src/cx/printf.h

/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright 2021 Mike Becker, Olaf Wintermann All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *   1. Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *
 *   2. Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */
/**
 * @file printf.h
 * @brief Wrapper for write-functions with a printf-like interface.
 * @author Mike Becker
 * @author Olaf Wintermann
 * @copyright 2-Clause BSD License
 */

#ifndef UCX_PRINTF_H
#define UCX_PRINTF_H

#include "common.h"
#include "string.h"
#include <stdarg.h>

/**
 * Attribute for printf-like functions.
 * @param fmt_idx index of the format string parameter
 * @param arg_idx index of the first formatting argument
 */
#define cx_attr_printf(fmt_idx, arg_idx) \
    __attribute__((__format__(printf, fmt_idx, arg_idx)))

#ifdef __cplusplus
extern "C" {
#endif


/**
 * The maximum string length that fits into stack memory.
 */
CX_EXPORT extern const unsigned cx_printf_sbo_size;

/**
 * A @c fprintf like function which writes the output to a stream by
 * using a write_func.
 *
 * @param stream the stream the data is written to
 * @param wfc the write function
 * @param fmt format string
 * @param ... additional arguments
 * @return the total number of bytes written or an error code from stdlib printf implementation
 */
cx_attr_nonnull_arg(1, 2, 3) cx_attr_printf(3, 4) cx_attr_cstr_arg(3)
CX_EXPORT int cx_fprintf(void *stream, cx_write_func wfc, const char *fmt, ...);

/**
 * A @c vfprintf like function which writes the output to a stream by
 * using a write_func.
 *
 * @param stream the stream the data is written to
 * @param wfc the write function
 * @param fmt format string
 * @param ap argument list
 * @return the total number of bytes written or an error code from stdlib printf implementation
 * @see cx_fprintf()
 */
cx_attr_nonnull cx_attr_cstr_arg(3)
CX_EXPORT int cx_vfprintf(void *stream, cx_write_func wfc, const char *fmt, va_list ap);

/**
 * An @c asprintf like function which allocates space for a string
 * the result is written to.
 *
 * @note The resulting string is guaranteed to be zero-terminated,
 * unless there was an error, in which case the string's pointer
 * will be @c NULL.
 *
 * @param allocator the CxAllocator used for allocating the string
 * @param fmt format string
 * @param ... additional arguments
 * @return the formatted string
 * @see cx_strfree_a()
 */
cx_attr_nonnull_arg(1, 2) cx_attr_printf(2, 3) cx_attr_cstr_arg(2)
CX_EXPORT cxmutstr cx_asprintf_a(const CxAllocator *allocator, const char *fmt, ...);

/**
 * An @c asprintf like function which allocates space for a string
 * the result is written to.
 *
 * @note The resulting string is guaranteed to be zero-terminated,
 * unless there was an error, in which case the string's pointer
 * will be @c NULL.
 *
 * @param fmt (@c char*) format string
 * @param ... additional arguments
 * @return (@c cxmutstr) the formatted string
 * @see cx_strfree()
 */
#define cx_asprintf(fmt, ...) cx_asprintf_a(cxDefaultAllocator, fmt, __VA_ARGS__)

/**
* A @c vasprintf like function which allocates space for a string
 * the result is written to.
 *
 * @note The resulting string is guaranteed to be zero-terminated,
 * unless there was an error, in which case the string's pointer
 * will be @c NULL.
 *
 * @param allocator the CxAllocator used for allocating the string
 * @param fmt format string
 * @param ap argument list
 * @return the formatted string
 * @see cx_asprintf_a()
 */
cx_attr_nonnull cx_attr_cstr_arg(2)
CX_EXPORT cxmutstr cx_vasprintf_a(const CxAllocator *allocator, const char *fmt, va_list ap);

/**
* A @c vasprintf like function which allocates space for a string
 * the result is written to.
 *
 * @note The resulting string is guaranteed to be zero-terminated,
 * unless there was an error, in which case the string's pointer
 * will be @c NULL.
 *
 * @param fmt (@c char*) format string
 * @param ap (@c va_list) argument list
 * @return (@c cxmutstr) the formatted string
 * @see cx_asprintf()
 */
#define cx_vasprintf(fmt, ap) cx_vasprintf_a(cxDefaultAllocator, fmt, ap)

