1 /* 2 ** 3 ** Copyright 2007-2014, The Android Open Source Project 4 ** 5 ** This file is dual licensed. It may be redistributed and/or modified 6 ** under the terms of the Apache 2.0 License OR version 2 of the GNU 7 ** General Public License. 8 */ 9 10 #ifndef _LIBS_LOG_LOGGER_H 11 #define _LIBS_LOG_LOGGER_H 12 13 #include <stdint.h> 14 #include <log/log.h> 15 #include <log/log_read.h> 16 17 #ifdef __cplusplus 18 extern "C" { 19 #endif 20 21 /* 22 * The userspace structure for version 1 of the logger_entry ABI. 23 * This structure is returned to userspace by the kernel logger 24 * driver unless an upgrade to a newer ABI version is requested. 25 */ 26 struct logger_entry { 27 uint16_t len; /* length of the payload */ 28 uint16_t __pad; /* no matter what, we get 2 bytes of padding */ 29 int32_t pid; /* generating process's pid */ 30 int32_t tid; /* generating process's tid */ 31 int32_t sec; /* seconds since Epoch */ 32 int32_t nsec; /* nanoseconds */ 33 char msg[0]; /* the entry's payload */ 34 } __attribute__((__packed__)); 35 36 /* 37 * The userspace structure for version 2 of the logger_entry ABI. 38 * This structure is returned to userspace if ioctl(LOGGER_SET_VERSION) 39 * is called with version==2; or used with the user space log daemon. 40 */ 41 struct logger_entry_v2 { 42 uint16_t len; /* length of the payload */ 43 uint16_t hdr_size; /* sizeof(struct logger_entry_v2) */ 44 int32_t pid; /* generating process's pid */ 45 int32_t tid; /* generating process's tid */ 46 int32_t sec; /* seconds since Epoch */ 47 int32_t nsec; /* nanoseconds */ 48 uint32_t euid; /* effective UID of logger */ 49 char msg[0]; /* the entry's payload */ 50 } __attribute__((__packed__)); 51 52 struct logger_entry_v3 { 53 uint16_t len; /* length of the payload */ 54 uint16_t hdr_size; /* sizeof(struct logger_entry_v3) */ 55 int32_t pid; /* generating process's pid */ 56 int32_t tid; /* generating process's tid */ 57 int32_t sec; /* seconds since Epoch */ 58 int32_t nsec; /* nanoseconds */ 59 uint32_t lid; /* log id of the payload */ 60 char msg[0]; /* the entry's payload */ 61 } __attribute__((__packed__)); 62 63 /* 64 * The maximum size of the log entry payload that can be 65 * written to the logger. An attempt to write more than 66 * this amount will result in a truncated log entry. 67 */ 68 #define LOGGER_ENTRY_MAX_PAYLOAD 4076 69 70 /* 71 * The maximum size of a log entry which can be read from the 72 * kernel logger driver. An attempt to read less than this amount 73 * may result in read() returning EINVAL. 74 */ 75 #define LOGGER_ENTRY_MAX_LEN (5*1024) 76 77 #define NS_PER_SEC 1000000000ULL 78 79 struct log_msg { 80 union { 81 unsigned char buf[LOGGER_ENTRY_MAX_LEN + 1]; 82 struct logger_entry_v3 entry; 83 struct logger_entry_v3 entry_v3; 84 struct logger_entry_v2 entry_v2; 85 struct logger_entry entry_v1; 86 } __attribute__((aligned(4))); 87 #ifdef __cplusplus 88 /* Matching log_time operators */ 89 bool operator== (const log_msg &T) const 90 { 91 return (entry.sec == T.entry.sec) && (entry.nsec == T.entry.nsec); 92 } 93 bool operator!= (const log_msg &T) const 94 { 95 return !(*this == T); 96 } 97 bool operator< (const log_msg &T) const 98 { 99 return (entry.sec < T.entry.sec) 100 || ((entry.sec == T.entry.sec) 101 && (entry.nsec < T.entry.nsec)); 102 } 103 bool operator>= (const log_msg &T) const 104 { 105 return !(*this < T); 106 } 107 bool operator> (const log_msg &T) const 108 { 109 return (entry.sec > T.entry.sec) 110 || ((entry.sec == T.entry.sec) 111 && (entry.nsec > T.entry.nsec)); 112 } 113 bool operator<= (const log_msg &T) const 114 { 115 return !(*this > T); 116 } nseclog_msg117 uint64_t nsec() const 118 { 119 return static_cast<uint64_t>(entry.sec) * NS_PER_SEC + entry.nsec; 120 } 121 122 /* packet methods */ idlog_msg123 log_id_t id() 124 { 125 return (log_id_t) entry.lid; 126 } msglog_msg127 char *msg() 128 { 129 return entry.hdr_size ? (char *) buf + entry.hdr_size : entry_v1.msg; 130 } lenlog_msg131 unsigned int len() 132 { 133 return (entry.hdr_size ? entry.hdr_size : sizeof(entry_v1)) + entry.len; 134 } 135 #endif 136 }; 137 138 struct logger; 139 140 log_id_t android_logger_get_id(struct logger *logger); 141 142 int android_logger_clear(struct logger *logger); 143 long android_logger_get_log_size(struct logger *logger); 144 int android_logger_set_log_size(struct logger *logger, unsigned long size); 145 long android_logger_get_log_readable_size(struct logger *logger); 146 int android_logger_get_log_version(struct logger *logger); 147 148 struct logger_list; 149 150 ssize_t android_logger_get_statistics(struct logger_list *logger_list, 151 char *buf, size_t len); 152 ssize_t android_logger_get_prune_list(struct logger_list *logger_list, 153 char *buf, size_t len); 154 int android_logger_set_prune_list(struct logger_list *logger_list, 155 char *buf, size_t len); 156 157 #define ANDROID_LOG_RDONLY O_RDONLY 158 #define ANDROID_LOG_WRONLY O_WRONLY 159 #define ANDROID_LOG_RDWR O_RDWR 160 #define ANDROID_LOG_ACCMODE O_ACCMODE 161 #define ANDROID_LOG_NONBLOCK O_NONBLOCK 162 #define ANDROID_LOG_PSTORE 0x80000000 163 164 struct logger_list *android_logger_list_alloc(int mode, 165 unsigned int tail, 166 pid_t pid); 167 struct logger_list *android_logger_list_alloc_time(int mode, 168 log_time start, 169 pid_t pid); 170 void android_logger_list_free(struct logger_list *logger_list); 171 /* In the purest sense, the following two are orthogonal interfaces */ 172 int android_logger_list_read(struct logger_list *logger_list, 173 struct log_msg *log_msg); 174 175 /* Multiple log_id_t opens */ 176 struct logger *android_logger_open(struct logger_list *logger_list, 177 log_id_t id); 178 #define android_logger_close android_logger_free 179 /* Single log_id_t open */ 180 struct logger_list *android_logger_list_open(log_id_t id, 181 int mode, 182 unsigned int tail, 183 pid_t pid); 184 #define android_logger_list_close android_logger_list_free 185 186 /* 187 * log_id_t helpers 188 */ 189 log_id_t android_name_to_log_id(const char *logName); 190 const char *android_log_id_to_name(log_id_t log_id); 191 192 #ifdef __cplusplus 193 } 194 #endif 195 196 #endif /* _LIBS_LOG_LOGGER_H */ 197