1                 : /******************************************************************************
       2                 :  * $Id: cache.cpp 21880 2011-02-27 14:28:26Z rouault $
       3                 :  *
       4                 :  * Project:  WMS Client Driver
       5                 :  * Purpose:  Implementation of Dataset and RasterBand classes for WMS
       6                 :  *           and other similar services.
       7                 :  * Author:   Adam Nowacki, nowak@xpam.de
       8                 :  *
       9                 :  ******************************************************************************
      10                 :  * Copyright (c) 2007, Adam Nowacki
      11                 :  *
      12                 :  * Permission is hereby granted, free of charge, to any person obtaining a
      13                 :  * copy of this software and associated documentation files (the "Software"),
      14                 :  * to deal in the Software without restriction, including without limitation
      15                 :  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
      16                 :  * and/or sell copies of the Software, and to permit persons to whom the
      17                 :  * Software is furnished to do so, subject to the following conditions:
      18                 :  *
      19                 :  * The above copyright notice and this permission notice shall be included
      20                 :  * in all copies or substantial portions of the Software.
      21                 :  *
      22                 :  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
      23                 :  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
      24                 :  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
      25                 :  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
      26                 :  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
      27                 :  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
      28                 :  * DEALINGS IN THE SOFTWARE.
      29                 :  ****************************************************************************/
      30                 : 
      31                 : #include "stdinc.h"
      32                 : 
      33               4 : GDALWMSCache::GDALWMSCache() {
      34               4 :     m_cache_path = "./gdalwmscache";
      35               4 :     m_postfix = "";
      36               4 :     m_cache_depth = 2;
      37               4 : }
      38                 : 
      39               4 : GDALWMSCache::~GDALWMSCache() {
      40               4 : }
      41                 : 
      42               4 : CPLErr GDALWMSCache::Initialize(CPLXMLNode *config) {
      43               4 :     const char *cache_path = CPLGetXMLValue(config, "Path", "./gdalwmscache");
      44               4 :     m_cache_path = cache_path;
      45                 : 
      46               4 :     const char *cache_depth = CPLGetXMLValue(config, "Depth", "2");
      47               4 :     m_cache_depth = atoi(cache_depth);
      48                 : 
      49               4 :     const char *cache_extension = CPLGetXMLValue(config, "Extension", "");
      50               8 :     m_postfix = cache_extension;
      51                 : 
      52               4 :     return CE_None;
      53                 : }
      54                 : 
      55               2 : CPLErr GDALWMSCache::Write(const char *key, const CPLString &file_name) {
      56               2 :     CPLString cache_file(KeyToCacheFile(key));
      57                 :     //  printf("GDALWMSCache::Write(%s, %s) -> %s\n", key, file_name.c_str());
      58               2 :     if (CPLCopyFile(cache_file.c_str(), file_name.c_str()) != CE_None) {
      59               2 :         MakeDirs(cache_file.c_str());
      60               2 :         CPLCopyFile(cache_file.c_str(), file_name.c_str());
      61                 :     }
      62                 : 
      63               2 :     return CE_None;
      64                 : }
      65                 : 
      66               4 : CPLErr GDALWMSCache::Read(const char *key, CPLString *file_name) {
      67               4 :     CPLErr ret = CE_Failure;
      68               4 :     CPLString cache_file(KeyToCacheFile(key));
      69               4 :     VSILFILE* fp = VSIFOpenL(cache_file.c_str(), "rb");
      70               4 :     if (fp != NULL)
      71                 :     {
      72               2 :         VSIFCloseL(fp);
      73               2 :         *file_name = cache_file;
      74               2 :         ret = CE_None;
      75                 :     }
      76                 :     //    printf("GDALWMSCache::Read(...) -> %s\n", cache_file.c_str());
      77                 : 
      78               4 :     return ret;
      79                 : }
      80                 : 
      81               6 : CPLString GDALWMSCache::KeyToCacheFile(const char *key) {
      82               6 :     CPLString hash(MD5String(key));
      83               6 :     CPLString cache_file(m_cache_path);
      84                 : 
      85               6 :     if (cache_file.size() && (cache_file[cache_file.size() - 1] != '/')) cache_file.append(1, '/');
      86              18 :     for (int i = 0; i < m_cache_depth; ++i) {
      87              12 :         cache_file.append(1, hash[i]);
      88              12 :         cache_file.append(1, '/');
      89                 :     }
      90               6 :     cache_file.append(hash);
      91               6 :     cache_file.append(m_postfix);
      92               6 :     return cache_file;
      93                 : }