1 /*
2 * Copyright (C) 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 //
18 // Strictly to deal with reboot into system after OTA after /data
19 // mounts to pull the last pmsg file data and place it
20 // into /data/misc/recovery/ directory, rotating it in.
21 //
22 // Usage: recovery-persist [--force-persist]
23 //
24 // On systems without /cache mount, all file content representing in the
25 // recovery/ directory stored in /sys/fs/pstore/pmsg-ramoops-0 in logger
26 // format that reside in the LOG_ID_SYSTEM buffer at ANDROID_LOG_INFO
27 // priority or higher is transfered to the /data/misc/recovery/ directory.
28 // The content is matched and rotated in as need be.
29 //
30 // --force-persist ignore /cache mount, always rotate in the contents.
31 //
32
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <string.h>
36 #include <unistd.h>
37
38 #include <string>
39
40 #include <android-base/file.h>
41 #include <android-base/logging.h>
42 #include <private/android_logger.h> /* private pmsg functions */
43
44 #include "recovery_utils/logging.h"
45 #include "recovery_utils/parse_install_logs.h"
46
47 constexpr const char* LAST_LOG_FILE = "/data/misc/recovery/last_log";
48 constexpr const char* LAST_PMSG_FILE = "/sys/fs/pstore/pmsg-ramoops-0";
49 constexpr const char* LAST_KMSG_FILE = "/data/misc/recovery/last_kmsg";
50 constexpr const char* LAST_CONSOLE_FILE = "/sys/fs/pstore/console-ramoops-0";
51 constexpr const char* ALT_LAST_CONSOLE_FILE = "/sys/fs/pstore/console-ramoops";
52
53 // close a file, log an error if the error indicator is set
check_and_fclose(FILE * fp,const char * name)54 static void check_and_fclose(FILE *fp, const char *name) {
55 fflush(fp);
56 if (ferror(fp)) {
57 PLOG(ERROR) << "Error in " << name;
58 }
59 fclose(fp);
60 }
61
copy_file(const char * source,const char * destination)62 static void copy_file(const char* source, const char* destination) {
63 FILE* dest_fp = fopen(destination, "we");
64 if (dest_fp == nullptr) {
65 PLOG(ERROR) << "Can't open " << destination;
66 } else {
67 FILE* source_fp = fopen(source, "re");
68 if (source_fp != nullptr) {
69 char buf[4096];
70 size_t bytes;
71 while ((bytes = fread(buf, 1, sizeof(buf), source_fp)) != 0) {
72 fwrite(buf, 1, bytes, dest_fp);
73 }
74 check_and_fclose(source_fp, source);
75 }
76 check_and_fclose(dest_fp, destination);
77 }
78 }
79
80 static bool rotated = false;
81
logsave(log_id_t,char,const char * filename,const char * buf,size_t len,void *)82 ssize_t logsave(
83 log_id_t /* logId */,
84 char /* prio */,
85 const char *filename,
86 const char *buf, size_t len,
87 void * /* arg */) {
88
89 std::string destination("/data/misc/");
90 destination += filename;
91
92 std::string buffer(buf, len);
93
94 {
95 std::string content;
96 android::base::ReadFileToString(destination, &content);
97
98 if (buffer.compare(content) == 0) {
99 return len;
100 }
101 }
102
103 // ToDo: Any others that match? Are we pulling in multiple
104 // already-rotated files? Algorithm thus far is KISS: one file,
105 // one rotation allowed.
106
107 rotate_logs(LAST_LOG_FILE, LAST_KMSG_FILE);
108 rotated = true;
109
110 return android::base::WriteStringToFile(buffer, destination.c_str());
111 }
112
main(int argc,char ** argv)113 int main(int argc, char **argv) {
114
115 /* Is /cache a mount?, we have been delivered where we are not wanted */
116 /*
117 * Following code halves the size of the executable as compared to:
118 *
119 * load_volume_table();
120 * has_cache = volume_for_path(CACHE_ROOT) != nullptr;
121 */
122 bool has_cache = false;
123 static const char mounts_file[] = "/proc/mounts";
124 FILE* fp = fopen(mounts_file, "re");
125 if (!fp) {
126 PLOG(ERROR) << "failed to open " << mounts_file;
127 } else {
128 char *line = NULL;
129 size_t len = 0;
130 ssize_t read;
131 while ((read = getline(&line, &len, fp)) != -1) {
132 if (strstr(line, " /cache ")) {
133 has_cache = true;
134 break;
135 }
136 }
137 free(line);
138 fclose(fp);
139 }
140
141 if (has_cache) {
142 // Collects and reports the non-a/b update metrics from last_install; and removes the file
143 // to avoid duplicate report.
144 if (access(LAST_INSTALL_FILE_IN_CACHE, F_OK) && unlink(LAST_INSTALL_FILE_IN_CACHE) == -1) {
145 PLOG(ERROR) << "Failed to unlink " << LAST_INSTALL_FILE_IN_CACHE;
146 }
147
148 // TBD: Future location to move content from /cache/recovery to /data/misc/recovery/
149 // if --force-persist flag, then transfer pmsg data anyways
150 if ((argc <= 1) || !argv[1] || strcmp(argv[1], "--force-persist")) {
151 return 0;
152 }
153 }
154
155 /* Is there something in pmsg? */
156 if (access(LAST_PMSG_FILE, R_OK)) {
157 return 0;
158 }
159
160 // Take last pmsg file contents and send it off to the logsave
161 __android_log_pmsg_file_read(
162 LOG_ID_SYSTEM, ANDROID_LOG_INFO, "recovery/", logsave, NULL);
163
164 // For those device without /cache, the last_install file has been copied to
165 // /data/misc/recovery from pmsg. Looks for the sideload history only.
166 if (!has_cache) {
167 if (access(LAST_INSTALL_FILE, F_OK) && unlink(LAST_INSTALL_FILE) == -1) {
168 PLOG(ERROR) << "Failed to unlink " << LAST_INSTALL_FILE;
169 }
170 }
171
172 /* Is there a last console log too? */
173 if (rotated) {
174 if (!access(LAST_CONSOLE_FILE, R_OK)) {
175 copy_file(LAST_CONSOLE_FILE, LAST_KMSG_FILE);
176 } else if (!access(ALT_LAST_CONSOLE_FILE, R_OK)) {
177 copy_file(ALT_LAST_CONSOLE_FILE, LAST_KMSG_FILE);
178 }
179 }
180
181 return 0;
182 }
183