/**
 * A @c printf like function which writes the output to a CxBuffer.
 *
 * @param buffer (@c CxBuffer*) a pointer to the buffer the data is written to
 * @param fmt (@c char*) the format string
 * @param ... additional arguments
 * @return (@c int) the total number of bytes written or an error code from stdlib printf implementation
 * @see cx_fprintf()
 * @see cxBufferWrite()
 */
#define cx_bprintf(buffer, fmt, ...) cx_fprintf((void*)buffer, cxBufferWriteFunc, fmt, __VA_ARGS__)


/**
 * An @c sprintf like function which reallocates the string when the buffer is not large enough.
 *
 * The size of the buffer will be updated in @p len when necessary.
 *
 * @note The resulting string, if successful, is guaranteed to be zero-terminated.
 *
 * @param str (@c char**) a pointer to the string buffer
 * @param len (@c size_t*) a pointer to the length of the buffer
 * @param fmt (@c char*) the format string
 * @param ... additional arguments
 * @return (@c int) the length of the produced string or an error code from stdlib printf implementation
 */
#define cx_sprintf(str, len, fmt, ...) cx_sprintf_a(cxDefaultAllocator, str, len, fmt, __VA_ARGS__)

/**
 * An @c sprintf like function which reallocates the string when the buffer is not large enough.
 *
 * The size of the buffer will be updated in @p len when necessary.
 *
 * @note The resulting string, if successful, is guaranteed to be zero-terminated.
 *
 * @attention The original buffer MUST have been allocated with the same allocator!
 *
 * @param alloc the allocator to use
 * @param str a pointer to the string buffer
 * @param len a pointer to the length of the buffer
 * @param fmt the format string
 * @param ... additional arguments
 * @return the length of the produced string or an error code from stdlib printf implementation
 */
cx_attr_nonnull_arg(1, 2, 3, 4) cx_attr_printf(4, 5) cx_attr_cstr_arg(4)
CX_EXPORT int cx_sprintf_a(const CxAllocator *alloc, char **str, size_t *len, const char *fmt, ...);


/**
 * An @c sprintf like function which reallocates the string when the buffer is not large enough.
 *
 * The size of the buffer will be updated in @p len when necessary.
 *
 * @note The resulting string, if successful, is guaranteed to be zero-terminated.
 *
 * @param str (@c char**) a pointer to the string buffer
 * @param len (@c size_t*) a pointer to the length of the buffer
 * @param fmt (@c char*) the format string
 * @param ap (@c va_list) argument list
 * @return (@c int) the length of the produced string or an error code from stdlib printf implementation
 */
#define cx_vsprintf(str, len, fmt, ap) cx_vsprintf_a(cxDefaultAllocator, str, len, fmt, ap)

/**
 * An @c sprintf like function which reallocates the string when the buffer is not large enough.
 *
 * The size of the buffer will be updated in @p len when necessary.
 *
 * @note The resulting string is guaranteed to be zero-terminated.
 *
 * @attention The original buffer MUST have been allocated with the same allocator!
 *
 * @param alloc the allocator to use
 * @param str a pointer to the string buffer
 * @param len a pointer to the length of the buffer
 * @param fmt the format string
 * @param ap argument list
 * @return the length of the produced string or an error code from stdlib printf implementation
 */
cx_attr_nonnull  cx_attr_cstr_arg(4) cx_attr_access_rw(2) cx_attr_access_rw(3)
CX_EXPORT int cx_vsprintf_a(const CxAllocator *alloc, char **str, size_t *len, const char *fmt, va_list ap);


