blob: b2f0ed9743f90766d344b9ce0cac5d73e77e48ef [file] [log] [blame]
/*
* Copyright (C) 2009 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#pragma once
/**
* @addtogroup Logging
* @{
*/
/**
* \file
*
* Support routines to send messages to the Android log buffer,
* which can later be accessed through the `logcat` utility.
*
* Each log message must have
* - a priority
* - a log tag
* - some text
*
* The tag normally corresponds to the component that emits the log message,
* and should be reasonably small.
*
* Log message text may be truncated to less than an implementation-specific
* limit (1023 bytes).
*
* Note that a newline character ("\n") will be appended automatically to your
* log message, if not already there. It is not possible to send several
* messages and have them appear on a single line in logcat.
*
* Please use logging in moderation:
*
* - Sending log messages eats CPU and slow down your application and the
* system.
*
* - The circular log buffer is pretty small, so sending many messages
* will hide other important log messages.
*
* - In release builds, only send log messages to account for exceptional
* conditions.
*/
#include <stdarg.h>
#ifdef __cplusplus
extern "C" {
#endif
/**
* Android log priority values, in increasing order of priority.
*/
typedef enum android_LogPriority {
/** For internal use only. */
ANDROID_LOG_UNKNOWN = 0,
/** The default priority, for internal use only. */
ANDROID_LOG_DEFAULT, /* only for SetMinPriority() */
/** Verbose logging. Should typically be disabled for a release apk. */
ANDROID_LOG_VERBOSE,
/** Debug logging. Should typically be disabled for a release apk. */
ANDROID_LOG_DEBUG,
/** Informational logging. Should typically be disabled for a release apk. */
ANDROID_LOG_INFO,
/** Warning logging. For use with recoverable failures. */
ANDROID_LOG_WARN,
/** Error logging. For use with unrecoverable failures. */
ANDROID_LOG_ERROR,
/** Fatal logging. For use when aborting. */
ANDROID_LOG_FATAL,
/** For internal use only. */
ANDROID_LOG_SILENT, /* only for SetMinPriority(); must be last */
} android_LogPriority;
/**
* Writes the constant string `text` to the log, with priority `prio` and tag
* `tag`.
*/
int __android_log_write(int prio, const char* tag, const char* text);
/**
* Writes a formatted string to the log, with priority `prio` and tag `tag`.
* The details of formatting are the same as for
* [printf(3)](http://man7.org/linux/man-pages/man3/printf.3.html).
*/
int __android_log_print(int prio, const char* tag, const char* fmt, ...)
#if defined(__GNUC__)
__attribute__((__format__(printf, 3, 4)))
#endif
;
/**
* Equivalent to `__android_log_print`, but taking a `va_list`.
* (If `__android_log_print` is like `printf`, this is like `vprintf`.)
*/
int __android_log_vprint(int prio, const char* tag, const char* fmt, va_list ap)
#if defined(__GNUC__)
__attribute__((__format__(printf, 3, 0)))
#endif
;
/**
* Writes an assertion failure to the log (as `ANDROID_LOG_FATAL`) and to
* stderr, before calling
* [abort(3)](http://man7.org/linux/man-pages/man3/abort.3.html).
*
* If `fmt` is non-null, `cond` is unused. If `fmt` is null, the string
* `Assertion failed: %s` is used with `cond` as the string argument.
* If both `fmt` and `cond` are null, a default string is provided.
*
* Most callers should use
* [assert(3)](http://man7.org/linux/man-pages/man3/assert.3.html) from
* `<assert.h>` instead, or the `__assert` and `__assert2` functions provided by
* bionic if more control is needed. They support automatically including the
* source filename and line number more conveniently than this function.
*/
void __android_log_assert(const char* cond, const char* tag, const char* fmt,
...)
#if defined(__GNUC__)
__attribute__((__noreturn__))
__attribute__((__format__(printf, 3, 4)))
#endif
;
#ifndef log_id_t_defined
#define log_id_t_defined
/**
* Identifies a specific log buffer for __android_log_buf_write()
* and __android_log_buf_print().
*/
typedef enum log_id {
LOG_ID_MIN = 0,
/** The main log buffer. This is the only log buffer available to apps. */
LOG_ID_MAIN = 0,
/** The radio log buffer. */
LOG_ID_RADIO = 1,
/** The event log buffer. */
LOG_ID_EVENTS = 2,
/** The system log buffer. */
LOG_ID_SYSTEM = 3,
/** The crash log buffer. */
LOG_ID_CRASH = 4,
/** The statistics log buffer. */
LOG_ID_STATS = 5,
/** The security log buffer. */
LOG_ID_SECURITY = 6,
/** The kernel log buffer. */
LOG_ID_KERNEL = 7,
LOG_ID_MAX
} log_id_t;
#endif
/**
* Writes the constant string `text` to the log buffer `id`,
* with priority `prio` and tag `tag`.
*
* Apps should use __android_log_write() instead.
*/
int __android_log_buf_write(int bufID, int prio, const char* tag,
const char* text);
/**
* Writes a formatted string to log buffer `id`,
* with priority `prio` and tag `tag`.
* The details of formatting are the same as for
* [printf(3)](http://man7.org/linux/man-pages/man3/printf.3.html).
*
* Apps should use __android_log_print() instead.
*/
int __android_log_buf_print(int bufID, int prio, const char* tag,
const char* fmt, ...)
#if defined(__GNUC__)
__attribute__((__format__(printf, 4, 5)))
#endif
;
#ifdef __cplusplus
}
#endif
/** @} */