1 /* 2 * Copyright (C) 2008 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 #include <sys/stat.h> 18 #include <sys/types.h> 19 #include <fcntl.h> 20 #include <stdarg.h> 21 #include <stdio.h> 22 #include <stdlib.h> 23 #include <string.h> 24 #include <unistd.h> 25 26 #include <cutils/klog.h> 27 28 static int klog_fd = -1; 29 static int klog_level = KLOG_DEFAULT_LEVEL; 30 31 void klog_set_level(int level) { 32 klog_level = level; 33 } 34 35 void klog_init(void) 36 { 37 static const char *name = "/dev/__kmsg__"; 38 39 if (klog_fd >= 0) return; /* Already initialized */ 40 41 if (mknod(name, S_IFCHR | 0600, (1 << 8) | 11) == 0) { 42 klog_fd = open(name, O_WRONLY); 43 if (klog_fd < 0) 44 return; 45 fcntl(klog_fd, F_SETFD, FD_CLOEXEC); 46 unlink(name); 47 } 48 } 49 50 #define LOG_BUF_MAX 512 51 52 void klog_write(int level, const char *fmt, ...) 53 { 54 char buf[LOG_BUF_MAX]; 55 va_list ap; 56 57 if (level > klog_level) return; 58 if (klog_fd < 0) klog_init(); 59 if (klog_fd < 0) return; 60 61 va_start(ap, fmt); 62 vsnprintf(buf, LOG_BUF_MAX, fmt, ap); 63 buf[LOG_BUF_MAX - 1] = 0; 64 va_end(ap); 65 write(klog_fd, buf, strlen(buf)); 66 } 67
