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 server push
26 * </DESC>
27 */
28
29 /* curl stuff */
30 #include <curl/curl.h>
31 #include <curl/mprintf.h>
32
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <string.h>
36
37 /* somewhat unix-specific */
38 #include <sys/time.h>
39 #include <unistd.h>
40
41 #ifndef CURLPIPE_MULTIPLEX
42 #error "too old libcurl, cannot do HTTP/2 server push!"
43 #endif
44
45 static int verbose = 1;
46
47 static
my_trace(CURL * handle,curl_infotype type,char * data,size_t size,void * userp)48 int my_trace(CURL *handle, curl_infotype type,
49 char *data, size_t size,
50 void *userp)
51 {
52 const char *text;
53 (void)handle; /* prevent compiler warning */
54 (void)userp;
55
56 switch(type) {
57 case CURLINFO_TEXT:
58 fprintf(stderr, "== Info: %s", data);
59 return 0;
60 case CURLINFO_HEADER_OUT:
61 text = "=> Send header";
62 break;
63 case CURLINFO_DATA_OUT:
64 if(verbose <= 1)
65 return 0;
66 text = "=> Send data";
67 break;
68 case CURLINFO_HEADER_IN:
69 text = "<= Recv header";
70 break;
71 case CURLINFO_DATA_IN:
72 if(verbose <= 1)
73 return 0;
74 text = "<= Recv data";
75 break;
76 default: /* in case a new one is introduced to shock us */
77 return 0;
78 }
79
80 fprintf(stderr, "%s, %lu bytes (0x%lx)\n",
81 text, (unsigned long)size, (unsigned long)size);
82 return 0;
83 }
84
85 struct transfer {
86 int idx;
87 CURL *easy;
88 char filename[128];
89 FILE *out;
90 curl_off_t recv_size;
91 curl_off_t pause_at;
92 int started;
93 int paused;
94 int resumed;
95 int done;
96 };
97
98 static size_t transfer_count = 1;
99 static struct transfer *transfers;
100
get_transfer_for_easy(CURL * easy)101 static struct transfer *get_transfer_for_easy(CURL *easy)
102 {
103 size_t i;
104 for(i = 0; i < transfer_count; ++i) {
105 if(easy == transfers[i].easy)
106 return &transfers[i];
107 }
108 return NULL;
109 }
110
my_write_cb(char * buf,size_t nitems,size_t buflen,void * userdata)111 static size_t my_write_cb(char *buf, size_t nitems, size_t buflen,
112 void *userdata)
113 {
114 struct transfer *t = userdata;
115 size_t nwritten;
116
117 if(!t->resumed &&
118 t->recv_size < t->pause_at &&
119 ((t->recv_size + (curl_off_t)(nitems * buflen)) >= t->pause_at)) {
120 fprintf(stderr, "[t-%d] PAUSE\n", t->idx);
121 t->paused = 1;
122 return CURL_WRITEFUNC_PAUSE;
123 }
124
125 if(!t->out) {
126 curl_msnprintf(t->filename, sizeof(t->filename)-1, "download_%u.data",
127 t->idx);
128 t->out = fopen(t->filename, "wb");
129 if(!t->out)
130 return 0;
131 }
132
133 nwritten = fwrite(buf, nitems, buflen, t->out);
134 if(nwritten < buflen) {
135 fprintf(stderr, "[t-%d] write failure\n", t->idx);
136 return 0;
137 }
138 t->recv_size += (curl_off_t)nwritten;
139 return (size_t)nwritten;
140 }
141
setup(CURL * hnd,const char * url,struct transfer * t)142 static int setup(CURL *hnd, const char *url, struct transfer *t)
143 {
144 curl_easy_setopt(hnd, CURLOPT_URL, url);
145 curl_easy_setopt(hnd, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_2_0);
146 curl_easy_setopt(hnd, CURLOPT_SSL_VERIFYPEER, 0L);
147 curl_easy_setopt(hnd, CURLOPT_SSL_VERIFYHOST, 0L);
148
149 curl_easy_setopt(hnd, CURLOPT_WRITEFUNCTION, my_write_cb);
150 curl_easy_setopt(hnd, CURLOPT_WRITEDATA, t);
151
152 /* please be verbose */
153 if(verbose) {
154 curl_easy_setopt(hnd, CURLOPT_VERBOSE, 1L);
155 curl_easy_setopt(hnd, CURLOPT_DEBUGFUNCTION, my_trace);
156 }
157
158 #if (CURLPIPE_MULTIPLEX > 0)
159 /* wait for pipe connection to confirm */
160 curl_easy_setopt(hnd, CURLOPT_PIPEWAIT, 1L);
161 #endif
162 return 0; /* all is good */
163 }
164
usage(const char * msg)165 static void usage(const char *msg)
166 {
167 if(msg)
168 fprintf(stderr, "%s\n", msg);
169 fprintf(stderr,
170 "usage: [options] url\n"
171 " download a url with following options:\n"
172 " -m number max parallel downloads\n"
173 " -n number total downloads\n"
174 " -P number pause transfer after `number` response bytes\n"
175 );
176 }
177
178 /*
179 * Download a file over HTTP/2, take care of server push.
