C++ Curl_convert_from_network函数代码示例

/*
 * Curl_urldecode() URL decodes the given string.
 *
 * Optionally detects control characters (byte codes lower than 32) in the
 * data and rejects such data.
 *
 * Returns a pointer to a malloced string in *ostring with length given in
 * *olen. If length == 0, the length is assumed to be strlen(string).
 *
 */
CURLcode Curl_urldecode(struct SessionHandle *data,
                        const char *string, size_t length,
                        char **ostring, size_t *olen,
                        bool reject_ctrl)
{
  size_t alloc = (length?length:strlen(string))+1;
  char *ns = malloc(alloc);
  unsigned char in;
  size_t strindex=0;
  unsigned long hex;
  CURLcode res;

  if(!ns)
    return CURLE_OUT_OF_MEMORY;

  while(--alloc > 0) {
    in = *string;
    if(('%' == in) && (alloc > 2) &&
       ISXDIGIT(string[1]) && ISXDIGIT(string[2])) {
      /* this is two hexadecimal digits following a '%' */
      char hexstr[3];
      char *ptr;
      hexstr[0] = string[1];
      hexstr[1] = string[2];
      hexstr[2] = 0;

      hex = strtoul(hexstr, &ptr, 16);

      in = curlx_ultouc(hex); /* this long is never bigger than 255 anyway */

      res = Curl_convert_from_network(data, &in, 1);
      if(res) {
        /* Curl_convert_from_network calls failf if unsuccessful */
        free(ns);
        return res;
      }

      string+=2;
      alloc-=2;
    }
    if(reject_ctrl && (in < 0x20)) {
      free(ns);
      return CURLE_URL_MALFORMAT;
    }

    ns[strindex++] = in;
    string++;
  }
  ns[strindex]=0; /* terminate it */

  if(olen)
    /* store output size */
    *olen = strindex;

  if(ostring)
    /* store output string */
    *ostring = ns;

  return CURLE_OK;
}

/* Curl_client_write() sends data to the write callback(s)

   The bit pattern defines to what "streams" to write to. Body and/or header.
   The defines are in sendf.h of course.

   If CURL_DO_LINEEND_CONV is enabled, data is converted IN PLACE to the
   local character encoding.  This is a problem and should be changed in
   the future to leave the original data alone.
 */
CURLcode Curl_client_write(struct connectdata *conn,
                           int type,
                           char *ptr,
                           size_t len)
{
  struct Curl_easy *data = conn->data;

  if(0 == len)
    len = strlen(ptr);

  DEBUGASSERT(type <= 3);

  /* FTP data may need conversion. */
  if((type & CLIENTWRITE_BODY) &&
    (conn->handler->protocol & PROTO_FAMILY_FTP) &&
    conn->proto.ftpc.transfertype == 'A') {
    /* convert from the network encoding */
    CURLcode result = Curl_convert_from_network(data, ptr, len);
    /* Curl_convert_from_network calls failf if unsuccessful */
    if(result)
      return result;

#ifdef CURL_DO_LINEEND_CONV
    /* convert end-of-line markers */
    len = convert_lineends(data, ptr, len);
#endif /* CURL_DO_LINEEND_CONV */
    }

  return chop_write(conn, type, ptr, len);
}

/*
 * Unescapes the given URL escaped string of given length. Returns a
 * pointer to a malloced string with length given in *olen.
 * If length == 0, the length is assumed to be strlen(string).
 * If olen == NULL, no output length is stored.
 */
char *curl_easy_unescape(CURL *handle, const char *string, int length,
                         int *olen)
{
  int alloc = (length?length:(int)strlen(string))+1;
  char *ns = malloc(alloc);
  unsigned char in;
  int strindex=0;
  long hex;

