1 /*
2 * Copyright (C) 2007-2016 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 <errno.h>
18 #include <fcntl.h>
19 #include <unistd.h>
20
21 #include <log/log.h>
22
23 #include "config_write.h"
24 #include "fake_log_device.h"
25 #include "log_portability.h"
26 #include "logger.h"
27
28 static int fakeOpen();
29 static void fakeClose();
30 static int fakeWrite(log_id_t log_id, struct timespec* ts, struct iovec* vec,
31 size_t nr);
32
33 static int logFds[(int)LOG_ID_MAX] = { -1, -1, -1, -1, -1, -1 };
34
35 LIBLOG_HIDDEN struct android_log_transport_write fakeLoggerWrite = {
36 .node = { &fakeLoggerWrite.node, &fakeLoggerWrite.node },
37 .context.priv = &logFds,
38 .name = "fake",
39 .available = NULL,
40 .open = fakeOpen,
41 .close = fakeClose,
42 .write = fakeWrite,
43 };
44
fakeOpen()45 static int fakeOpen() {
46 int i;
47
48 for (i = 0; i < LOG_ID_MAX; i++) {
49 /*
50 * Known maximum size string, plus an 8 character margin to deal with
51 * possible independent changes to android_log_id_to_name().
52 */
53 char buf[sizeof("/dev/log_security") + 8];
54 if (logFds[i] >= 0) {
55 continue;
56 }
57 snprintf(buf, sizeof(buf), "/dev/log_%s", android_log_id_to_name(i));
58 logFds[i] = fakeLogOpen(buf, O_WRONLY);
59 if (logFds[i] < 0) {
60 fprintf(stderr, "fakeLogOpen(%s, O_WRONLY) failed\n", buf);
61 }
62 }
63 return 0;
64 }
65
fakeClose()66 static void fakeClose() {
67 int i;
68
69 for (i = 0; i < LOG_ID_MAX; i++) {
70 fakeLogClose(logFds[i]);
71 logFds[i] = -1;
72 }
73 }
74
fakeWrite(log_id_t log_id,struct timespec * ts __unused,struct iovec * vec,size_t nr)75 static int fakeWrite(log_id_t log_id, struct timespec* ts __unused,
76 struct iovec* vec, size_t nr) {
77 ssize_t ret;
78 size_t i;
79 int logFd, len;
80
81 if (/*(int)log_id >= 0 &&*/ (int)log_id >= (int)LOG_ID_MAX) {
82 return -EINVAL;
83 }
84
85 len = 0;
86 for (i = 0; i < nr; ++i) {
87 len += vec[i].iov_len;
88 }
89
90 if (len > LOGGER_ENTRY_MAX_PAYLOAD) {
91 len = LOGGER_ENTRY_MAX_PAYLOAD;
92 }
93
94 logFd = logFds[(int)log_id];
95 ret = TEMP_FAILURE_RETRY(fakeLogWritev(logFd, vec, nr));
96 if (ret < 0) {
97 ret = -errno;
98 } else if (ret > len) {
99 ret = len;
100 }
101
102 return ret;
103 }
104