1 // Copyright 2016 PDFium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
6
7 #include "core/fpdfapi/render/cpdf_pagerendercache.h"
8
9 #include <algorithm>
10 #include <vector>
11
12 #include "core/fpdfapi/page/cpdf_image.h"
13 #include "core/fpdfapi/page/cpdf_page.h"
14 #include "core/fpdfapi/render/cpdf_imagecacheentry.h"
15 #include "core/fpdfapi/render/cpdf_renderstatus.h"
16 #include "core/fxge/dib/cfx_dibitmap.h"
17 #include "third_party/base/ptr_util.h"
18
19 namespace {
20
21 struct CacheInfo {
CacheInfo__anon21e0f99a0111::CacheInfo22 CacheInfo(uint32_t t, CPDF_Stream* stream) : time(t), pStream(stream) {}
23
24 uint32_t time;
25 CPDF_Stream* pStream;
26
operator <__anon21e0f99a0111::CacheInfo27 bool operator<(const CacheInfo& other) const { return time < other.time; }
28 };
29
30 } // namespace
31
CPDF_PageRenderCache(CPDF_Page * pPage)32 CPDF_PageRenderCache::CPDF_PageRenderCache(CPDF_Page* pPage) : m_pPage(pPage) {}
33
34 CPDF_PageRenderCache::~CPDF_PageRenderCache() = default;
35
CacheOptimization(int32_t dwLimitCacheSize)36 void CPDF_PageRenderCache::CacheOptimization(int32_t dwLimitCacheSize) {
37 if (m_nCacheSize <= (uint32_t)dwLimitCacheSize)
38 return;
39
40 size_t nCount = m_ImageCache.size();
41 std::vector<CacheInfo> cache_info;
42 cache_info.reserve(nCount);
43 for (const auto& it : m_ImageCache) {
44 cache_info.emplace_back(it.second->GetTimeCount(),
45 it.second->GetImage()->GetStream());
46 }
47 std::sort(cache_info.begin(), cache_info.end());
48
49 // Check if time value is about to roll over and reset all entries.
50 // The comparision is legal because uint32_t is an unsigned type.
51 uint32_t nTimeCount = m_nTimeCount;
52 if (nTimeCount + 1 < nTimeCount) {
53 for (size_t i = 0; i < nCount; i++)
54 m_ImageCache[cache_info[i].pStream]->m_dwTimeCount = i;
55 m_nTimeCount = nCount;
56 }
57
58 size_t i = 0;
59 while (i + 15 < nCount)
60 ClearImageCacheEntry(cache_info[i++].pStream);
61
62 while (i < nCount && m_nCacheSize > (uint32_t)dwLimitCacheSize)
63 ClearImageCacheEntry(cache_info[i++].pStream);
64 }
65
ClearImageCacheEntry(CPDF_Stream * pStream)66 void CPDF_PageRenderCache::ClearImageCacheEntry(CPDF_Stream* pStream) {
67 auto it = m_ImageCache.find(pStream);
68 if (it == m_ImageCache.end())
69 return;
70
71 m_nCacheSize -= it->second->EstimateSize();
72 m_ImageCache.erase(it);
73 }
74
StartGetCachedBitmap(const RetainPtr<CPDF_Image> & pImage,bool bStdCS,uint32_t GroupFamily,bool bLoadMask,CPDF_RenderStatus * pRenderStatus)75 bool CPDF_PageRenderCache::StartGetCachedBitmap(
76 const RetainPtr<CPDF_Image>& pImage,
77 bool bStdCS,
78 uint32_t GroupFamily,
79 bool bLoadMask,
80 CPDF_RenderStatus* pRenderStatus) {
81 CPDF_Stream* pStream = pImage->GetStream();
82 const auto it = m_ImageCache.find(pStream);
83 m_bCurFindCache = it != m_ImageCache.end();
84 if (m_bCurFindCache) {
85 m_pCurImageCacheEntry = it->second.get();
86 } else {
87 m_pCurImageCacheEntry = pdfium::MakeUnique<CPDF_ImageCacheEntry>(
88 m_pPage->GetDocument(), pImage);
89 }
90 CPDF_DIB::LoadState ret = m_pCurImageCacheEntry->StartGetCachedBitmap(
91 pRenderStatus->GetFormResource(), m_pPage->m_pPageResources.Get(), bStdCS,
92 GroupFamily, bLoadMask, pRenderStatus);
93 if (ret == CPDF_DIB::LoadState::kContinue)
94 return true;
95
96 m_nTimeCount++;
97 if (!m_bCurFindCache)
98 m_ImageCache[pStream] = m_pCurImageCacheEntry.Release();
99
100 if (ret == CPDF_DIB::LoadState::kFail)
101 m_nCacheSize += m_pCurImageCacheEntry->EstimateSize();
102
103 return false;
104 }
105
Continue(PauseIndicatorIface * pPause,CPDF_RenderStatus * pRenderStatus)106 bool CPDF_PageRenderCache::Continue(PauseIndicatorIface* pPause,
107 CPDF_RenderStatus* pRenderStatus) {
108 bool ret = m_pCurImageCacheEntry->Continue(pPause, pRenderStatus);
109 if (ret)
110 return true;
111
112 m_nTimeCount++;
113 if (!m_bCurFindCache) {
114 m_ImageCache[m_pCurImageCacheEntry->GetImage()->GetStream()] =
115 m_pCurImageCacheEntry.Release();
116 }
117 m_nCacheSize += m_pCurImageCacheEntry->EstimateSize();
118 return false;
119 }
120
ResetBitmapForImage(const RetainPtr<CPDF_Image> & pImage)121 void CPDF_PageRenderCache::ResetBitmapForImage(
122 const RetainPtr<CPDF_Image>& pImage) {
123 CPDF_ImageCacheEntry* pEntry;
124 CPDF_Stream* pStream = pImage->GetStream();
125 const auto it = m_ImageCache.find(pStream);
126 if (it == m_ImageCache.end())
127 return;
128
129 pEntry = it->second.get();
130 m_nCacheSize -= pEntry->EstimateSize();
131 pEntry->Reset();
132 m_nCacheSize += pEntry->EstimateSize();
133 }
134