1 /* 2 * Copyright (C) 2005-2017 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 #ifndef _LIBS_LOG_LOG_READ_H 18 #define _LIBS_LOG_LOG_READ_H 19 20 /* deal with possible sys/cdefs.h conflict with fcntl.h */ 21 #ifdef __unused 22 #define __unused_defined __unused 23 #undef __unused 24 #endif 25 26 #include <fcntl.h> /* Pick up O_* macros */ 27 28 /* restore definitions from above */ 29 #ifdef __unused_defined 30 #define __unused __attribute__((__unused__)) 31 #endif 32 33 #include <stdint.h> 34 35 #include <log/log_id.h> 36 #include <log/log_time.h> 37 38 #ifdef __cplusplus 39 extern "C" { 40 #endif 41 42 /* 43 * Native log reading interface section. See logcat for sample code. 44 * 45 * The preferred API is an exec of logcat. Likely uses of this interface 46 * are if native code suffers from exec or filtration being too costly, 47 * access to raw information, or parsing is an issue. 48 */ 49 50 /* 51 * The userspace structure for version 1 of the logger_entry ABI. 52 */ 53 #ifndef __struct_logger_entry_defined 54 #define __struct_logger_entry_defined 55 struct logger_entry { 56 uint16_t len; /* length of the payload */ 57 uint16_t __pad; /* no matter what, we get 2 bytes of padding */ 58 int32_t pid; /* generating process's pid */ 59 int32_t tid; /* generating process's tid */ 60 int32_t sec; /* seconds since Epoch */ 61 int32_t nsec; /* nanoseconds */ 62 #ifndef __cplusplus 63 char msg[0]; /* the entry's payload */ 64 #endif 65 }; 66 #endif 67 68 /* 69 * The userspace structure for version 2 of the logger_entry ABI. 70 */ 71 #ifndef __struct_logger_entry_v2_defined 72 #define __struct_logger_entry_v2_defined 73 struct logger_entry_v2 { 74 uint16_t len; /* length of the payload */ 75 uint16_t hdr_size; /* sizeof(struct logger_entry_v2) */ 76 int32_t pid; /* generating process's pid */ 77 int32_t tid; /* generating process's tid */ 78 int32_t sec; /* seconds since Epoch */ 79 int32_t nsec; /* nanoseconds */ 80 uint32_t euid; /* effective UID of logger */ 81 #ifndef __cplusplus 82 char msg[0]; /* the entry's payload */ 83 #endif 84 } __attribute__((__packed__)); 85 #endif 86 87 /* 88 * The userspace structure for version 3 of the logger_entry ABI. 89 */ 90 #ifndef __struct_logger_entry_v3_defined 91 #define __struct_logger_entry_v3_defined 92 struct logger_entry_v3 { 93 uint16_t len; /* length of the payload */ 94 uint16_t hdr_size; /* sizeof(struct logger_entry_v3) */ 95 int32_t pid; /* generating process's pid */ 96 int32_t tid; /* generating process's tid */ 97 int32_t sec; /* seconds since Epoch */ 98 int32_t nsec; /* nanoseconds */ 99 uint32_t lid; /* log id of the payload */ 100 #ifndef __cplusplus 101 char msg[0]; /* the entry's payload */ 102 #endif 103 } __attribute__((__packed__)); 104 #endif 105 106 /* 107 * The userspace structure for version 4 of the logger_entry ABI. 108 */ 109 #ifndef __struct_logger_entry_v4_defined 110 #define __struct_logger_entry_v4_defined 111 struct logger_entry_v4 { 112 uint16_t len; /* length of the payload */ 113 uint16_t hdr_size; /* sizeof(struct logger_entry_v4) */ 114 int32_t pid; /* generating process's pid */ 115 uint32_t tid; /* generating process's tid */ 116 uint32_t sec; /* seconds since Epoch */ 117 uint32_t nsec; /* nanoseconds */ 118 uint32_t lid; /* log id of the payload, bottom 4 bits currently */ 119 uint32_t uid; /* generating process's uid */ 120 #ifndef __cplusplus 121 char msg[0]; /* the entry's payload */ 122 #endif 123 }; 124 #endif 125 126 /* 127 * The maximum size of the log entry payload that can be 128 * written to the logger. An attempt to write more than 129 * this amount will result in a truncated log entry. 130 */ 131 #define LOGGER_ENTRY_MAX_PAYLOAD 4068 132 133 /* 134 * The maximum size of a log entry which can be read. 135 * An attempt to read less than this amount may result 136 * in read() returning EINVAL. 137 */ 138 #define LOGGER_ENTRY_MAX_LEN (5 * 1024) 139 140 #ifndef __struct_log_msg_defined 141 #define __struct_log_msg_defined 142 struct log_msg { 143 union { 144 unsigned char buf[LOGGER_ENTRY_MAX_LEN + 1]; 145 struct logger_entry_v4 entry; 146 struct logger_entry_v4 entry_v4; 147 struct logger_entry_v3 entry_v3; 148 struct logger_entry_v2 entry_v2; 149 struct logger_entry entry_v1; 150 } __attribute__((aligned(4))); 151 #ifdef __cplusplus 152 /* Matching log_time operators */ 153 bool operator==(const log_msg& T) const { 154 return (entry.sec == T.entry.sec) && (entry.nsec == T.entry.nsec); 155 } 156 bool operator!