Telodendria/src/include/Log.h

/*
 * Copyright (C) 2022-2023 Jordan Bancino <@jordan:bancino.net>
 *
 * Permission is hereby granted, free of charge, to any person
 * obtaining a copy of this software and associated documentation files
 * (the "Software"), to deal in the Software without restriction,
 * including without limitation the rights to use, copy, modify, merge,
 * publish, distribute, sublicense, and/or sell copies of the Software,
 * and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#ifndef TELODENDRIA_LOG_H
#define TELODENDRIA_LOG_H

/***
 * @Nm Log
 * @Nd A simple logging framework for logging to multiple destinations.
 * @Dd April 27 2023
 * @Xr Stream
 *
 * .Nm
 * is a simple C logging library that allows for colorful outputs,
 * timestamps, and custom log levels. It also features the ability to
 * have multiple logs open at one time, although Telodendria primarily
 * utilizes the global log. All logs are thread safe.
 */

#include <stdio.h>
#include <stddef.h>
#include <syslog.h>

#include <Stream.h>

#define LOG_FLAG_COLOR  (1 << 0)
#define LOG_FLAG_SYSLOG (1 << 1)

/**
 * A log is defined as a configuration that describes the properties
 * of the log. This opaque structure can be manipulated by the
 * functions defined in this API.
 */
typedef struct LogConfig LogConfig;

/**
 * Create a new log configuration with sane defaults that can be used
 * immediately with the logging functions.
 */
extern LogConfig * LogConfigCreate(void);

/**
 * Get the global log configuration, creating a new one with
 * .Fn LogConfigCreate
 * if necessary.
 */
extern LogConfig * LogConfigGlobal(void);

/**
 * Free the given log configuration. Note that this does not close the
 * underlying stream associated with the log, if there is one. Also
 * note that to avoid memory leaks, the global log configuration must
 * also be freed, but it cannot be used after it is freed.
 */
extern void LogConfigFree(LogConfig *);

/**
 * Set the current log level on the specified log configuration.
 * This indicates that only messages at or above this level should be
 * logged; all others are silently discarded. The passed log level
 * should be one of the log levels defined by
 * .Xr syslog 3 .
 * Refer to that page for a complete list of acceptable log levels,
 * and note that passing an invalid log level will result in undefined
 * behavior.
 */
extern void LogConfigLevelSet(LogConfig *, int);

/**
 * Cause the log output to be indented two more spaces than it was
 * previously. This can be helpful when generating stack traces or
 * other hierarchical output. This is a simple convenience wrapper
 * around
 * .Fn LogConfigIndentSet .
 */
extern void LogConfigIndent(LogConfig *);

/**
 * Cause the log output to be indented two less spaces than it was
 * previously. This is a simple convenience wrapper around
 * .Fn LogConfigIndentSet .
 */
extern void LogConfigUnindent(LogConfig *);

/**
 * Indent future log output using the specified config by some
 * arbitrary amount.
 */
extern void LogConfigIndentSet(LogConfig *, size_t);

extern void
 LogConfigOutputSet(LogConfig *, Stream *);

extern void
 LogConfigFlagSet(LogConfig *, int);

extern void
 LogConfigFlagClear(LogConfig *, int);

extern void
 LogConfigTimeStampFormatSet(LogConfig *, char *);

extern void
 Logv(LogConfig *, int, const char *, va_list);

extern void
 LogTo(LogConfig *, int, const char *,...);

extern void
 Log(int, const char *,...);

#endif