dvdbookmarks.c

基于linux的DVD播放器程序

    return -1;
  }
  
  if((cur = xmlNewChild(cur, NULL, "bookmark", NULL)) == NULL) {
    return -1;
  } else {
    xmlDocPtr navdoc = NULL;
    xmlNodePtr navnode, navcopy;
    
    if((navdoc = xmlParseDoc(navstate)) == NULL) {
      return -1;
    }
   
    if((navnode = xmlDocGetRootElement(navdoc)) == NULL) {
      return -1;
    }
    
    if((navcopy = xmlDocCopyNode(navnode, bm->doc, 1)) == NULL) {
      return -1;
    }
    
    xmlFreeDoc(navdoc);
    
    xmlAddChild(cur, navcopy);
  }

  if(usercomment) {
    if((xmlNewTextChild(cur, NULL, "usercomment", usercomment)) == NULL) {
      return -1;
    }
  }

  if(appname && appinfo) {
    if((cur = xmlNewTextChild(cur, NULL, "appinfo", appinfo)) == NULL) {
      return -1;
    }
    xmlNewProp(cur, "appname", appname);    
  }
  
  return 0;						      
}


/**
 * Set the appinfo in a bookmark.
 *
 * @param bm Handle from DVDBookmarkOpen.
 * @param appname The name of your application here, you will
 * be able to supply application specific data in appinfo.
 * The appname "common" is used for standardized appinfo that all
 * players can read/use.
 * @param appinfo The appinfo data.
 * If there already is appinfo for the corresponding appname
 * it will be replaced.
 * If you pass NULL or a pointer to the empty string ""
 * the previous appinfo, if any, will be removed.
 * All char * should point to a nullterminated string.
 *
 * @return 0 on success, -1 on failure.
 */
int DVDBookmarkSetAppInfo(DVDBookmark_t *bm,
			  int nr,
			  const char *appname, const char *appinfo)
{
  xmlNodePtr cur;
  xmlNodePtr cur_bm;
  
  if(!bm || !appname) {
    return -1;
  }

  if((cur = xmlDocGetRootElement(bm->doc)) == NULL) {
    return -1;
  }

  cur_bm = get_bookmark(bm->doc, cur, nr);
  
  cur = cur_bm;
  if(cur == NULL) {
    return -1;
  }
  
  
  //if there is an appinfo with the same appname already remove it
  cur = cur->xmlChildrenNode;
  while(cur != NULL) {
    xmlNodePtr next = cur->next;
    if((!xmlStrcmp(cur->name, (const xmlChar *)"appinfo"))) {
      xmlChar *prop;
      if((prop = xmlGetProp(cur, "appname")) != NULL) {
	if(!xmlStrcmp(prop, (const xmlChar *)appname)) {
	  xmlFree(prop);
	  xmlUnlinkNode(cur);
	  xmlFreeNode(cur);
	} else {
	  xmlFree(prop);
	}
      }
    }
    cur = next;
  }

  cur = cur_bm;
  
  if(appinfo && (appinfo[0] != '\0')) {
    if((cur = xmlNewTextChild(cur, NULL, "appinfo", appinfo)) == NULL) {
      return -1;
    }
    xmlNewProp(cur, "appname", appname);    
  }

  return 0;						      
}

/**
 * Set the usercomment in a bookmark.
 *
 * @param bm Handle from DVDBookmarkOpen.
 * @param usercomment The comment.
 * If there already is a usercomment, it will be replaced.
 * Setting it to NULL or the empty string "" will remove a previous comment.
 * All char * should point to a nullterminated string.
 *
 * @return 0 on success, -1 on failure.
 */
int DVDBookmarkSetUserComment(DVDBookmark_t *bm, int nr,
			      const char *usercomment)
{
  xmlNodePtr cur;
  xmlNodePtr cur_bm;
  
  if(!bm) {
    return -1;
  }

  if((cur = xmlDocGetRootElement(bm->doc)) == NULL) {
    return -1;
  }

  cur_bm = get_bookmark(bm->doc, cur, nr);
  
  cur = cur_bm;
  if(cur == NULL) {
    return -1;
  }
  
  
  //if there is a usercomment already remove it
  cur = cur->xmlChildrenNode;
  while(cur != NULL) {
    xmlNodePtr next = cur->next;
    if((!xmlStrcmp(cur->name, (const xmlChar *)"usercomment"))) {
      xmlUnlinkNode(cur);
      xmlFreeNode(cur);
    }
    cur = next;
  }

  cur = cur_bm;
  
  if(usercomment && (usercomment[0] != '\0')) {
    if((cur = xmlNewTextChild(cur,NULL, "usercomment", usercomment)) == NULL) {
      return -1;
    }
  }
  
  return 0;						      
}

/**
 * Remove a bookmark for the current disc.
 *
 * @param bm Handle from DVDBookmarkOpen.
 * @param nr The specific bookmark in the list for this disc.
 * The nr is the same as in the DVDBookmarkGet function.
 * The numbering will change once you have removed a bookmark, the numbers
 * after the removed will decrease in value by one so there are no
 * gaps.
 * @return 0 on success, -1 on failure.
 */
int DVDBookmarkRemove(DVDBookmark_t *bm, int nr)
{
  xmlNodePtr cur;