#ifndef CURL_DOES_CONVERSIONS
  /* avoid compiler warnings */
  (void)handle;
#endif
  if( !ns )
    return NULL;

  while(--alloc > 0) {
    in = *string;
    if(('%' == in) && ISXDIGIT(string[1]) && ISXDIGIT(string[2])) {
      /* this is two hexadecimal digits following a '%' */
      char hexstr[3];
      char *ptr;
      hexstr[0] = string[1];
      hexstr[1] = string[2];
      hexstr[2] = 0;

      hex = strtol(hexstr, &ptr, 16);

      in = (unsigned char)hex; /* this long is never bigger than 255 anyway */

#ifdef CURL_DOES_CONVERSIONS
/* escape sequences are always in ASCII so convert them on non-ASCII hosts */
      if(!handle ||
          (Curl_convert_from_network(handle, &in, 1) != CURLE_OK)) {
        /* Curl_convert_from_network calls failf if unsuccessful */
        free(ns);
        return NULL;
      }
#endif /* CURL_DOES_CONVERSIONS */

      string+=2;
      alloc-=2;
    }

    ns[strindex++] = in;
    string++;
  }
  ns[strindex]=0; /* terminate it */

  if(olen)
    /* store output size */
    *olen = strindex;
  return ns;
}

/*
 * Unescapes the given URL escaped string of given length. Returns a
 * pointer to a malloced string with length given in *olen.
 * If length == 0, the length is assumed to be strlen(string).
 * If olen == NULL, no output length is stored.
 */
char *curl_easy_unescape(CURL *handle, const char *string, int length,
                         int *olen)
{
  int alloc = (length?length:(int)strlen(string))+1;
  char *ns = malloc(alloc);
  unsigned char in;
  int strindex=0;
  unsigned long hex;
  CURLcode res;

  if(!ns)
    return NULL;

  while(--alloc > 0) {
    in = *string;
    if(('%' == in) && ISXDIGIT(string[1]) && ISXDIGIT(string[2])) {
      /* this is two hexadecimal digits following a '%' */
      char hexstr[3];
      char *ptr;
      hexstr[0] = string[1];
      hexstr[1] = string[2];
      hexstr[2] = 0;

      hex = strtoul(hexstr, &ptr, 16);

      in = curlx_ultouc(hex); /* this long is never bigger than 255 anyway */

      res = Curl_convert_from_network(handle, &in, 1);
      if(res) {
        /* Curl_convert_from_network calls failf if unsuccessful */
        free(ns);
        return NULL;
      }

      string+=2;
      alloc-=2;
    }

    ns[strindex++] = in;
    string++;
  }
  ns[strindex]=0; /* terminate it */

  if(olen)
    /* store output size */
    *olen = strindex;
  return ns;
}

//.........这里部分代码省略.........
                  keepon = FALSE;
                  break;
                }
              }
              else {
                /* chunked-encoded body, so we need to do the chunked dance
                   properly to know when the end of the body is reached */
                CHUNKcode r;
                ssize_t tookcareof=0;

                /* now parse the chunked piece of data so that we can
                   properly tell when the stream ends */
                r = Curl_httpchunk_read(conn, ptr, gotbytes, &tookcareof);
                if(r == CHUNKE_STOP) {
                  /* we're done reading chunks! */
                  infof(data, "chunk reading DONE\n");
                  keepon = FALSE;
                  /* we did the full CONNECT treatment, go COMPLETE */
                  conn->tunnel_state[sockindex] = TUNNEL_COMPLETE;
                }
                else
                  infof(data, "Read %zd bytes of chunk, continue\n",
                        tookcareof);
              }
            }
            else
              for(i = 0; i < gotbytes; ptr++, i++) {
                perline++; /* amount of bytes in this line so far */
                if(*ptr == 0x0a) {
                  char letter;
                  int writetype;

                  /* convert from the network encoding */
                  result = Curl_convert_from_network(data, line_start,
                                                     perline);
                  /* Curl_convert_from_network calls failf if unsuccessful */
                  if(result)
                    return result;

                  /* output debug if that is requested */
                  if(data->set.verbose)
                    Curl_debug(data, CURLINFO_HEADER_IN,
                               line_start, (size_t)perline, conn);

