Return to multi-debugcallback.c CVS log

Up to [ELWIX - Embedded LightWeight unIX -] / embedaddon / curl / docs / examples

curl

    1: /***************************************************************************
    2:  *                                  _   _ ____  _
    3:  *  Project                     ___| | | |  _ \| |
    4:  *                             / __| | | | |_) | |
    5:  *                            | (__| |_| |  _ <| |___
    6:  *                             \___|\___/|_| \_\_____|
    7:  *
    8:  * Copyright (C) 1998 - 2018, 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:  * multi interface and debug callback
   24:  * </DESC>
   25:  */
   26: 
   27: #include <stdio.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: typedef char bool;
   38: #define TRUE 1
   39: 
   40: static
   41: void dump(const char *text,
   42:           FILE *stream, unsigned char *ptr, size_t size,
   43:           bool nohex)
   44: {
   45:   size_t i;
   46:   size_t c;
   47: 
   48:   unsigned int width = 0x10;
   49: 
   50:   if(nohex)
   51:     /* without the hex output, we can fit more on screen */
   52:     width = 0x40;
   53: 
   54:   fprintf(stream, "%s, %10.10lu bytes (0x%8.8lx)\n",
   55:           text, (unsigned long)size, (unsigned long)size);
   56: 
   57:   for(i = 0; i<size; i += width) {
   58: 
   59:     fprintf(stream, "%4.4lx: ", (unsigned long)i);
   60: 
   61:     if(!nohex) {
   62:       /* hex not disabled, show it */
   63:       for(c = 0; c < width; c++)
   64:         if(i + c < size)
   65:           fprintf(stream, "%02x ", ptr[i + c]);
   66:         else
   67:           fputs("   ", stream);
   68:     }
   69: 
   70:     for(c = 0; (c < width) && (i + c < size); c++) {
   71:       /* check for 0D0A; if found, skip past and start a new line of output */
   72:       if(nohex && (i + c + 1 < size) && ptr[i + c] == 0x0D &&
   73:          ptr[i + c + 1] == 0x0A) {
   74:         i += (c + 2 - width);
   75:         break;
   76:       }
   77:       fprintf(stream, "%c",
   78:               (ptr[i + c] >= 0x20) && (ptr[i + c]<0x80)?ptr[i + c]:'.');
   79:       /* check again for 0D0A, to avoid an extra \n if it's at width */
   80:       if(nohex && (i + c + 2 < size) && ptr[i + c + 1] == 0x0D &&
   81:          ptr[i + c + 2] == 0x0A) {
   82:         i += (c + 3 - width);
   83:         break;
   84:       }
   85:     }
   86:     fputc('\n', stream); /* newline */
   87:   }
   88:   fflush(stream);
   89: }
   90: 
   91: static
   92: int my_trace(CURL *handle, curl_infotype type,
   93:              unsigned char *data, size_t size,
   94:              void *userp)
   95: {
   96:   const char *text;
   97: 
   98:   (void)userp;
   99:   (void)handle; /* prevent compiler warning */
  100: 
  101:   switch(type) {
  102:   case CURLINFO_TEXT:
  103:     fprintf(stderr, "== Info: %s", data);
  104:     /* FALLTHROUGH */
  105:   default: /* in case a new one is introduced to shock us */
  106:     return 0;
  107: 
  108:   case CURLINFO_HEADER_OUT:
  109:     text = "=> Send header";
  110:     break;
  111:   case CURLINFO_DATA_OUT:
  112:     text = "=> Send data";
  113:     break;
  114:   case CURLINFO_HEADER_IN:
  115:     text = "<= Recv header";
  116:     break;
  117:   case CURLINFO_DATA_IN:
  118:     text = "<= Recv data";
  119:     break;
  120:   }
  121: 
  122:   dump(text, stderr, data, size, TRUE);
  123:   return 0;
  124: }
  125: 
  126: /*
  127:  * Simply download a HTTP file.
  128:  */
