trunk/src/gcvote.c

/*
 * This file is part of GPXView.
 *
 * GPXView is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * GPXView is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with GPXView.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <curl/curl.h>
#include <curl/types.h>
#include <curl/easy.h>

#include <libxml/parser.h>
#include <libxml/tree.h>

#include <glib/gstdio.h>

#include <fcntl.h>

#ifndef LIBXML_TREE_ENABLED
#error "Tree not enabled in libxml"
#endif

#include "gpxview.h"

#define ID_PATTERN  "guid="

static size_t mem_write(void *ptr, size_t size, size_t nmemb,
                        void *stream) {
  curl_mem_t *p = (curl_mem_t*)stream;

  p->ptr = g_realloc(p->ptr, p->len + size*nmemb + 1);
  if(p->ptr) {
    memcpy(p->ptr+p->len, ptr, size*nmemb);
    p->len += size*nmemb;
    p->ptr[p->len] = 0;
  }
  return nmemb;
}

/* return list of all votes in this file */
static gcvote_t *votes_parse(xmlDocPtr doc, xmlNode *a_node) {
  xmlNode *cur_node = NULL;

  gcvote_t *votes = NULL, **cur = &votes;

  for (cur_node = a_node->children; cur_node; cur_node = cur_node->next) {
    if (cur_node->type == XML_ELEMENT_NODE) {

      if(strcasecmp((char*)cur_node->name, "vote") == 0) {
        *cur = g_new0(gcvote_t, 1);
        (*cur)->quality = GCVOTE_NONE;

        /* unhandled attributes: */
        /* userName, voteAvg, voteUser, waypoint, vote1-5 */

        /* parse votes attributes */
        char *prop_str = (char*)xmlGetProp(cur_node, BAD_CAST "voteMedian");
        if(prop_str) { 
          (*cur)->quality = atoi(prop_str);
          xmlFree(prop_str);
        }

        prop_str = (char*)xmlGetProp(cur_node, BAD_CAST "voteCnt");
        if(prop_str) {
          (*cur)->votes = atoi(prop_str);
          xmlFree(prop_str);
        }

        prop_str = (char*)xmlGetProp(cur_node, BAD_CAST "cacheId");
        if(prop_str) {
          (*cur)->id = g_strdup(prop_str);
          xmlFree(prop_str);
        }

        cur = &(*cur)->next;
      } else if(strcasecmp((char*)cur_node->name, "errorstring") == 0) {
        /* ignore for now ... */
      } else 
        printf("found unhandled votes/%s\n", cur_node->name);
    }
  } 
  return votes;
}

/* parse root element */
static gcvote_t *parse_root(xmlDocPtr doc, xmlNode *a_node) {
  xmlNode *cur_node = NULL;
  gcvote_t *votes = NULL;

  for (cur_node = a_node; cur_node; cur_node = cur_node->next) {
    if (cur_node->type == XML_ELEMENT_NODE) {

      if(strcasecmp((char*)cur_node->name, "votes") == 0) {
        if(!votes)
          votes = votes_parse(doc, cur_node);
        else
          printf("gcvote: ignoring multiple votes lists\n");
      } else 
        printf("found unhandled %s\n", cur_node->name);
    }
  }
  return votes;
}

static gcvote_t *parse_doc(xmlDocPtr doc) {
  /* Get the root element node */
  xmlNode *root_element = xmlDocGetRootElement(doc);
  gcvote_t *votes = parse_root(doc, root_element);  

  /*free the document */
  xmlFreeDoc(doc);

  /*
   * Free the global variables that may
   * have been allocated by the parser.
   */
  xmlCleanupParser();

  return votes;
}

static void curl_set_proxy(CURL *curl, proxy_t *proxy) {
  if(proxy) {
    if(proxy->ignore_hosts)
      printf("WARNING: Proxy \"ignore_hosts\" unsupported!\n");

    printf("gcvote: using proxy %s:%d\n", proxy->host, proxy->port);

    curl_easy_setopt(curl, CURLOPT_PROXY, proxy->host);
    curl_easy_setopt(curl, CURLOPT_PROXYPORT, proxy->port);

    if(proxy->use_authentication) {
      printf("gcvote:   use auth for user %s\n", proxy->authentication_user);

      char *cred = g_strdup_printf("%s:%s",
                                   proxy->authentication_user,
                                   proxy->authentication_password);

