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 /*

  * Copyright 2010 The Android Open Source Project

  *

  * Use of this source code is governed by a BSD-style license that can be

  * found in the LICENSE file.

  */

 #include "SkPDFCatalog.h"

 #include "SkPDFTypes.h"

 #include "SkStream.h"

 #include "SkTypes.h"

 SkPDFCatalog::SkPDFCatalog(SkPDFDocument::Flags flags)

     : fFirstPageCount(0),

       fNextObjNum(1),

       fNextFirstPageObjNum(0),

       fDocumentFlags(flags) {

 }

 SkPDFCatalog::~SkPDFCatalog() {

     fSubstituteResourcesRemaining.safeUnrefAll();

     fSubstituteResourcesFirstPage.safeUnrefAll();

 }

 SkPDFObject* SkPDFCatalog::addObject(SkPDFObject* obj, bool onFirstPage) {

     if (findObjectIndex(obj) != -1) {  // object already added

         return obj;

     }

     SkASSERT(fNextFirstPageObjNum == 0);

     if (onFirstPage) {

         fFirstPageCount++;

     }

     struct Rec newEntry(obj, onFirstPage);

     fCatalog.append(1, &newEntry);

     return obj;

 }

 size_t SkPDFCatalog::setFileOffset(SkPDFObject* obj, off_t offset) {

     int objIndex = assignObjNum(obj) - 1;

     SkASSERT(fCatalog[objIndex].fObjNumAssigned);

     SkASSERT(fCatalog[objIndex].fFileOffset == 0);

     fCatalog[objIndex].fFileOffset = offset;

     return getSubstituteObject(obj)->getOutputSize(this, true);

 }

 void SkPDFCatalog::emitObjectNumber(SkWStream* stream, SkPDFObject* obj) {

     stream->writeDecAsText(assignObjNum(obj));

     stream->writeText(" 0");  // Generation number is always 0.

 }

 size_t SkPDFCatalog::getObjectNumberSize(SkPDFObject* obj) {

     SkDynamicMemoryWStream buffer;

     emitObjectNumber(&buffer, obj);

     return buffer.getOffset();

 }

 int SkPDFCatalog::findObjectIndex(SkPDFObject* obj) const {

     for (int i = 0; i < fCatalog.count(); i++) {

         if (fCatalog[i].fObject == obj) {

             return i;

         }

     }

     // If it's not in the main array, check if it's a substitute object.

     for (int i = 0; i < fSubstituteMap.count(); ++i) {

         if (fSubstituteMap[i].fSubstitute == obj) {

             return findObjectIndex(fSubstituteMap[i].fOriginal);

         }

     }

     return -1;

 }

 int SkPDFCatalog::assignObjNum(SkPDFObject* obj) {

     int pos = findObjectIndex(obj);

     // If this assert fails, it means you probably forgot to add an object

     // to the resource list.

     SkASSERT(pos >= 0);

     uint32_t currentIndex = pos;

     if (fCatalog[currentIndex].fObjNumAssigned) {

         return currentIndex + 1;

     }

     // First assignment.

     if (fNextFirstPageObjNum == 0) {

         fNextFirstPageObjNum = fCatalog.count() - fFirstPageCount + 1;

     }

     uint32_t objNum;

     if (fCatalog[currentIndex].fOnFirstPage) {

         objNum = fNextFirstPageObjNum;

         fNextFirstPageObjNum++;

     } else {

         objNum = fNextObjNum;

         fNextObjNum++;

     }

     // When we assign an object an object number, we put it in that array

     // offset (minus 1 because object number 0 is reserved).

     SkASSERT(!fCatalog[objNum - 1].fObjNumAssigned);

     if (objNum - 1 != currentIndex) {

         SkTSwap(fCatalog[objNum - 1], fCatalog[currentIndex]);

     }

     fCatalog[objNum - 1].fObjNumAssigned = true;

     return objNum;

 }

 int32_t SkPDFCatalog::emitXrefTable(SkWStream* stream, bool firstPage) {

     int first = -1;

     int last = fCatalog.count() - 1;

     // TODO(vandebo): Support linearized format.

