1 //===- PDBFileBuilder.cpp - PDB File Creation -------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "llvm/DebugInfo/PDB/Native/PDBFileBuilder.h"
10 #include "llvm/DebugInfo/CodeView/CodeView.h"
11 #include "llvm/DebugInfo/CodeView/GUID.h"
12 #include "llvm/DebugInfo/MSF/MSFBuilder.h"
13 #include "llvm/DebugInfo/MSF/MSFCommon.h"
14 #include "llvm/DebugInfo/MSF/MappedBlockStream.h"
15 #include "llvm/DebugInfo/PDB/Native/DbiStreamBuilder.h"
16 #include "llvm/DebugInfo/PDB/Native/GSIStreamBuilder.h"
17 #include "llvm/DebugInfo/PDB/Native/InfoStreamBuilder.h"
18 #include "llvm/DebugInfo/PDB/Native/PDBStringTableBuilder.h"
19 #include "llvm/DebugInfo/PDB/Native/RawConstants.h"
20 #include "llvm/DebugInfo/PDB/Native/RawError.h"
21 #include "llvm/DebugInfo/PDB/Native/RawTypes.h"
22 #include "llvm/DebugInfo/PDB/Native/TpiStreamBuilder.h"
23 #include "llvm/Support/BinaryStreamWriter.h"
24 #include "llvm/Support/CRC.h"
25 #include "llvm/Support/Path.h"
26 #include "llvm/Support/xxhash.h"
27 
28 #include <ctime>
29 
30 using namespace llvm;
31 using namespace llvm::codeview;
32 using namespace llvm::msf;
33 using namespace llvm::pdb;
34 using namespace llvm::support;
35 
36 namespace llvm {
37 class WritableBinaryStream;
38 }
39 
PDBFileBuilder(BumpPtrAllocator & Allocator)40 PDBFileBuilder::PDBFileBuilder(BumpPtrAllocator &Allocator)
41     : Allocator(Allocator), InjectedSourceHashTraits(Strings),
42       InjectedSourceTable(2) {}
43 
44 PDBFileBuilder::~PDBFileBuilder() = default;
45 
initialize(uint32_t BlockSize)46 Error PDBFileBuilder::initialize(uint32_t BlockSize) {
47   auto ExpectedMsf = MSFBuilder::create(Allocator, BlockSize);
48   if (!ExpectedMsf)
49     return ExpectedMsf.takeError();
50   Msf = std::make_unique<MSFBuilder>(std::move(*ExpectedMsf));
51   return Error::success();
52 }
53 
getMsfBuilder()54 MSFBuilder &PDBFileBuilder::getMsfBuilder() { return *Msf; }
55 
getInfoBuilder()56 InfoStreamBuilder &PDBFileBuilder::getInfoBuilder() {
57   if (!Info)
58     Info = std::make_unique<InfoStreamBuilder>(*Msf, NamedStreams);
59   return *Info;
60 }
61 
getDbiBuilder()62 DbiStreamBuilder &PDBFileBuilder::getDbiBuilder() {
63   if (!Dbi)
64     Dbi = std::make_unique<DbiStreamBuilder>(*Msf);
65   return *Dbi;
66 }
67 
getTpiBuilder()68 TpiStreamBuilder &PDBFileBuilder::getTpiBuilder() {
69   if (!Tpi)
70     Tpi = std::make_unique<TpiStreamBuilder>(*Msf, StreamTPI);
71   return *Tpi;
72 }
73 
getIpiBuilder()74 TpiStreamBuilder &PDBFileBuilder::getIpiBuilder() {
75   if (!Ipi)
76     Ipi = std::make_unique<TpiStreamBuilder>(*Msf, StreamIPI);
77   return *Ipi;
78 }
79 
getStringTableBuilder()80 PDBStringTableBuilder &PDBFileBuilder::getStringTableBuilder() {
81   return Strings;
82 }
83 
getGsiBuilder()84 GSIStreamBuilder &PDBFileBuilder::getGsiBuilder() {
85   if (!Gsi)
86     Gsi = std::make_unique<GSIStreamBuilder>(*Msf);
87   return *Gsi;
88 }
89 
allocateNamedStream(StringRef Name,uint32_t Size)90 Expected<uint32_t> PDBFileBuilder::allocateNamedStream(StringRef Name,
91                                                        uint32_t Size) {
92   auto ExpectedStream = Msf->addStream(Size);
93   if (ExpectedStream)
94     NamedStreams.set(Name, *ExpectedStream);
95   return ExpectedStream;
96 }
97 
addNamedStream(StringRef Name,StringRef Data)98 Error PDBFileBuilder::addNamedStream(StringRef Name, StringRef Data) {
99   Expected<uint32_t> ExpectedIndex = allocateNamedStream(Name, Data.size());
100   if (!ExpectedIndex)
101     return ExpectedIndex.takeError();
102   assert(NamedStreamData.count(*ExpectedIndex) == 0);
103   NamedStreamData[*ExpectedIndex] = std::string(Data);
104   return Error::success();
105 }
106 
addInjectedSource(StringRef Name,std::unique_ptr<MemoryBuffer> Buffer)107 void PDBFileBuilder::addInjectedSource(StringRef Name,
108                                        std::unique_ptr<MemoryBuffer> Buffer) {
109   // Stream names must be exact matches, since they get looked up in a hash
110   // table and the hash value is dependent on the exact contents of the string.
111   // link.exe lowercases a path and converts / to \, so we must do the same.
