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 /* <DESC>
25 * HTTP/2 download pausing
26 * </DESC>
27 */
28 /* This is based on the PoC client of issue #11982
29 */
30 #include <curl/curl.h>
31
32 #include <assert.h>
33 #include <stdio.h>
34 #include <string.h>
35 #include <stdlib.h>
36
37 #ifndef _MSC_VER
38 /* somewhat Unix-specific */
39 #include <unistd.h> /* getopt() */
40 #endif
41
42 #ifndef _MSC_VER
43 #define HANDLECOUNT 2
44
log_line_start(FILE * log,const char * idsbuf,curl_infotype type)45 static void log_line_start(FILE *log, const char *idsbuf, curl_infotype type)
46 {
47 /*
48 * This is the trace look that is similar to what libcurl makes on its
49 * own.
50 */
51 static const char * const s_infotype[] = {
52 "* ", "< ", "> ", "{ ", "} ", "{ ", "} "
53 };
54 if(idsbuf && *idsbuf)
55 fprintf(log, "%s%s", idsbuf, s_infotype[type]);
56 else
57 fputs(s_infotype[type], log);
58 }
59
60 #define TRC_IDS_FORMAT_IDS_1 "[%" CURL_FORMAT_CURL_OFF_T "-x] "
61 #define TRC_IDS_FORMAT_IDS_2 "[%" CURL_FORMAT_CURL_OFF_T "-%" \
62 CURL_FORMAT_CURL_OFF_T "] "
63 /*
64 ** callback for CURLOPT_DEBUGFUNCTION
65 */
debug_cb(CURL * handle,curl_infotype type,char * data,size_t size,void * userdata)66 static int debug_cb(CURL *handle, curl_infotype type,
67 char *data, size_t size,
68 void *userdata)
69 {
70 FILE *output = stderr;
71 static int newl = 0;
72 static int traced_data = 0;
73 char idsbuf[60];
74 curl_off_t xfer_id, conn_id;
75
76 (void)handle; /* not used */
77 (void)userdata;
78
79 if(!curl_easy_getinfo(handle, CURLINFO_XFER_ID, &xfer_id) && xfer_id >= 0) {
80 if(!curl_easy_getinfo(handle, CURLINFO_CONN_ID, &conn_id) &&
81 conn_id >= 0) {
82 curl_msnprintf(idsbuf, sizeof(idsbuf), TRC_IDS_FORMAT_IDS_2, xfer_id,
83 conn_id);
84 }
85 else {
86 curl_msnprintf(idsbuf, sizeof(idsbuf), TRC_IDS_FORMAT_IDS_1, xfer_id);
87 }
88 }
89 else
90 idsbuf[0] = 0;
91
92 switch(type) {
93 case CURLINFO_HEADER_OUT:
94 if(size > 0) {
95 size_t st = 0;
96 size_t i;
97 for(i = 0; i < size - 1; i++) {
98 if(data[i] == '\n') { /* LF */
99 if(!newl) {
100 log_line_start(output, idsbuf, type);
101 }
102 (void)fwrite(data + st, i - st + 1, 1, output);
103 st = i + 1;
104 newl = 0;
105 }
106 }
107 if(!newl)
108 log_line_start(output, idsbuf, type);
109 (void)fwrite(data + st, i - st + 1, 1, output);
110 }
111 newl = (size && (data[size - 1] != '\n')) ? 1 : 0;
112 traced_data = 0;
113 break;
114 case CURLINFO_TEXT:
115 case CURLINFO_HEADER_IN:
116 if(!newl)
117 log_line_start(output, idsbuf, type);
118 (void)fwrite(data, size, 1, output);
119 newl = (size && (data[size - 1] != '\n')) ? 1 : 0;
120 traced_data = 0;
121 break;
122 case CURLINFO_DATA_OUT:
123 case CURLINFO_DATA_IN:
124 case CURLINFO_SSL_DATA_IN:
125 case CURLINFO_SSL_DATA_OUT:
126 if(!traced_data) {
127 if(!newl)
128 log_line_start(output, idsbuf, type);
129 fprintf(output, "[%ld bytes data]\n", (long)size);
130 newl = 0;
131 traced_data = 1;
132 }
133 break;
134 default: /* nada */
135 newl = 0;
136 traced_data = 1;
137 break;
138 }
139
140 return 0;
141 }
142
err(void)143 static int err(void)
144 {
145 fprintf(stderr, "something unexpected went wrong - bailing out!\n");
146 exit(2);
147 }
148
usage(const char * msg)149 static void usage(const char *msg)
150 {
151 if(msg)
152 fprintf(stderr, "%s\n", msg);
153 fprintf(stderr,
154 "usage: [options] url\n"
155 " pause downloads with following options:\n"
156 " -V http_version (http/1.1, h2, h3) http version to use\n"
157 );
158 }
159
160 struct handle
161 {
162 int idx;
163 int paused;