=(const log_msg& T) const { 157 return !(*this == T); 158 } 159 bool operator<(const log_msg& T) const { 160 return (entry.sec < T.entry.sec) || 161 ((entry.sec == T.entry.sec) && (entry.nsec < T.entry.nsec)); 162 } 163 bool operator>=(const log_msg& T) const { 164 return !(*this < T); 165 } 166 bool operator>(const log_msg& T) const { 167 return (entry.sec > T.entry.sec) || 168 ((entry.sec == T.entry.sec) && (entry.nsec > T.entry.nsec)); 169 } 170 bool operator<=(const log_msg& T) const { 171 return !(*this > T); 172 } nseclog_msg173 uint64_t nsec() const { 174 return static_cast<uint64_t>(entry.sec) * NS_PER_SEC + entry.nsec; 175 } 176 177 /* packet methods */ idlog_msg178 log_id_t id() { 179 return static_cast<log_id_t>(entry.lid); 180 } msglog_msg181 char* msg() { 182 unsigned short hdr_size = entry.hdr_size; 183 if (!hdr_size) { 184 hdr_size = sizeof(entry_v1); 185 } 186 if ((hdr_size < sizeof(entry_v1)) || (hdr_size > sizeof(entry))) { 187 return NULL; 188 } 189 return reinterpret_cast<char*>(buf) + hdr_size; 190 } lenlog_msg191 unsigned int len() { 192 return (entry.hdr_size ? entry.hdr_size 193 : static_cast<uint16_t>(sizeof(entry_v1))) + 194 entry.len; 195 } 196 #endif 197 }; 198 #endif 199 200 #ifndef __ANDROID_USE_LIBLOG_READER_INTERFACE 201 #ifndef __ANDROID_API__ 202 #define __ANDROID_USE_LIBLOG_READER_INTERFACE 3 203 #elif __ANDROID_API__ > 23 /* > Marshmallow */ 204 #define __ANDROID_USE_LIBLOG_READER_INTERFACE 3 205 #elif __ANDROID_API__ > 22 /* > Lollipop */ 206 #define __ANDROID_USE_LIBLOG_READER_INTERFACE 2 207 #elif __ANDROID_API__ > 19 /* > KitKat */ 208 #define __ANDROID_USE_LIBLOG_READER_INTERFACE 1 209 #else 210 #define __ANDROID_USE_LIBLOG_READER_INTERFACE 0 211 #endif 212 #endif 213 214 #if __ANDROID_USE_LIBLOG_READER_INTERFACE 215 216 struct logger; 217 218 log_id_t android_logger_get_id(struct logger* logger); 219 220 int android_logger_clear(struct logger* logger); 221 long android_logger_get_log_size(struct logger* logger); 222 int android_logger_set_log_size(struct logger* logger, unsigned long size); 223 long android_logger_get_log_readable_size(struct logger* logger); 224 int android_logger_get_log_version(struct logger* logger); 225 226 struct logger_list; 227 228 #if __ANDROID_USE_LIBLOG_READER_INTERFACE > 1 229 ssize_t android_logger_get_statistics(struct logger_list* logger_list, 230 char* buf, size_t len); 231 ssize_t android_logger_get_prune_list(struct logger_list* logger_list, 232 char* buf, size_t len); 233 int android_logger_set_prune_list(struct logger_list* logger_list, char* buf, 234 size_t len); 235 #endif 236 237 #define ANDROID_LOG_RDONLY O_RDONLY 238 #define ANDROID_LOG_WRONLY O_WRONLY 239 #define ANDROID_LOG_RDWR O_RDWR 240 #define ANDROID_LOG_ACCMODE O_ACCMODE 241 #ifndef O_NONBLOCK 242 #define ANDROID_LOG_NONBLOCK 0x00000800 243 #else 244 #define ANDROID_LOG_NONBLOCK O_NONBLOCK 245 #endif 246 #if __ANDROID_USE_LIBLOG_READER_INTERFACE > 2 247 #define ANDROID_LOG_WRAP 0x40000000 /* Block until buffer about to wrap */ 248 #define ANDROID_LOG_WRAP_DEFAULT_TIMEOUT 7200 /* 2 hour default */ 249 #endif 250 #if __ANDROID_USE_LIBLOG_READER_INTERFACE > 1 251 #define ANDROID_LOG_PSTORE 0x80000000 252 #endif 253 254 struct logger_list* android_logger_list_alloc(int mode, unsigned int tail, 255 pid_t pid); 256 struct logger_list* android_logger_list_alloc_time(int mode, log_time start, 257 pid_t pid); 258 void android_logger_list_free(struct logger_list* logger_list); 259 /* In the purest sense, the following two are orthogonal interfaces */ 260 int android_logger_list_read(struct logger_list* logger_list, 261 struct log_msg* log_msg); 262 263 /* Multiple log_id_t opens */ 264 struct logger* android_logger_open(struct logger_list* logger_list, log_id_t id); 265 #define android_logger_close android_logger_free 266 /* Single log_id_t open */ 267 struct logger_list* android_logger_list_open(log_id_t id, int mode, 268 unsigned int tail, pid_t pid); 269 #define android_logger_list_close android_logger_list_free 270 271 #endif /* __ANDROID_USE_LIBLOG_READER_INTERFACE */ 272 273 #ifdef __cplusplus 274 } 275 #endif 276 277 #endif /* _LIBS_LOG_LOG_H */ 278