1/*
2 * Copyright (C) 2009 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#ifndef _ANDROID_LOG_H
18#define _ANDROID_LOG_H
19
20/******************************************************************
21 *
22 * IMPORTANT NOTICE:
23 *
24 *   This file is part of Android's set of stable system headers
25 *   exposed by the Android NDK (Native Development Kit) since
26 *   platform release 1.5
27 *
28 *   Third-party source AND binary code relies on the definitions
29 *   here to be FROZEN ON ALL UPCOMING PLATFORM RELEASES.
30 *
31 *   - DO NOT MODIFY ENUMS (EXCEPT IF YOU ADD NEW 32-BIT VALUES)
32 *   - DO NOT MODIFY CONSTANTS OR FUNCTIONAL MACROS
33 *   - DO NOT CHANGE THE SIGNATURE OF FUNCTIONS IN ANY WAY
34 *   - DO NOT CHANGE THE LAYOUT OR SIZE OF STRUCTURES
35 */
36
37/*
38 * Support routines to send messages to the Android in-kernel log buffer,
39 * which can later be accessed through the 'logcat' utility.
40 *
41 * Each log message must have
42 *   - a priority
43 *   - a log tag
44 *   - some text
45 *
46 * The tag normally corresponds to the component that emits the log message,
47 * and should be reasonably small.
48 *
49 * Log message text may be truncated to less than an implementation-specific
50 * limit (e.g. 1023 characters max).
51 *
52 * Note that a newline character ("\n") will be appended automatically to your
53 * log message, if not already there. It is not possible to send several messages
54 * and have them appear on a single line in logcat.
55 *
56 * PLEASE USE LOGS WITH MODERATION:
57 *
58 *  - Sending log messages eats CPU and slow down your application and the
59 *    system.
60 *
61 *  - The circular log buffer is pretty small (<64KB), sending many messages
62 *    might push off other important log messages from the rest of the system.
63 *
64 *  - In release builds, only send log messages to account for exceptional
65 *    conditions.
66 *
67 * NOTE: These functions MUST be implemented by /system/lib/liblog.so
68 */
69
70#include <stdarg.h>
71
72#ifdef __cplusplus
73extern "C" {
74#endif
75
76/*
77 * Android log priority values, in ascending priority order.
78 */
79typedef enum android_LogPriority {
80    ANDROID_LOG_UNKNOWN = 0,
81    ANDROID_LOG_DEFAULT,    /* only for SetMinPriority() */
82    ANDROID_LOG_VERBOSE,
83    ANDROID_LOG_DEBUG,
84    ANDROID_LOG_INFO,
85    ANDROID_LOG_WARN,
86    ANDROID_LOG_ERROR,
87    ANDROID_LOG_FATAL,
88    ANDROID_LOG_SILENT,     /* only for SetMinPriority(); must be last */
89} android_LogPriority;
90
91/*
92 * Send a simple string to the log.
93 */
94int __android_log_write(int prio, const char *tag, const char *text);
95
96/*
97 * Send a formatted string to the log, used like printf(fmt,...)
98 */
99int __android_log_print(int prio, const char *tag,  const char *fmt, ...)
100#if defined(__GNUC__)
101    __attribute__ ((format(printf, 3, 4)))
102#endif
103    ;
104
105/*
106 * A variant of __android_log_print() that takes a va_list to list
107 * additional parameters.
108 */
109int __android_log_vprint(int prio, const char *tag,
110                         const char *fmt, va_list ap);
111
112/*
113 * Log an assertion failure and SIGTRAP the process to have a chance
114 * to inspect it, if a debugger is attached. This uses the FATAL priority.
115 */
116void __android_log_assert(const char *cond, const char *tag,
117			  const char *fmt, ...)
118#if defined(__GNUC__)
119    __attribute__ ((noreturn))
120    __attribute__ ((format(printf, 3, 4)))
121#endif
122    ;
123
124#ifdef __cplusplus
125}
126#endif
127
128#endif /* _ANDROID_LOG_H */
129