164 int resumed;
165 int errored;
166 int fail_write;
167 CURL *h;
168 };
169
cb(char * data,size_t size,size_t nmemb,void * clientp)170 static size_t cb(char *data, size_t size, size_t nmemb, void *clientp)
171 {
172 size_t realsize = size * nmemb;
173 struct handle *handle = (struct handle *) clientp;
174 curl_off_t totalsize;
175
176 (void)data;
177 if(curl_easy_getinfo(handle->h, CURLINFO_CONTENT_LENGTH_DOWNLOAD_T,
178 &totalsize) == CURLE_OK)
179 fprintf(stderr, "INFO: [%d] write, Content-Length %"CURL_FORMAT_CURL_OFF_T
180 "\n", handle->idx, totalsize);
181
182 if(!handle->resumed) {
183 ++handle->paused;
184 fprintf(stderr, "INFO: [%d] write, PAUSING %d time on %lu bytes\n",
185 handle->idx, handle->paused, (long)realsize);
186 assert(handle->paused == 1);
187 return CURL_WRITEFUNC_PAUSE;
188 }
189 if(handle->fail_write) {
190 ++handle->errored;
191 fprintf(stderr, "INFO: [%d] FAIL write of %lu bytes, %d time\n",
192 handle->idx, (long)realsize, handle->errored);
193 return CURL_WRITEFUNC_ERROR;
194 }
195 fprintf(stderr, "INFO: [%d] write, accepting %lu bytes\n",
196 handle->idx, (long)realsize);
197 return realsize;
198 }
199 #endif /* !_MSC_VER */
200
main(int argc,char * argv[])201 int main(int argc, char *argv[])
202 {
203 #ifndef _MSC_VER
204 struct handle handles[HANDLECOUNT];
205 CURLM *multi_handle;
206 int i, still_running = 1, msgs_left, numfds;
207 CURLMsg *msg;
208 int rounds = 0;
209 int rc = 0;
210 CURLU *cu;
211 struct curl_slist *resolve = NULL;
212 char resolve_buf[1024];
213 char *url, *host = NULL, *port = NULL;
214 int all_paused = 0;
215 int resume_round = -1;
216 int http_version = CURL_HTTP_VERSION_2_0;
217 int ch;
218
219 while((ch = getopt(argc, argv, "hV:")) != -1) {
220 switch(ch) {
221 case 'h':
222 usage(NULL);
223 return 2;
224 case 'V': {
225 if(!strcmp("http/1.1", optarg))
226 http_version = CURL_HTTP_VERSION_1_1;
227 else if(!strcmp("h2", optarg))
228 http_version = CURL_HTTP_VERSION_2_0;
229 else if(!strcmp("h3", optarg))
230 http_version = CURL_HTTP_VERSION_3ONLY;
231 else {
232 usage("invalid http version");
233 return 1;
234 }
235 break;
236 }
237 default:
238 usage("invalid option");
239 return 1;
240 }
241 }
242 argc -= optind;
243 argv += optind;
244
245 if(argc != 1) {
246 fprintf(stderr, "ERROR: need URL as argument\n");
247 return 2;
248 }
249 url = argv[0];
250
251 curl_global_init(CURL_GLOBAL_DEFAULT);
252 curl_global_trace("ids,time,http/2,http/3");
253
254 cu = curl_url();
255 if(!cu) {
256 fprintf(stderr, "out of memory\n");
257 exit(1);
258 }
259 if(curl_url_set(cu, CURLUPART_URL, url, 0)) {
260 fprintf(stderr, "not a URL: '%s'\n", url);
261 exit(1);
262 }
263 if(curl_url_get(cu, CURLUPART_HOST, &host, 0)) {
264 fprintf(stderr, "could not get host of '%s'\n", url);
265 exit(1);
266 }
267 if(curl_url_get(cu, CURLUPART_PORT, &port, 0)) {
268 fprintf(stderr, "could not get port of '%s'\n", url);
269 exit(1);
270 }
271 memset(&resolve, 0, sizeof(resolve));
272 curl_msnprintf(resolve_buf, sizeof(resolve_buf)-1, "%s:%s:127.0.0.1",
273 host, port);
274 resolve = curl_slist_append(resolve, resolve_buf);
275
276 for(i = 0; i < HANDLECOUNT; i++) {
277 handles[i].idx = i;
278 handles[i].paused = 0;
279 handles[i].resumed = 0;
280 handles[i].errored = 0;
281 handles[i].fail_write = 1;
282 handles[i].h = curl_easy_init();
283 if(!handles[i].h ||
284 curl_easy_setopt(handles[i].h, CURLOPT_WRITEFUNCTION, cb) != CURLE_OK ||
285 curl_easy_setopt(handles[i].h, CURLOPT_WRITEDATA, &handles[i])
286 != CURLE_OK ||
