cosmopolitan/libc/log/showcrashreports.c
Justine Tunney e7611a8476 Make improvements
- Get threads working on NetBSD
- Get threads working on OpenBSD
- Fix Emacs config for Emacs v28
- Improve --strace logging of sigset_t
- Improve --strace logging of struct stat
- Improve memory safety of DescribeThing functions
- Refactor auto stack allocation into LIBC_RUNTIME
- Introduce shell.com example which works on Windows
- Refactor __strace_thing into DescribeThing functions
- Document the CHECK macros and improve them in NDEBUG mode
- Rewrite MAP_STACK so it uses FreeBSD behavior across platforms
- Deprecate and discourage the use of MAP_GROWSDOWN (it's weird)
2022-05-12 06:45:36 -07:00

90 lines
4.2 KiB
C

/*-*- 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/calls/sigbits.h"
#include "libc/calls/struct/sigaction.h"
#include "libc/calls/struct/sigaltstack.h"
#include "libc/intrin/kprintf.h"
#include "libc/log/backtrace.internal.h"
#include "libc/log/internal.h"
#include "libc/log/log.h"
#include "libc/macros.internal.h"
#include "libc/runtime/symbols.internal.h"
#include "libc/sysv/consts/sa.h"
#include "libc/sysv/consts/sig.h"
#include "libc/sysv/consts/ss.h"
STATIC_YOINK("__die"); /* for backtracing */
STATIC_YOINK("malloc_inspect_all"); /* for asan memory origin */
STATIC_YOINK("__get_symbol_by_addr"); /* for asan memory origin */
extern const unsigned char __oncrash_thunks[8][11];
static void FreeSigaltstack(void *p) {
free(p);
}
/**
* 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;
struct sigaltstack ss;
/* <SYNC-LIST>: showcrashreports.c, oncrashthunks.S, oncrash.c */
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. */
/* </SYNC-LIST>: showcrashreports.c, oncrashthunks.S, oncrash.c */
bzero(&sa, sizeof(sa));
ss.ss_flags = 0;
ss.ss_size = SIGSTKSZ;
ss.ss_sp = malloc(SIGSTKSZ);
__cxa_atexit(FreeSigaltstack, ss.ss_sp, 0);
sa.sa_flags = SA_SIGINFO | SA_NODEFER | SA_ONSTACK;
sigfillset(&sa.sa_mask);
for (i = 0; i < ARRAYLEN(kCrashSigs); ++i) {
sigdelset(&sa.sa_mask, kCrashSigs[i]);
}
if (!IsWindows()) sigaltstack(&ss, 0);
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]);
}
}
GetSymbolTable();
}