lib/libc/include/stdio.h

/*
 * SPDX-License-Identifier: MIT
 * SPDX-FileCopyrightText: Copyright Marco Paland (info@paland.com), PALANDesign Hannover, Germany
 * SPDX-FileCopyrightText: Copyright TF-RMM Contributors.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * n 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 substantial 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.
 *
 * \brief Tiny printf, sprintf and snprintf implementation, optimized for
 * speed on
 *        embedded systems with a very limited resources.
 *        Use this instead of bloated standard/newlib printf.
 *        These routines are thread safe and reentrant.
 */

#ifndef STDIO_H
#define STDIO_H

#include <stdarg.h>
#include <stddef.h>


#ifdef __cplusplus
extern "C" {
#endif


/**
 * Output a character to a custom device like UART, used by the printf() function
 * This function is declared here only. You have to write your custom implementation somewhere
 * \param character: Character to output
 */
void _putchar(char character);


/**
 * Tiny printf implementation
 * You have to implement _putchar if you use printf()
 * To avoid conflicts with the regular printf() API it is overridden by macro defines
 * and internal underscore-appended functions like printf_() are used
 * \param format A string that specifies the format of the output
 * \return The number of characters that are written into the array, not counting the terminating null character
 */
#define printf printf_
int printf_(const char *format, ...);


/**
 * Tiny sprintf implementation
 * Due to security reasons (buffer overflow) YOU SHOULD CONSIDER USING (V)SNPRINTF INSTEAD!
 * \param buffer A pointer to the buffer where to store the formatted string. MUST be big enough to store the output!
 * \param format A string that specifies the format of the output
 * \return The number of characters that are WRITTEN into the buffer, not counting the terminating null character
 */
#define sprintf sprintf_
int sprintf_(char *buffer, const char *format, ...);


/**
 * Tiny snprintf/vsnprintf implementation
 * \param buffer A pointer to the buffer where to store the formatted string
 * \param count The maximum number of characters to store in the buffer, including a terminating null character
 * \param format A string that specifies the format of the output
 * \param va A value identifying a variable arguments list
 * \return The number of characters that COULD have been written into the buffer, not counting the terminating
 *         null character. A value equal or larger than count indicates truncation. Only when the returned value
 *         is non-negative and less than count, the string has been completely written.
 */
#define snprintf  snprintf_
#define vsnprintf vsnprintf_
int  snprintf_(char *buffer, size_t count, const char *format, ...);
int vsnprintf_(char *buffer, size_t count, const char *format, va_list va);


/**
 * Tiny vprintf implementation
 * \param format A string that specifies the format of the output
 * \param va A value identifying a variable arguments list
 * \return The number of characters that are WRITTEN into the buffer, not counting the terminating null character
 */
#define vprintf vprintf_
int vprintf_(const char *format, va_list va);


/**
 * printf with output function
 * You may use this as dynamic alternative to printf() with its fixed _putchar() output
 * \param out An output function which takes one character and an argument pointer
 * \param arg An argument pointer for user data passed to output function
 * \param format A string that specifies the format of the output
 * \return The number of characters that are sent to the output function, not counting the terminating null character
 */
int fctprintf(void (*out)(char character, void *arg), void *arg,
	      const char *format, ...);


#ifdef __cplusplus
}
#endif


#endif  /* STDIO_H */