                  /* send the header to the callback */
                  writetype = CLIENTWRITE_HEADER;
                  if(data->set.include_header)
                    writetype |= CLIENTWRITE_BODY;

                  result = Curl_client_write(conn, writetype, line_start,
                                             perline);

                  data->info.header_size += (long)perline;
                  data->req.headerbytecount += (long)perline;

                  if(result)
                    return result;

                  /* Newlines are CRLF, so the CR is ignored as the line isn't
                     really terminated until the LF comes. Treat a following CR
                     as end-of-headers as well.*/

                  if(('\r' == line_start[0]) ||
                     ('\n' == line_start[0])) {
                    /* end of response-headers from the proxy */
                    nread = 0; /* make next read start over in the read

/*
 * Curl_pp_readresp()
 *
 * Reads a piece of a server response.
 */
CURLcode Curl_pp_readresp(curl_socket_t sockfd,
                          struct pingpong *pp,
                          int *code, /* return the server code if done */
                          size_t *size) /* size of the response */
{
  ssize_t perline; /* count bytes per line */
  bool keepon=TRUE;
  ssize_t gotbytes;
  char *ptr;
  struct connectdata *conn = pp->conn;
  struct SessionHandle *data = conn->data;
  char * const buf = data->state.buffer;
  CURLcode result = CURLE_OK;

  *code = 0; /* 0 for errors or not done */
  *size = 0;

  ptr=buf + pp->nread_resp;

  /* number of bytes in the current line, so far */
  perline = (ssize_t)(ptr-pp->linestart_resp);

  keepon=TRUE;

  while((pp->nread_resp<BUFSIZE) && (keepon && !result)) {

    if(pp->cache) {
      /* we had data in the "cache", copy that instead of doing an actual
       * read
       *
       * ftp->cache_size is cast to int here.  This should be safe,
       * because it would have been populated with something of size
       * int to begin with, even though its datatype may be larger
       * than an int.
       */
      DEBUGASSERT((ptr+pp->cache_size) <= (buf+BUFSIZE+1));
      memcpy(ptr, pp->cache, pp->cache_size);
      gotbytes = pp->cache_size;
      free(pp->cache);    /* free the cache */
      pp->cache = NULL;   /* clear the pointer */
      pp->cache_size = 0; /* zero the size just in case */
    }
    else {
      int res;
#if defined(HAVE_KRB4) || defined(HAVE_GSSAPI)
      enum protection_level prot = conn->data_prot;

      conn->data_prot = 0;
#endif
      DEBUGASSERT((ptr+BUFSIZE-pp->nread_resp) <= (buf+BUFSIZE+1));
      res = Curl_read(conn, sockfd, ptr, BUFSIZE-pp->nread_resp,
                      &gotbytes);
#if defined(HAVE_KRB4) || defined(HAVE_GSSAPI)
      conn->data_prot = prot;
#endif
      if(res < 0)
        /* EWOULDBLOCK */
        return CURLE_OK; /* return */

#ifdef CURL_DOES_CONVERSIONS
      if((res == CURLE_OK) && (gotbytes > 0)) {
        /* convert from the network encoding */
        res = Curl_convert_from_network(data, ptr, gotbytes);
        /* Curl_convert_from_network calls failf if unsuccessful */
      }
#endif /* CURL_DOES_CONVERSIONS */

      if(CURLE_OK != res) {
        result = (CURLcode)res; /* Set outer result variable to this error. */
        keepon = FALSE;
      }
    }

    if(!keepon)
      ;
    else if(gotbytes <= 0) {
      keepon = FALSE;
      result = CURLE_RECV_ERROR;
      failf(data, "FTP response reading failed");
    }
    else {
      /* we got a whole chunk of data, which can be anything from one
       * byte to a set of lines and possible just a piece of the last
       * line */
      ssize_t i;
      ssize_t clipamount = 0;
      bool restart = FALSE;

      data->req.headerbytecount += (long)gotbytes;

      pp->nread_resp += gotbytes;
      for(i = 0; i < gotbytes; ptr++, i++) {
        perline++;
        if(*ptr=='\n') {
          /* a newline is CRLF in ftp-talk, so the CR is ignored as
//.........这里部分代码省略.........

