Wird eine URL angefordert wird ein Worker-Thread mit curl-multi gestartet. Ist curl fertig wird der Thread wieder beendet.
Eigentlich total sinnlos, aber das habe ich erst bemerkt als es fast fertig war.
Daher noch eine Warnung:
Die Benutzung fuehrt zu unendlichem SNAFU
Zeilennummern

    1 #include <stdio.h>
    2 #include <pthread.h>
    3 #include <unistd.h>
    4 #include <curl/curl.h>
    5 
    6 static pthread_t __worker = 0;
    7 static CURL *__curl_hnd;
    8 static pthread_mutex_t __worker_mutex; // lock this when exiting while(handl
    9                                                                        es)
   10 
   11 
   12 static __attribute__ ((constructor))  void __cos_mutex()
   13 {
   14   pthread_mutex_init(&__worker_mutex, NULL);
   15   printf ("Created mutex\n");
   16 }
   17 
   18 static __attribute__ ((destructor)) void __dcos_mutex()
   19 {
   20   pthread_mutex_destroy(&__worker_mutex);
   21   printf ("Destroyed mutex\n");
   22 }
   23 
   24 static void *__fetcher_worker(void *p)
   25 {
   26   int msgs_in_queue, handles = 1;
   27   char *curlinfo_private;
   28   void (*feed_function)(void*, void*);
   29   CURLMsg *cmsg;
   30 
   31   printf("Started worker thread\n");
   32 
   33 
   34   while (1)
   35     {
   36       while ((cmsg = curl_multi_info_read(__curl_hnd, &msgs_in_queue)) !=
   37              NULL)
   38         if (cmsg->msg == CURLMSG_DONE)
   39           {
   40             curl_easy_getinfo(cmsg->easy_handle, CURLINFO_PRIVATE,
   41                               &curlinfo_private);
   42             feed_function = (void*)curlinfo_private;
   43             feed_function(NULL, NULL);
   44             curl_easy_cleanup(cmsg->easy_handle);
   45           }
   46 
   47       pthread_mutex_lock(&__worker_mutex);
   48       if (handles == 0)
   49         {
   50           curl_multi_cleanup(__curl_hnd);
   51           __worker = 0;
   52           __curl_hnd = NULL;
   53           pthread_mutex_unlock(&__worker_mutex);
   54           break;
   55         }
   56       pthread_mutex_unlock(&__worker_mutex);
   57 
   58       curl_multi_perform(__curl_hnd, &handles);
   59     }
   60 
   61   printf("Stopped worker thread\n");
   62 
   63   return NULL;
   64 }
   65 
   66 static void __fetcher_worker_start()
   67 {
   68   __worker = 1;
   69 
   70   __curl_hnd = curl_multi_init();
   71 
   72   pthread_create(&__worker, NULL, __fetcher_worker, NULL);
   73 
   74   //pthread_join(__worker, NULL);
   75   pthread_detach(__worker);
   76 }
   77 
   78 void fetcher_add_url(char *url, void *function, void *userdata)
   79 {
   80   CURL *hnd;
   81 
   82   hnd = curl_easy_init();
   83 
   84   curl_easy_setopt(hnd, CURLOPT_INFILESIZE_LARGE, (curl_off_t)-1);
   85   curl_easy_setopt(hnd, CURLOPT_URL, url);
   86   curl_easy_setopt(hnd, CURLOPT_NOPROGRESS, 1);
   87   curl_easy_setopt(hnd, CURLOPT_FAILONERROR, 0);
   88   curl_easy_setopt(hnd, CURLOPT_USERAGENT, "");
   89   curl_easy_setopt(hnd, CURLOPT_RESUME_FROM_LARGE, (curl_off_t)0);
   90   curl_easy_setopt(hnd, CURLOPT_MAXREDIRS, 50);
   91   curl_easy_setopt(hnd, CURLOPT_SSLVERSION, 0);
   92   curl_easy_setopt(hnd, CURLOPT_TIMECONDITION, 0);
   93   curl_easy_setopt(hnd, CURLOPT_TIMEVALUE, 0);
   94   curl_easy_setopt(hnd, CURLOPT_CUSTOMREQUEST, NULL);
   95   curl_easy_setopt(hnd, CURLOPT_CONNECTTIMEOUT, 0);
   96   curl_easy_setopt(hnd, CURLOPT_HTTPAUTH, 1);
   97   curl_easy_setopt(hnd, CURLOPT_ENCODING, NULL);
   98   curl_easy_setopt(hnd, CURLOPT_IPRESOLVE, 0);
   99   curl_easy_setopt(hnd, CURLOPT_IGNORE_CONTENT_LENGTH, 0);
  100   curl_easy_setopt(hnd, CURLOPT_POSTREDIR, 0);
  101   curl_easy_setopt(hnd, CURLOPT_WRITEFUNCTION, function);
  102   curl_easy_setopt(hnd, CURLOPT_PRIVATE, function);
  103   curl_easy_setopt(hnd, CURLOPT_WRITEDATA, userdata);
  104 
  105   pthread_mutex_lock(&__worker_mutex);
  106   if (__curl_hnd == NULL)
  107     __fetcher_worker_start();
  108   curl_multi_add_handle(__curl_hnd, hnd);
  109   pthread_mutex_unlock(&__worker_mutex);
  110 
  111 }
  112 
  113 size_t show(char *txt, size_t size, size_t nmemb, char *userdata)
  114 {
  115   int i;
  116 
  117   if (txt != NULL)
  118     {
  119       printf("\n--------------> userdata: %s\n", userdata);
  120       for (i = 0; i < nmemb*size; i++)
  121         printf("%c", txt[i]);
  122     }
  123   else
  124     printf("\n--------------------------------------------------------\n");
  125 
  126   fflush(stdout);
  127 
  128   return nmemb*size;
  129 
  130 }
  131 
  132 int main()
  133 {
  134   fetcher_add_url("http://www.google.de", show, "google");
  135   fetcher_add_url("http://www.heise.de", show, "heise");
  136   sleep(3);
  137   fetcher_add_url("http://www.google.de/news", show, "google-news");
  138 
  139   sleep(7);
  140   return 0;
  141 }