cosmopolitan/libc/log/oncrash.c

229 lines
8.1 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 │
│ │
│ This program is free software; you can redistribute it and/or modify │
│ it under the terms of the GNU General Public License as published by │
│ the Free Software Foundation; version 2 of the License. │
│ │
│ This program is distributed in the hope that it will be useful, but │
│ WITHOUT ANY WARRANTY; without even the implied warranty of │
│ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU │
│ General Public License for more details. │
│ │
│ You should have received a copy of the GNU General Public License │
│ along with this program; if not, write to the Free Software │
│ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA │
│ 02110-1301 USA │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/calls/calls.h"
#include "libc/calls/sigbits.h"
#include "libc/calls/struct/utsname.h"
#include "libc/calls/ucontext.h"
#include "libc/dce.h"
#include "libc/errno.h"
#include "libc/fmt/fmt.h"
#include "libc/log/backtrace.internal.h"
#include "libc/log/color.internal.h"
#include "libc/log/gdb.h"
#include "libc/log/internal.h"
#include "libc/log/log.h"
#include "libc/macros.h"
#include "libc/nexgen32e/stackframe.h"
#include "libc/runtime/internal.h"
#include "libc/runtime/memtrack.h"
#include "libc/runtime/runtime.h"
#include "libc/str/str.h"
#include "libc/sysv/consts/auxv.h"
#include "libc/sysv/consts/fileno.h"
#include "libc/sysv/consts/o.h"
#include "libc/sysv/consts/sig.h"
STATIC_YOINK("ftoa");
STATIC_YOINK("ntoa");
STATIC_YOINK("stoa");
/**
* @fileoverview Abnormal termination handling & GUI debugging.
* @see libc/onkill.c
*/
struct siginfo;
static const char kGregOrder[17] forcealign(1) = {
13, 11, 8, 14, 12, 9, 10, 15, 16, 0, 1, 2, 3, 4, 5, 6, 7,
};
static const char kGregNames[17][4] forcealign(1) = {
"R8", "R9", "R10", "R11", "R12", "R13", "R14", "R15", "RDI",
"RSI", "RBP", "RBX", "RDX", "RAX", "RCX", "RSP", "RIP",
};
static const char kGodHatesFlags[12] forcealign(1) = "CVPRAKZSTIDO";
static const char kCrashSigNames[8][5] forcealign(1) = {
"QUIT", "FPE", "ILL", "SEGV", "TRAP", "ABRT", "BUS"};
int kCrashSigs[8];
struct sigaction g_oldcrashacts[8];
relegated static const char *TinyStrSignal(int sig) {
size_t i;
for (i = 0; i < ARRAYLEN(kCrashSigs); ++i) {
if (kCrashSigs[i] && sig == kCrashSigs[i]) {
return kCrashSigNames[i];
}
}
return "???";
}
relegated static void ShowFunctionCalls(int fd, ucontext_t *ctx) {
struct StackFrame *bp;
struct StackFrame goodframe;
write(fd, "\r\n", 2);
if (ctx && ctx->uc_mcontext.rip && ctx->uc_mcontext.rbp) {
goodframe.next = (struct StackFrame *)ctx->uc_mcontext.rbp;
goodframe.addr = ctx->uc_mcontext.rip;
bp = &goodframe;
ShowBacktrace(fd, bp);
}
}
relegated static void DescribeCpuFlags(int fd, unsigned flags) {
unsigned i;
char buf[64], *p;
p = buf;
for (i = 0; i < ARRAYLEN(kGodHatesFlags); ++i) {
if (flags & 1) {
*p++ = ' ';
*p++ = kGodHatesFlags[i];
*p++ = 'F';
}
flags >>= 1;
}
p = stpcpy(p, " IOPL");
*p++ = '0' + (flags & 3);
write(fd, buf, p - buf);
}
relegated static void ShowGeneralRegisters(int fd, ucontext_t *ctx) {
size_t i, j, k;
long double st;
write(fd, "\r\n", 2);
for (i = 0, j = 0, k = 0; i < ARRAYLEN(kGregNames); ++i) {
if (j > 0) write(fd, " ", 1);