/*
 * chunk_read() returns a OK for normal operations, or a positive return code
 * for errors. STOP means this sequence of chunks is complete.  The 'wrote'
 * argument is set to tell the caller how many bytes we actually passed to the
 * client (for byte-counting and whatever).
 *
 * The states and the state-machine is further explained in the header file.
 *
 * This function always uses ASCII hex values to accommodate non-ASCII hosts.
 * For example, 0x0d and 0x0a are used instead of '\r' and '\n'.
 */
CHUNKcode Curl_httpchunk_read(struct connectdata *conn,
                              char *datap,
                              ssize_t datalen,
                              ssize_t *wrotep)
{
  CURLcode result=CURLE_OK;
  struct SessionHandle *data = conn->data;
  struct Curl_chunker *ch = &conn->chunk;
  struct SingleRequest *k = &data->req;
  size_t piece;
  size_t length = (size_t)datalen;
  size_t *wrote = (size_t *)wrotep;

  *wrote = 0; /* nothing's written yet */

  /* the original data is written to the client, but we go on with the
     chunk read process, to properly calculate the content length*/
  if(data->set.http_te_skip && !k->ignorebody) {
    result = Curl_client_write(conn, CLIENTWRITE_BODY, datap, datalen);
    if(result)
      return CHUNKE_WRITE_ERROR;
  }

  while(length) {
    switch(ch->state) {
    case CHUNK_HEX:
      if(Curl_isxdigit(*datap)) {
        if(ch->hexindex < MAXNUM_SIZE) {
          ch->hexbuffer[ch->hexindex] = *datap;
          datap++;
          length--;
          ch->hexindex++;
        }
        else {
          return CHUNKE_TOO_LONG_HEX; /* longer hex than we support */
        }
      }
      else {
        if(0 == ch->hexindex) {
          /* This is illegal data, we received junk where we expected
             a hexadecimal digit. */
          return CHUNKE_ILLEGAL_HEX;
        }
        /* length and datap are unmodified */
        ch->hexbuffer[ch->hexindex]=0;
#ifdef CURL_DOES_CONVERSIONS
        /* convert to host encoding before calling strtoul */
        result = Curl_convert_from_network(conn->data,
                                           ch->hexbuffer,
                                           ch->hexindex);
        if(result != CURLE_OK) {
          /* Curl_convert_from_network calls failf if unsuccessful */
          /* Treat it as a bad hex character */
          return(CHUNKE_ILLEGAL_HEX);
        }
#endif /* CURL_DOES_CONVERSIONS */
        ch->datasize=strtoul(ch->hexbuffer, NULL, 16);
        ch->state = CHUNK_POSTHEX;
      }
      break;

    case CHUNK_POSTHEX:
      /* In this state, we're waiting for CRLF to arrive. We support
         this to allow so called chunk-extensions to show up here
         before the CRLF comes. */
      if(*datap == 0x0d)
        ch->state = CHUNK_CR;
      length--;
      datap++;
      break;

    case CHUNK_CR:
      /* waiting for the LF */
      if(*datap == 0x0a) {
        /* we're now expecting data to come, unless size was zero! */
        if(0 == ch->datasize) {
          ch->state = CHUNK_TRAILER; /* now check for trailers */
          conn->trlPos=0;
        }
        else {
          ch->state = CHUNK_DATA;
        }
      }
      else
        /* previously we got a fake CR, go back to CR waiting! */
        ch->state = CHUNK_CR;
      datap++;
      length--;
      break;
//.........这里部分代码省略.........

