• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 
2 /*
3  * Copyright 2010 The Android Open Source Project
4  *
5  * Use of this source code is governed by a BSD-style license that can be
6  * found in the LICENSE file.
7  */
8 
9 
10 #include "SkPDFCatalog.h"
11 #include "SkPDFTypes.h"
12 #include "SkStream.h"
13 #include "SkTypes.h"
14 
SkPDFCatalog(SkPDFDocument::Flags flags)15 SkPDFCatalog::SkPDFCatalog(SkPDFDocument::Flags flags)
16     : fFirstPageCount(0),
17       fNextObjNum(1),
18       fNextFirstPageObjNum(0),
19       fDocumentFlags(flags) {
20 }
21 
~SkPDFCatalog()22 SkPDFCatalog::~SkPDFCatalog() {
23     fSubstituteResourcesRemaining.safeUnrefAll();
24     fSubstituteResourcesFirstPage.safeUnrefAll();
25 }
26 
addObject(SkPDFObject * obj,bool onFirstPage)27 SkPDFObject* SkPDFCatalog::addObject(SkPDFObject* obj, bool onFirstPage) {
28     if (findObjectIndex(obj) != -1) {  // object already added
29         return obj;
30     }
31     SkASSERT(fNextFirstPageObjNum == 0);
32     if (onFirstPage) {
33         fFirstPageCount++;
34     }
35 
36     struct Rec newEntry(obj, onFirstPage);
37     fCatalog.append(1, &newEntry);
38     return obj;
39 }
40 
setFileOffset(SkPDFObject * obj,off_t offset)41 size_t SkPDFCatalog::setFileOffset(SkPDFObject* obj, off_t offset) {
42     int objIndex = assignObjNum(obj) - 1;
43     SkASSERT(fCatalog[objIndex].fObjNumAssigned);
44     SkASSERT(fCatalog[objIndex].fFileOffset == 0);
45     fCatalog[objIndex].fFileOffset = offset;
46 
47     return getSubstituteObject(obj)->getOutputSize(this, true);
48 }
49 
emitObjectNumber(SkWStream * stream,SkPDFObject * obj)50 void SkPDFCatalog::emitObjectNumber(SkWStream* stream, SkPDFObject* obj) {
51     stream->writeDecAsText(assignObjNum(obj));
52     stream->writeText(" 0");  // Generation number is always 0.
53 }
54 
getObjectNumberSize(SkPDFObject * obj)55 size_t SkPDFCatalog::getObjectNumberSize(SkPDFObject* obj) {
56     SkDynamicMemoryWStream buffer;
57     emitObjectNumber(&buffer, obj);
58     return buffer.getOffset();
59 }
60 
findObjectIndex(SkPDFObject * obj) const61 int SkPDFCatalog::findObjectIndex(SkPDFObject* obj) const {
62     for (int i = 0; i < fCatalog.count(); i++) {
63         if (fCatalog[i].fObject == obj) {
64             return i;
65         }
66     }
67     // If it's not in the main array, check if it's a substitute object.
68     for (int i = 0; i < fSubstituteMap.count(); ++i) {
69         if (fSubstituteMap[i].fSubstitute == obj) {
70             return findObjectIndex(fSubstituteMap[i].fOriginal);
71         }
72     }
73     return -1;
74 }
75 
assignObjNum(SkPDFObject * obj)76 int SkPDFCatalog::assignObjNum(SkPDFObject* obj) {
77     int pos = findObjectIndex(obj);
78     // If this assert fails, it means you probably forgot to add an object
79     // to the resource list.
80     SkASSERT(pos >= 0);
81     uint32_t currentIndex = pos;
82     if (fCatalog[currentIndex].fObjNumAssigned) {
83         return currentIndex + 1;
84     }
85 
86     // First assignment.
87     if (fNextFirstPageObjNum == 0) {
88         fNextFirstPageObjNum = fCatalog.count() - fFirstPageCount + 1;
89     }
90 
91     uint32_t objNum;
92     if (fCatalog[currentIndex].fOnFirstPage) {
93         objNum = fNextFirstPageObjNum;
94         fNextFirstPageObjNum++;
95     } else {
96         objNum = fNextObjNum;
97         fNextObjNum++;
98     }
99 
100     // When we assign an object an object number, we put it in that array
101     // offset (minus 1 because object number 0 is reserved).
102     SkASSERT(!fCatalog[objNum - 1].fObjNumAssigned);
103     if (objNum - 1 != currentIndex) {
104         SkTSwap(fCatalog[objNum - 1], fCatalog[currentIndex]);
105     }
106     fCatalog[objNum - 1].fObjNumAssigned = true;
107     return objNum;
108 }
109 
emitXrefTable(SkWStream * stream,bool firstPage)110 int32_t SkPDFCatalog::emitXrefTable(SkWStream* stream, bool firstPage) {
111     int first = -1;
112     int last = fCatalog.count() - 1;
113     // TODO(vandebo): Support linearized format.
