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    1: /***************************************************************************
    2:  *                                  _   _ ____  _
    3:  *  Project                     ___| | | |  _ \| |
    4:  *                             / __| | | | |_) | |
    5:  *                            | (__| |_| |  _ <| |___
    6:  *                             \___|\___/|_| \_\_____|
    7:  *
    8:  * Copyright (C) 1998 - 2019, 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.haxx.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:  ***************************************************************************/
   22: /* <DESC>
   23:  * Multiplexed HTTP/2 downloads over a single connection
   24:  * </DESC>
   25:  */
   26: #include <stdio.h>
   27: #include <stdlib.h>
   28: #include <string.h>
   29: 
   30: /* somewhat unix-specific */
   31: #include <sys/time.h>
   32: #include <unistd.h>
   33: 
   34: /* curl stuff */
   35: #include <curl/curl.h>
   36: 
   37: #ifndef CURLPIPE_MULTIPLEX
   38: /* This little trick will just make sure that we don't enable pipelining for
   39:    libcurls old enough to not have this symbol. It is _not_ defined to zero in
   40:    a recent libcurl header. */
   41: #define CURLPIPE_MULTIPLEX 0
   42: #endif
   43: 
   44: struct transfer {
   45:   CURL *easy;
   46:   unsigned int num;
   47:   FILE *out;
   48: };
   49: 
   50: #define NUM_HANDLES 1000
   51: 
   52: static
   53: void dump(const char *text, int num, unsigned char *ptr, size_t size,
   54:           char nohex)
   55: {
   56:   size_t i;
   57:   size_t c;
   58: 
   59:   unsigned int width = 0x10;
   60: 
   61:   if(nohex)
   62:     /* without the hex output, we can fit more on screen */
   63:     width = 0x40;
   64: 
   65:   fprintf(stderr, "%d %s, %lu bytes (0x%lx)\n",
   66:           num, text, (unsigned long)size, (unsigned long)size);
   67: 
   68:   for(i = 0; i<size; i += width) {
   69: 
   70:     fprintf(stderr, "%4.4lx: ", (unsigned long)i);
   71: 
   72:     if(!nohex) {
   73:       /* hex not disabled, show it */
   74:       for(c = 0; c < width; c++)
   75:         if(i + c < size)
   76:           fprintf(stderr, "%02x ", ptr[i + c]);
   77:         else
   78:           fputs("   ", stderr);
   79:     }
   80: 
   81:     for(c = 0; (c < width) && (i + c < size); c++) {
   82:       /* check for 0D0A; if found, skip past and start a new line of output */
   83:       if(nohex && (i + c + 1 < size) && ptr[i + c] == 0x0D &&
   84:          ptr[i + c + 1] == 0x0A) {
   85:         i += (c + 2 - width);
   86:         break;
   87:       }
   88:       fprintf(stderr, "%c",
   89:               (ptr[i + c] >= 0x20) && (ptr[i + c]<0x80)?ptr[i + c]:'.');
   90:       /* check again for 0D0A, to avoid an extra \n if it's at width */
   91:       if(nohex && (i + c + 2 < size) && ptr[i + c + 1] == 0x0D &&
   92:          ptr[i + c + 2] == 0x0A) {
   93:         i += (c + 3 - width);
   94:         break;
   95:       }
   96:     }
   97:     fputc('\n', stderr); /* newline */
   98:   }
   99: }
  100: 
  101: static
  102: int my_trace(CURL *handle, curl_infotype type,
  103:              char *data, size_t size,
  104:              void *userp)
  105: {
  106:   const char *text;
  107:   struct transfer *t = (struct transfer *)userp;
  108:   unsigned int num = t->num;
  109:   (void)handle; /* prevent compiler warning */
  110: 
  111:   switch(type) {
  112:   case CURLINFO_TEXT:
  113:     fprintf(stderr, "== %u Info: %s", num, data);
  114:     /* FALLTHROUGH */
  115:   default: /* in case a new one is introduced to shock us */
  116:     return 0;
  117: 
  118:   case CURLINFO_HEADER_OUT:
  119:     text = "=> Send header";
  120:     break;
  121:   case CURLINFO_DATA_OUT:
  122:     text = "=> Send data";
  123:     break;
  124:   case CURLINFO_SSL_DATA_OUT:
  125:     text = "=> Send SSL data";
  126:     break;
  127:   case CURLINFO_HEADER_IN:
  128:     text = "<= Recv header";
  129:     break;
  130:   case CURLINFO_DATA_IN:
  131:     text = "<= Recv data";
  132:     break;
  133:   case CURLINFO_SSL_DATA_IN:
  134:     text = "<= Recv SSL data";
  135:     break;
  136:   }
  137: 
  138:   dump(text, num, (unsigned char *)data, size, 1);
  139:   return 0;
  140: }
  141: 
  142: static void setup(struct transfer *t, int num)
  143: {
  144:   char filename[128];
  145:   CURL *hnd;
  146: 
  147:   hnd = t->easy = curl_easy_init();
  148: 
  149:   snprintf(filename, 128, "dl-%d", num);
  150: 
  151:   t->out = fopen(filename, "wb");
  152: 
  153:   /* write to this file */
  154:   curl_easy_setopt(hnd, CURLOPT_WRITEDATA, t->out);
  155: 
  156:   /* set the same URL */
  157:   curl_easy_setopt(hnd, CURLOPT_URL, "https://localhost:8443/index.html");
  158: 
  159:   /* please be verbose */
  160:   curl_easy_setopt(hnd, CURLOPT_VERBOSE, 1L);
  161:   curl_easy_setopt(hnd, CURLOPT_DEBUGFUNCTION, my_trace);
  162:   curl_easy_setopt(hnd, CURLOPT_DEBUGDATA, t);
  163: 
  164:   /* HTTP/2 please */
  165:   curl_easy_setopt(hnd, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_2_0);
  166: 
  167:   /* we use a self-signed test server, skip verification during debugging */
  168:   curl_easy_setopt(hnd, CURLOPT_SSL_VERIFYPEER, 0L);
  169:   curl_easy_setopt(hnd, CURLOPT_SSL_VERIFYHOST, 0L);
  170: 
  171: #if (CURLPIPE_MULTIPLEX > 0)
  172:   /* wait for pipe connection to confirm */
  173:   curl_easy_setopt(hnd, CURLOPT_PIPEWAIT, 1L);
  174: #endif
  175: }
  176: 
  177: /*
  178:  * Download many transfers over HTTP/2, using the same connection!
