text: /***************************************************************************
   *                                  _   _ ____  _
   *  Project                     ___| | | |  _ \| |
   *                             / __| | | | |_) | |
   *                            | (__| |_| |  _ <| |___
   *                             \___|\___/|_| \_\_____|
   *
   * Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.
   *
   * This software is licensed as described in the file COPYING, which
   * you should have received as part of this distribution. The terms
   * are also available at https://curl.haxx.se/docs/copyright.html.
   *
   * You may opt to use, copy, modify, merge, publish, distribute and/or sell
   * copies of the Software, and permit persons to whom the Software is
   * furnished to do so, under the terms of the COPYING file.
   *
   * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
   * KIND, either express or implied.
   *
   ***************************************************************************/
  /* <DESC>
   * A multi threaded application that uses a progress bar to show
   * status.  It uses Gtk+ to make a smooth pulse.
   * </DESC>
   */
  /*
   * Written by Jud Bishop after studying the other examples provided with
   * libcurl.
   *
   * To compile (on a single line):
   * gcc -ggdb `pkg-config --cflags  --libs gtk+-2.0` -lcurl -lssl -lcrypto
   *   -lgthread-2.0 -dl  smooth-gtk-thread.c -o smooth-gtk-thread
   */
  
  #include <stdio.h>
  #include <gtk/gtk.h>
  #include <glib.h>
  #include <unistd.h>
  #include <pthread.h>
  
  #include <curl/curl.h>
  
  #define NUMT 4
  
  pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
  int j = 0;
  gint num_urls = 9; /* Just make sure this is less than urls[]*/
  const char * const urls[]= {
    "90022",
    "90023",
    "90024",
    "90025",
    "90026",
    "90027",
    "90028",
    "90029",
    "90030"
  };
  
  size_t write_file(void *ptr, size_t size, size_t nmemb, FILE *stream)
  {
    /* printf("write_file\n"); */
    return fwrite(ptr, size, nmemb, stream);
  }
  
  /* https://weather.com/weather/today/l/46214?cc=*&dayf=5&unit=i */
  void *pull_one_url(void *NaN)
  {
    CURL *curl;
    gchar *http;
    FILE *outfile;
  
    /* Stop threads from entering unless j is incremented */
    pthread_mutex_lock(&lock);
    while(j < num_urls) {
      printf("j = %d\n", j);
  
      http =
        g_strdup_printf("xoap.weather.com/weather/local/%s?cc=*&dayf=5&unit=i\n",
                        urls[j]);
  
      printf("http %s", http);
  
      curl = curl_easy_init();
      if(curl) {
  
        outfile = fopen(urls[j], "wb");
  
        /* Set the URL and transfer type */
        curl_easy_setopt(curl, CURLOPT_URL, http);
  
        /* Write to the file */
        curl_easy_setopt(curl, CURLOPT_WRITEDATA, outfile);
        curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_file);
  
        j++;  /* critical line */
        pthread_mutex_unlock(&lock);
  
        curl_easy_perform(curl);
  
        fclose(outfile);
        printf("fclose\n");
  
        curl_easy_cleanup(curl);
      }
      g_free(http);
  
      /* Adds more latency, testing the mutex.*/
      sleep(1);
  
    } /* end while */
    return NULL;
  }
  
  
  gboolean pulse_bar(gpointer data)
  {
    gdk_threads_enter();
    gtk_progress_bar_pulse(GTK_PROGRESS_BAR (data));
    gdk_threads_leave();
  
    /* Return true so the function will be called again;
     * returning false removes this timeout function.
     */
    return TRUE;
  }
  
  void *create_thread(void *progress_bar)
  {
    pthread_t tid[NUMT];
    int i;
  
    /* Make sure I don't create more threads than urls. */
    for(i = 0; i < NUMT && i < num_urls ; i++) {
      int error = pthread_create(&tid[i],
                                 NULL, /* default attributes please */
                                 pull_one_url,
                                 NULL);
      if(0 != error)
        fprintf(stderr, "Couldn't run thread number %d, errno %d\n", i, error);
      else
        fprintf(stderr, "Thread %d, gets %s\n", i, urls[i]);
    }
  
    /* Wait for all threads to terminate. */
    for(i = 0; i < NUMT && i < num_urls; i++) {
      pthread_join(tid[i], NULL);
      fprintf(stderr, "Thread %d terminated\n", i);
    }
  
    /* This stops the pulsing if you have it turned on in the progress bar
       section */
    g_source_remove(GPOINTER_TO_INT(g_object_get_data(G_OBJECT(progress_bar),
                                                      "pulse_id")));
  
    /* This destroys the progress bar */
    gtk_widget_destroy(progress_bar);
  
    /* [Un]Comment this out to kill the program rather than pushing close. */
    /* gtk_main_quit(); */
  
  
    return NULL;
  
  }
  
  static gboolean cb_delete(GtkWidget *window, gpointer data)
  {
    gtk_main_quit();
    return FALSE;
  }
  
  int main(int argc, char **argv)
  {
    GtkWidget *top_window, *outside_frame, *inside_frame, *progress_bar;
  
    /* Must initialize libcurl before any threads are started */
    curl_global_init(CURL_GLOBAL_ALL);
  
    /* Init thread */
    g_thread_init(NULL);
    gdk_threads_init();
    gdk_threads_enter();
  
    gtk_init(&argc, &argv);
  
    /* Base window */
    top_window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
  
    /* Frame */
    outside_frame = gtk_frame_new(NULL);
    gtk_frame_set_shadow_type(GTK_FRAME(outside_frame), GTK_SHADOW_OUT);
    gtk_container_add(GTK_CONTAINER(top_window), outside_frame);
  
    /* Frame */
    inside_frame = gtk_frame_new(NULL);
    gtk_frame_set_shadow_type(GTK_FRAME(inside_frame), GTK_SHADOW_IN);
    gtk_container_set_border_width(GTK_CONTAINER(inside_frame), 5);
    gtk_container_add(GTK_CONTAINER(outside_frame), inside_frame);
  
    /* Progress bar */
    progress_bar = gtk_progress_bar_new();
    gtk_progress_bar_pulse(GTK_PROGRESS_BAR (progress_bar));
    /* Make uniform pulsing */
    gint pulse_ref = g_timeout_add(300, pulse_bar, progress_bar);
    g_object_set_data(G_OBJECT(progress_bar), "pulse_id",
                      GINT_TO_POINTER(pulse_ref));
    gtk_container_add(GTK_CONTAINER(inside_frame), progress_bar);
  
    gtk_widget_show_all(top_window);
    printf("gtk_widget_show_all\n");
  
    g_signal_connect(G_OBJECT (top_window), "delete-event",
                     G_CALLBACK(cb_delete), NULL);
  
    if(!g_thread_create(&create_thread, progress_bar, FALSE, NULL) != 0)
      g_warning("can't create the thread");
  
    gtk_main();
    gdk_threads_leave();
    printf("gdk_threads_leave\n");
  
    return 0;
  }
  