114     // int last = fCatalog.count() - fFirstPageCount - 1;
115     // if (firstPage) {
116     //     first = fCatalog.count() - fFirstPageCount;
117     //     last = fCatalog.count() - 1;
118     // }
119 
120     stream->writeText("xref\n");
121     stream->writeDecAsText(first + 1);
122     stream->writeText(" ");
123     stream->writeDecAsText(last - first + 1);
124     stream->writeText("\n");
125 
126     if (first == -1) {
127         stream->writeText("0000000000 65535 f \n");
128         first++;
129     }
130     for (int i = first; i <= last; i++) {
131         // For 32 bits platforms, the maximum offset has to fit within off_t
132         // which is a 32 bits signed integer on these platforms.
133         SkDEBUGCODE(static const off_t kMaxOff = SK_MaxS32;)
134         SkASSERT(fCatalog[i].fFileOffset > 0);
135         SkASSERT(fCatalog[i].fFileOffset < kMaxOff);
136         stream->writeBigDecAsText(fCatalog[i].fFileOffset, 10);
137         stream->writeText(" 00000 n \n");
138     }
139 
140     return fCatalog.count() + 1;
141 }
142 
setSubstitute(SkPDFObject * original,SkPDFObject * substitute)143 void SkPDFCatalog::setSubstitute(SkPDFObject* original,
144                                  SkPDFObject* substitute) {
145 #if defined(SK_DEBUG)
146     // Sanity check: is the original already in substitute list?
147     for (int i = 0; i < fSubstituteMap.count(); ++i) {
148         if (original == fSubstituteMap[i].fSubstitute ||
149             original == fSubstituteMap[i].fOriginal) {
150             SkASSERT(false);
151             return;
152         }
153     }
154 #endif
155     // Check if the original is on first page.
156     bool onFirstPage = false;
157     for (int i = 0; i < fCatalog.count(); ++i) {
158         if (fCatalog[i].fObject == original) {
159             onFirstPage = fCatalog[i].fOnFirstPage;
160             break;
161         }
162 #if defined(SK_DEBUG)
163         if (i == fCatalog.count() - 1) {
164             SkASSERT(false);  // original not in catalog
165             return;
166         }
167 #endif
168     }
169 
170     SubstituteMapping newMapping(original, substitute);
171     fSubstituteMap.append(1, &newMapping);
172 
173     // Add resource objects of substitute object to catalog.
174     SkTSet<SkPDFObject*>* targetSet = getSubstituteList(onFirstPage);
175     SkTSet<SkPDFObject*> newResourceObjects;
176     newMapping.fSubstitute->getResources(*targetSet, &newResourceObjects);
177     for (int i = 0; i < newResourceObjects.count(); ++i) {
178         addObject(newResourceObjects[i], onFirstPage);
179     }
180     // mergeInto returns the number of duplicates.
181     // If there are duplicates, there is a bug and we mess ref counting.
182     SkDEBUGCODE(int duplicates =) targetSet->mergeInto(newResourceObjects);
183     SkASSERT(duplicates == 0);
184 }
185 
getSubstituteObject(SkPDFObject * object)186 SkPDFObject* SkPDFCatalog::getSubstituteObject(SkPDFObject* object) {
187     for (int i = 0; i < fSubstituteMap.count(); ++i) {
188         if (object == fSubstituteMap[i].fOriginal) {
189             return fSubstituteMap[i].fSubstitute;
190         }
191     }
192     return object;
193 }
194 
setSubstituteResourcesOffsets(off_t fileOffset,bool firstPage)195 off_t SkPDFCatalog::setSubstituteResourcesOffsets(off_t fileOffset,
196                                                   bool firstPage) {
197     SkTSet<SkPDFObject*>* targetSet = getSubstituteList(firstPage);
198     off_t offsetSum = fileOffset;
199     for (int i = 0; i < targetSet->count(); ++i) {
200         offsetSum += setFileOffset((*targetSet)[i], offsetSum);
201     }
202     return offsetSum - fileOffset;
203 }
204 
emitSubstituteResources(SkWStream * stream,bool firstPage)205 void SkPDFCatalog::emitSubstituteResources(SkWStream *stream, bool firstPage) {
206     SkTSet<SkPDFObject*>* targetSet = getSubstituteList(firstPage);
207     for (int i = 0; i < targetSet->count(); ++i) {
208         (*targetSet)[i]->emit(stream, this, true);
209     }
210 }
211 
getSubstituteList(bool firstPage)212 SkTSet<SkPDFObject*>* SkPDFCatalog::getSubstituteList(bool firstPage) {
213     return firstPage ? &fSubstituteResourcesFirstPage :
214                        &fSubstituteResourcesRemaining;
215 }
216