1 /* 2 * Copyright (C) 2008 The Android Open Source Project 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in 12 * the documentation and/or other materials provided with the 13 * distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 #include <time.h> 29 #include <stdio.h> 30 #include <pthread.h> 31 #include <unistd.h> 32 #include <sys/types.h> 33 #include <sys/uio.h> 34 #include <arpa/inet.h> 35 #include <errno.h> 36 #include <string.h> 37 #include <stdlib.h> 38 #include <stdarg.h> 39 #include <fcntl.h> 40 41 #include "logd.h" 42 43 /* should match system/core/include/cutils/logger.h */ 44 #define LOGGER_LOG_MAIN "log/main" 45 #define LOGGER_LOG_RADIO "log/radio" 46 #define LOGGER_LOG_EVENTS "log/events" 47 #define LOGGER_LOG_SYSTEM "log/system" 48 49 #include <pthread.h> 50 51 /* IMPORTANT IMPORTANT IMPORTANT: TECHNICAL NOTE 52 * 53 * Some of the functions below can be called when our malloc() implementation 54 * has detected that the heap is corrupted, or even from a signal handler. 55 * 56 * These functions should *not* use a function that allocates heap memory 57 * or is not signal-safe. Using direct system calls is acceptable, and we 58 * also assume that pthread_mutex_lock/unlock can be used too. 59 */ 60 61 #define LOG_BUF_SIZE 1024 62 63 typedef enum { 64 LOG_ID_NONE = 0, 65 LOG_ID_MAIN, 66 LOG_ID_RADIO, 67 LOG_ID_MAX 68 } log_id_t; 69 70 /* logger handles writing to object, pointed by log channel id */ 71 typedef int (*logger_function_t)(log_id_t log_id, struct iovec *vec); 72 73 typedef struct { 74 logger_function_t logger; 75 int fd; 76 const char *path; 77 } log_channel_t; 78 79 static int __write_to_log_init(log_id_t log_id, struct iovec *vec); 80 static int __write_to_log_null(log_id_t log_id, struct iovec *vec); 81 82 static pthread_mutex_t log_init_lock = PTHREAD_MUTEX_INITIALIZER; 83 84 static log_channel_t log_channels[LOG_ID_MAX] = { 85 { __write_to_log_null, -1, NULL }, 86 { __write_to_log_init, -1, "/dev/"LOGGER_LOG_MAIN }, 87 { __write_to_log_init, -1, "/dev/"LOGGER_LOG_RADIO } 88 }; 89 90 /* Important: see technical note at start of source file */ 91 static int __write_to_log_null(log_id_t log_id, struct iovec *vec) 92 { 93 /* 94 * ALTERED behaviour from previous version 95 * always returns successful result 96 */ 97 int i = 0; 98 size_t res = 0; 99 100 for ( ; i < 3; ++i) { 101 res += vec[i].iov_len; 102 } 103 104 return (int)res; 105 } 106 107 /* 108 * it's supposed, that log_id contains valid id always. 109 * this check must be performed in higher level functions 110 */ 111 /* Important: see technical note at start of source file */ 112 static int __write_to_log_kernel(log_id_t log_id, struct iovec *vec) 113 { 114 return TEMP_FAILURE_RETRY( writev(log_channels[log_id].fd, vec, 3) ); 115 } 116 117 /* Important: see technical note at start of source file */ 118 static int __write_to_log_init(log_id_t log_id, struct iovec *vec) 119 { 120 if ((LOG_ID_NONE < log_id) && (log_id < LOG_ID_MAX)) { 121 int fd; 122 123 pthread_mutex_lock(&log_init_lock); 124 125 fd = TEMP_FAILURE_RETRY(open(log_channels[log_id].path, O_WRONLY)); 126 127 log_channels[log_id].logger = 128 (fd < 0) ? __write_to_log_null : __write_to_log_kernel; 129 log_channels[log_id].fd = fd; 130 131 log_channels[log_id].fd = fd; 132 133 pthread_mutex_unlock(&log_init_lock); 134 135 return log_channels[log_id].logger(log_id, vec); 136 } 137 138 /* log_id is invalid */ 139 return -1; 140 } 141 142 /* Important: see technical note at start of source file */ 143 __LIBC_HIDDEN__ 144 int __libc_android_log_write(int prio, const char *tag, const char *msg) 145 { 146 struct iovec vec[3]; 147 log_id_t log_id = LOG_ID_MAIN; 148 149 if (tag == NULL) 150 tag = ""; 151 152 if (!strcmp(tag, "HTC_RIL")) 153 log_id = LOG_ID_RADIO; 154 155 vec[0].iov_base = (unsigned char *) &prio; 156 vec[0].iov_len = 1; 157 vec[1].iov_base = (void *) tag; 158 vec[1].iov_len = strlen(tag) + 1; 159 vec[2].iov_base = (void *) msg; 160 vec[2].iov_len = strlen(msg) + 1; 161 162 return log_channels[log_id].logger(log_id, vec); 163 } 164 165 /* The functions below are not designed to be called from a heap panic 166 * function or from a signal handler. As such, they are free to use complex 167 * C library functions like vsnprintf() 168 */ 169 __LIBC_HIDDEN__ 170 int __libc_android_log_vprint(int prio, const char *tag, const char *fmt, 171 va_list ap) 172 { 173 char buf[LOG_BUF_SIZE]; 174 175 vsnprintf(buf, LOG_BUF_SIZE, fmt, ap); 176 177 return __libc_android_log_write(prio, tag, buf); 178 } 179 180 __LIBC_HIDDEN__ 181 int __libc_android_log_print(int prio, const char *tag, const char *fmt, ...) 182 { 183 va_list ap; 184 char buf[LOG_BUF_SIZE]; 185 186 va_start(ap, fmt); 187 vsnprintf(buf, LOG_BUF_SIZE, fmt, ap); 188 va_end(ap); 189 190 return __libc_android_log_write(prio, tag, buf); 191 } 192 193 __LIBC_HIDDEN__ 194 int __libc_android_log_assert(const char *cond, const char *tag, 195 const char *fmt, ...) 196 { 197 va_list ap; 198 char buf[LOG_BUF_SIZE]; 199 200 va_start(ap, fmt); 201 vsnprintf(buf, LOG_BUF_SIZE, fmt, ap); 202 va_end(ap); 203 204 __libc_android_log_write(ANDROID_LOG_FATAL, tag, buf); 205 206 exit(1); 207 208 return -1; 209 } 210
