platform_system_core/debuggerd/backtrace.cpp

142 lines
4.0 KiB
C++

/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <time.h>
#include <errno.h>
#include <limits.h>
#include <dirent.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/ptrace.h>
#include <backtrace/Backtrace.h>
#include <UniquePtr.h>
#include "backtrace.h"
#include "utility.h"
static void dump_process_header(log_t* log, pid_t pid) {
char path[PATH_MAX];
char procnamebuf[1024];
char* procname = NULL;
FILE* fp;
snprintf(path, sizeof(path), "/proc/%d/cmdline", pid);
if ((fp = fopen(path, "r"))) {
procname = fgets(procnamebuf, sizeof(procnamebuf), fp);
fclose(fp);
}
time_t t = time(NULL);
struct tm tm;
localtime_r(&t, &tm);
char timestr[64];
strftime(timestr, sizeof(timestr), "%F %T", &tm);
_LOG(log, logtype::BACKTRACE, "\n\n----- pid %d at %s -----\n", pid, timestr);
if (procname) {
_LOG(log, logtype::BACKTRACE, "Cmd line: %s\n", procname);
}
_LOG(log, logtype::BACKTRACE, "ABI: '%s'\n", ABI_STRING);
}
static void dump_process_footer(log_t* log, pid_t pid) {
_LOG(log, logtype::BACKTRACE, "\n----- end %d -----\n", pid);
}
static void dump_thread(
log_t* log, pid_t tid, bool attached, bool* detach_failed, int* total_sleep_time_usec) {
char path[PATH_MAX];
char threadnamebuf[1024];
char* threadname = NULL;
FILE* fp;
snprintf(path, sizeof(path), "/proc/%d/comm", tid);
if ((fp = fopen(path, "r"))) {
threadname = fgets(threadnamebuf, sizeof(threadnamebuf), fp);
fclose(fp);
if (threadname) {
size_t len = strlen(threadname);
if (len && threadname[len - 1] == '\n') {
threadname[len - 1] = '\0';
}
}
}
_LOG(log, logtype::BACKTRACE, "\n\"%s\" sysTid=%d\n", threadname ? threadname : "<unknown>", tid);
if (!attached && ptrace(PTRACE_ATTACH, tid, 0, 0) < 0) {
_LOG(log, logtype::BACKTRACE, "Could not attach to thread: %s\n", strerror(errno));
return;
}
wait_for_stop(tid, total_sleep_time_usec);
UniquePtr<Backtrace> backtrace(Backtrace::Create(tid, BACKTRACE_CURRENT_THREAD));
if (backtrace->Unwind(0)) {
dump_backtrace_to_log(backtrace.get(), log, " ");
}
if (!attached && ptrace(PTRACE_DETACH, tid, 0, 0) != 0) {
_LOG(log, logtype::ERROR, "ptrace detach from %d failed: %s\n", tid, strerror(errno));
*detach_failed = true;
}
}
void dump_backtrace(int fd, int amfd, pid_t pid, pid_t tid, bool* detach_failed,
int* total_sleep_time_usec) {
log_t log;
log.tfd = fd;
log.amfd = amfd;
dump_process_header(&log, pid);
dump_thread(&log, tid, true, detach_failed, total_sleep_time_usec);
char task_path[64];
snprintf(task_path, sizeof(task_path), "/proc/%d/task", pid);
DIR* d = opendir(task_path);
if (d != NULL) {
struct dirent* de = NULL;
while ((de = readdir(d)) != NULL) {
if (!strcmp(de->d_name, ".") || !strcmp(de->d_name, "..")) {
continue;
}
char* end;
pid_t new_tid = strtoul(de->d_name, &end, 10);
if (*end || new_tid == tid) {
continue;
}
dump_thread(&log, new_tid, false, detach_failed, total_sleep_time_usec);
}
closedir(d);
}
dump_process_footer(&log, pid);
}
void dump_backtrace_to_log(Backtrace* backtrace, log_t* log, const char* prefix) {
for (size_t i = 0; i < backtrace->NumFrames(); i++) {
_LOG(log, logtype::BACKTRACE, "%s%s\n", prefix, backtrace->FormatFrameData(i).c_str());
}
}