/* return 0 on success */
static int showit(struct SessionHandle *data, curl_infotype type,
                  char *ptr, size_t size)
{
  static const char s_infotype[CURLINFO_END][3] = {
    "* ", "< ", "> ", "{ ", "} ", "{ ", "} " };

#ifdef CURL_DOES_CONVERSIONS
  char buf[BUFSIZE+1];
  size_t conv_size = 0;

  switch(type) {
  case CURLINFO_HEADER_OUT:
    /* assume output headers are ASCII */
    /* copy the data into my buffer so the original is unchanged */
    if(size > BUFSIZE) {
      size = BUFSIZE; /* truncate if necessary */
      buf[BUFSIZE] = '\0';
    }
    conv_size = size;
    memcpy(buf, ptr, size);
    /* Special processing is needed for this block if it
     * contains both headers and data (separated by CRLFCRLF).
     * We want to convert just the headers, leaving the data as-is.
     */
    if(size > 4) {
      size_t i;
      for(i = 0; i < size-4; i++) {
        if(memcmp(&buf[i], "\x0d\x0a\x0d\x0a", 4) == 0) {
          /* convert everything through this CRLFCRLF but no further */
          conv_size = i + 4;
          break;
        }
      }
    }

    Curl_convert_from_network(data, buf, conv_size);
    /* Curl_convert_from_network calls failf if unsuccessful */
    /* we might as well continue even if it fails...   */
    ptr = buf; /* switch pointer to use my buffer instead */
    break;
  default:
    /* leave everything else as-is */
    break;
  }
#endif /* CURL_DOES_CONVERSIONS */

  if(data->set.fdebug)
    return (*data->set.fdebug)(data, type, ptr, size,
                               data->set.debugdata);

  switch(type) {
  case CURLINFO_TEXT:
  case CURLINFO_HEADER_OUT:
  case CURLINFO_HEADER_IN:
    fwrite(s_infotype[type], 2, 1, data->set.err);
    fwrite(ptr, size, 1, data->set.err);
#ifdef CURL_DOES_CONVERSIONS
    if(size != conv_size) {
      /* we had untranslated data so we need an explicit newline */
      fwrite("\n", 1, 1, data->set.err);
    }
#endif
    break;
  default: /* nada */
    break;
  }
  return 0;
}

/* Curl_client_write() sends data to the write callback(s)

   The bit pattern defines to what "streams" to write to. Body and/or header.
   The defines are in sendf.h of course.

   If CURL_DO_LINEEND_CONV is enabled, data is converted IN PLACE to the
   local character encoding.  This is a problem and should be changed in
   the future to leave the original data alone.
 */
CURLcode Curl_client_write(struct connectdata *conn,
                           int type,
                           char *ptr,
                           size_t len)
{
  struct SessionHandle *data = conn->data;
  size_t wrote;

  if(0 == len)
    len = strlen(ptr);

  /* If reading is actually paused, we're forced to append this chunk of data
     to the already held data, but only if it is the same type as otherwise it
     can't work and it'll return error instead. */
  if(data->req.keepon & KEEP_RECV_PAUSE) {
    size_t newlen;
    char *newptr;
    if(type != data->state.tempwritetype)
      /* major internal confusion */
      return CURLE_RECV_ERROR;

    DEBUGASSERT(data->state.tempwrite);

    /* figure out the new size of the data to save */
    newlen = len + data->state.tempwritesize;
    /* allocate the new memory area */
    newptr = realloc(data->state.tempwrite, newlen);
    if(!newptr)
      return CURLE_OUT_OF_MEMORY;
    /* copy the new data to the end of the new area */
    memcpy(newptr + data->state.tempwritesize, ptr, len);
    /* update the pointer and the size */
    data->state.tempwrite = newptr;
    data->state.tempwritesize = newlen;

    return CURLE_OK;
  }

  if(type & CLIENTWRITE_BODY) {
    if((conn->handler->protocol&CURLPROTO_FTP) &&
       conn->proto.ftpc.transfertype == 'A') {
      /* convert from the network encoding */
      size_t rc = Curl_convert_from_network(data, ptr, len);
      /* Curl_convert_from_network calls failf if unsuccessful */
      if(rc)
        return rc;

