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 <stdbool.h>
18 #include <fcntl.h>
19 #include <stdio.h>
20 #include <stdlib.h>
21 #include <string.h>
22 #include <sys/types.h>
23 #include <sys/socket.h>
24 #include <unistd.h>
25 
26 #include <cutils/debugger.h>
27 #include <cutils/sockets.h>
28 
29 #define LOG_TAG "DEBUG"
30 #include <log/log.h>
31 
send_request(int sock_fd,void * msg_ptr,size_t msg_len)32 static int send_request(int sock_fd, void* msg_ptr, size_t msg_len) {
33   int result = 0;
34   if (TEMP_FAILURE_RETRY(write(sock_fd, msg_ptr, msg_len)) != (ssize_t) msg_len) {
35     result = -1;
36   } else {
37     char ack;
38     if (TEMP_FAILURE_RETRY(read(sock_fd, &ack, 1)) != 1) {
39       result = -1;
40     }
41   }
42   return result;
43 }
44 
make_dump_request(debugger_action_t action,pid_t tid,int timeout_secs)45 static int make_dump_request(debugger_action_t action, pid_t tid, int timeout_secs) {
46   debugger_msg_t msg;
47   memset(&msg, 0, sizeof(msg));
48   msg.tid = tid;
49   msg.action = action;
50 
51   int sock_fd = socket_local_client(DEBUGGER_SOCKET_NAME, ANDROID_SOCKET_NAMESPACE_ABSTRACT,
52       SOCK_STREAM | SOCK_CLOEXEC);
53   if (sock_fd < 0) {
54     return -1;
55   }
56 
57   if (timeout_secs > 0) {
58     struct timeval tm;
59     tm.tv_sec = timeout_secs;
60     tm.tv_usec = 0;
61     if (setsockopt(sock_fd, SOL_SOCKET, SO_RCVTIMEO, &tm, sizeof(tm)) == -1) {
62       ALOGE("WARNING: Cannot set receive timeout value on socket: %s", strerror(errno));
63     }
64 
65     if (setsockopt(sock_fd, SOL_SOCKET, SO_SNDTIMEO, &tm, sizeof(tm)) == -1) {
66       ALOGE("WARNING: Cannot set send timeout value on socket: %s", strerror(errno));
67     }
68   }
69 
70   if (send_request(sock_fd, &msg, sizeof(msg)) < 0) {
71     close(sock_fd);
72     return -1;
73   }
74 
75   return sock_fd;
76 }
77 
dump_backtrace_to_file(pid_t tid,int fd)78 int dump_backtrace_to_file(pid_t tid, int fd) {
79   return dump_backtrace_to_file_timeout(tid, fd, 0);
80 }
81 
dump_backtrace_to_file_timeout(pid_t tid,int fd,int timeout_secs)82 int dump_backtrace_to_file_timeout(pid_t tid, int fd, int timeout_secs) {
83   int sock_fd = make_dump_request(DEBUGGER_ACTION_DUMP_BACKTRACE, tid, timeout_secs);
84   if (sock_fd < 0) {
85     return -1;
86   }
87 
88   /* Write the data read from the socket to the fd. */
89   int result = 0;
90   char buffer[1024];
91   ssize_t n;
92   while ((n = TEMP_FAILURE_RETRY(read(sock_fd, buffer, sizeof(buffer)))) > 0) {
93     if (TEMP_FAILURE_RETRY(write(fd, buffer, n)) != n) {
94       result = -1;
95       break;
96     }
97   }
98   close(sock_fd);
99   return result;
100 }
101 
dump_tombstone(pid_t tid,char * pathbuf,size_t pathlen)102 int dump_tombstone(pid_t tid, char* pathbuf, size_t pathlen) {
103   return dump_tombstone_timeout(tid, pathbuf, pathlen, 0);
104 }
105 
dump_tombstone_timeout(pid_t tid,char * pathbuf,size_t pathlen,int timeout_secs)106 int dump_tombstone_timeout(pid_t tid, char* pathbuf, size_t pathlen, int timeout_secs) {
107   int sock_fd = make_dump_request(DEBUGGER_ACTION_DUMP_TOMBSTONE, tid, timeout_secs);
108   if (sock_fd < 0) {
109     return -1;
110   }
111 
112   /* Read the tombstone file name. */
113   char buffer[100]; /* This is larger than the largest tombstone path. */
114   int result = 0;
115   ssize_t n = TEMP_FAILURE_RETRY(read(sock_fd, buffer, sizeof(buffer) - 1));
116   if (n <= 0) {
117     result = -1;
118   } else {
119     if (pathbuf && pathlen) {
120       if (n >= (ssize_t) pathlen) {
121         n = pathlen - 1;
122       }
123       buffer[n] = '\0';
124       memcpy(pathbuf, buffer, n + 1);
125     }
126   }
127   close(sock_fd);
128   return result;
129 }
130