      curl_easy_setopt(curl, CURLOPT_PROXYUSERPWD, cred);
      g_free(cred);
    }
  } else
    printf("gcvote: no proxy configured\n");
}

void gcvote_request_free(gcvote_request_t *request) {
  /* decrease refcount and only free structure if no references are left */
  request->refcount--;
  if(request->refcount) {
    printf("gcvote: still %d references, keeping request\n", 
           request->refcount);
    return;
  }

  printf("gcvote: no references left, freeing request\n");
  if(request->url)  g_free(request->url);

  if(request->mem.ptr)
    g_free(request->mem.ptr);

  g_free(request);
}

/* gcvote net result handler */
static gboolean gcvote_result_handler(gpointer data) {
  gcvote_request_t *request = (gcvote_request_t*)data;

  printf("gcvote: result handler\n");

  /* worker thread has already reduced its refcounter */
  if(request->refcount < 1) {
    printf("gcvote: main app isn't listening anymore\n");
    return FALSE;
  }

  if(request->res) {
    printf("gcvote: curl failed\n");
    request->cb(NULL, request->userdata);
    return FALSE;
  }

  /* parse the reply */
  /* nothing could be parsed, just give up */
  if(!request->mem.ptr || !request->mem.len) { 
    printf("gcvote: ignoring zero length reply\n");
    request->cb(NULL, request->userdata);
    return FALSE;
  }

  /* start XML parser */
  LIBXML_TEST_VERSION;

  /* parse the file and get the DOM */
  xmlDoc *doc = xmlReadMemory(request->mem.ptr, request->mem.len, 
                              NULL, NULL, 0);

  /* nothing could be parsed, just give up */
  if(!doc) { 
    request->cb(NULL, request->userdata);
    return FALSE;
  }

  vote_t *vote = NULL;
  gcvote_t *votes = parse_doc(doc);
  
  /* search for requested cache in reply and free chain */
  while(votes) {
    gcvote_t *next = votes->next;

    if(!vote && !strcmp(votes->id, request->id) && (votes->quality > 0)) {

      vote = g_new0(vote_t, 1);
      vote->quality = votes->quality;
      vote->votes = votes->votes;
    }

    if(votes->id) g_free(votes->id);
    g_free(votes);
    votes = next;
  }

  if(vote) {
    printf("gcvote: worker found vote %d/%d\n", vote->quality, vote->votes);
    request->cb(vote, request->userdata);
  } else
    printf("gcvote: no vote found\n");

  return FALSE;
}

static void gcvotes_free(gcvote_t *votes) {
  while(votes) {
    gcvote_t *next = votes->next;
    if(votes->id) g_free(votes->id);
    g_free(votes);
    votes = next;
  }
}

void gcvote_save(appdata_t *appdata, cache_t *cache, curl_mem_t *mem) {
  if(!mem->len || !mem->ptr) return;

  /* save data to disk */
  char *filename = g_strdup_printf("%s%s/gcvote.xml",
                                   appdata->image_path,
                                   cache->id);
  if(checkdir(filename) != 0) 
    printf("gcvote: unable to create file path\n");
  else {
    printf("gcvote: write %d bytes to %s\n", mem->len, filename);

    int handle = g_open(filename, O_WRONLY | O_CREAT, 0644);
    if(handle >= 0) {
      int len = write(handle, mem->ptr, mem->len);
      close(handle);
      
      /* if write failed, then remove the file */
      if(len != mem->len) 
        g_remove(filename);
    }
  }

  free(filename);
}

static void *worker_thread(void *ptr) {
  gcvote_request_t *request = (gcvote_request_t*)ptr;
  struct curl_httppost *formpost=NULL;
  struct curl_httppost *lastptr=NULL;
  
  printf("gcvote: worker thread running\n");

  request->mem.ptr = NULL;
  request->mem.len = 0;

  printf("gcvote: request to get votes for id %s\n", request->id);

  curl_formadd(&formpost, &lastptr,
               CURLFORM_COPYNAME, "version",
               CURLFORM_COPYCONTENTS, APP VERSION,
               CURLFORM_END);
  
  curl_formadd(&formpost, &lastptr,
               CURLFORM_COPYNAME, "cacheIds",
               CURLFORM_COPYCONTENTS, request->id,
               CURLFORM_END);
  
  /* try to init curl */
  CURL *curl = curl_easy_init();
  if(!curl) {
    curl_formfree(formpost);
    gcvote_request_free(request);