#ifdef CURL_DO_LINEEND_CONV
      /* convert end-of-line markers */
      len = convert_lineends(data, ptr, len);
#endif /* CURL_DO_LINEEND_CONV */
    }
    /* If the previous block of data ended with CR and this block of data is
       just a NL, then the length might be zero */
    if(len) {
      wrote = data->set.fwrite_func(ptr, 1, len, data->set.out);
    }
    else {
      wrote = len;
    }

    if(CURL_WRITEFUNC_PAUSE == wrote)
      return pausewrite(data, type, ptr, len);

    if(wrote != len) {
      failf(data, "Failed writing body (%zu != %zu)", wrote, len);
      return CURLE_WRITE_ERROR;
    }
  }

  if((type & CLIENTWRITE_HEADER) &&
     (data->set.fwrite_header || data->set.writeheader) ) {
    /*
     * Write headers to the same callback or to the especially setup
     * header callback function (added after version 7.7.1).
     */
    curl_write_callback writeit=
      data->set.fwrite_header?data->set.fwrite_header:data->set.fwrite_func;

    /* Note: The header is in the host encoding
       regardless of the ftp transfer mode (ASCII/Image) */

    wrote = writeit(ptr, 1, len, data->set.writeheader);
    if(CURL_WRITEFUNC_PAUSE == wrote)
      /* here we pass in the HEADER bit only since if this was body as well
         then it was passed already and clearly that didn't trigger the pause,
         so this is saved for later with the HEADER bit only */
      return pausewrite(data, CLIENTWRITE_HEADER, ptr, len);

    if(wrote != len) {
      failf (data, "Failed writing header");
//.........这里部分代码省略.........

//.........这里部分代码省略.........
              s->tunnel_state = TUNNEL_COMPLETE;
              break;
            }
          }
          else {
            /* chunked-encoded body, so we need to do the chunked dance
               properly to know when the end of the body is reached */
            CHUNKcode r;
            ssize_t tookcareof = 0;

            /* now parse the chunked piece of data so that we can
               properly tell when the stream ends */
            r = Curl_httpchunk_read(conn, s->ptr, 1, &tookcareof);
            if(r == CHUNKE_STOP) {
              /* we're done reading chunks! */
              infof(data, "chunk reading DONE\n");
              s->keepon = FALSE;
              /* we did the full CONNECT treatment, go COMPLETE */
              s->tunnel_state = TUNNEL_COMPLETE;
            }
          }
          continue;
        }

        s->perline++; /* amount of bytes in this line so far */

        /* if this is not the end of a header line then continue */
        if(*s->ptr != 0x0a) {
          s->ptr++;
          continue;
        }

        /* convert from the network encoding */
        result = Curl_convert_from_network(data, s->line_start,
                                           (size_t)s->perline);
        /* Curl_convert_from_network calls failf if unsuccessful */
        if(result)
          return result;

        /* output debug if that is requested */
        if(data->set.verbose)
          Curl_debug(data, CURLINFO_HEADER_IN,
                     s->line_start, (size_t)s->perline);

        if(!data->set.suppress_connect_headers) {
          /* send the header to the callback */
          int writetype = CLIENTWRITE_HEADER;
          if(data->set.include_header)
            writetype |= CLIENTWRITE_BODY;

          result = Curl_client_write(conn, writetype,
                                     s->line_start, s->perline);
          if(result)
            return result;
        }

        data->info.header_size += (long)s->perline;
        data->req.headerbytecount += (long)s->perline;

        /* Newlines are CRLF, so the CR is ignored as the line isn't
           really terminated until the LF comes. Treat a following CR
           as end-of-headers as well.*/

        if(('\r' == s->line_start[0]) ||
           ('\n' == s->line_start[0])) {
          /* end of response-headers from the proxy */

/* client_write() sends data to the write callback(s)