  179:  */
  180: int main(int argc, char **argv)
  181: {
  182:   struct transfer trans[NUM_HANDLES];
  183:   CURLM *multi_handle;
  184:   int i;
  185:   int still_running = 0; /* keep number of running handles */
  186:   int num_transfers;
  187:   if(argc > 1) {
  188:     /* if given a number, do that many transfers */
  189:     num_transfers = atoi(argv[1]);
  190:     if((num_transfers < 1) || (num_transfers > NUM_HANDLES))
  191:       num_transfers = 3; /* a suitable low default */
  192:   }
  193:   else
  194:     num_transfers = 3; /* suitable default */
  195: 
  196:   /* init a multi stack */
  197:   multi_handle = curl_multi_init();
  198: 
  199:   for(i = 0; i < num_transfers; i++) {
  200:     setup(&trans[i], i);
  201: 
  202:     /* add the individual transfer */
  203:     curl_multi_add_handle(multi_handle, trans[i].easy);
  204:   }
  205: 
  206:   curl_multi_setopt(multi_handle, CURLMOPT_PIPELINING, CURLPIPE_MULTIPLEX);
  207: 
  208:   /* we start some action by calling perform right away */
  209:   curl_multi_perform(multi_handle, &still_running);
  210: 
  211:   while(still_running) {
  212:     struct timeval timeout;
  213:     int rc; /* select() return code */
  214:     CURLMcode mc; /* curl_multi_fdset() return code */
  215: 
  216:     fd_set fdread;
  217:     fd_set fdwrite;
  218:     fd_set fdexcep;
  219:     int maxfd = -1;
  220: 
  221:     long curl_timeo = -1;
  222: 
  223:     FD_ZERO(&fdread);
  224:     FD_ZERO(&fdwrite);
  225:     FD_ZERO(&fdexcep);
  226: 
  227:     /* set a suitable timeout to play around with */
  228:     timeout.tv_sec = 1;
  229:     timeout.tv_usec = 0;
  230: 
  231:     curl_multi_timeout(multi_handle, &curl_timeo);
  232:     if(curl_timeo >= 0) {
  233:       timeout.tv_sec = curl_timeo / 1000;
  234:       if(timeout.tv_sec > 1)
  235:         timeout.tv_sec = 1;
  236:       else
  237:         timeout.tv_usec = (curl_timeo % 1000) * 1000;
  238:     }
  239: 
  240:     /* get file descriptors from the transfers */
  241:     mc = curl_multi_fdset(multi_handle, &fdread, &fdwrite, &fdexcep, &maxfd);
  242: 
  243:     if(mc != CURLM_OK) {
  244:       fprintf(stderr, "curl_multi_fdset() failed, code %d.\n", mc);
  245:       break;
  246:     }
  247: 
  248:     /* On success the value of maxfd is guaranteed to be >= -1. We call
  249:        select(maxfd + 1, ...); specially in case of (maxfd == -1) there are
  250:        no fds ready yet so we call select(0, ...) --or Sleep() on Windows--
  251:        to sleep 100ms, which is the minimum suggested value in the
  252:        curl_multi_fdset() doc. */
  253: 
  254:     if(maxfd == -1) {
  255: #ifdef _WIN32
  256:       Sleep(100);
  257:       rc = 0;
  258: #else
  259:       /* Portable sleep for platforms other than Windows. */
  260:       struct timeval wait = { 0, 100 * 1000 }; /* 100ms */
  261:       rc = select(0, NULL, NULL, NULL, &wait);
  262: #endif
  263:     }
  264:     else {
  265:       /* Note that on some platforms 'timeout' may be modified by select().
  266:          If you need access to the original value save a copy beforehand. */
  267:       rc = select(maxfd + 1, &fdread, &fdwrite, &fdexcep, &timeout);
  268:     }
  269: 
  270:     switch(rc) {
  271:     case -1:
  272:       /* select error */
  273:       break;
  274:     case 0:
  275:     default:
  276:       /* timeout or readable/writable sockets */
  277:       curl_multi_perform(multi_handle, &still_running);
  278:       break;
  279:     }
  280:   }
  281: 
  282:   for(i = 0; i < num_transfers; i++) {
  283:     curl_multi_remove_handle(multi_handle, trans[i].easy);
  284:     curl_easy_cleanup(trans[i].easy);
  285:   }
  286: 
  287:   curl_multi_cleanup(multi_handle);
  288: 
  289:   return 0;
  290: }