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 * multi socket interface together with libev
26 * </DESC>
27 */
28 /* Example application source code using the multi socket interface to
29 * download many files at once.
30 *
31 * This example features the same basic functionality as hiperfifo.c does,
32 * but this uses libev instead of libevent.
33 *
34 * Written by Jeff Pohlmeyer, converted to use libev by Markus Koetter
35
36 Requires libev and a (POSIX?) system that has mkfifo().
37
38 This is an adaptation of libcurl's "hipev.c" and libevent's "event-test.c"
39 sample programs.
40
41 When running, the program creates the named pipe "hiper.fifo"
42
43 Whenever there is input into the fifo, the program reads the input as a list
44 of URL's and creates some new easy handles to fetch each URL via the
45 curl_multi "hiper" API.
46
47
48 Thus, you can try a single URL:
49 % echo http://www.yahoo.com > hiper.fifo
50
51 Or a whole bunch of them:
52 % cat my-url-list > hiper.fifo
53
54 The fifo buffer is handled almost instantly, so you can even add more URL's
55 while the previous requests are still being downloaded.
56
57 Note:
58 For the sake of simplicity, URL length is limited to 1023 char's !
59
60 This is purely a demo app, all retrieved data is simply discarded by the write
61 callback.
62
63 */
64
65 #include <stdio.h>
66 #include <string.h>
67 #include <stdlib.h>
68 #include <sys/time.h>
69 #include <time.h>
70 #include <unistd.h>
71 #include <sys/poll.h>
72 #include <curl/curl.h>
73 #include <ev.h>
74 #include <fcntl.h>
75 #include <sys/stat.h>
76 #include <errno.h>
77
78 #define MSG_OUT stdout /* Send info to stdout, change to stderr if you want */
79
80
81 /* Global information, common to all connections */
82 typedef struct _GlobalInfo
83 {
84 struct ev_loop *loop;
85 struct ev_io fifo_event;
86 struct ev_timer timer_event;
87 CURLM *multi;
88 int still_running;
89 FILE *input;
90 } GlobalInfo;
91
92
93 /* Information associated with a specific easy handle */
94 typedef struct _ConnInfo
95 {
96 CURL *easy;
97 char *url;
98 GlobalInfo *global;
99 char error[CURL_ERROR_SIZE];
100 } ConnInfo;
101
102
103 /* Information associated with a specific socket */
104 typedef struct _SockInfo
105 {
106 curl_socket_t sockfd;
107 CURL *easy;
108 int action;
109 long timeout;
110 struct ev_io ev;
111 int evset;
112 GlobalInfo *global;
113 } SockInfo;
114
115 static void timer_cb(EV_P_ struct ev_timer *w, int revents);
116
117 /* Update the event timer after curl_multi library calls */
multi_timer_cb(CURLM * multi,long timeout_ms,GlobalInfo * g)118 static int multi_timer_cb(CURLM *multi, long timeout_ms, GlobalInfo *g)
119 {
120 (void)multi;
121 printf("%s %li\n", __PRETTY_FUNCTION__, timeout_ms);
122 ev_timer_stop(g->loop, &g->timer_event);
123 if(timeout_ms >= 0) {
124 /* -1 means delete, other values are timeout times in milliseconds */
125 double t = timeout_ms / 1000;
126 ev_timer_init(&g->timer_event, timer_cb, t, 0.);
127 ev_timer_start(g->loop, &g->timer_event);
128 }
129 return 0;
130 }
131
132 /* Die if we get a bad CURLMcode somewhere */
mcode_or_die(const char * where,CURLMcode code)133 static void mcode_or_die(const char *where, CURLMcode code)
