void _dump_crash_report(unsigne pid)
// shortened code from android's debuggerd
// to get a backtrace on ARM
{
unw_addr_space_t as;
struct UPT_info *ui;
unw_cursor_t cursor;
as = unw_create_addr_space(&_UPT_accessors, 0);
ui = _UPT_create(pid);
int ret = unw_init_remote(&cursor, as, ui);
if (ret < 0) {
PRINTF("WARNING: unw_init_remote() failed [pid %i]\n", pid);
_UPT_destroy(ui);
return;
}
PRINTF("DEBUG: backtrace of the remote process (pid %d) using libunwind-ptrace:\n", pid);
do {
unw_word_t ip, sp, offp;
char buf[512];
unw_get_reg(&cursor, UNW_REG_IP, &ip);
unw_get_reg(&cursor, UNW_REG_SP, &sp);
unw_get_proc_name(&cursor, buf, sizeof (buf), &offp);
PRINTF("DEBUG: ip: %10p, sp: %10p %s\n", (void*) ip, (void*) sp, buf);
} while ((ret = unw_step (&cursor)) > 0);
_UPT_destroy (ui);
}
static void
destroy_unwind(struct Process *proc)
{
#if defined(HAVE_LIBUNWIND)
_UPT_destroy(proc->unwind_priv);
unw_destroy_addr_space(proc->unwind_as);
#endif /* defined(HAVE_LIBUNWIND) */
}
int backtrace_ptrace(int pid, int *tids, int *index, int nr_tids)
{
#if !defined (NO_LIBUNWIND_PTRACE)
int i, count, rc = 0;
int *threads = NULL;
count = get_threads(pid, &threads);
if (!count || threads == NULL)
return -1;
if (tids != NULL) {
if (adjust_threads(threads, count, tids, index, nr_tids) < 0)
return -1;
free(threads);
count = nr_tids;
threads = tids;
}
if (attach_process(pid) < 0)
return -1;
for (i = 0; i < count; ++i) {
void *upt_info;
printf("-------------------- thread %d (%d) --------------------\n",
(index != NULL ? index[i] : i+1), threads[i]);
if (threads[i] != pid && attach_thread(threads[i]) < 0) {
rc = -1;
break;
}
upt_info = _UPT_create(threads[i]);
if (backtrace_thread(&_UPT_accessors, upt_info) < 0)
rc = -1;
_UPT_destroy(upt_info);
if (threads[i] != pid && detach_thread(threads[i]))
rc = -1;
if (rc < 0)
break;
}
free(threads);
if (detach_process(pid) < 0)
return -1;
return rc;
#else
return -1;
#endif /* NO_LIBUNWIND_PTRACE */
}
UnwindPtrace::~UnwindPtrace() {
if (upt_info_) {
_UPT_destroy(upt_info_);
upt_info_ = NULL;
}
if (addr_space_) {
unw_destroy_addr_space(addr_space_);
addr_space_ = NULL;
}
}
size_t arch_unwindStack(pid_t pid, funcs_t * funcs)
{
size_t num_frames = 0, mapsCnt = 0;
procMap_t *mapsList = arch_parsePidMaps(pid, &mapsCnt);
defer {
free(mapsList);
};
unw_addr_space_t as = unw_create_addr_space(&_UPT_accessors, __BYTE_ORDER);
if (!as) {
LOG_E("[pid='%d'] unw_create_addr_space failed", pid);
return num_frames;
}
defer {
unw_destroy_addr_space(as);
};
void *ui = _UPT_create(pid);
if (ui == NULL) {
LOG_E("[pid='%d'] _UPT_create failed", pid);
return num_frames;
}
defer {
_UPT_destroy(ui);
};
unw_cursor_t c;
int ret = unw_init_remote(&c, as, ui);
if (ret < 0) {
LOG_E("[pid='%d'] unw_init_remote failed (%s)", pid, UNW_ER[-ret]);
return num_frames;
}
for (num_frames = 0; unw_step(&c) > 0 && num_frames < _HF_MAX_FUNCS; num_frames++) {
unw_word_t ip;
char *mapName = NULL;
ret = unw_get_reg(&c, UNW_REG_IP, &ip);
if (ret < 0) {
LOG_E("[pid='%d'] [%zd] failed to read IP (%s)", pid, num_frames, UNW_ER[-ret]);
funcs[num_frames].pc = 0;
} else {
funcs[num_frames].pc = (void *)ip;
}
if (mapsCnt > 0 && (mapName = arch_searchMaps(ip, mapsCnt, mapsList)) != NULL) {
memcpy(funcs[num_frames].mapName, mapName, sizeof(funcs[num_frames].mapName));
} else {
strncpy(funcs[num_frames].mapName, "UNKNOWN", sizeof(funcs[num_frames].mapName));
}
}
return num_frames;
}
UnwindPtrace::~UnwindPtrace() {
if (upt_info_) {
_UPT_destroy(upt_info_);
upt_info_ = NULL;
}
if (addr_space_) {
// Remove the map from the address space before destroying it.