/**
 * An @c sprintf like function which allocates a new string when the buffer is not large enough.
 *
 * The size of the buffer will be updated in @p len when necessary.
 *
 * The location of the resulting string will @em always be stored to @p str. When the buffer
 * was sufficiently large, @p buf itself will be stored to the location of @p str.
 *
 * @note The resulting string, if successful, is guaranteed to be zero-terminated.
 * 
 * @remark When a new string needed to be allocated, the contents of @p buf will be
 * poisoned after the call, because this function tries to produce the string in @p buf, first.
 *
 * @param buf (@c char*) a pointer to the buffer
 * @param len (@c size_t*) a pointer to the length of the buffer
 * @param str (@c char**) a pointer where the location of the result shall be stored
 * @param fmt (@c char*) the format string
 * @param ... additional arguments
 * @return (@c int) the length of the produced string or an error code from stdlib printf implementation
 */
#define cx_sprintf_s(buf, len, str, fmt, ...) cx_sprintf_sa(cxDefaultAllocator, buf, len, str, fmt, __VA_ARGS__)

/**
 * An @c sprintf like function which allocates a new string when the buffer is not large enough.
 *
 * The size of the buffer will be updated in @p len when necessary.
 *
 * The location of the resulting string will @em always be stored to @p str. When the buffer
 * was sufficiently large, @p buf itself will be stored to the location of @p str.
 *
 * @note The resulting string, if successful, is guaranteed to be zero-terminated.
 *
 * @remark When a new string needed to be allocated, the contents of @p buf will be
 * poisoned after the call, because this function tries to produce the string in @p buf, first.
 *
 * @param alloc the allocator to use
 * @param buf a pointer to the buffer
 * @param len a pointer to the length of the buffer
 * @param str a pointer where the location of the result shall be stored
 * @param fmt the format string
 * @param ... additional arguments
 * @return the length of the produced string or an error code from stdlib printf implementation
 */
cx_attr_nonnull_arg(1, 2, 4, 5) cx_attr_printf(5, 6) cx_attr_cstr_arg(5)
cx_attr_access_rw(2) cx_attr_access_rw(3) cx_attr_access_rw(4)
CX_EXPORT int cx_sprintf_sa(const CxAllocator *alloc, char *buf, size_t *len, char **str, const char *fmt, ...);

/**
 * An @c sprintf like function which allocates a new string when the buffer is not large enough.
 *
 * The size of the buffer will be updated in @p len when necessary.
 *
 * The location of the resulting string will @em always be stored to @p str. When the buffer
 * was sufficiently large, @p buf itself will be stored to the location of @p str.
 *
 * @note The resulting string is guaranteed to be zero-terminated.
 *
 * @remark When a new string needed to be allocated, the contents of @p buf will be
 * poisoned after the call, because this function tries to produce the string in @p buf, first.
 *
 * @param buf (@c char*) a pointer to the buffer
 * @param len (@c size_t*) a pointer to the length of the buffer
 * @param str (@c char**) a pointer where the location of the result shall be stored
 * @param fmt (@c char*) the format string
 * @param ap (@c va_list) argument list
 * @return (@c int) the length of the produced string or an error code from stdlib printf implementation
 */
#define cx_vsprintf_s(buf, len, str, fmt, ap) cx_vsprintf_sa(cxDefaultAllocator, buf, len, str, fmt, ap)

/**
 * An @c sprintf like function which allocates a new string when the buffer is not large enough.
 *
 * The size of the buffer will be updated in @p len when necessary.
 *
 * The location of the resulting string will @em always be stored to @p str. When the buffer
 * was sufficiently large, @p buf itself will be stored to the location of @p str.
 *
 * @note The resulting string is guaranteed to be zero-terminated.
 *
 * @remark When a new string needed to be allocated, the contents of @p buf will be
 * poisoned after the call, because this function tries to produce the string in @p buf, first.
 *
 * @param alloc the allocator to use
 * @param buf a pointer to the buffer
 * @param len a pointer to the length of the buffer
 * @param str a pointer where the location of the result shall be stored
 * @param fmt the format string
 * @param ap argument list
 * @return the length of the produced string or an error code from stdlib printf implementation
 */
cx_attr_nonnull cx_attr_cstr_arg(5)
CX_EXPORT int cx_vsprintf_sa(const CxAllocator *alloc, char *buf, size_t *len, char **str, const char *fmt, va_list ap);


#ifdef __cplusplus
} // extern "C"
#endif

#endif //UCX_PRINTF_H