134 {
135 if(CURLM_OK != code) {
136 const char *s;
137 switch(code) {
138 case CURLM_BAD_HANDLE:
139 s = "CURLM_BAD_HANDLE";
140 break;
141 case CURLM_BAD_EASY_HANDLE:
142 s = "CURLM_BAD_EASY_HANDLE";
143 break;
144 case CURLM_OUT_OF_MEMORY:
145 s = "CURLM_OUT_OF_MEMORY";
146 break;
147 case CURLM_INTERNAL_ERROR:
148 s = "CURLM_INTERNAL_ERROR";
149 break;
150 case CURLM_UNKNOWN_OPTION:
151 s = "CURLM_UNKNOWN_OPTION";
152 break;
153 case CURLM_LAST:
154 s = "CURLM_LAST";
155 break;
156 default:
157 s = "CURLM_unknown";
158 break;
159 case CURLM_BAD_SOCKET:
160 s = "CURLM_BAD_SOCKET";
161 fprintf(MSG_OUT, "ERROR: %s returns %s\n", where, s);
162 /* ignore this error */
163 return;
164 }
165 fprintf(MSG_OUT, "ERROR: %s returns %s\n", where, s);
166 exit(code);
167 }
168 }
169
170
171
172 /* Check for completed transfers, and remove their easy handles */
check_multi_info(GlobalInfo * g)173 static void check_multi_info(GlobalInfo *g)
174 {
175 char *eff_url;
176 CURLMsg *msg;
177 int msgs_left;
178 ConnInfo *conn;
179 CURL *easy;
180 CURLcode res;
181
182 fprintf(MSG_OUT, "REMAINING: %d\n", g->still_running);
183 while((msg = curl_multi_info_read(g->multi, &msgs_left))) {
184 if(msg->msg == CURLMSG_DONE) {
185 easy = msg->easy_handle;
186 res = msg->data.result;
187 curl_easy_getinfo(easy, CURLINFO_PRIVATE, &conn);
188 curl_easy_getinfo(easy, CURLINFO_EFFECTIVE_URL, &eff_url);
189 fprintf(MSG_OUT, "DONE: %s => (%d) %s\n", eff_url, res, conn->error);
190 curl_multi_remove_handle(g->multi, easy);
191 free(conn->url);
192 curl_easy_cleanup(easy);
193 free(conn);
194 }
195 }
196 }
197
198
199
200 /* Called by libevent when we get action on a multi socket */
event_cb(EV_P_ struct ev_io * w,int revents)201 static void event_cb(EV_P_ struct ev_io *w, int revents)
202 {
203 GlobalInfo *g;
204 CURLMcode rc;
205 int action;
206
207 printf("%s w %p revents %i\n", __PRETTY_FUNCTION__, (void *)w, revents);
208 g = (GlobalInfo*) w->data;
209
210 action = ((revents & EV_READ) ? CURL_POLL_IN : 0) |
211 ((revents & EV_WRITE) ? CURL_POLL_OUT : 0);
212 rc = curl_multi_socket_action(g->multi, w->fd, action, &g->still_running);
213 mcode_or_die("event_cb: curl_multi_socket_action", rc);
214 check_multi_info(g);
215 if(g->still_running <= 0) {
216 fprintf(MSG_OUT, "last transfer done, kill timeout\n");
217 ev_timer_stop(g->loop, &g->timer_event);
218 }
219 }
220
221 /* Called by libevent when our timeout expires */
timer_cb(EV_P_ struct ev_timer * w,int revents)222 static void timer_cb(EV_P_ struct ev_timer *w, int revents)
223 {
224 GlobalInfo *g;
225 CURLMcode rc;
226
227 printf("%s w %p revents %i\n", __PRETTY_FUNCTION__, (void *)w, revents);
228
229 g = (GlobalInfo *)w->data;
230
231 rc = curl_multi_socket_action(g->multi, CURL_SOCKET_TIMEOUT, 0,
232 &g->still_running);
233 mcode_or_die("timer_cb: curl_multi_socket_action", rc);
234 check_multi_info(g);
235 }
236
237 /* Clean up the SockInfo structure */
remsock(SockInfo * f,GlobalInfo * g)238 static void remsock(SockInfo *f, GlobalInfo *g)
239 {
240 printf("%s \n", __PRETTY_FUNCTION__);
241 if(f) {
242 if(f->evset)
243 ev_io_stop(g->loop, &f->ev);
244 free(f);
245 }