// It will be freed in the UnwindMap destructor.
unw_map_set(addr_space_, NULL);
unw_destroy_addr_space(addr_space_);
addr_space_ = NULL;
}
}
BOOL PAL_VirtualUnwindOutOfProc(CONTEXT *context,
KNONVOLATILE_CONTEXT_POINTERS *contextPointers,
DWORD pid,
ReadMemoryWordCallback readMemCallback)
{
// This function can be executed only by one thread at a time.
// The reason for this is that we need to pass context and read mem function to libunwind callbacks
// but "arg" is already used by the pointer returned from _UPT_create().
// So we resort to using global variables and a lock.
struct Lock
{
CRITICAL_SECTION cs;
Lock()
{
// ctor of a static variable is a thread-safe way to initialize critical section exactly once (clang,gcc)
InitializeCriticalSection(&cs);
}
};
struct LockHolder
{
CRITICAL_SECTION *cs;
LockHolder(CRITICAL_SECTION *cs)
{
this->cs = cs;
EnterCriticalSection(cs);
}
~LockHolder()
{
LeaveCriticalSection(cs);
cs = NULL;
}
};
static Lock lock;
LockHolder lockHolder(&lock.cs);
int st;
unw_context_t unwContext;
unw_cursor_t cursor;
unw_addr_space_t addrSpace = 0;
void *libunwindUptPtr = NULL;
BOOL result = FALSE;
LibunwindCallbacksInfo.Context = context;
LibunwindCallbacksInfo.readMemCallback = readMemCallback;
WinContextToUnwindContext(context, &unwContext);
addrSpace = unw_create_addr_space(&unwind_accessors, 0);
libunwindUptPtr = _UPT_create(pid);
st = unw_init_remote(&cursor, addrSpace, libunwindUptPtr);
if (st < 0)
{
result = FALSE;
goto Exit;
}
st = unw_step(&cursor);
if (st < 0)
{
result = FALSE;
goto Exit;
}
UnwindContextToWinContext(&cursor, context);
if (contextPointers != NULL)
{
GetContextPointers(&cursor, &unwContext, contextPointers);
}
result = TRUE;
Exit:
if (libunwindUptPtr != nullptr)
{
_UPT_destroy(libunwindUptPtr);
}
if (addrSpace != 0)
{
unw_destroy_addr_space(addrSpace);
}
return result;
}
static void print_stack_trace(pid_t pid, int * count)
{
void * pinfo = NULL;
unw_addr_space_t aspace = NULL;
unw_cursor_t cursor;
unw_word_t ip, sp;
char nbuf[256];
unw_word_t off;
int ret;
if (ptrace(PTRACE_ATTACH, pid, NULL, NULL) < 0) {
fprintf(stderr,
"Failed to attach to process %llu: %s\n",
(unsigned long long)pid, strerror(errno));
return;
}
/* Wait until the attach is complete. */
waitpid(pid, NULL, 0);
if (((pinfo = _UPT_create(pid)) == NULL) ||
((aspace = unw_create_addr_space(&_UPT_accessors, 0)) == NULL)) {
/* Probably out of memory. */
fprintf(stderr,
"Unable to initialize stack unwind for process %llu\n",
(unsigned long long)pid);
goto cleanup;
}
if ((ret = unw_init_remote(&cursor, aspace, pinfo))) {
fprintf(stderr,
"Unable to unwind stack for process %llu: %s\n",
(unsigned long long)pid, unw_strerror(ret));
goto cleanup;
}
if (*count > 0) {
printf("\n");
}
if (procname(pid, nbuf, sizeof(nbuf))) {
printf("Stack trace for process %llu (%s):\n",
(unsigned long long)pid, nbuf);
} else {
