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__anon94e24a9b0111::CacheInfo22 CacheInfo(uint32_t t, CPDF_Stream* stream) : time(t), pStream(stream) {}
23
24 uint32_t time;
25 CPDF_Stream* pStream;
26
operator <__anon94e24a9b0111::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,const CPDF_RenderStatus * pRenderStatus,bool bStdCS)75 bool CPDF_PageRenderCache::StartGetCachedBitmap(
76 const RetainPtr<CPDF_Image>& pImage,
77 const CPDF_RenderStatus* pRenderStatus,
78 bool bStdCS) {
79 CPDF_Stream* pStream = pImage->GetStream();
80 const auto it = m_ImageCache.find(pStream);
81 m_bCurFindCache = it != m_ImageCache.end();
82 if (m_bCurFindCache) {
83 m_pCurImageCacheEntry = it->second.get();
84 } else {
85 m_pCurImageCacheEntry = pdfium::MakeUnique<CPDF_ImageCacheEntry>(
86 m_pPage->GetDocument(), pImage);
87 }
88 CPDF_DIB::LoadState ret = m_pCurImageCacheEntry->StartGetCachedBitmap(
89 m_pPage->m_pPageResources.Get(), pRenderStatus, bStdCS);
90 if (ret == CPDF_DIB::LoadState::kContinue)
91 return true;
92
93 m_nTimeCount++;
94 if (!m_bCurFindCache)
95 m_ImageCache[pStream] = m_pCurImageCacheEntry.Release();
96
97 if (ret == CPDF_DIB::LoadState::kFail)
98 m_nCacheSize += m_pCurImageCacheEntry->EstimateSize();
99
100 return false;
101 }
102
Continue(PauseIndicatorIface * pPause,CPDF_RenderStatus * pRenderStatus)103 bool CPDF_PageRenderCache::Continue(PauseIndicatorIface* pPause,
104 CPDF_RenderStatus* pRenderStatus) {
105 bool ret = m_pCurImageCacheEntry->Continue(pPause, pRenderStatus);
106 if (ret)
107 return true;
108
109 m_nTimeCount++;
110 if (!m_bCurFindCache) {
111 m_ImageCache[m_pCurImageCacheEntry->GetImage()->GetStream()] =
112 m_pCurImageCacheEntry.Release();
113 }
114 m_nCacheSize += m_pCurImageCacheEntry->EstimateSize();
115 return false;
116 }
117
ResetBitmapForImage(const RetainPtr<CPDF_Image> & pImage)118 void CPDF_PageRenderCache::ResetBitmapForImage(
119 const RetainPtr<CPDF_Image>& pImage) {
120 CPDF_ImageCacheEntry* pEntry;
121 CPDF_Stream* pStream = pImage->GetStream();
122 const auto it = m_ImageCache.find(pStream);
123 if (it == m_ImageCache.end())
124 return;
125
126 pEntry = it->second.get();
127 m_nCacheSize -= pEntry->EstimateSize();
128 pEntry->Reset();
129 m_nCacheSize += pEntry->EstimateSize();
130 }
131