246 }
247
248
249
250 /* Assign information to a SockInfo structure */
setsock(SockInfo * f,curl_socket_t s,CURL * e,int act,GlobalInfo * g)251 static void setsock(SockInfo *f, curl_socket_t s, CURL *e, int act,
252 GlobalInfo *g)
253 {
254 int kind = ((act & CURL_POLL_IN) ? EV_READ : 0) |
255 ((act & CURL_POLL_OUT) ? EV_WRITE : 0);
256
257 printf("%s \n", __PRETTY_FUNCTION__);
258
259 f->sockfd = s;
260 f->action = act;
261 f->easy = e;
262 if(f->evset)
263 ev_io_stop(g->loop, &f->ev);
264 ev_io_init(&f->ev, event_cb, f->sockfd, kind);
265 f->ev.data = g;
266 f->evset = 1;
267 ev_io_start(g->loop, &f->ev);
268 }
269
270
271
272 /* Initialize a new SockInfo structure */
addsock(curl_socket_t s,CURL * easy,int action,GlobalInfo * g)273 static void addsock(curl_socket_t s, CURL *easy, int action, GlobalInfo *g)
274 {
275 SockInfo *fdp = calloc(1, sizeof(SockInfo));
276
277 fdp->global = g;
278 setsock(fdp, s, easy, action, g);
279 curl_multi_assign(g->multi, s, fdp);
280 }
281
282 /* CURLMOPT_SOCKETFUNCTION */
sock_cb(CURL * e,curl_socket_t s,int what,void * cbp,void * sockp)283 static int sock_cb(CURL *e, curl_socket_t s, int what, void *cbp, void *sockp)
284 {
285 GlobalInfo *g = (GlobalInfo*) cbp;
286 SockInfo *fdp = (SockInfo*) sockp;
287 const char *whatstr[]={ "none", "IN", "OUT", "INOUT", "REMOVE"};
288
289 printf("%s e %p s %i what %i cbp %p sockp %p\n",
290 __PRETTY_FUNCTION__, e, s, what, cbp, sockp);
291
292 fprintf(MSG_OUT,
293 "socket callback: s=%d e=%p what=%s ", s, e, whatstr[what]);
294 if(what == CURL_POLL_REMOVE) {
295 fprintf(MSG_OUT, "\n");
296 remsock(fdp, g);
297 }
298 else {
299 if(!fdp) {
300 fprintf(MSG_OUT, "Adding data: %s\n", whatstr[what]);
301 addsock(s, e, what, g);
302 }
303 else {
304 fprintf(MSG_OUT,
305 "Changing action from %s to %s\n",
306 whatstr[fdp->action], whatstr[what]);
307 setsock(fdp, s, e, what, g);
308 }
309 }
310 return 0;
311 }
312
313
314 /* CURLOPT_WRITEFUNCTION */
write_cb(void * ptr,size_t size,size_t nmemb,void * data)315 static size_t write_cb(void *ptr, size_t size, size_t nmemb, void *data)
316 {
317 size_t realsize = size * nmemb;
318 ConnInfo *conn = (ConnInfo*) data;
319 (void)ptr;
320 (void)conn;
321 return realsize;
322 }
323
324 /* CURLOPT_XFERINFOFUNCTION */
xferinfo_cb(void * p,curl_off_t dltotal,curl_off_t dlnow,curl_off_t ult,curl_off_t uln)325 static int xferinfo_cb(void *p, curl_off_t dltotal, curl_off_t dlnow,
326 curl_off_t ult, curl_off_t uln)
327 {
328 ConnInfo *conn = (ConnInfo *)p;
329 (void)ult;
330 (void)uln;
331
332 fprintf(MSG_OUT, "Progress: %s (%" CURL_FORMAT_CURL_OFF_T
333 "/%" CURL_FORMAT_CURL_OFF_T ")\n", conn->url, dlnow, dltotal);
334 return 0;
335 }
336
337
338 /* Create a new easy handle, and add it to the global curl_multi */
new_conn(const char * url,GlobalInfo * g)339 static void new_conn(const char *url, GlobalInfo *g)
340 {
341 ConnInfo *conn;
342 CURLMcode rc;
343
344 conn = calloc(1, sizeof(ConnInfo));
345 conn->error[0]='\0';
346
347 conn->easy = curl_easy_init();
348 if(!conn->easy) {
349 fprintf(MSG_OUT, "curl_easy_init() failed, exiting!\n");
350 exit(2);
351 }
352 conn->global = g;
353 conn->url = strdup(url);
