1 /*
2 * Copyright (C) 2012 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include <stddef.h>
18 #include <stdbool.h>
19 #include <stdlib.h>
20 #include <string.h>
21 #include <stdio.h>
22 #include <time.h>
23 #include <errno.h>
24 #include <limits.h>
25 #include <dirent.h>
26 #include <unistd.h>
27 #include <sys/types.h>
28 #include <sys/ptrace.h>
29
30 #include <corkscrew/backtrace.h>
31
32 #include "tombstone.h"
33 #include "utility.h"
34
35 #define STACK_DEPTH 32
36
dump_process_header(log_t * log,pid_t pid)37 static void dump_process_header(log_t* log, pid_t pid) {
38 char path[PATH_MAX];
39 char procnamebuf[1024];
40 char* procname = NULL;
41 FILE* fp;
42
43 snprintf(path, sizeof(path), "/proc/%d/cmdline", pid);
44 if ((fp = fopen(path, "r"))) {
45 procname = fgets(procnamebuf, sizeof(procnamebuf), fp);
46 fclose(fp);
47 }
48
49 time_t t = time(NULL);
50 struct tm tm;
51 localtime_r(&t, &tm);
52 char timestr[64];
53 strftime(timestr, sizeof(timestr), "%F %T", &tm);
54 _LOG(log, SCOPE_AT_FAULT, "\n\n----- pid %d at %s -----\n", pid, timestr);
55
56 if (procname) {
57 _LOG(log, SCOPE_AT_FAULT, "Cmd line: %s\n", procname);
58 }
59 }
60
dump_process_footer(log_t * log,pid_t pid)61 static void dump_process_footer(log_t* log, pid_t pid) {
62 _LOG(log, SCOPE_AT_FAULT, "\n----- end %d -----\n", pid);
63 }
64
dump_thread(log_t * log,pid_t tid,ptrace_context_t * context,bool attached,bool * detach_failed,int * total_sleep_time_usec)65 static void dump_thread(log_t* log, pid_t tid, ptrace_context_t* context, bool attached,
66 bool* detach_failed, int* total_sleep_time_usec) {
67 char path[PATH_MAX];
68 char threadnamebuf[1024];
69 char* threadname = NULL;
70 FILE* fp;
71
72 snprintf(path, sizeof(path), "/proc/%d/comm", tid);
73 if ((fp = fopen(path, "r"))) {
74 threadname = fgets(threadnamebuf, sizeof(threadnamebuf), fp);
75 fclose(fp);
76 if (threadname) {
77 size_t len = strlen(threadname);
78 if (len && threadname[len - 1] == '\n') {
79 threadname[len - 1] = '\0';
80 }
81 }
82 }
83
84 _LOG(log, SCOPE_AT_FAULT, "\n\"%s\" sysTid=%d\n",
85 threadname ? threadname : "<unknown>", tid);
86
87 if (!attached && ptrace(PTRACE_ATTACH, tid, 0, 0) < 0) {
88 _LOG(log, SCOPE_AT_FAULT, "Could not attach to thread: %s\n", strerror(errno));
89 return;
90 }
91
92 wait_for_stop(tid, total_sleep_time_usec);
93
94 backtrace_frame_t backtrace[STACK_DEPTH];
95 ssize_t frames = unwind_backtrace_ptrace(tid, context, backtrace, 0, STACK_DEPTH);
96 if (frames <= 0) {
97 _LOG(log, SCOPE_AT_FAULT, "Could not obtain stack trace for thread.\n");
98 } else {
99 backtrace_symbol_t backtrace_symbols[STACK_DEPTH];
100 get_backtrace_symbols_ptrace(context, backtrace, frames, backtrace_symbols);
101 for (size_t i = 0; i < (size_t)frames; i++) {
102 char line[MAX_BACKTRACE_LINE_LENGTH];
103 format_backtrace_line(i, &backtrace[i], &backtrace_symbols[i],
104 line, MAX_BACKTRACE_LINE_LENGTH);
105 _LOG(log, SCOPE_AT_FAULT, " %s\n", line);
106 }
107 free_backtrace_symbols(backtrace_symbols, frames);
108 }
109
110 if (!attached && ptrace(PTRACE_DETACH, tid, 0, 0) != 0) {
111 LOG("ptrace detach from %d failed: %s\n", tid, strerror(errno));
112 *detach_failed = true;
113 }
114 }
115
dump_backtrace(int fd,int amfd,pid_t pid,pid_t tid,bool * detach_failed,int * total_sleep_time_usec)116 void dump_backtrace(int fd, int amfd, pid_t pid, pid_t tid, bool* detach_failed,
117 int* total_sleep_time_usec) {
118 log_t log;
119 log.tfd = fd;
120 log.amfd = amfd;
121 log.quiet = true;
122
123 ptrace_context_t* context = load_ptrace_context(tid);
124 dump_process_header(&log, pid);
125 dump_thread(&log, tid, context, true, detach_failed, total_sleep_time_usec);
126
127 char task_path[64];
128 snprintf(task_path, sizeof(task_path), "/proc/%d/task", pid);
129 DIR* d = opendir(task_path);
130 if (d != NULL) {
131 struct dirent* de = NULL;
132 while ((de = readdir(d)) != NULL) {
133 if (!strcmp(de->d_name, ".") || !strcmp(de->d_name, "..")) {
134 continue;
135 }
136
137 char* end;
138 pid_t new_tid = strtoul(de->d_name, &end, 10);
139 if (*end || new_tid == tid) {
140 continue;
141 }
142
143 dump_thread(&log, new_tid, context, false, detach_failed, total_sleep_time_usec);
144 }
145 closedir(d);
146 }
147
148 dump_process_footer(&log, pid);
149 free_ptrace_context(context);
150 }
151