xref: /device/soc/rockchip/rk2206/sdk_liteos/platform/system/printf.h

/*
 * Copyright (c) 2022 FuZhou Lockzhiner Electronic Co., Ltd. All rights reserved.
 * 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.
 */
#ifndef _PRINTF_H_
#define _PRINTF_H_

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

#ifdef __cplusplus
extern "C" {
#endif


/**
 * 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 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  vsnprintf_
#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);


/**
 * 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  // _PRINTF_H_