    /* callback anyway, so main loop can also clean up */
    g_idle_add(gcvote_result_handler, request); 
  
    return NULL;
  }
  
  curl_set_proxy(curl, request->proxy);
  
  /* play nice and report some user agent */
  curl_easy_setopt(curl, CURLOPT_USERAGENT, APP " " VERSION);
  
  /* download to memory */
  curl_easy_setopt(curl, CURLOPT_WRITEDATA, &request->mem);
  curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, mem_write);
  
  /* what URL that receives this POST */ 
  curl_easy_setopt(curl, CURLOPT_URL, 
                   "http://dosensuche.de/GCVote/getVotes.php");
  curl_easy_setopt(curl, CURLOPT_HTTPPOST, formpost);
  
  request->res = curl_easy_perform(curl);
  printf("gcvote: curl perform returned with %d\n", request->res);
  
  //  printf("received %d bytes\n", mem.len);
  //  printf("data: %s\n", mem.ptr);
  
  /* always cleanup */ 
  curl_easy_cleanup(curl);
  
  curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &request->response);
  
  /* then cleanup the formpost chain */ 
  curl_formfree(formpost);

  printf("gcvote: worker thread done\n");
  gcvote_request_free(request);

  /* cause gtk main loop to handle result */
  g_idle_add(gcvote_result_handler, request); 
  
  printf("gcvote: thread terminating\n");
  
  return NULL;
}

gcvote_request_t *gcvote_request(appdata_t *appdata, gcvote_cb cb, 
                               char *url, gpointer data) {
  if(!url) return NULL;
  
  /* ------ prepare request for worker thread --------- */
  gcvote_request_t *request = g_new0(gcvote_request_t, 1);
  request->url = g_strdup(url);
  request->id = strstr(request->url, ID_PATTERN);
  if(!request->id) {
    printf("gcvote: unable to find id\n");
    gcvote_request_free(request);
    return NULL;
  }
  
  request->proxy = appdata->proxy;
  request->id += strlen(ID_PATTERN);
  request->refcount = 2;   // master and worker hold a reference
  request->cb = cb;
  request->userdata = data;

  if(!g_thread_create(&worker_thread, request, FALSE, NULL) != 0) {
    g_warning("gcvote: failed to create the worker thread");

    /* free request and return error */
    request->refcount--;    /* decrease by one for dead worker thread */
    gcvote_request_free(request);
    return NULL;
  }

  return request;
}

vote_t *gcvote_restore(appdata_t *appdata, cache_t *cache) {
  /* load data from disk */
  char *filename = g_strdup_printf("%s%s/gcvote.xml",
                                   appdata->image_path,
                                   cache->id);

  printf("gcvote: trying to restore from %s\n", filename);

  /* no such file? */
  if(!g_file_test(filename, G_FILE_TEST_EXISTS)) {
    printf("gcvote: no such file\n");
    free(filename);
    return NULL;
  }

  LIBXML_TEST_VERSION;
  xmlDoc *doc = xmlReadFile(filename, NULL, 0);

  if(doc == NULL) {
    printf("gcvote: error, could not parse file %s\n", filename);
    free(filename);
    return NULL;
  }
 
  free(filename);

  /* in this case this will sure only return one result */
  gcvote_t *votes = parse_doc(doc);
  
  if(!votes) {
    printf("gcvote: error, no vote found\n");
    free(filename);
    return NULL;
  }

  vote_t *vote = g_new0(vote_t, 1);
  vote->quality = votes->quality;
  vote->votes = votes->votes;

  printf("gcvote: found vote %d/%d\n", vote->quality, vote->votes);

  gcvotes_free(votes);

