mirror of
https://github.com/jart/cosmopolitan.git
synced 2025-01-31 19:43:32 +00:00
131 lines
4.7 KiB
C
131 lines
4.7 KiB
C
/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
|
|
│ vi: set et 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 "ape/sections.internal.h"
|
|
#include "libc/atomic.h"
|
|
#include "libc/calls/blockcancel.internal.h"
|
|
#include "libc/calls/calls.h"
|
|
#include "libc/calls/syscall-sysv.internal.h"
|
|
#include "libc/cosmo.h"
|
|
#include "libc/dce.h"
|
|
#include "libc/elf/def.h"
|
|
#include "libc/elf/tinyelf.internal.h"
|
|
#include "libc/errno.h"
|
|
#include "libc/intrin/directmap.internal.h"
|
|
#include "libc/nt/memory.h"
|
|
#include "libc/nt/runtime.h"
|
|
#include "libc/runtime/runtime.h"
|
|
#include "libc/serialize.h"
|
|
#include "libc/str/str.h"
|
|
#include "libc/sysv/consts/map.h"
|
|
#include "libc/sysv/consts/o.h"
|
|
#include "libc/sysv/consts/prot.h"
|
|
|
|
static struct {
|
|
atomic_uint once;
|
|
const char *res;
|
|
char buf[PATH_MAX];
|
|
} g_comdbg;
|
|
|
|
static const char *kDbgExts[] = {
|
|
".dbg",
|
|
".com.dbg",
|
|
#ifdef __aarch64__
|
|
".aarch64.elf",
|
|
#elif defined(__powerpc64__)
|
|
".ppc64.elf",
|
|
#endif
|
|
};
|
|
|
|
static int GetElfMachine(void) {
|
|
#ifdef __x86_64__
|
|
return EM_NEXGEN32E;
|
|
#elif defined(__aarch64__)
|
|
return EM_AARCH64;
|
|
#elif defined(__powerpc64__)
|
|
return EM_PPC64;
|
|
#elif defined(__riscv)
|
|
return EM_RISCV;
|
|
#elif defined(__s390x__)
|
|
return EM_S390;
|
|
#else
|
|
#error "unsupported architecture"
|
|
#endif
|
|
}
|
|
|
|
static bool IsMyDebugBinary(const char *path) {
|
|
int64_t size;
|
|
uintptr_t value;
|
|
bool res = false;
|
|
int fd, e = errno;
|
|
struct DirectMap dm;
|
|
BLOCK_CANCELATION;
|
|
if ((fd = open(path, O_RDONLY | O_CLOEXEC, 0)) != -1) {
|
|
// sanity test that this .com.dbg file (1) is an elf image, and (2)
|
|
// contains the same number of bytes of code as our .com executable
|
|
// which is currently running in memory.
|
|
if ((size = lseek(fd, 0, SEEK_END)) != -1 &&
|
|
(dm = sys_mmap((void *)0x12345000000, size, PROT_READ, MAP_SHARED, fd,
|
|
0))
|
|
.addr != MAP_FAILED) {
|
|
if (READ32LE((char *)dm.addr) == READ32LE("\177ELF") &&
|
|
((Elf64_Ehdr *)dm.addr)->e_machine == GetElfMachine() &&
|
|
GetElfSymbolValue(dm.addr, "_etext", &value)) {
|
|
res = !_etext || value == (uintptr_t)_etext;
|
|
}
|
|
if (!IsWindows()) {
|
|
sys_munmap(dm.addr, size);
|
|
} else {
|
|
CloseHandle(dm.maphandle);
|
|
UnmapViewOfFile(dm.addr);
|
|
}
|
|
}
|
|
close(fd);
|
|
}
|
|
ALLOW_CANCELATION;
|
|
errno = e;
|
|
return res;
|
|
}
|
|
|
|
static void FindDebugBinaryInit(void) {
|
|
const char *comdbg;
|
|
if ((comdbg = getenv("COMDBG")) && IsMyDebugBinary(comdbg)) {
|
|
g_comdbg.res = comdbg;
|
|
return;
|
|
}
|
|
char *prog = GetProgramExecutableName();
|
|
for (int i = 0; i < ARRAYLEN(kDbgExts); ++i) {
|
|
strlcpy(g_comdbg.buf, prog, sizeof(g_comdbg.buf));
|
|
strlcat(g_comdbg.buf, kDbgExts[i], sizeof(g_comdbg.buf));
|
|
if (IsMyDebugBinary(g_comdbg.buf)) {
|
|
g_comdbg.res = g_comdbg.buf;
|
|
return;
|
|
}
|
|
}
|
|
g_comdbg.res = prog;
|
|
}
|
|
|
|
/**
|
|
* Returns path of binary with the debug information, or null.
|
|
*
|
|
* @return path to debug binary, or NULL
|
|
*/
|
|
const char *FindDebugBinary(void) {
|
|
cosmo_once(&g_comdbg.once, FindDebugBinaryInit);
|
|
return g_comdbg.res;
|
|
}
|