354 curl_easy_setopt(conn->easy, CURLOPT_URL, conn->url);
355 curl_easy_setopt(conn->easy, CURLOPT_WRITEFUNCTION, write_cb);
356 curl_easy_setopt(conn->easy, CURLOPT_WRITEDATA, conn);
357 curl_easy_setopt(conn->easy, CURLOPT_VERBOSE, 1L);
358 curl_easy_setopt(conn->easy, CURLOPT_ERRORBUFFER, conn->error);
359 curl_easy_setopt(conn->easy, CURLOPT_PRIVATE, conn);
360 curl_easy_setopt(conn->easy, CURLOPT_NOPROGRESS, 0L);
361 curl_easy_setopt(conn->easy, CURLOPT_XFERINFOFUNCTION, xferinfo_cb);
362 curl_easy_setopt(conn->easy, CURLOPT_PROGRESSDATA, conn);
363 curl_easy_setopt(conn->easy, CURLOPT_LOW_SPEED_TIME, 3L);
364 curl_easy_setopt(conn->easy, CURLOPT_LOW_SPEED_LIMIT, 10L);
365
366 fprintf(MSG_OUT,
367 "Adding easy %p to multi %p (%s)\n", conn->easy, g->multi, url);
368 rc = curl_multi_add_handle(g->multi, conn->easy);
369 mcode_or_die("new_conn: curl_multi_add_handle", rc);
370
371 /* note that add_handle() sets a timeout to trigger soon so that the
372 necessary socket_action() gets called */
373 }
374
375 /* This gets called whenever data is received from the fifo */
fifo_cb(EV_P_ struct ev_io * w,int revents)376 static void fifo_cb(EV_P_ struct ev_io *w, int revents)
377 {
378 char s[1024];
379 long int rv = 0;
380 int n = 0;
381 GlobalInfo *g = (GlobalInfo *)w->data;
382
383 (void)revents;
384
385 do {
386 s[0]='\0';
387 rv = fscanf(g->input, "%1023s%n", s, &n);
388 s[n]='\0';
389 if(n && s[0]) {
390 new_conn(s, g); /* if we read a URL, go get it! */
391 }
392 else
393 break;
394 } while(rv != EOF);
395 }
396
397 /* Create a named pipe and tell libevent to monitor it */
init_fifo(GlobalInfo * g)398 static int init_fifo(GlobalInfo *g)
399 {
400 struct stat st;
401 static const char *fifo = "hiper.fifo";
402 curl_socket_t sockfd;
403
404 fprintf(MSG_OUT, "Creating named pipe \"%s\"\n", fifo);
405 if(lstat (fifo, &st) == 0) {
406 if((st.st_mode & S_IFMT) == S_IFREG) {
407 errno = EEXIST;
408 perror("lstat");
409 exit(1);
410 }
411 }
412 unlink(fifo);
413 if(mkfifo (fifo, 0600) == -1) {
414 perror("mkfifo");
415 exit(1);
416 }
417 sockfd = open(fifo, O_RDWR | O_NONBLOCK, 0);
418 if(sockfd == -1) {
419 perror("open");
420 exit(1);
421 }
422 g->input = fdopen(sockfd, "r");
423
424 fprintf(MSG_OUT, "Now, pipe some URL's into > %s\n", fifo);
425 ev_io_init(&g->fifo_event, fifo_cb, sockfd, EV_READ);
426 ev_io_start(g->loop, &g->fifo_event);
427 return (0);
428 }
429
main(int argc,char ** argv)430 int main(int argc, char **argv)
431 {
432 GlobalInfo g;
433 (void)argc;
434 (void)argv;
435
436 memset(&g, 0, sizeof(GlobalInfo));
437 g.loop = ev_default_loop(0);
438
439 init_fifo(&g);
440 g.multi = curl_multi_init();
441
442 ev_timer_init(&g.timer_event, timer_cb, 0., 0.);
443 g.timer_event.data = &g;
444 g.fifo_event.data = &g;
445 curl_multi_setopt(g.multi, CURLMOPT_SOCKETFUNCTION, sock_cb);
446 curl_multi_setopt(g.multi, CURLMOPT_SOCKETDATA, &g);
447 curl_multi_setopt(g.multi, CURLMOPT_TIMERFUNCTION, multi_timer_cb);
448 curl_multi_setopt(g.multi, CURLMOPT_TIMERDATA, &g);
449
450 /* we do not call any curl_multi_socket*() function yet as we have no handles
451 added! */
452
453 ev_loop(g.loop, 0);
454 curl_multi_cleanup(g.multi);
455 return 0;
456 }
457