  if(!bm || !(bm->doc) || (nr < 0)) {
    return -1;
  }
  
  if((cur = xmlDocGetRootElement(bm->doc)) == NULL) {
    return -1;
  }
  
  cur = get_bookmark(bm->doc, cur, nr);
  if(cur == NULL) {
    return -1;
  }
  
  xmlUnlinkNode(cur);
  xmlFreeNode(cur);

  return 0;
}


/**
 * Retrieve comment for the current disc.
 *
 * @param bm Handle from DVDBookmarkOpen.
 * @param disccomment This is where a pointer to the disccomment data
 * will be returned. It will be set if the call is succesfull otherwise
 * it will be undefined. You need to free() this when you are done with it.
 * In case nothing is returned it will be set to NULL;
 * @return 0 on success (though no data may be returned) -1 on failure
 */
int DVDBookmarkGetDiscComment(DVDBookmark_t *bm, char **disccomment)
{
  xmlNodePtr cur;
  xmlChar *data;
  if(!bm || !(bm->doc) || !disccomment) {
    return -1;
  }
  
  if((cur = xmlDocGetRootElement(bm->doc)) == NULL) {
    return -1;
  }

  cur = cur->xmlChildrenNode;
  while(cur != NULL) {
    if((!xmlStrcmp(cur->name, (const xmlChar *)"disccomment"))) {
      if(disccomment != NULL) {
	data = xmlNodeListGetString(bm->doc, cur->xmlChildrenNode, 1);
	if(data != NULL) {
	  *disccomment = strdup(data);
	  xmlFree(data);
	  return 0;
	}
      }
    }
    cur = cur->next;
  }
  *disccomment = NULL;
  return 0;
}


/**
 * Set comment for the current disc.
 *
 * @param bm Handle from DVDBookmarkOpen.
 * @param disccomment The disc comment
 */
int DVDBookmarkSetDiscComment(DVDBookmark_t *bm, const char *disccomment)
{
  xmlNodePtr cur, docroot;

  if(!bm || !(bm->doc) || !disccomment) {
    return -1;
  }
  
  if((docroot = xmlDocGetRootElement(bm->doc)) == NULL) {
    return -1;
  }
  cur = docroot;
  cur = cur->xmlChildrenNode;
  while(cur != NULL) {
    xmlNodePtr next = cur->next;
    if((!xmlStrcmp(cur->name, (const xmlChar *)"disccomment"))) {
      xmlUnlinkNode(cur);
      xmlFreeNode(cur);
    }
    cur = next;
  }
  
  cur = docroot;
  cur = cur->xmlChildrenNode;
  
  if(cur != NULL) {  
    xmlNodePtr newnode;
    if(((newnode =  xmlNewTextChild(docroot, NULL, 
				    "disccomment", disccomment))) == NULL) {
      return -1;
    }
    
    xmlGetNodePath(xmlAddPrevSibling(cur, newnode));
  } else {
    if((xmlNewTextChild(docroot, NULL, 
			"disccomment", disccomment)) == NULL) {
      return -1;
    }
  }
  
  return 0;
}


/**
 * Save the bookmark list for the current disc to file.
 * If the list doesn't contain any entries the file will be removed.
 *
 * @param bm Handle from DVDBookmarkOpen.
 * @param compressed If 1 the output file will be compressed and not human
 * readable. If 0 it will be normal indented text.
 * 0 is recommended if not disk space is very limited.
 * DVDBookmarkOpen opens and reads both compressed and uncompressed files.
 *
 * @return 0 on success, -1 on failure.
 */
int DVDBookmarkSave(DVDBookmark_t *bm, int compressed)
{
  xmlNodePtr cur;
  int n;

  if(!bm || !(bm->filename) || !(bm->doc)) {
    return -1;
  }
  if(compressed) {
    xmlSetDocCompressMode(bm->doc, 9);
  } else {
    xmlSetDocCompressMode(bm->doc, 0);
  }
  if(xmlSaveFormatFile(bm->filename, bm->doc, 1) == -1) {
    return -1;
  }

  if((cur = xmlDocGetRootElement(bm->doc)) == NULL) {
    return -1;
  }
  
  n = 0;
  cur = cur->xmlChildrenNode;
  while(cur != NULL) {
    if((!xmlStrcmp(cur->name, (const xmlChar *)"bookmark"))) {
      n++;
    }
    cur = cur->next;
  }
  
  if(n == 0) {
    unlink(bm->filename);
  }

  return 0;
}

/**
 * Close and free memory used for holding the bookmark list.
 * @param bm The handle to be freed. It cannot be used again.
 */
void DVDBookmarkClose(DVDBookmark_t *bm)
{
  if(!bm) {
    return;
  }
  if(bm->filename) {
    free(bm->filename);
    bm->filename = NULL;
  }
  
  if(bm->doc) {
    xmlFreeDoc(bm->doc);
    bm->doc = NULL;
  }
  
  free(bm);
  
  return;
}