src/graphics/GraphicsCache.cpp

   1 /**
   2  * \file GraphicsCache.cpp
   3  * This file is part of LyX, the document processor.
   4  * Licence details can be found in the file COPYING.
   5  *
   6  * \author Baruch Even
   7  * \author Angus Leeming
   8  *
   9  * Full author contact details are available in file CREDITS.
  10  */
  11
  12 #include <config.h>
  13
  14 #include "GraphicsCache.h"
  15 #include "GraphicsCacheItem.h"
  16 #include "GraphicsImage.h"
  17
  18 #include "debug.h"
  19
  20 #include "support/filetools.h"
  21
  22 #include <map>
  23
  24 using std::string;
  25
  26
  27 namespace lyx {
  28
  29 using support::FileName;
  30
  31 namespace graphics {
  32
  33 /** The cache contains one item per file, so use a map to find the
  34  *  cache item quickly by filename.
  35  */
  36 typedef std::map<FileName, Cache::ItemPtr> CacheType;
  37
  38 class Cache::Impl {
  39 public:
  40         ///
  41         CacheType cache;
  42 };
  43
  44
  45 Cache & Cache::get()
  46 {
  47         // Now return the cache
  48         static Cache singleton;
  49         return singleton;
  50 }
  51
  52
  53 Cache::Cache()
  54         : pimpl_(new Impl)
  55 {}
  56
  57
  58 Cache::~Cache()
  59 {}
  60
  61
  62 std::vector<string> Cache::loadableFormats() const
  63 {
  64         return Image::loadableFormats();
  65 }
  66
  67
  68 void Cache::add(FileName const & file) const
  69 {
  70         // Is the file in the cache already?
  71         if (inCache(file)) {
  72                 LYXERR(Debug::GRAPHICS) << "Cache::add(" << file << "):\n"
  73                                         << "The file is already in the cache."
  74                                         << std::endl;
  75                 return;
  76         }
  77
  78         pimpl_->cache[file] = ItemPtr(new CacheItem(file));
  79 }
  80
  81
  82 void Cache::remove(FileName const & file) const
  83 {
  84         CacheType::iterator it = pimpl_->cache.find(file);
  85         if (it == pimpl_->cache.end())
  86                 return;
  87
  88         ItemPtr & item = it->second;
  89
  90         if (item.use_count() == 1) {
  91                 // The graphics file is in the cache, but nothing else
  92                 // references it.
  93                 pimpl_->cache.erase(it);
  94         }
  95 }
  96
  97
  98 bool Cache::inCache(FileName const & file) const
  99 {
 100         return pimpl_->cache.find(file) != pimpl_->cache.end();
 101 }
 102
 103
 104 Cache::ItemPtr const Cache::item(FileName const & file) const
 105 {
 106         CacheType::const_iterator it = pimpl_->cache.find(file);
 107         if (it == pimpl_->cache.end())
 108                 return ItemPtr();
 109
 110         return it->second;
 111 }
 112
 113 } // namespace graphics
 114 } // namespace lyx