printf("Stack trace for process %llu:\n",
(unsigned long long)pid);
}
while (unw_step(&cursor) > 0) {
ip = sp = off = 0;
unw_get_reg(&cursor, UNW_REG_IP, &ip);
unw_get_reg(&cursor, UNW_REG_SP, &sp);
ret = unw_get_proc_name(&cursor, nbuf, sizeof(nbuf), &off);
if (ret != 0 && ret != -UNW_ENOMEM) {
snprintf(nbuf, sizeof(nbuf), "<unknown symbol>");
}
printf(" %s + %#llx [ip=%#llx] [sp=%#llx]\n",
nbuf, (long long)off, (long long)ip,
(long long)sp);
}
(*count)++;
cleanup:
if (aspace) {
unw_destroy_addr_space(aspace);
}
if (pinfo) {
_UPT_destroy(pinfo);
}
ptrace(PTRACE_DETACH, pid, NULL, NULL);
}
bool UPTDestroyCallback::execute_real()
{
_UPT_destroy(handle_);
return true;
}
void bt_finish(struct bt_data *btd)
{
_UPT_destroy(btd->ui);
unw_destroy_addr_space(btd->as);
free(btd);
}
int
main(int argc, char **argv) {
int status, pid, pending_sig, optind = 1, state = 1;
as = unw_create_addr_space(&_UPT_accessors, 0);
if (!as)
panic ("unw_create_addr_space() failed");
if (argc == 1) {
static char *args[] = {"self", "/bin/ls", "/usr", NULL};
/* automated test case */
argv = args;
}
else if (argc > 1)
while (argv[optind][0] == '-') {
if (strcmp(argv[optind], "-v") == 0)
++optind, verbose = 1;
else if (strcmp(argv[optind], "-i") == 0)
++optind, trace_mode = INSTRUCTION; /* backtrace at each insn */
else if (strcmp(argv[optind], "-s") == 0)
++optind, trace_mode = SYSCALL; /* backtrace at each syscall */
else if (strcmp(argv[optind], "-t") == 0)
/* Execute until raise(SIGUSR1), then backtrace at each insn
until raise(SIGUSR2). */
++optind, trace_mode = TRIGGER;
else if (strcmp(argv[optind], "-c") == 0)
/* Enable caching of unwind-info. */
++optind, unw_set_caching_policy(as, UNW_CACHE_GLOBAL);
else if (strcmp(argv[optind], "-n") == 0)
/* Don't look-up and print symbol names. */
++optind, print_names = 0;
else
fprintf(stderr, "unrecognized option: %s\n", argv[optind++]);
if (optind >= argc)
break;
}
target_pid = fork();
if (!target_pid) {
/* child */
if (!verbose)
dup2(open("/dev/null", O_WRONLY), 1);
ptrace(PTRACE_TRACEME, 0, 0, 0);
if ((argc > 1) && (optind == argc)) {
fprintf(stderr, "Need to specify a command line for the child\n");
exit(-1);
}
execve(argv[optind], argv + optind, environ);
_exit(-1);
}
atexit(target_pid_kill);
ui = _UPT_create(target_pid);
while (nerrors <= nerrors_max) {
pid = wait4(-1, &status, 0, NULL);
if (pid == -1) {
if (errno == EINTR)
continue;
panic ("wait4() failed (errno=%d)\n", errno);
}
pending_sig = 0;
if (WIFSIGNALED (status) || WIFEXITED (status)
|| (WIFSTOPPED (status) && WSTOPSIG (status) != SIGTRAP)) {
if (WIFEXITED (status)) {
if (WEXITSTATUS (status) != 0)
panic ("child's exit status %d\n", WEXITSTATUS(status));
break;
}
else if (WIFSIGNALED (status)) {
if (!killed)
panic ("child terminated by signal %d\n", WTERMSIG(status));
break;
}
else {
pending_sig = WSTOPSIG (status);
/* Avoid deadlock: */