  129: int main(void)
  130: {
  131:   CURL *http_handle;
  132:   CURLM *multi_handle;
  133: 
  134:   int still_running = 0; /* keep number of running handles */
  135: 
  136:   http_handle = curl_easy_init();
  137: 
  138:   /* set the options (I left out a few, you'll get the point anyway) */
  139:   curl_easy_setopt(http_handle, CURLOPT_URL, "https://www.example.com/");
  140: 
  141:   curl_easy_setopt(http_handle, CURLOPT_DEBUGFUNCTION, my_trace);
  142:   curl_easy_setopt(http_handle, CURLOPT_VERBOSE, 1L);
  143: 
  144:   /* init a multi stack */
  145:   multi_handle = curl_multi_init();
  146: 
  147:   /* add the individual transfers */
  148:   curl_multi_add_handle(multi_handle, http_handle);
  149: 
  150:   /* we start some action by calling perform right away */
  151:   curl_multi_perform(multi_handle, &still_running);
  152: 
  153:   while(still_running) {
  154:     struct timeval timeout;
  155:     int rc; /* select() return code */
  156:     CURLMcode mc; /* curl_multi_fdset() return code */
  157: 
  158:     fd_set fdread;
  159:     fd_set fdwrite;
  160:     fd_set fdexcep;
  161:     int maxfd = -1;
  162: 
  163:     long curl_timeo = -1;
  164: 
  165:     FD_ZERO(&fdread);
  166:     FD_ZERO(&fdwrite);
  167:     FD_ZERO(&fdexcep);
  168: 
  169:     /* set a suitable timeout to play around with */
  170:     timeout.tv_sec = 1;
  171:     timeout.tv_usec = 0;
  172: 
  173:     curl_multi_timeout(multi_handle, &curl_timeo);
  174:     if(curl_timeo >= 0) {
  175:       timeout.tv_sec = curl_timeo / 1000;
  176:       if(timeout.tv_sec > 1)
  177:         timeout.tv_sec = 1;
  178:       else
  179:         timeout.tv_usec = (curl_timeo % 1000) * 1000;
  180:     }
  181: 
  182:     /* get file descriptors from the transfers */
  183:     mc = curl_multi_fdset(multi_handle, &fdread, &fdwrite, &fdexcep, &maxfd);
  184: 
  185:     if(mc != CURLM_OK) {
  186:       fprintf(stderr, "curl_multi_fdset() failed, code %d.\n", mc);
  187:       break;
  188:     }
  189: 
  190:     /* On success the value of maxfd is guaranteed to be >= -1. We call
  191:        select(maxfd + 1, ...); specially in case of (maxfd == -1) there are
  192:        no fds ready yet so we call select(0, ...) --or Sleep() on Windows--
  193:        to sleep 100ms, which is the minimum suggested value in the
  194:        curl_multi_fdset() doc. */
  195: 
  196:     if(maxfd == -1) {
  197: #ifdef _WIN32
  198:       Sleep(100);
  199:       rc = 0;
  200: #else
  201:       /* Portable sleep for platforms other than Windows. */
  202:       struct timeval wait = { 0, 100 * 1000 }; /* 100ms */
  203:       rc = select(0, NULL, NULL, NULL, &wait);
  204: #endif
  205:     }
  206:     else {
  207:       /* Note that on some platforms 'timeout' may be modified by select().
  208:          If you need access to the original value save a copy beforehand. */
  209:       rc = select(maxfd + 1, &fdread, &fdwrite, &fdexcep, &timeout);
  210:     }
  211: 
  212:     switch(rc) {
  213:     case -1:
  214:       /* select error */
  215:       still_running = 0;
  216:       printf("select() returns error, this is badness\n");
  217:       break;
  218:     case 0:
  219:     default:
  220:       /* timeout or readable/writable sockets */
  221:       curl_multi_perform(multi_handle, &still_running);
  222:       break;
  223:     }
  224:   }
  225: 
  226:   curl_multi_cleanup(multi_handle);
  227: 
  228:   curl_easy_cleanup(http_handle);
  229: 
  230:   return 0;
  231: }