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
klog_get_level(void)31 int klog_get_level(void) {
32 return klog_level;
33 }
34
klog_set_level(int level)35 void klog_set_level(int level) {
36 klog_level = level;
37 }
38
klog_init(void)39 void klog_init(void)
40 {
41 static const char *name = "/dev/__kmsg__";
42
43 if (klog_fd >= 0) return; /* Already initialized */
44
45 if (mknod(name, S_IFCHR | 0600, (1 << 8) | 11) == 0) {
46 klog_fd = open(name, O_WRONLY);
47 if (klog_fd < 0)
48 return;
49 fcntl(klog_fd, F_SETFD, FD_CLOEXEC);
50 unlink(name);
51 }
52 }
53
54 #define LOG_BUF_MAX 512
55
klog_vwrite(int level,const char * fmt,va_list ap)56 void klog_vwrite(int level, const char *fmt, va_list ap)
57 {
58 char buf[LOG_BUF_MAX];
59
60 if (level > klog_level) return;
61 if (klog_fd < 0) klog_init();
62 if (klog_fd < 0) return;
63
64 vsnprintf(buf, LOG_BUF_MAX, fmt, ap);
65 buf[LOG_BUF_MAX - 1] = 0;
66
67 write(klog_fd, buf, strlen(buf));
68 }
69
klog_write(int level,const char * fmt,...)70 void klog_write(int level, const char *fmt, ...)
71 {
72 va_list ap;
73 va_start(ap, fmt);
74 klog_vwrite(level, fmt, ap);
75 va_end(ap);
76 }
77