if (WSTOPSIG (status) == SIGKILL)
break;
if (trace_mode == TRIGGER) {
if (WSTOPSIG (status) == SIGUSR1)
state = 0;
else if (WSTOPSIG (status) == SIGUSR2)
state = 1;
}
if (WSTOPSIG (status) != SIGUSR1 && WSTOPSIG (status) != SIGUSR2) {
static int count = 0;
if (count++ > 100) {
panic ("Too many child unexpected signals (now %d)\n",
WSTOPSIG(status));
killed = 1;
}
}
}
}
switch (trace_mode) {
case TRIGGER:
if (state)
ptrace(PTRACE_CONT, target_pid, 0, 0);
else {
do_backtrace();
if (ptrace(PTRACE_SINGLESTEP, target_pid, 0, pending_sig) < 0) {
panic ("ptrace(PTRACE_SINGLESTEP) failed (errno=%d)\n", errno);
killed = 1;
}
}
break;
case SYSCALL:
if (!state)
do_backtrace();
state ^= 1;
ptrace(PTRACE_SYSCALL, target_pid, 0, pending_sig);
break;
case INSTRUCTION:
do_backtrace();
ptrace(PTRACE_SINGLESTEP, target_pid, 0, pending_sig);
break;
}
if (killed)
kill(target_pid, SIGKILL);
}
_UPT_destroy(ui);
unw_destroy_addr_space(as);
if (nerrors) {
printf("FAILURE: detected %d errors\n", nerrors);
exit(-1);
}
if (verbose)
printf("SUCCESS\n");
return 0;
}
/* Benefit from maps being sorted by address */
if (addr < mapsList[i].start) {
break;
}
}
return NULL;
}
#ifndef __ANDROID__
size_t arch_unwindStack(pid_t pid, funcs_t * funcs)
{
size_t num_frames = 0, mapsCnt = 0;
procMap_t *mapsList = arch_parsePidMaps(pid, &mapsCnt);
defer {
free(mapsList);
};
unw_addr_space_t as = unw_create_addr_space(&_UPT_accessors, __BYTE_ORDER);
if (!as) {
LOG_E("[pid='%d'] unw_create_addr_space failed", pid);
return num_frames;
}
defer {
unw_destroy_addr_space(as);
};
void *ui = _UPT_create(pid);
if (ui == NULL) {
LOG_E("[pid='%d'] _UPT_create failed", pid);
return num_frames;
}
defer {
_UPT_destroy(ui);
};
unw_cursor_t c;
int ret = unw_init_remote(&c, as, ui);
if (ret < 0) {
LOG_E("[pid='%d'] unw_init_remote failed (%s)", pid, UNW_ER[-ret]);
return num_frames;
}
for (num_frames = 0; unw_step(&c) > 0 && num_frames < _HF_MAX_FUNCS; num_frames++) {
unw_word_t ip;
char *mapName = NULL;
ret = unw_get_reg(&c, UNW_REG_IP, &ip);
if (ret < 0) {
LOG_E("[pid='%d'] [%zd] failed to read IP (%s)", pid, num_frames, UNW_ER[-ret]);
funcs[num_frames].pc = 0;
} else {
funcs[num_frames].pc = (void *)ip;
}
if (mapsCnt > 0 && (mapName = arch_searchMaps(ip, mapsCnt, mapsList)) != NULL) {
memcpy(funcs[num_frames].mapName, mapName, sizeof(funcs[num_frames].mapName));
} else {
strncpy(funcs[num_frames].mapName, "UNKNOWN", sizeof(funcs[num_frames].mapName));
}
}
return num_frames;
}
#else /* !defined(__ANDROID__) */
size_t arch_unwindStack(pid_t pid, funcs_t * funcs)
{
size_t num_frames = 0, mapsCnt = 0;
procMap_t *mapsList = arch_parsePidMaps(pid, &mapsCnt);
defer {
free(mapsList);
}
unw_addr_space_t as = unw_create_addr_space(&_UPT_accessors, __BYTE_ORDER);
if (!as) {
LOG_E("[pid='%d'] unw_create_addr_space failed", pid);
return num_frames;
}
defer {
unw_destroy_addr_space(as);
};