  return vote;
}
1	/*
2	* This file is part of GPXView.
3	*
4	* GPXView is free software: you can redistribute it and/or modify
5	* it under the terms of the GNU General Public License as published by
6	* the Free Software Foundation, either version 3 of the License, or
7	* (at your option) any later version.
8	*
9	* GPXView is distributed in the hope that it will be useful,
10	* but WITHOUT ANY WARRANTY; without even the implied warranty of
11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12	* GNU General Public License for more details.
13	*
14	* You should have received a copy of the GNU General Public License
15	* along with GPXView. If not, see <http://www.gnu.org/licenses/>.
16	*/
17
18	#include <curl/curl.h>
19	#include <curl/types.h>
20	#include <curl/easy.h>
21
22	#include <libxml/parser.h>
23	#include <libxml/tree.h>
24
25	#include <glib/gstdio.h>
26
27	#include <fcntl.h>
28
29	#ifndef LIBXML_TREE_ENABLED
30	#error "Tree not enabled in libxml"
31	#endif
32
33	#include "gpxview.h"
34
35	#define ID_PATTERN "guid="
36
37	static size_t mem_write(void *ptr, size_t size, size_t nmemb,
38	void *stream) {
39	curl_mem_t p = (curl_mem_t)stream;
40
41	p->ptr = g_realloc(p->ptr, p->len + size*nmemb + 1);
42	if(p->ptr) {
43	memcpy(p->ptr+p->len, ptr, size*nmemb);
44	p->len += size*nmemb;
45	p->ptr[p->len] = 0;
46	}
47	return nmemb;
48	}
49
50	/* return list of all votes in this file */
51	static gcvote_t votes_parse(xmlDocPtr doc, xmlNode a_node) {
52	xmlNode *cur_node = NULL;
53
54	gcvote_t votes = NULL, *cur = &votes;
55
56	for (cur_node = a_node->children; cur_node; cur_node = cur_node->next) {
57	if (cur_node->type == XML_ELEMENT_NODE) {
58
59	if(strcasecmp((char*)cur_node->name, "vote") == 0) {
60	*cur = g_new0(gcvote_t, 1);
61	(*cur)->quality = GCVOTE_NONE;
62
63	/* unhandled attributes: */
64	/* userName, voteAvg, voteUser, waypoint, vote1-5 */
65
66	/* parse votes attributes */
67	char prop_str = (char)xmlGetProp(cur_node, BAD_CAST "voteMedian");
68	if(prop_str) {
69	(*cur)->quality = atoi(prop_str);
70	xmlFree(prop_str);
71	}
72
73	prop_str = (char*)xmlGetProp(cur_node, BAD_CAST "voteCnt");
74	if(prop_str) {
75	(*cur)->votes = atoi(prop_str);
76	xmlFree(prop_str);
77	}
78
79	prop_str = (char*)xmlGetProp(cur_node, BAD_CAST "cacheId");
80	if(prop_str) {
81	(*cur)->id = g_strdup(prop_str);
82	xmlFree(prop_str);
83	}
84
85	cur = &(*cur)->next;
86	} else if(strcasecmp((char*)cur_node->name, "errorstring") == 0) {
87	/* ignore for now ... */
88	} else
89	printf("found unhandled votes/%s\n", cur_node->name);
90	}
91	}
92	return votes;
93	}
94
95	/* parse root element */
96	static gcvote_t parse_root(xmlDocPtr doc, xmlNode a_node) {
97	xmlNode *cur_node = NULL;
98	gcvote_t *votes = NULL;
99
100	for (cur_node = a_node; cur_node; cur_node = cur_node->next) {
101	if (cur_node->type == XML_ELEMENT_NODE) {
102
103	if(strcasecmp((char*)cur_node->name, "votes") == 0) {
104	if(!votes)
105	votes = votes_parse(doc, cur_node);
106	else
107	printf("gcvote: ignoring multiple votes lists\n");
108	} else
109	printf("found unhandled %s\n", cur_node->name);
110	}
111	}
112	return votes;
113	}
114
115	static gcvote_t *parse_doc(xmlDocPtr doc) {
116	/* Get the root element node */
117	xmlNode *root_element = xmlDocGetRootElement(doc);
118	gcvote_t *votes = parse_root(doc, root_element);
119
120	/free the document /
121	xmlFreeDoc(doc);
122
123	/*
124	* Free the global variables that may
125	* have been allocated by the parser.
126	*/
127	xmlCleanupParser();
128
129	return votes;
130	}
131
132	static void curl_set_proxy(CURL curl, proxy_t proxy) {
133	if(proxy) {
134	if(proxy->ignore_hosts)
135	printf("WARNING: Proxy \"ignore_hosts\" unsupported!\n");
136
137	printf("gcvote: using proxy %s:%d\n", proxy->host, proxy->port);
138
139	curl_easy_setopt(curl, CURLOPT_PROXY, proxy->host);
140	curl_easy_setopt(curl, CURLOPT_PROXYPORT, proxy->port);