180 */
main(int argc,char * argv[])181 int main(int argc, char *argv[])
182 {
183 CURLM *multi_handle;
184 struct CURLMsg *m;
185 const char *url;
186 size_t i, n, max_parallel = 1;
187 size_t active_transfers;
188 size_t pause_offset = 0;
189 int abort_paused = 0;
190 struct transfer *t;
191 int ch;
192
193 while((ch = getopt(argc, argv, "ahm:n:P:")) != -1) {
194 switch(ch) {
195 case 'h':
196 usage(NULL);
197 return 2;
198 case 'a':
199 abort_paused = 1;
200 break;
201 case 'm':
202 max_parallel = (size_t)strtol(optarg, NULL, 10);
203 break;
204 case 'n':
205 transfer_count = (size_t)strtol(optarg, NULL, 10);
206 break;
207 case 'P':
208 pause_offset = (size_t)strtol(optarg, NULL, 10);
209 break;
210 default:
211 usage("invalid option");
212 return 1;
213 }
214 }
215 argc -= optind;
216 argv += optind;
217
218 if(argc != 1) {
219 usage("not enough arguments");
220 return 2;
221 }
222 url = argv[0];
223
224 transfers = calloc(transfer_count, sizeof(*transfers));
225 if(!transfers) {
226 fprintf(stderr, "error allocating transfer structs\n");
227 return 1;
228 }
229
230 multi_handle = curl_multi_init();
231 curl_multi_setopt(multi_handle, CURLMOPT_PIPELINING, CURLPIPE_MULTIPLEX);
232
233 active_transfers = 0;
234 for(i = 0; i < transfer_count; ++i) {
235 t = &transfers[i];
236 t->idx = (int)i;
237 t->pause_at = (curl_off_t)(pause_offset * i);
238 }
239
240 n = (max_parallel < transfer_count)? max_parallel : transfer_count;
241 for(i = 0; i < n; ++i) {
242 t = &transfers[i];
243 t->easy = curl_easy_init();
244 if(!t->easy || setup(t->easy, url, t)) {
245 fprintf(stderr, "[t-%d] FAILED setup\n", (int)i);
246 return 1;
247 }
248 curl_multi_add_handle(multi_handle, t->easy);
249 t->started = 1;
250 ++active_transfers;
251 fprintf(stderr, "[t-%d] STARTED\n", t->idx);
252 }
253
254 do {
255 int still_running; /* keep number of running handles */
256 CURLMcode mc = curl_multi_perform(multi_handle, &still_running);
257
258 if(still_running) {
259 /* wait for activity, timeout or "nothing" */
260 mc = curl_multi_poll(multi_handle, NULL, 0, 1000, NULL);
261 fprintf(stderr, "curl_multi_poll() -> %d\n", mc);
262 }
263
264 if(mc)
265 break;
266
267 do {
268 int msgq = 0;
269 m = curl_multi_info_read(multi_handle, &msgq);
270 if(m && (m->msg == CURLMSG_DONE)) {
271 CURL *e = m->easy_handle;
272 active_transfers--;
273 curl_multi_remove_handle(multi_handle, e);
274 t = get_transfer_for_easy(e);
275 if(t) {
276 t->done = 1;
277 }
278 else
279 curl_easy_cleanup(e);
280 }
281 else {
282 /* nothing happening, maintenance */
283 if(abort_paused) {
284 /* abort paused transfers */
285 for(i = 0; i < transfer_count; ++i) {
286 t = &transfers[i];
287 if(!t->done && t->paused && t->easy) {
288 curl_multi_remove_handle(multi_handle, t->easy);
289 t->done = 1;
290 active_transfers--;
291 fprintf(stderr, "[t-%d] ABORTED\n", t->idx);
292 }
293 }
294 }
295 else {
296 /* resume one paused transfer */
297 for(i = 0; i < transfer_count; ++i) {
298 t = &transfers[i];
299 if(!t->done && t->paused) {
300 t->resumed = 1;
301 t->paused = 0;
302 curl_easy_pause(t->easy, CURLPAUSE_CONT);
303 fprintf(stderr, "[t-%d] RESUMED\n", t->idx);
304 break;
305 }
306 }
307 }
308
309 while(active_transfers < max_parallel) {
310 for(i = 0; i < transfer_count; ++i) {
311 t = &transfers[i];
312 if(!t->started) {
313 t->easy = curl_easy_init();
314 if(!t->easy || setup(t->easy, url, t)) {
315 fprintf(stderr, "[t-%d] FAILEED setup\n", (int)i);
316 return 1;
317 }
318 curl_multi_add_handle(multi_handle, t->easy);
319 t->started = 1;
320 ++active_transfers;
321 fprintf(stderr, "[t-%d] STARTED\n", t->idx);
322 break;
323 }
324 }
325 /* all started */
326 if(i == transfer_count)
327 break;
328 }
329 }
330 } while(m);
331
332 } while(active_transfers); /* as long as we have transfers going */
333
334 for(i = 0; i < transfer_count; ++i) {
335 t = &transfers[i];
336 if(t->out) {
337 fclose(t->out);
338 t->out = NULL;
339 }
340 if(t->easy) {
341 curl_easy_cleanup(t->easy);
342 t->easy = NULL;
343 }
344 }
345 free(transfers);
346
347 curl_multi_cleanup(multi_handle);
348
349 return 0;
350 }
351