   The bit pattern defines to what "streams" to write to. Body and/or header.
   The defines are in sendf.h of course.
 */
CURLcode Curl_client_write(struct connectdata *conn,
                           int type,
                           char *ptr,
                           size_t len)
{
  struct SessionHandle *data = conn->data;
  size_t wrote;

  if (data->state.cancelled) {
      /* We just suck everything into a black hole */
      return CURLE_OK;
  }

  if(0 == len)
    len = strlen(ptr);

  if(type & CLIENTWRITE_BODY) {
    if((conn->protocol&PROT_FTP) && conn->proto.ftpc.transfertype == 'A') {
#ifdef CURL_DOES_CONVERSIONS
      /* convert from the network encoding */
      size_t rc;
      rc = Curl_convert_from_network(data, ptr, len);
      /* Curl_convert_from_network calls failf if unsuccessful */
      if(rc != CURLE_OK)
        return rc;
#endif /* CURL_DOES_CONVERSIONS */

#ifdef CURL_DO_LINEEND_CONV
      /* convert end-of-line markers */
      len = convert_lineends(data, ptr, len);
#endif /* CURL_DO_LINEEND_CONV */
    }
    /* If the previous block of data ended with CR and this block of data is
       just a NL, then the length might be zero */
    if (len) {
      wrote = data->set.fwrite(ptr, 1, len, data->set.out);
    }
    else {
      wrote = len;
    }

    if(wrote != len) {
      failf (data, "Failed writing body");
      return CURLE_WRITE_ERROR;
    }
  }

  if((type & CLIENTWRITE_HEADER) &&
     (data->set.fwrite_header || data->set.writeheader) ) {
    /*
     * Write headers to the same callback or to the especially setup
     * header callback function (added after version 7.7.1).
     */
    curl_write_callback writeit=
      data->set.fwrite_header?data->set.fwrite_header:data->set.fwrite;

    /* Note: The header is in the host encoding
       regardless of the ftp transfer mode (ASCII/Image) */

    wrote = writeit(ptr, 1, len, data->set.writeheader);
    if(wrote != len) {
      failf (data, "Failed writing header");
      return CURLE_WRITE_ERROR;
    }
  }

  return CURLE_OK;
}

/*
 * chunk_read() returns a OK for normal operations, or a positive return code
 * for errors. STOP means this sequence of chunks is complete.  The 'wrote'
 * argument is set to tell the caller how many bytes we actually passed to the
 * client (for byte-counting and whatever).
 *
 * The states and the state-machine is further explained in the header file.
 *
 * This function always uses ASCII hex values to accommodate non-ASCII hosts.
 * For example, 0x0d and 0x0a are used instead of '\r' and '\n'.
 */
CHUNKcode Curl_httpchunk_read(struct connectdata *conn,
                              char *datap,
                              ssize_t datalen,
                              ssize_t *wrotep)
{
  CURLcode result=CURLE_OK;
  struct SessionHandle *data = conn->data;
  struct Curl_chunker *ch = &data->reqdata.proto.http->chunk;
  struct Curl_transfer_keeper *k = &data->reqdata.keep;
  size_t piece;
  size_t length = (size_t)datalen;
  size_t *wrote = (size_t *)wrotep;

  *wrote = 0; /* nothing's written yet */

  /* the original data is written to the client, but we go on with the
     chunk read process, to properly calculate the content length*/
  if (data->set.http_te_skip && !k->ignorebody)
    Curl_client_write(conn, CLIENTWRITE_BODY, datap,datalen);

