xref: /third_party/curl/lib/curl_range.c (revision 13498266)
1/***************************************************************************
2 *                                  _   _ ____  _
3 *  Project                     ___| | | |  _ \| |
4 *                             / __| | | | |_) | |
5 *                            | (__| |_| |  _ <| |___
6 *                             \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
9 *
10 * This software is licensed as described in the file COPYING, which
11 * you should have received as part of this distribution. The terms
12 * are also available at https://curl.se/docs/copyright.html.
13 *
14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15 * copies of the Software, and permit persons to whom the Software is
16 * furnished to do so, under the terms of the COPYING file.
17 *
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
20 *
21 * SPDX-License-Identifier: curl
22 *
23 ***************************************************************************/
24
25#include "curl_setup.h"
26#include <curl/curl.h>
27#include "curl_range.h"
28#include "sendf.h"
29#include "strtoofft.h"
30
31/* Only include this function if one or more of FTP, FILE are enabled. */
32#if !defined(CURL_DISABLE_FTP) || !defined(CURL_DISABLE_FILE)
33
34 /*
35  Check if this is a range download, and if so, set the internal variables
36  properly.
37 */
38CURLcode Curl_range(struct Curl_easy *data)
39{
40  curl_off_t from, to;
41  char *ptr;
42  char *ptr2;
43
44  if(data->state.use_range && data->state.range) {
45    CURLofft from_t;
46    CURLofft to_t;
47    from_t = curlx_strtoofft(data->state.range, &ptr, 10, &from);
48    if(from_t == CURL_OFFT_FLOW)
49      return CURLE_RANGE_ERROR;
50    while(*ptr && (ISBLANK(*ptr) || (*ptr == '-')))
51      ptr++;
52    to_t = curlx_strtoofft(ptr, &ptr2, 10, &to);
53    if(to_t == CURL_OFFT_FLOW)
54      return CURLE_RANGE_ERROR;
55    if((to_t == CURL_OFFT_INVAL) && !from_t) {
56      /* X - */
57      data->state.resume_from = from;
58      DEBUGF(infof(data, "RANGE %" CURL_FORMAT_CURL_OFF_T " to end of file",
59                   from));
60    }
61    else if((from_t == CURL_OFFT_INVAL) && !to_t) {
62      /* -Y */
63      data->req.maxdownload = to;
64      data->state.resume_from = -to;
65      DEBUGF(infof(data, "RANGE the last %" CURL_FORMAT_CURL_OFF_T " bytes",
66                   to));
67    }
68    else {
69      /* X-Y */
70      curl_off_t totalsize;
71
72      /* Ensure the range is sensible - to should follow from. */
73      if(from > to)
74        return CURLE_RANGE_ERROR;
75
76      totalsize = to - from;
77      if(totalsize == CURL_OFF_T_MAX)
78        return CURLE_RANGE_ERROR;
79
80      data->req.maxdownload = totalsize + 1; /* include last byte */
81      data->state.resume_from = from;
82      DEBUGF(infof(data, "RANGE from %" CURL_FORMAT_CURL_OFF_T
83                   " getting %" CURL_FORMAT_CURL_OFF_T " bytes",
84                   from, data->req.maxdownload));
85    }
86    DEBUGF(infof(data, "range-download from %" CURL_FORMAT_CURL_OFF_T
87                 " to %" CURL_FORMAT_CURL_OFF_T ", totally %"
88                 CURL_FORMAT_CURL_OFF_T " bytes",
89                 from, to, data->req.maxdownload));
90  }
91  else
92    data->req.maxdownload = -1;
93  return CURLE_OK;
94}
95
96#endif
97