     // int last = fCatalog.count() - fFirstPageCount - 1;

     // if (firstPage) {

     //     first = fCatalog.count() - fFirstPageCount;

     //     last = fCatalog.count() - 1;

     // }

     stream->writeText("xref\n");

     stream->writeDecAsText(first + 1);

     stream->writeText(" ");

     stream->writeDecAsText(last - first + 1);

     stream->writeText("\n");

     if (first == -1) {

         stream->writeText("0000000000 65535 f \n");

         first++;

     }

     for (int i = first; i <= last; i++) {

         // For 32 bits platforms, the maximum offset has to fit within off_t

         // which is a 32 bits signed integer on these platforms.

         SkDEBUGCODE(static const off_t kMaxOff = SK_MaxS32;)

         SkASSERT(fCatalog[i].fFileOffset > 0);

         SkASSERT(fCatalog[i].fFileOffset < kMaxOff);

         stream->writeBigDecAsText(fCatalog[i].fFileOffset, 10);

         stream->writeText(" 00000 n \n");

     }

     return fCatalog.count() + 1;

 }

 void SkPDFCatalog::setSubstitute(SkPDFObject* original,

                                  SkPDFObject* substitute) {

 #if defined(SK_DEBUG)

     // Sanity check: is the original already in substitute list?

     for (int i = 0; i < fSubstituteMap.count(); ++i) {

         if (original == fSubstituteMap[i].fSubstitute ||

             original == fSubstituteMap[i].fOriginal) {

             SkASSERT(false);

             return;

         }

     }

 #endif

     // Check if the original is on first page.

     bool onFirstPage = false;

     for (int i = 0; i < fCatalog.count(); ++i) {

         if (fCatalog[i].fObject == original) {

             onFirstPage = fCatalog[i].fOnFirstPage;

             break;

         }

 #if defined(SK_DEBUG)

         if (i == fCatalog.count() - 1) {

             SkASSERT(false);  // original not in catalog

             return;

         }

 #endif

     }

     SubstituteMapping newMapping(original, substitute);

     fSubstituteMap.append(1, &newMapping);

     // Add resource objects of substitute object to catalog.

     SkTSet<SkPDFObject*>* targetSet = getSubstituteList(onFirstPage);

     SkTSet<SkPDFObject*> newResourceObjects;

     newMapping.fSubstitute->getResources(*targetSet, &newResourceObjects);

     for (int i = 0; i < newResourceObjects.count(); ++i) {

         addObject(newResourceObjects[i], onFirstPage);

     }

     // mergeInto returns the number of duplicates.

     // If there are duplicates, there is a bug and we mess ref counting.

     SkDEBUGCODE(int duplicates =) targetSet->mergeInto(newResourceObjects);

     SkASSERT(duplicates == 0);

 }

 SkPDFObject* SkPDFCatalog::getSubstituteObject(SkPDFObject* object) {

     for (int i = 0; i < fSubstituteMap.count(); ++i) {

         if (object == fSubstituteMap[i].fOriginal) {

             return fSubstituteMap[i].fSubstitute;

         }

     }

     return object;

 }

 off_t SkPDFCatalog::setSubstituteResourcesOffsets(off_t fileOffset,

                                                   bool firstPage) {

     SkTSet<SkPDFObject*>* targetSet = getSubstituteList(firstPage);

     off_t offsetSum = fileOffset;

     for (int i = 0; i < targetSet->count(); ++i) {

         offsetSum += setFileOffset((*targetSet)[i], offsetSum);

     }

     return offsetSum - fileOffset;

 }

 void SkPDFCatalog::emitSubstituteResources(SkWStream *stream, bool firstPage) {

     SkTSet<SkPDFObject*>* targetSet = getSubstituteList(firstPage);

     for (int i = 0; i < targetSet->count(); ++i) {

         (*targetSet)[i]->emit(stream, this, true);

     }

 }

 SkTSet<SkPDFObject*>* SkPDFCatalog::getSubstituteList(bool firstPage) {

     return firstPage ? &fSubstituteResourcesFirstPage :

                        &fSubstituteResourcesRemaining;

 }