u-tools/apps/adb/log_service.c

   1 /*
   2  * Copyright (C) 2007 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 #include <stdlib.h>
  19 #include <stdio.h>
  20 #include <unistd.h>
  21 #include <string.h>
  22 #include <fcntl.h>
  23 #include <errno.h>
  24 #include <sys/socket.h>
  25 #include <cutils/logger.h>
  26 #include "sysdeps.h"
  27 #include "adb.h"
  28
  29 #define LOG_FILE_DIR    "/dev/log/"
  30
  31 void write_log_entry(int fd, struct logger_entry *buf);
  32
  33 void log_service(int fd, void *cookie)
  34 {
  35     /* get the name of the log filepath to read */
  36     char * log_filepath = cookie;
  37
  38     /* open the log file. */
  39     int logfd = unix_open(log_filepath, O_RDONLY);
  40     if (logfd < 0) {
  41         goto done;
  42     }
  43
  44     // temp buffer to read the entries
  45     unsigned char buf[LOGGER_ENTRY_MAX_LEN + 1] __attribute__((aligned(4)));
  46     struct logger_entry *entry = (struct logger_entry *) buf;
  47
  48     while (1) {
  49         int ret;
  50
  51         ret = unix_read(logfd, entry, LOGGER_ENTRY_MAX_LEN);
  52         if (ret < 0) {
  53             if (errno == EINTR || errno == EAGAIN)
  54                 continue;
  55             // perror("logcat read");
  56             goto done;
  57         }
  58         else if (!ret) {
  59             // fprintf(stderr, "read: Unexpected EOF!\n");
  60             goto done;
  61         }
  62
  63         /* NOTE: driver guarantees we read exactly one full entry */
  64
  65         entry->msg[entry->len] = '\0';
  66
  67         write_log_entry(fd, entry);
  68     }
  69
  70 done:
  71     unix_close(fd);
  72     free(log_filepath);
  73 }
  74
  75 /* returns the full path to the log file in a newly allocated string */
  76 char * get_log_file_path(const char * log_name) {
  77     char *log_device = malloc(strlen(LOG_FILE_DIR) + strlen(log_name) + 1);
  78
  79     strcpy(log_device, LOG_FILE_DIR);
  80     strcat(log_device, log_name);
  81
  82     return log_device;
  83 }
  84
  85
  86 /* prints one log entry into the file descriptor fd */
  87 void write_log_entry(int fd, struct logger_entry *buf)
  88 {
  89     size_t size = sizeof(struct logger_entry) + buf->len;
  90
  91     writex(fd, buf, size);
  92 }