/*
 * Copyright (c) 2008-2013, Dave Benson.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *
 *     * 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
 * OWNER 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.
 */

#ifndef __PROTOBUF_C_DATA_BUFFER_H_
#define __PROTOBUF_C_DATA_BUFFER_H_

#include "protobuf-c.h"
#include <stdarg.h>


typedef struct _ProtobufCDataBuffer ProtobufCDataBuffer;
typedef struct _ProtobufCDataBufferFragment ProtobufCDataBufferFragment;

struct _ProtobufCDataBufferFragment
{
  ProtobufCDataBufferFragment *next;
  unsigned buf_start;	/* offset in buf of valid data */
  unsigned buf_length;	/* length of valid data in buf */
};

struct _ProtobufCDataBuffer
{
  size_t size;

  ProtobufCDataBufferFragment    *first_frag;
  ProtobufCDataBufferFragment    *last_frag;
  ProtobufCAllocator *allocator;
};

void     protobuf_c_data_buffer_init                (ProtobufCDataBuffer       *buffer,
                                                     ProtobufCAllocator    *allocator);
void     protobuf_c_data_buffer_clear               (ProtobufCDataBuffer       *buffer);
void     protobuf_c_data_buffer_reset               (ProtobufCDataBuffer       *buffer);

size_t   protobuf_c_data_buffer_read                (ProtobufCDataBuffer    *buffer,
                                                     void*      data,
                                                     size_t         max_length);
size_t   protobuf_c_data_buffer_peek                (const ProtobufCDataBuffer* buffer,
                                                     void*      data,
                                                     size_t        max_length);
size_t   protobuf_c_data_buffer_discard             (ProtobufCDataBuffer    *buffer,
                                                     size_t        max_discard);
char    *protobuf_c_data_buffer_read_line           (ProtobufCDataBuffer    *buffer);

char    *protobuf_c_data_buffer_parse_string0       (ProtobufCDataBuffer    *buffer);
                        /* Returns first char of buffer, or -1. */
int      protobuf_c_data_buffer_peek_char           (const ProtobufCDataBuffer *buffer);
int      protobuf_c_data_buffer_read_char           (ProtobufCDataBuffer    *buffer);

int      protobuf_c_data_buffer_index_of(ProtobufCDataBuffer *buffer,
                                         char       char_to_find);
/* 
 * Appending to the buffer.
 */
void     protobuf_c_data_buffer_append              (ProtobufCDataBuffer    *buffer, 
                                         const void   *data,
                                         size_t        length);
void     protobuf_c_data_buffer_append_string       (ProtobufCDataBuffer    *buffer, 
                                         const char   *string);
void     protobuf_c_data_buffer_append_char         (ProtobufCDataBuffer    *buffer, 
                                         char          character);
void     protobuf_c_data_buffer_append_repeated_char(ProtobufCDataBuffer    *buffer, 
                                         char          character,
                                         size_t        count);
#define protobuf_c_data_buffer_append_zeros(buffer, count) \
  protobuf_c_data_buffer_append_repeated_char ((buffer), 0, (count))

/* XXX: protobuf_c_data_buffer_append_repeated_data() is UNIMPLEMENTED */
void     protobuf_c_data_buffer_append_repeated_data(ProtobufCDataBuffer    *buffer, 
                                         const void   *data_to_repeat,
                                         size_t        data_length,
                                         size_t        count);


void     protobuf_c_data_buffer_append_string0      (ProtobufCDataBuffer    *buffer,
                                         const char   *string);


/* Take all the contents from src and append
 * them to dst, leaving src empty.
 */
size_t   protobuf_c_data_buffer_drain               (ProtobufCDataBuffer    *dst,
                                         ProtobufCDataBuffer    *src);

/* Like `drain', but only transfers some of the data. */
size_t   protobuf_c_data_buffer_transfer            (ProtobufCDataBuffer    *dst,
                                          ProtobufCDataBuffer    *src,
					 size_t        max_transfer);

/* file-descriptor mucking */
int      protobuf_c_data_buffer_writev              (ProtobufCDataBuffer       *read_from,
                                         int              fd);
int      protobuf_c_data_buffer_writev_len          (ProtobufCDataBuffer       *read_from,
                                         int              fd,
					 size_t           max_bytes);
int      protobuf_c_data_buffer_read_in_fd          (ProtobufCDataBuffer       *write_to,
                                         int              read_from);

/* This deallocates memory used by the buffer-- you are responsible
 * for the allocation and deallocation of the ProtobufCDataBuffer itself. */
void     protobuf_c_data_buffer_destruct            (ProtobufCDataBuffer    *to_destroy);

/* Free all unused buffer fragments. */
void     protobuf_c_data_buffer_cleanup_recycling_bin ();

#endif