summaryrefslogtreecommitdiff
path: root/libs/libcurl/src/gopher.c
blob: c48098f7540f5ffb2e75846bf52c4312b8647973 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
/***************************************************************************
 *                                  _   _ ____  _
 *  Project                     ___| | | |  _ \| |
 *                             / __| | | | |_) | |
 *                            | (__| |_| |  _ <| |___
 *                             \___|\___/|_| \_\_____|
 *
 * Copyright (C) 1998 - 2020, Daniel Stenberg, <daniel@haxx.se>, et al.
 *
 * This software is licensed as described in the file COPYING, which
 * you should have received as part of this distribution. The terms
 * are also available at https://curl.haxx.se/docs/copyright.html.
 *
 * 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 COPYING file.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 ***************************************************************************/

#include "curl_setup.h"

#ifndef CURL_DISABLE_GOPHER

#include "urldata.h"
#include <curl/curl.h>
#include "transfer.h"
#include "sendf.h"
#include "connect.h"
#include "progress.h"
#include "gopher.h"
#include "select.h"
#include "strdup.h"
#include "url.h"
#include "escape.h"
#include "warnless.h"
#include "curl_printf.h"
#include "curl_memory.h"
/* The last #include file should be: */
#include "memdebug.h"

/*
 * Forward declarations.
 */

static CURLcode gopher_do(struct connectdata *conn, bool *done);

/*
 * Gopher protocol handler.
 * This is also a nice simple template to build off for simple
 * connect-command-download protocols.
 */

const struct Curl_handler Curl_handler_gopher = {
  "GOPHER",                             /* scheme */
  ZERO_NULL,                            /* setup_connection */
  gopher_do,                            /* do_it */
  ZERO_NULL,                            /* done */
  ZERO_NULL,                            /* do_more */
  ZERO_NULL,                            /* connect_it */
  ZERO_NULL,                            /* connecting */
  ZERO_NULL,                            /* doing */
  ZERO_NULL,                            /* proto_getsock */
  ZERO_NULL,                            /* doing_getsock */
  ZERO_NULL,                            /* domore_getsock */
  ZERO_NULL,                            /* perform_getsock */
  ZERO_NULL,                            /* disconnect */
  ZERO_NULL,                            /* readwrite */
  ZERO_NULL,                            /* connection_check */
  PORT_GOPHER,                          /* defport */
  CURLPROTO_GOPHER,                     /* protocol */
  PROTOPT_NONE                          /* flags */
};

static CURLcode gopher_do(struct connectdata *conn, bool *done)
{
  CURLcode result = CURLE_OK;
  struct Curl_easy *data = conn->data;
  curl_socket_t sockfd = conn->sock[FIRSTSOCKET];
  char *gopherpath;
  char *path = data->state.up.path;
  char *query = data->state.up.query;
  char *sel = NULL;
  char *sel_org = NULL;
  timediff_t timeout_ms;
  ssize_t amount, k;
  size_t len;
  int what;

  *done = TRUE; /* unconditionally */

  /* path is guaranteed non-NULL */
  DEBUGASSERT(path);

  if(query)
    gopherpath = aprintf("%s?%s", path, query);
  else
    gopherpath = strdup(path);

  if(!gopherpath)
    return CURLE_OUT_OF_MEMORY;

  /* Create selector. Degenerate cases: / and /1 => convert to "" */
  if(strlen(gopherpath) <= 2) {
    sel = (char *)"";
    len = strlen(sel);
    free(gopherpath);
  }
  else {
    char *newp;

    /* Otherwise, drop / and the first character (i.e., item type) ... */
    newp = gopherpath;
    newp += 2;

    /* ... and finally unescape */
    result = Curl_urldecode(data, newp, 0, &sel, &len, FALSE);
    free(gopherpath);
    if(result)
      return result;
    sel_org = sel;
  }

  /* We use Curl_write instead of Curl_sendf to make sure the entire buffer is
     sent, which could be sizeable with long selectors. */
  k = curlx_uztosz(len);

  for(;;) {
    result = Curl_write(conn, sockfd, sel, k, &amount);
    if(!result) { /* Which may not have written it all! */
      result = Curl_client_write(conn, CLIENTWRITE_HEADER, sel, amount);
      if(result)
        break;

      k -= amount;
      sel += amount;
      if(k < 1)
        break; /* but it did write it all */
    }
    else
      break;

    timeout_ms = Curl_timeleft(conn->data, NULL, FALSE);
    if(timeout_ms < 0) {
      result = CURLE_OPERATION_TIMEDOUT;
      break;
    }
    if(!timeout_ms)
      timeout_ms = TIMEDIFF_T_MAX;

    /* Don't busyloop. The entire loop thing is a work-around as it causes a
       BLOCKING behavior which is a NO-NO. This function should rather be
       split up in a do and a doing piece where the pieces that aren't
       possible to send now will be sent in the doing function repeatedly
       until the entire request is sent.
    */
    what = SOCKET_WRITABLE(sockfd, timeout_ms);
    if(what < 0) {
      result = CURLE_SEND_ERROR;
      break;
    }
    else if(!what) {
      result = CURLE_OPERATION_TIMEDOUT;
      break;
    }
  }

  free(sel_org);

  if(!result)
    /* We can use Curl_sendf to send the terminal \r\n relatively safely and
       save allocing another string/doing another _write loop. */
    result = Curl_sendf(sockfd, conn, "\r\n");
  if(result) {
    failf(data, "Failed sending Gopher request");
    return result;
  }
  result = Curl_client_write(conn, CLIENTWRITE_HEADER, (char *)"\r\n", 2);
  if(result)
    return result;

  Curl_setup_transfer(data, FIRSTSOCKET, -1, FALSE, -1);
  return CURLE_OK;
}
#endif /*CURL_DISABLE_GOPHER*/