141
142	if(proxy->use_authentication) {
143	printf("gcvote: use auth for user %s\n", proxy->authentication_user);
144
145	char *cred = g_strdup_printf("%s:%s",
146	proxy->authentication_user,
147	proxy->authentication_password);
148
149	curl_easy_setopt(curl, CURLOPT_PROXYUSERPWD, cred);
150	g_free(cred);
151	}
152	} else
153	printf("gcvote: no proxy configured\n");
154	}
155
156	void gcvote_request_free(gcvote_request_t *request) {
157	/* decrease refcount and only free structure if no references are left */
158	request->refcount--;
159	if(request->refcount) {
160	printf("gcvote: still %d references, keeping request\n",
161	request->refcount);
162	return;
163	}
164
165	printf("gcvote: no references left, freeing request\n");
166	if(request->url) g_free(request->url);
167
168	if(request->mem.ptr)
169	g_free(request->mem.ptr);
170
171	g_free(request);
172	}
173
174	/* gcvote net result handler */
175	static gboolean gcvote_result_handler(gpointer data) {
176	gcvote_request_t request = (gcvote_request_t)data;
177
178	printf("gcvote: result handler\n");
179
180	/* worker thread has already reduced its refcounter */
181	if(request->refcount < 1) {
182	printf("gcvote: main app isn't listening anymore\n");
183	return FALSE;
184	}
185
186	if(request->res) {
187	printf("gcvote: curl failed\n");
188	request->cb(NULL, request->userdata);
189	return FALSE;
190	}
191
192	/* parse the reply */
193	/* nothing could be parsed, just give up */
194	if(!request->mem.ptr \|\| !request->mem.len) {
195	printf("gcvote: ignoring zero length reply\n");
196	request->cb(NULL, request->userdata);
197	return FALSE;
198	}
199
200	/* start XML parser */
201	LIBXML_TEST_VERSION;
202
203	/* parse the file and get the DOM */
204	xmlDoc *doc = xmlReadMemory(request->mem.ptr, request->mem.len,
205	NULL, NULL, 0);
206
207	/* nothing could be parsed, just give up */
208	if(!doc) {
209	request->cb(NULL, request->userdata);
210	return FALSE;
211	}
212
213	vote_t *vote = NULL;
214	gcvote_t *votes = parse_doc(doc);
215
216	/* search for requested cache in reply and free chain */
217	while(votes) {
218	gcvote_t *next = votes->next;
219
220	if(!vote && !strcmp(votes->id, request->id) && (votes->quality > 0)) {
221
222	vote = g_new0(vote_t, 1);
223	vote->quality = votes->quality;
224	vote->votes = votes->votes;
225	}
226
227	if(votes->id) g_free(votes->id);
228	g_free(votes);
229	votes = next;
230	}
231
232	if(vote) {
233	printf("gcvote: worker found vote %d/%d\n", vote->quality, vote->votes);
234	request->cb(vote, request->userdata);
235	} else
236	printf("gcvote: no vote found\n");
237
238	return FALSE;
239	}
240
241	static void gcvotes_free(gcvote_t *votes) {
242	while(votes) {
243	gcvote_t *next = votes->next;
244	if(votes->id) g_free(votes->id);
245	g_free(votes);
246	votes = next;
247	}
248	}
249
250	void gcvote_save(appdata_t appdata, cache_t cache, curl_mem_t *mem) {
251	if(!mem->len \|\| !mem->ptr) return;
252
253	/* save data to disk */
254	char *filename = g_strdup_printf("%s%s/gcvote.xml",
255	appdata->image_path,
256	cache->id);
257	if(checkdir(filename) != 0)
258	printf("gcvote: unable to create file path\n");
259	else {
260	printf("gcvote: write %d bytes to %s\n", mem->len, filename);
261
262	int handle = g_open(filename, O_WRONLY \| O_CREAT, 0644);
263	if(handle >= 0) {
264	int len = write(handle, mem->ptr, mem->len);
265	close(handle);
266
267	/* if write failed, then remove the file */
268	if(len != mem->len)
269	g_remove(filename);
270	}
271	}
272
273	free(filename);
274	}
275
276	static void worker_thread(void ptr) {
277	gcvote_request_t request = (gcvote_request_t)ptr;
278	struct curl_httppost *formpost=NULL;
279	struct curl_httppost *lastptr=NULL;
280
281	printf("gcvote: worker thread running\n");
282
283	request->mem.ptr = NULL;
284	request->mem.len = 0;
285
286	printf("gcvote: request to get votes for id %s\n", request->id);
