// Copyright 2011-2022 David Robillard <d@drobilla.net>
// SPDX-License-Identifier: ISC

#ifndef SERD_BUFFER_H
#define SERD_BUFFER_H

#include "serd/attributes.h"
#include "zix/allocator.h"
#include "zix/attributes.h"

#include <stddef.h>

SERD_BEGIN_DECLS

/**
   @defgroup serd_buffer Dynamic Memory Buffers
   @ingroup serd_memory

   The #SerdBuffer type represents a writable area of memory with a known size.

   #SerdWriteFunc and #SerdCloseFunc functions are provided which enable
   writing output to a memory buffer (as `fwrite` and `fclose` do for files).

   @{
*/

/// A dynamically resizable mutable buffer in memory
typedef struct {
  ZixAllocator* ZIX_NULLABLE allocator; ///< Allocator for buf
  void* ZIX_NULLABLE         buf;       ///< Buffer
  size_t                     len;       ///< Size of buffer in bytes
} SerdBuffer;

/**
   A function for writing to a buffer, resizing it if necessary.

   This function can be used as a #SerdWriteFunc to write to a #SerdBuffer
   which is reallocated as necessary.  The `stream` parameter must point to an
   initialized #SerdBuffer.

   Note that when writing a string, the string in the buffer will not be
   null-terminated until serd_buffer_close() is called.
*/
SERD_API size_t
serd_buffer_write(const void* ZIX_NONNULL buf,
                  size_t                  size,
                  size_t                  nmemb,
                  void* ZIX_NONNULL       stream);

/**
   Close the buffer for writing.

   This writes a terminating null byte, so the contents of the buffer are safe
   to read as a string after this call.
*/
SERD_API int
serd_buffer_close(void* ZIX_NONNULL stream);

/**
   @}
*/

SERD_END_DECLS

#endif // SERD_BUFFER_H