287 curl_easy_setopt(handles[i].h, CURLOPT_FOLLOWLOCATION, 1L) != CURLE_OK ||
288 curl_easy_setopt(handles[i].h, CURLOPT_VERBOSE, 1L) != CURLE_OK ||
289 curl_easy_setopt(handles[i].h, CURLOPT_DEBUGFUNCTION, debug_cb)
290 != CURLE_OK ||
291 curl_easy_setopt(handles[i].h, CURLOPT_SSL_VERIFYPEER, 0L) != CURLE_OK ||
292 curl_easy_setopt(handles[i].h, CURLOPT_RESOLVE, resolve) != CURLE_OK ||
293 curl_easy_setopt(handles[i].h, CURLOPT_PIPEWAIT, 1L) ||
294 curl_easy_setopt(handles[i].h, CURLOPT_URL, url) != CURLE_OK) {
295 err();
296 }
297 curl_easy_setopt(handles[i].h, CURLOPT_HTTP_VERSION, (long)http_version);
298 }
299
300 multi_handle = curl_multi_init();
301 if(!multi_handle)
302 err();
303
304 for(i = 0; i < HANDLECOUNT; i++) {
305 if(curl_multi_add_handle(multi_handle, handles[i].h) != CURLM_OK)
306 err();
307 }
308
309 for(rounds = 0;; rounds++) {
310 fprintf(stderr, "INFO: multi_perform round %d\n", rounds);
311 if(curl_multi_perform(multi_handle, &still_running) != CURLM_OK)
312 err();
313
314 if(!still_running) {
315 int as_expected = 1;
316 fprintf(stderr, "INFO: no more handles running\n");
317 for(i = 0; i < HANDLECOUNT; i++) {
318 if(!handles[i].paused) {
319 fprintf(stderr, "ERROR: [%d] NOT PAUSED\n", i);
320 as_expected = 0;
321 }
322 else if(handles[i].paused != 1) {
323 fprintf(stderr, "ERROR: [%d] PAUSED %d times!\n",
324 i, handles[i].paused);
325 as_expected = 0;
326 }
327 else if(!handles[i].resumed) {
328 fprintf(stderr, "ERROR: [%d] NOT resumed!\n", i);
329 as_expected = 0;
330 }
331 else if(handles[i].errored != 1) {
332 fprintf(stderr, "ERROR: [%d] NOT errored once, %d instead!\n",
333 i, handles[i].errored);
334 as_expected = 0;
335 }
336 }
337 if(!as_expected) {
338 fprintf(stderr, "ERROR: handles not in expected state "
339 "after %d rounds\n", rounds);
340 rc = 1;
341 }
342 break;
343 }
344
345 if(curl_multi_poll(multi_handle, NULL, 0, 100, &numfds) != CURLM_OK)
346 err();
347
348 /* !checksrc! disable EQUALSNULL 1 */
349 while((msg = curl_multi_info_read(multi_handle, &msgs_left)) != NULL) {
350 if(msg->msg == CURLMSG_DONE) {
351 for(i = 0; i < HANDLECOUNT; i++) {
352 if(msg->easy_handle == handles[i].h) {
353 if(handles[i].paused != 1 || !handles[i].resumed) {
354 fprintf(stderr, "ERROR: [%d] done, pauses=%d, resumed=%d, "
355 "result %d - wtf?\n", i, handles[i].paused,
356 handles[i].resumed, msg->data.result);
357 rc = 1;
358 goto out;
359 }
360 }
361 }
362 }
363 }
364
365 /* Successfully paused? */
366 if(!all_paused) {
367 for(i = 0; i < HANDLECOUNT; i++) {
368 if(!handles[i].paused) {
369 break;
370 }
371 }
372 all_paused = (i == HANDLECOUNT);
373 if(all_paused) {
374 fprintf(stderr, "INFO: all transfers paused\n");
375 /* give transfer some rounds to mess things up */
376 resume_round = rounds + 2;
377 }
378 }
379 if(resume_round > 0 && rounds == resume_round) {
380 /* time to resume */
381 for(i = 0; i < HANDLECOUNT; i++) {
382 fprintf(stderr, "INFO: [%d] resumed\n", i);
383 handles[i].resumed = 1;
384 curl_easy_pause(handles[i].h, CURLPAUSE_CONT);
385 }
386 }
387 }
388
389 out:
390 for(i = 0; i < HANDLECOUNT; i++) {
391 curl_multi_remove_handle(multi_handle, handles[i].h);
392 curl_easy_cleanup(handles[i].h);
393 }
394
395
396 curl_slist_free_all(resolve);
397 curl_free(host);
398 curl_free(port);
399 curl_url_cleanup(cu);
400 curl_multi_cleanup(multi_handle);
401 curl_global_cleanup();
402
403 return rc;
404 #else
405 (void)argc;
406 (void)argv;
407 fprintf(stderr, "Not supported with this compiler.\n");
408 return 1;
409 #endif /* !_MSC_VER */
410 }
411