struct UPT_info *ui = (struct UPT_info *)_UPT_create(pid);
if (ui == NULL) {
LOG_E("[pid='%d'] _UPT_create failed", pid);
return num_frames;
}
defer {
_UPT_destroy(ui);
};
unw_cursor_t cursor;
int ret = unw_init_remote(&cursor, as, ui);
if (ret < 0) {
LOG_E("[pid='%d'] unw_init_remote failed (%s)", pid, UNW_ER[-ret]);
return num_frames;
}
do {
char *mapName = NULL;
unw_word_t pc = 0, offset = 0;
char buf[_HF_FUNC_NAME_SZ] = { 0 };
ret = unw_get_reg(&cursor, UNW_REG_IP, &pc);
if (ret < 0) {
LOG_E("[pid='%d'] [%zd] failed to read IP (%s)", pid, num_frames, UNW_ER[-ret]);
// We don't want to try to extract info from an arbitrary IP
// TODO: Maybe abort completely (goto out))
goto skip_frame_info;
}
unw_proc_info_t frameInfo;
ret = unw_get_proc_info(&cursor, &frameInfo);
if (ret < 0) {
LOG_D("[pid='%d'] [%zd] unw_get_proc_info (%s)", pid, num_frames, UNW_ER[-ret]);
// Not safe to keep parsing frameInfo
goto skip_frame_info;
}
ret = unw_get_proc_name(&cursor, buf, sizeof(buf), &offset);
if (ret < 0) {
LOG_D("[pid='%d'] [%zd] unw_get_proc_name() failed (%s)", pid, num_frames,
UNW_ER[-ret]);
buf[0] = '\0';
}
skip_frame_info:
// Compared to bfd, line var plays the role of offset from func_name
// Reports format is adjusted accordingly to reflect in saved file
funcs[num_frames].line = offset;
funcs[num_frames].pc = (void *)pc;
memcpy(funcs[num_frames].func, buf, sizeof(funcs[num_frames].func));
if (mapsCnt > 0 && (mapName = arch_searchMaps(pc, mapsCnt, mapsList)) != NULL) {
memcpy(funcs[num_frames].mapName, mapName, sizeof(funcs[num_frames].mapName));
} else {
strncpy(funcs[num_frames].mapName, "UNKNOWN", sizeof(funcs[num_frames].mapName));
}
num_frames++;
ret = unw_step(&cursor);
} while (ret > 0 && num_frames < _HF_MAX_FUNCS);
return num_frames;
}
int backtrace_ptrace(int pid, int *tids, int *index, int nr_tids)
{
#if !defined (NO_LIBUNWIND_PTRACE)
int i, count, rc = 0;
int *threads = NULL;
count = get_threads(pid, &threads);
if (!count || threads == NULL)
return -1;
if (tids != NULL) {
if (adjust_threads(threads, count, tids, index, nr_tids) < 0)
return -1;
free(threads);
count = nr_tids;
threads = tids;
}
if (attach_process(pid) < 0)
return -1;
for (i = 0; i < count; ++i) {
void *upt_info;
int x;
char comm[16];
char end_pad[25] = "------------------------";
x = get_thread_comm(threads[i], comm, sizeof(comm));
if (x > 0 && x <= sizeof(end_pad))
{
end_pad[sizeof(end_pad) - x] = '\0';
printf("-------------- thread %d (%d) (%s) %s\n", (index != NULL ? index[i] : i + 1), threads[i], comm, end_pad);
}
if (threads[i] != pid && attach_thread(threads[i]) < 0) {
rc = -1;
break;
}
upt_info = _UPT_create(threads[i]);
if (backtrace_thread(&_UPT_accessors, upt_info) < 0)
rc = -1;
_UPT_destroy(upt_info);
if (threads[i] != pid && detach_thread(threads[i]))
rc = -1;
if (rc < 0)
break;
}
free(threads);
if (detach_process(pid) < 0)
return -1;