(dprintf)(fd, "%-3s %016lx", kGregNames[(unsigned)kGregOrder[i]],
ctx->uc_mcontext.gregs[(unsigned)kGregOrder[i]]);
if (++j == 3) {
j = 0;
memcpy(&st, (char *)&ctx->fpustate.st[k], sizeof(st));
(dprintf)(fd, " %s(%zu) %Lf", "ST", k, st);
++k;
write(fd, "\r\n", 2);
}
}
DescribeCpuFlags(fd, ctx->uc_mcontext.gregs[REG_EFL]);
}
relegated static void ShowSseRegisters(int fd, ucontext_t *ctx) {
size_t i;
write(fd, "\r\n\r\n", 4);
for (i = 0; i < 8; ++i) {
(dprintf)(fd, VEIL("r", "%s%-2zu %016lx%016lx %s%-2d %016lx%016lx\r\n"),
"XMM", i + 0, ctx->fpustate.xmm[i + 0].u64[0],
ctx->fpustate.xmm[i + 0].u64[1], "XMM", i + 8,
ctx->fpustate.xmm[i + 8].u64[0], ctx->fpustate.xmm[i + 8].u64[1]);
}
}
relegated static void ShowMemoryMappings(int outfd) {
ssize_t rc;
int c, infd;
char buf[64];
if (!IsTiny()) {
PrintMemoryIntervals(outfd, &_mmi);
if ((infd = open("/proc/self/maps", O_RDONLY)) != -1) {
while ((rc = read(infd, buf, sizeof(buf))) > 0) {
write(outfd, buf, rc);
}
}
close(infd);
}
}
relegated static void ShowCrashReport(int err, int fd, int sig,
ucontext_t *ctx) {
int i;
struct utsname names;
(dprintf)(fd, VEIL("r", "\r\n%serror%s: Uncaught SIG%s\r\n %s\r\n %s\r\n"),
RED2, RESET, TinyStrSignal(sig), getauxval(AT_EXECFN),
strerror(err));
if (uname(&names) != -1) {
(dprintf)(fd, VEIL("r", " %s %s %s %s\r\n"), names.sysname, names.nodename,
names.release, names.version);
}
ShowFunctionCalls(fd, ctx);
if (ctx) {
ShowGeneralRegisters(fd, ctx);
ShowSseRegisters(fd, ctx);
}
write(fd, "\r\n", 2);
ShowMemoryMappings(fd);
write(fd, "\r\n", 2);
for (i = 0; i < g_argc; ++i) {
write(fd, g_argv[i], strlen(g_argv[i]));
write(fd, "\r\n", 2);
}
}
relegated static void RestoreDefaultCrashSignalHandlers(void) {
size_t i;
sigset_t ss;
sigemptyset(&ss);
sigprocmask(SIG_SETMASK, &ss, NULL);
for (i = 0; i < ARRAYLEN(kCrashSigs); ++i) {
if (kCrashSigs[i]) sigaction(kCrashSigs[i], &g_oldcrashacts[i], NULL);
}
}
/**
* Crashes in a developer-friendly human-centric way.
*
* We first try to launch GDB if it's an interactive development
* session. Otherwise we show a really good crash report, sort of like
* Python, that includes filenames and line numbers. Many editors, e.g.
* Emacs, will even recognize its syntax for quick hopping to the
* failing line. That's only possible if the the .com.dbg file is in the
* same folder. If the concomitant debug binary can't be found, we
* simply print addresses which may be cross-referenced using objdump.
*
* This function never returns, except for traps w/ human supervision.
*/
relegated void __oncrash(int sig, struct siginfo *si, ucontext_t *ctx) {
intptr_t rip;
int gdbpid, err;
static bool once;
err = errno;
if (once) abort();
once = true;
/* TODO(jart): Needs translation for ucontext_t and possibly siginfo_t. */
if (IsFreebsd() || IsOpenbsd()) ctx = NULL;
rip = ctx ? ctx->uc_mcontext.rip : 0;
if ((gdbpid = IsDebuggerPresent(true))) {
DebugBreak();
} else if (isterminalinarticulate() || isrunningundermake()) {
gdbpid = -1;
} else {
RestoreDefaultCrashSignalHandlers();
gdbpid =
attachdebugger(((sig == SIGTRAP || sig == SIGQUIT) &&
(rip >= (intptr_t)&_base && rip < (intptr_t)&_etext))
? rip
: 0);
}
if (gdbpid > 0 && (sig == SIGTRAP || sig == SIGQUIT)) return;
ShowCrashReport(err, STDERR_FILENO, sig, ctx);
exit(128 + sig);
unreachable;
}