  while(length) {
    switch(ch->state) {
    case CHUNK_HEX:
       /* Check for an ASCII hex digit.
          We avoid the use of isxdigit to accommodate non-ASCII hosts. */
       if((*datap >= 0x30 && *datap <= 0x39)    /* 0-9 */
       || (*datap >= 0x41 && *datap <= 0x46)    /* A-F */
       || (*datap >= 0x61 && *datap <= 0x66)) { /* a-f */
        if(ch->hexindex < MAXNUM_SIZE) {
          ch->hexbuffer[ch->hexindex] = *datap;
          datap++;
          length--;
          ch->hexindex++;
        }
        else {
          return CHUNKE_TOO_LONG_HEX; /* longer hex than we support */
        }
      }
      else {
        if(0 == ch->hexindex) {
          /* This is illegal data, we received junk where we expected
             a hexadecimal digit. */
          return CHUNKE_ILLEGAL_HEX;
        }
        /* length and datap are unmodified */
        ch->hexbuffer[ch->hexindex]=0;
#ifdef CURL_DOES_CONVERSIONS
        /* convert to host encoding before calling strtoul */
        result = Curl_convert_from_network(conn->data,
                                           ch->hexbuffer,
                                           ch->hexindex);
        if(result != CURLE_OK) {
          /* Curl_convert_from_network calls failf if unsuccessful */
          /* Treat it as a bad hex character */
          return(CHUNKE_ILLEGAL_HEX);
        }
#endif /* CURL_DOES_CONVERSIONS */
        ch->datasize=strtoul(ch->hexbuffer, NULL, 16);
        ch->state = CHUNK_POSTHEX;
      }
      break;

    case CHUNK_POSTHEX:
      /* In this state, we're waiting for CRLF to arrive. We support
         this to allow so called chunk-extensions to show up here
         before the CRLF comes. */
      if(*datap == 0x0d)
        ch->state = CHUNK_CR;
      length--;
      datap++;
      break;

    case CHUNK_CR:
      /* waiting for the LF */
      if(*datap == 0x0a) {
        /* we're now expecting data to come, unless size was zero! */
        if(0 == ch->datasize) {
          if (conn->bits.trailerHdrPresent!=TRUE) {
            /* No Trailer: header found - revert to original Curl processing */
            ch->state = CHUNK_STOPCR;

            /* We need to increment the datap here since we bypass the
               increment below with the immediate break */
            length--;
            datap++;

            /* This is the final byte, continue to read the final CRLF */
            break;
          }
//.........这里部分代码省略.........

/* return 0 on success */
static int showit(struct Curl_easy *data, curl_infotype type,
                  char *ptr, size_t size)
{
  static const char s_infotype[CURLINFO_END][3] = {
    "* ", "< ", "> ", "{ ", "} ", "{ ", "} " };
  int rc = 0;

#ifdef CURL_DOES_CONVERSIONS
  char *buf = NULL;
  size_t conv_size = 0;

  switch(type) {
  case CURLINFO_HEADER_OUT:
    buf = Curl_memdup(ptr, size);
    if(!buf)
      return 1;
    conv_size = size;

    /* Special processing is needed for this block if it
     * contains both headers and data (separated by CRLFCRLF).
     * We want to convert just the headers, leaving the data as-is.
     */
    if(size > 4) {
      size_t i;
      for(i = 0; i < size-4; i++) {
        if(memcmp(&buf[i], "\x0d\x0a\x0d\x0a", 4) == 0) {
          /* convert everything through this CRLFCRLF but no further */
          conv_size = i + 4;
          break;
        }
      }
    }

    Curl_convert_from_network(data, buf, conv_size);
    /* Curl_convert_from_network calls failf if unsuccessful */
    /* we might as well continue even if it fails...   */
    ptr = buf; /* switch pointer to use my buffer instead */
    break;
  default:
    /* leave everything else as-is */
    break;
  }
#endif /* CURL_DOES_CONVERSIONS */

  if(data->set.fdebug) {
    Curl_set_in_callback(data, true);
    rc = (*data->set.fdebug)(data, type, ptr, size, data->set.debugdata);
    Curl_set_in_callback(data, false);
  }
  else {
    switch(type) {
    case CURLINFO_TEXT:
    case CURLINFO_HEADER_OUT:
    case CURLINFO_HEADER_IN:
      fwrite(s_infotype[type], 2, 1, data->set.err);
      fwrite(ptr, size, 1, data->set.err);
#ifdef CURL_DOES_CONVERSIONS
      if(size != conv_size) {
        /* we had untranslated data so we need an explicit newline */
        fwrite("\n", 1, 1, data->set.err);
      }
#endif
      break;
    default: /* nada */
      break;
    }
  }
#ifdef CURL_DOES_CONVERSIONS
  free(buf);
#endif
  return rc;
}