287
288	curl_formadd(&formpost, &lastptr,
289	CURLFORM_COPYNAME, "version",
290	CURLFORM_COPYCONTENTS, APP VERSION,
291	CURLFORM_END);
292
293	curl_formadd(&formpost, &lastptr,
294	CURLFORM_COPYNAME, "cacheIds",
295	CURLFORM_COPYCONTENTS, request->id,
296	CURLFORM_END);
297
298	/* try to init curl */
299	CURL *curl = curl_easy_init();
300	if(!curl) {
301	curl_formfree(formpost);
302	gcvote_request_free(request);
303
304	/* callback anyway, so main loop can also clean up */
305	g_idle_add(gcvote_result_handler, request);
306
307	return NULL;
308	}
309
310	curl_set_proxy(curl, request->proxy);
311
312	/* play nice and report some user agent */
313	curl_easy_setopt(curl, CURLOPT_USERAGENT, APP " " VERSION);
314
315	/* download to memory */
316	curl_easy_setopt(curl, CURLOPT_WRITEDATA, &request->mem);
317	curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, mem_write);
318
319	/* what URL that receives this POST */
320	curl_easy_setopt(curl, CURLOPT_URL,
321	"http://dosensuche.de/GCVote/getVotes.php");
322	curl_easy_setopt(curl, CURLOPT_HTTPPOST, formpost);
323
324	request->res = curl_easy_perform(curl);
325	printf("gcvote: curl perform returned with %d\n", request->res);
326
327	// printf("received %d bytes\n", mem.len);
328	// printf("data: %s\n", mem.ptr);
329
330	/* always cleanup */
331	curl_easy_cleanup(curl);
332
333	curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &request->response);
334
335	/* then cleanup the formpost chain */
336	curl_formfree(formpost);
337
338	printf("gcvote: worker thread done\n");
339	gcvote_request_free(request);
340
341	/* cause gtk main loop to handle result */
342	g_idle_add(gcvote_result_handler, request);
343
344	printf("gcvote: thread terminating\n");
345
346	return NULL;
347	}
348
349	gcvote_request_t gcvote_request(appdata_t appdata, gcvote_cb cb,
350	char *url, gpointer data) {
351	if(!url) return NULL;
352
353	/* ------ prepare request for worker thread --------- */
354	gcvote_request_t *request = g_new0(gcvote_request_t, 1);
355	request->url = g_strdup(url);
356	request->id = strstr(request->url, ID_PATTERN);
357	if(!request->id) {
358	printf("gcvote: unable to find id\n");
359	gcvote_request_free(request);
360	return NULL;
361	}
362
363	request->proxy = appdata->proxy;
364	request->id += strlen(ID_PATTERN);
365	request->refcount = 2; // master and worker hold a reference
366	request->cb = cb;
367	request->userdata = data;
368
369	if(!g_thread_create(&worker_thread, request, FALSE, NULL) != 0) {
370	g_warning("gcvote: failed to create the worker thread");
371
372	/* free request and return error */
373	request->refcount--; /* decrease by one for dead worker thread */
374	gcvote_request_free(request);
375	return NULL;
376	}
377
378	return request;
379	}
380
381	vote_t gcvote_restore(appdata_t appdata, cache_t *cache) {
382	/* load data from disk */
383	char *filename = g_strdup_printf("%s%s/gcvote.xml",
384	appdata->image_path,
385	cache->id);
386
387	printf("gcvote: trying to restore from %s\n", filename);
388
389	/* no such file? */
390	if(!g_file_test(filename, G_FILE_TEST_EXISTS)) {
391	printf("gcvote: no such file\n");
392	free(filename);
393	return NULL;
394	}
395
396	LIBXML_TEST_VERSION;
397	xmlDoc *doc = xmlReadFile(filename, NULL, 0);
398
399	if(doc == NULL) {
400	printf("gcvote: error, could not parse file %s\n", filename);
401	free(filename);
402	return NULL;
403	}
404
405	free(filename);
406
407	/* in this case this will sure only return one result */
408	gcvote_t *votes = parse_doc(doc);
409
410	if(!votes) {
411	printf("gcvote: error, no vote found\n");
412	free(filename);
413	return NULL;
414	}
415
416	vote_t *vote = g_new0(vote_t, 1);
417	vote->quality = votes->quality;
418	vote->votes = votes->votes;
419
420	printf("gcvote: found vote %d/%d\n", vote->quality, vote->votes);
421
422	gcvotes_free(votes);
423
424	return vote;
425	}