// Copyright 2014 PDFium Authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com #include "public/fpdf_flatten.h" #include <algorithm> #include <memory> #include <utility> #include <vector> #include "core/fpdfapi/page/cpdf_page.h" #include "core/fpdfapi/page/cpdf_pageobject.h" #include "core/fpdfapi/parser/cpdf_array.h" #include "core/fpdfapi/parser/cpdf_document.h" #include "core/fpdfapi/parser/cpdf_name.h" #include "core/fpdfapi/parser/cpdf_number.h" #include "core/fpdfapi/parser/cpdf_reference.h" #include "core/fpdfapi/parser/cpdf_stream.h" #include "core/fpdfapi/parser/cpdf_stream_acc.h" #include "core/fpdfdoc/cpdf_annot.h" #include "fpdfsdk/cpdfsdk_helpers.h" #include "third_party/base/stl_util.h" enum FPDF_TYPE { MAX, MIN }; enum FPDF_VALUE { TOP, LEFT, RIGHT, BOTTOM }; namespace { bool IsValidRect(const CFX_FloatRect& rect, const CFX_FloatRect& rcPage) { constexpr float kMinSize = 0.000001f; if (rect.IsEmpty() || rect.Width() < kMinSize || rect.Height() < kMinSize) return false; if (rcPage.IsEmpty()) return true; constexpr float kMinBorderSize = 10.000001f; return rect.left - rcPage.left >= -kMinBorderSize && rect.right - rcPage.right <= kMinBorderSize && rect.top - rcPage.top <= kMinBorderSize && rect.bottom - rcPage.bottom >= -kMinBorderSize; } void GetContentsRect(CPDF_Document* pDoc, CPDF_Dictionary* pDict, std::vector<CFX_FloatRect>* pRectArray) { auto pPDFPage = pdfium::MakeUnique<CPDF_Page>(pDoc, pDict, false); pPDFPage->ParseContent(); for (const auto& pPageObject : *pPDFPage->GetPageObjectList()) { CFX_FloatRect rc; rc.left = pPageObject->m_Left; rc.right = pPageObject->m_Right; rc.bottom = pPageObject->m_Bottom; rc.top = pPageObject->m_Top; if (IsValidRect(rc, pDict->GetRectFor("MediaBox"))) pRectArray->push_back(rc); } } void ParserStream(CPDF_Dictionary* pPageDic, CPDF_Dictionary* pStream, std::vector<CFX_FloatRect>* pRectArray, std::vector<CPDF_Dictionary*>* pObjectArray) { if (!pStream) return; CFX_FloatRect rect; if (pStream->KeyExist("Rect")) rect = pStream->GetRectFor("Rect"); else if (pStream->KeyExist("BBox")) rect = pStream->GetRectFor("BBox"); if (IsValidRect(rect, pPageDic->GetRectFor("MediaBox"))) pRectArray->push_back(rect); pObjectArray->push_back(pStream); } int ParserAnnots(CPDF_Document* pSourceDoc, CPDF_Dictionary* pPageDic, std::vector<CFX_FloatRect>* pRectArray, std::vector<CPDF_Dictionary*>* pObjectArray, int nUsage) { if (!pSourceDoc || !pPageDic) return FLATTEN_FAIL; GetContentsRect(pSourceDoc, pPageDic, pRectArray); CPDF_Array* pAnnots = pPageDic->GetArrayFor("Annots"); if (!pAnnots) return FLATTEN_NOTHINGTODO; for (const auto& pAnnot : *pAnnots) { CPDF_Dictionary* pAnnotDic = ToDictionary(pAnnot->GetDirect()); if (!pAnnotDic) continue; ByteString sSubtype = pAnnotDic->GetStringFor("Subtype"); if (sSubtype == "Popup") continue; int nAnnotFlag = pAnnotDic->GetIntegerFor("F"); if (nAnnotFlag & ANNOTFLAG_HIDDEN) continue; bool bParseStream; if (nUsage == FLAT_NORMALDISPLAY) bParseStream = !(nAnnotFlag & ANNOTFLAG_INVISIBLE); else bParseStream = !!(nAnnotFlag & ANNOTFLAG_PRINT); if (bParseStream) ParserStream(pPageDic, pAnnotDic, pRectArray, pObjectArray); } return FLATTEN_SUCCESS; } float GetMinMaxValue(const std::vector<CFX_FloatRect>& array, FPDF_TYPE type, FPDF_VALUE value) { if (array.empty()) return 0.0f; size_t nRects = array.size(); std::vector<float> pArray(nRects); switch (value) { case LEFT: for (size_t i = 0; i < nRects; i++) pArray[i] = array[i].left; break; case TOP: for (size_t i = 0; i < nRects; i++) pArray[i] = array[i].top; break; case RIGHT: for (size_t i = 0; i < nRects; i++) pArray[i] = array[i].right; break; case BOTTOM: for (size_t i = 0; i < nRects; i++) pArray[i] = array[i].bottom; break; default: NOTREACHED(); return 0.0f; } float fRet = pArray[0]; if (type == MAX) { for (size_t i = 1; i < nRects; i++) fRet = std::max(fRet, pArray[i]); } else { for (size_t i = 1; i < nRects; i++) fRet = std::min(fRet, pArray[i]); } return fRet; } CFX_FloatRect CalculateRect(std::vector<CFX_FloatRect>* pRectArray) { CFX_FloatRect rcRet; rcRet.left = GetMinMaxValue(*pRectArray, MIN, LEFT); rcRet.top = GetMinMaxValue(*pRectArray, MAX, TOP); rcRet.right = GetMinMaxValue(*pRectArray, MAX, RIGHT); rcRet.bottom = GetMinMaxValue(*pRectArray, MIN, BOTTOM); return rcRet; } uint32_t NewIndirectContentsStream(const ByteString& key, CPDF_Document* pDocument) { CPDF_Stream* pNewContents = pDocument->NewIndirect<CPDF_Stream>( nullptr, 0, pdfium::MakeUnique<CPDF_Dictionary>(pDocument->GetByteStringPool())); ByteString sStream = ByteString::Format("q 1 0 0 1 0 0 cm /%s Do Q", key.c_str()); pNewContents->SetData(sStream.raw_str(), sStream.GetLength()); return pNewContents->GetObjNum(); } void SetPageContents(const ByteString& key, CPDF_Dictionary* pPage, CPDF_Document* pDocument) { CPDF_Array* pContentsArray = nullptr; CPDF_Stream* pContentsStream = pPage->GetStreamFor("Contents"); if (!pContentsStream) { pContentsArray = pPage->GetArrayFor("Contents"); if (!pContentsArray) { if (!key.IsEmpty()) { pPage->SetNewFor<CPDF_Reference>( "Contents", pDocument, NewIndirectContentsStream(key, pDocument)); } return; } } pPage->ConvertToIndirectObjectFor("Contents", pDocument); if (!pContentsArray) { pContentsArray = pDocument->NewIndirect<CPDF_Array>(); auto pAcc = pdfium::MakeRetain<CPDF_StreamAcc>(pContentsStream); pAcc->LoadAllDataFiltered(); ByteString sStream = "q\n"; ByteString sBody = ByteString(pAcc->GetData(), pAcc->GetSize()); sStream = sStream + sBody + "\nQ"; pContentsStream->SetDataAndRemoveFilter(sStream.raw_str(), sStream.GetLength()); pContentsArray->AddNew<CPDF_Reference>(pDocument, pContentsStream->GetObjNum()); pPage->SetNewFor<CPDF_Reference>("Contents", pDocument, pContentsArray->GetObjNum()); } if (!key.IsEmpty()) { pContentsArray->AddNew<CPDF_Reference>( pDocument, NewIndirectContentsStream(key, pDocument)); } } CFX_Matrix GetMatrix(CFX_FloatRect rcAnnot, CFX_FloatRect rcStream, const CFX_Matrix& matrix) { if (rcStream.IsEmpty()) return CFX_Matrix(); rcStream = matrix.TransformRect(rcStream); rcStream.Normalize(); float a = rcAnnot.Width() / rcStream.Width(); float d = rcAnnot.Height() / rcStream.Height(); float e = rcAnnot.left - rcStream.left * a; float f = rcAnnot.bottom - rcStream.bottom * d; return CFX_Matrix(a, 0, 0, d, e, f); } } // namespace FPDF_EXPORT int FPDF_CALLCONV FPDFPage_Flatten(FPDF_PAGE page, int nFlag) { CPDF_Page* pPage = CPDFPageFromFPDFPage(page); if (!page) return FLATTEN_FAIL; CPDF_Document* pDocument = pPage->GetDocument(); CPDF_Dictionary* pPageDict = pPage->GetFormDict(); if (!pDocument || !pPageDict) return FLATTEN_FAIL; std::vector<CPDF_Dictionary*> ObjectArray; std::vector<CFX_FloatRect> RectArray; int iRet = ParserAnnots(pDocument, pPageDict, &RectArray, &ObjectArray, nFlag); if (iRet == FLATTEN_NOTHINGTODO || iRet == FLATTEN_FAIL) return iRet; CFX_FloatRect rcOriginalCB; CFX_FloatRect rcMerger = CalculateRect(&RectArray); CFX_FloatRect rcOriginalMB = pPageDict->GetRectFor("MediaBox"); if (pPageDict->KeyExist("CropBox")) rcOriginalMB = pPageDict->GetRectFor("CropBox"); if (rcOriginalMB.IsEmpty()) rcOriginalMB = CFX_FloatRect(0.0f, 0.0f, 612.0f, 792.0f); rcMerger.left = std::max(rcMerger.left, rcOriginalMB.left); rcMerger.right = std::min(rcMerger.right, rcOriginalMB.right); rcMerger.bottom = std::max(rcMerger.bottom, rcOriginalMB.bottom); rcMerger.top = std::min(rcMerger.top, rcOriginalMB.top); if (pPageDict->KeyExist("ArtBox")) rcOriginalCB = pPageDict->GetRectFor("ArtBox"); else rcOriginalCB = rcOriginalMB; if (!rcOriginalMB.IsEmpty()) pPageDict->SetRectFor("MediaBox", rcOriginalMB); if (!rcOriginalCB.IsEmpty()) pPageDict->SetRectFor("ArtBox", rcOriginalCB); CPDF_Dictionary* pRes = pPageDict->GetDictFor("Resources"); if (!pRes) pRes = pPageDict->SetNewFor<CPDF_Dictionary>("Resources"); CPDF_Stream* pNewXObject = pDocument->NewIndirect<CPDF_Stream>( nullptr, 0, pdfium::MakeUnique<CPDF_Dictionary>(pDocument->GetByteStringPool())); uint32_t dwObjNum = pNewXObject->GetObjNum(); CPDF_Dictionary* pPageXObject = pRes->GetDictFor("XObject"); if (!pPageXObject) pPageXObject = pRes->SetNewFor<CPDF_Dictionary>("XObject"); ByteString key; if (!ObjectArray.empty()) { int i = 0; while (i < INT_MAX) { ByteString sKey = ByteString::Format("FFT%d", i); if (!pPageXObject->KeyExist(sKey)) { key = sKey; break; } ++i; } } SetPageContents(key, pPageDict, pDocument); CPDF_Dictionary* pNewXORes = nullptr; if (!key.IsEmpty()) { pPageXObject->SetNewFor<CPDF_Reference>(key, pDocument, dwObjNum); CPDF_Dictionary* pNewOXbjectDic = pNewXObject->GetDict(); pNewXORes = pNewOXbjectDic->SetNewFor<CPDF_Dictionary>("Resources"); pNewOXbjectDic->SetNewFor<CPDF_Name>("Type", "XObject"); pNewOXbjectDic->SetNewFor<CPDF_Name>("Subtype", "Form"); pNewOXbjectDic->SetNewFor<CPDF_Number>("FormType", 1); CFX_FloatRect rcBBox = pPageDict->GetRectFor("ArtBox"); pNewOXbjectDic->SetRectFor("BBox", rcBBox); } for (size_t i = 0; i < ObjectArray.size(); ++i) { CPDF_Dictionary* pAnnotDic = ObjectArray[i]; if (!pAnnotDic) continue; CFX_FloatRect rcAnnot = pAnnotDic->GetRectFor("Rect"); rcAnnot.Normalize(); ByteString sAnnotState = pAnnotDic->GetStringFor("AS"); CPDF_Dictionary* pAnnotAP = pAnnotDic->GetDictFor("AP"); if (!pAnnotAP) continue; CPDF_Stream* pAPStream = pAnnotAP->GetStreamFor("N"); if (!pAPStream) { CPDF_Dictionary* pAPDic = pAnnotAP->GetDictFor("N"); if (!pAPDic) continue; if (!sAnnotState.IsEmpty()) { pAPStream = pAPDic->GetStreamFor(sAnnotState); } else { if (pAPDic->GetCount() > 0) { CPDF_Object* pFirstObj = pAPDic->begin()->second.get(); if (pFirstObj) { if (pFirstObj->IsReference()) pFirstObj = pFirstObj->GetDirect(); if (!pFirstObj->IsStream()) continue; pAPStream = pFirstObj->AsStream(); } } } } if (!pAPStream) continue; CPDF_Dictionary* pAPDic = pAPStream->GetDict(); CFX_FloatRect rcStream; if (pAPDic->KeyExist("Rect")) rcStream = pAPDic->GetRectFor("Rect"); else if (pAPDic->KeyExist("BBox")) rcStream = pAPDic->GetRectFor("BBox"); if (rcStream.IsEmpty()) continue; CPDF_Object* pObj = pAPStream; if (pObj->IsInline()) { std::unique_ptr<CPDF_Object> pNew = pObj->Clone(); pObj = pNew.get(); pDocument->AddIndirectObject(std::move(pNew)); } CPDF_Dictionary* pObjDic = pObj->GetDict(); if (pObjDic) { pObjDic->SetNewFor<CPDF_Name>("Type", "XObject"); pObjDic->SetNewFor<CPDF_Name>("Subtype", "Form"); } CPDF_Dictionary* pXObject = pNewXORes->GetDictFor("XObject"); if (!pXObject) pXObject = pNewXORes->SetNewFor<CPDF_Dictionary>("XObject"); ByteString sFormName = ByteString::Format("F%d", i); pXObject->SetNewFor<CPDF_Reference>(sFormName, pDocument, pObj->GetObjNum()); auto pAcc = pdfium::MakeRetain<CPDF_StreamAcc>(pNewXObject); pAcc->LoadAllDataFiltered(); ByteString sStream(pAcc->GetData(), pAcc->GetSize()); CFX_Matrix matrix = pAPDic->GetMatrixFor("Matrix"); CFX_Matrix m = GetMatrix(rcAnnot, rcStream, matrix); sStream += ByteString::Format("q %f 0 0 %f %f %f cm /%s Do Q\n", m.a, m.d, m.e, m.f, sFormName.c_str()); pNewXObject->SetDataAndRemoveFilter(sStream.raw_str(), sStream.GetLength()); } pPageDict->RemoveFor("Annots"); return FLATTEN_SUCCESS; }