internal.h" #include "libc/log/log.h" #include "libc/log/ubsan.internal.h" #include "libc/macros.internal.h" #include "libc/nt/signals.h" #include "libc/str/str.h" #include "libc/sysv/consts/sa.h" #include "libc/sysv/consts/sig.h" STATIC_YOINK("__die"); STATIC_YOINK("__ubsan_abort"); extern const unsigned char __oncrash_thunks[7][11]; /** * Installs crash signal handlers. * * Normally, only functions calling die() will print backtraces. This * function may be called at program startup to install handlers that * will display similar information, for most types of crashes. * * - Backtraces * - CPU state printout * - Automatic debugger attachment * * Another trick this function enables, is you can press CTRL+\ to open * the debugger GUI at any point while the program is running. It can be * useful, for example, if a program is caught in an infinite loop. * * @see callexitontermination() */ void showcrashreports(void) { size_t i; struct sigaction sa; /* : oncrashthunks.S */ kCrashSigs[0] = SIGQUIT; /* ctrl+\ aka ctrl+break */ kCrashSigs[1] = SIGFPE; /* 1 / 0 */ kCrashSigs[2] = SIGILL; /* illegal instruction */ kCrashSigs[3] = SIGSEGV; /* bad memory access */ kCrashSigs[4] = SIGTRAP; /* bad system call */ kCrashSigs[5] = SIGABRT; /* abort() called */ kCrashSigs[6] = SIGBUS; /* misaligned, noncanonical ptr, etc. */ /* : oncrashthunks.S */ memset(&sa, 0, sizeof(sa)); sa.sa_flags = SA_RESETHAND; sigfillset(&sa.sa_mask); for (i = 0; i < ARRAYLEN(kCrashSigs); ++i) { sigdelset(&sa.sa_mask, kCrashSigs[i]); } for (i = 0; i < ARRAYLEN(kCrashSigs); ++i) { if (kCrashSigs[i]) { sa.sa_sigaction = (sigaction_f)__oncrash_thunks[i]; sigaction(kCrashSigs[i], &sa, &g_oldcrashacts[i]); } } }