curl/lib/http_chunks.h

#ifndef __HTTP_CHUNKS_H
#define __HTTP_CHUNKS_H
/*****************************************************************************
 *                                  _   _ ____  _     
 *  Project                     ___| | | |  _ \| |    
 *                             / __| | | | |_) | |    
 *                            | (__| |_| |  _ <| |___ 
 *                             \___|\___/|_| \_\_____|
 *
 * Copyright (C) 2001, Daniel Stenberg, <daniel@haxx.se>, et al.
 *
 * In order to be useful for every potential user, curl and libcurl are
 * dual-licensed under the MPL and the MIT/X-derivate licenses.
 *
 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
 * copies of the Software, and permit persons to whom the Software is
 * furnished to do so, under the terms of the MPL or the MIT/X-derivate
 * licenses. You may pick one of these licenses.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 * $Id$
 *****************************************************************************/
/*
 * The longest possible hexadecimal number we support in a chunked transfer.
 * Weird enough, RFC2616 doesn't set a maximum size! Since we use strtoul()
 * to convert it, we "only" support 2^32 bytes chunk data.
 */
#define MAXNUM_SIZE 16

typedef enum {
  CHUNK_FIRST, /* never use */

  /* In this we await and buffer all hexadecimal digits until we get one
     that isn't a hexadecimal digit. When done, we go POSTHEX */
  CHUNK_HEX,

  /* We have received the hexadecimal digit and we eat all characters until
     we get a CRLF pair. When we see a CR we go to the CR state. */
  CHUNK_POSTHEX,

  /* A single CR has been found and we should get a LF right away in this
     state or we go back to POSTHEX. When LF is received, we go to DATA.
     If the size given was zero, we set state to STOP and return. */
  CHUNK_CR,

  /* We eat the amount of data specified. When done, we move on to the
     POST_CR state. */
  CHUNK_DATA,

  /* POSTCR should get a CR and nothing else, then move to POSTLF */
  CHUNK_POSTCR,

  /* POSTLF should get a LF and nothing else, then move back to HEX as
     the CRLF combination marks the end of a chunk */
  CHUNK_POSTLF,

  /* This is mainly used to really mark that we're out of the game.
     NOTE: that there's a 'dataleft' field in the struct that will tell how
     many bytes that were not passed to the client in the end of the last
     buffer! */
  CHUNK_STOP,

  CHUNK_LAST /* never use */
} ChunkyState;

typedef enum {
  CHUNKE_STOP = -1,
  CHUNKE_OK = 0,
  CHUNKE_TOO_LONG_HEX = 1,
  CHUNKE_ILLEGAL_HEX,
  CHUNKE_BAD_CHUNK,
  CHUNKE_WRITE_ERROR,
  CHUNKE_STATE_ERROR,
  CHUNKE_LAST
} CHUNKcode;

struct Curl_chunker {
  char hexbuffer[ MAXNUM_SIZE + 1];
  int hexindex;
  ChunkyState state;
  size_t datasize;
  size_t dataleft; /* untouched data amount at the end of the last buffer */
};

#endif