return rc;
#else
return -1;
#endif /* NO_LIBUNWIND_PTRACE */
}
void
trace_free(ptrace_context *ctx) {
_UPT_destroy(ctx->unwind_rctx);
unw_destroy_addr_space(ctx->addr_space);
free(ctx->cmdline);
}
size_t StackCorkscrewLibunwind::Unwind (pid_t ppid, pid_t tid, size_t ignoreDepth, size_t maxDepth)
{
assert (ppid > 0);
assert (tid >= ppid);
(void) ignoreDepth;
m_frames.clear ();
if (maxDepth == 0)
{
return 0;
}
static unw_addr_space_t addr_space;
(void) addr_space;
#if UNWIND_SUPPORTED && UNWIND_REMOTE_SUPPORTED
addr_space = unw_create_addr_space (&_UPT_accessors, 0);
if (!addr_space)
{
fprintf (stderr, "unw_create_addr_space failed.\n");
fflush (stderr);
return 0;
}
#endif
#if UNWIND_MAP_SUPPORTED && UNWIND_FUNCTION_NAME
unw_map_cursor_t map_cursor;
if (unw_map_cursor_create (&map_cursor, tid) < 0)
{
fprintf (stderr, "Failed to create map cursor.\n");
fflush (stderr);
return 0;
}
unw_map_set (addr_space, &map_cursor);
#endif
#if UNWIND_REMOTE_SUPPORTED
struct UPT_info* upt_info = reinterpret_cast<struct UPT_info*> (_UPT_create (tid));
if (!upt_info)
{
fprintf (stderr, "Failed to create upt info.\n");
fflush (stderr);
return 0;
}
unw_cursor_t cursor;
{
int error = unw_init_remote (&cursor, addr_space, upt_info);
if (error < 0)
{
fprintf (stderr, "unw_init_remote failed (%d)\n", error);
fflush (stderr);
return 0;
}
}
#endif
bool shouldContinue = false;
size_t numFrames = 0;
do
{
//
// Evaluate instruction pointer / program counter address.
//
#if UNWIND_REMOTE_SUPPORTED
uint64_t pc = 0;
{
unw_word_t unwound_pc;
int error = unw_get_reg (&cursor, UNW_REG_IP, &unwound_pc);
if (error < 0)
{
fprintf (stderr, "Failed to read IP (%d)\n", error);
fflush (stderr);
break;
}
pc = unwound_pc;
}
#if UNWIND_STACK_POINTER
uint64_t sp = 0;
{
unw_word_t unwound_sp;
int error = unw_get_reg (&cursor, UNW_REG_SP, &unwound_sp);
if (error < 0)
{
fprintf (stderr, "Failed to read SP (%d)\n", error);
fflush (stderr);
break;
}
sp = unwound_sp;
}
#endif
if (ignoreDepth == 0)
{
const char *function = "??";
#if UNWIND_FUNCTION_NAME
uintptr_t offset = 0;
char buffer [128];
unw_word_t value;
const int result = unw_get_proc_name_by_ip (addr_space, pc, buffer, sizeof (buffer), &value, upt_info);
if (result >= 0 && buffer [0] != '\0')
{
function = buffer;
offset = static_cast<uintptr_t>(value);
}
#endif
StackFrame frame;
frame.m_level = numFrames;
frame.m_pc = pc;
#if UNWIND_STACK_POINTER
frame.m_sp = sp;
#endif
strncpy (frame.m_function, function, sizeof (frame.m_function));
m_frames.push_back (frame);
numFrames++;
}
else
{
ignoreDepth--;
}
shouldContinue = (unw_step (&cursor) > 0);
#endif
}
while (shouldContinue && numFrames < maxDepth);
#if UNWIND_REMOTE_SUPPORTED
_UPT_destroy (upt_info);
#endif
#if UNWIND_MAP_SUPPORTED && UNWIND_FUNCTION_NAME
unw_map_cursor_destroy (&map_cursor);
unw_map_cursor_clear (&map_cursor);
#endif
return m_frames.size ();
}