112   SmallString<64> VName;
113   sys::path::native(Name.lower(), VName, sys::path::Style::windows_backslash);
114 
115   uint32_t NI = getStringTableBuilder().insert(Name);
116   uint32_t VNI = getStringTableBuilder().insert(VName);
117 
118   InjectedSourceDescriptor Desc;
119   Desc.Content = std::move(Buffer);
120   Desc.NameIndex = NI;
121   Desc.VNameIndex = VNI;
122   Desc.StreamName = "/src/files/";
123 
124   Desc.StreamName += VName;
125 
126   InjectedSources.push_back(std::move(Desc));
127 }
128 
finalizeMsfLayout()129 Error PDBFileBuilder::finalizeMsfLayout() {
130 
131   if (Ipi && Ipi->getRecordCount() > 0) {
132     // In theory newer PDBs always have an ID stream, but by saying that we're
133     // only going to *really* have an ID stream if there is at least one ID
134     // record, we leave open the opportunity to test older PDBs such as those
135     // that don't have an ID stream.
136     auto &Info = getInfoBuilder();
137     Info.addFeature(PdbRaw_FeatureSig::VC140);
138   }
139 
140   uint32_t StringsLen = Strings.calculateSerializedSize();
141 
142   Expected<uint32_t> SN = allocateNamedStream("/LinkInfo", 0);
143   if (!SN)
144     return SN.takeError();
145 
146   if (Gsi) {
147     if (auto EC = Gsi->finalizeMsfLayout())
148       return EC;
149     if (Dbi) {
150       Dbi->setPublicsStreamIndex(Gsi->getPublicsStreamIndex());
151       Dbi->setGlobalsStreamIndex(Gsi->getGlobalsStreamIndex());
152       Dbi->setSymbolRecordStreamIndex(Gsi->getRecordStreamIndex());
153     }
154   }
155   if (Tpi) {
156     if (auto EC = Tpi->finalizeMsfLayout())
157       return EC;
158   }
159   if (Dbi) {
160     if (auto EC = Dbi->finalizeMsfLayout())
161       return EC;
162   }
163   SN = allocateNamedStream("/names", StringsLen);
164   if (!SN)
165     return SN.takeError();
166 
167   if (Ipi) {
168     if (auto EC = Ipi->finalizeMsfLayout())
169       return EC;
170   }
171 
172   // Do this last, since it relies on the named stream map being complete, and
173   // that can be updated by previous steps in the finalization.
174   if (Info) {
175     if (auto EC = Info->finalizeMsfLayout())
176       return EC;
177   }
178 
179   if (!InjectedSources.empty()) {
180     for (const auto &IS : InjectedSources) {
181       JamCRC CRC(0);
182       CRC.update(arrayRefFromStringRef(IS.Content->getBuffer()));
183 
184       SrcHeaderBlockEntry Entry;
185       ::memset(&Entry, 0, sizeof(SrcHeaderBlockEntry));
186       Entry.Size = sizeof(SrcHeaderBlockEntry);
187       Entry.FileSize = IS.Content->getBufferSize();
188       Entry.FileNI = IS.NameIndex;
189       Entry.VFileNI = IS.VNameIndex;
190       Entry.ObjNI = 1;
191       Entry.IsVirtual = 0;
192       Entry.Version =
193           static_cast<uint32_t>(PdbRaw_SrcHeaderBlockVer::SrcVerOne);
194       Entry.CRC = CRC.getCRC();
195       StringRef VName = getStringTableBuilder().getStringForId(IS.VNameIndex);
196       InjectedSourceTable.set_as(VName, std::move(Entry),
197                                  InjectedSourceHashTraits);
198     }
199 
200     uint32_t SrcHeaderBlockSize =
201         sizeof(SrcHeaderBlockHeader) +
202         InjectedSourceTable.calculateSerializedLength();
203     SN = allocateNamedStream("/src/headerblock", SrcHeaderBlockSize);
204     if (!SN)
205       return SN.takeError();
206     for (const auto &IS : InjectedSources) {
207       SN = allocateNamedStream(IS.StreamName, IS.Content->getBufferSize());
208       if (!SN)
209         return SN.takeError();
210     }
211   }
212 
213   // Do this last, since it relies on the named stream map being complete, and
214   // that can be updated by previous steps in the finalization.
215   if (Info) {
216     if (auto EC = Info->finalizeMsfLayout())
217       return EC;
218   }
219 
220   return Error::success();
221 }
222 
getNamedStreamIndex(StringRef Name) const223 Expected<uint32_t> PDBFileBuilder::getNamedStreamIndex(StringRef Name) const {
224   uint32_t SN = 0;
225   if (!NamedStreams.get(Name, SN))
226     return llvm::make_error<pdb::RawError>(raw_error_code::no_stream);
227   return SN;
228 }
229 
commitSrcHeaderBlock(WritableBinaryStream & MsfBuffer,const msf::MSFLayout & Layout)230 void PDBFileBuilder::commitSrcHeaderBlock(WritableBinaryStream &MsfBuffer,
231                                           const msf::MSFLayout &Layout) {
232   assert(!InjectedSourceTable.empty());
233 
234   uint32_t SN = cantFail(getNamedStreamIndex("/src/headerblock"));
235   auto Stream = WritableMappedBlockStream::createIndexedStream(
236       Layout, MsfBuffer, SN, Allocator);
237   BinaryStreamWriter Writer(*Stream);
238 
239   SrcHeaderBlockHeader Header;
240   ::memset(&Header, 0, sizeof(Header));
241   Header.Version = static_cast<uint32_t>(PdbRaw_SrcHeaderBlockVer::SrcVerOne);
242   Header.Size = Writer.bytesRemaining();
243 
244   cantFail(Writer.writeObject(Header));
245   cantFail(InjectedSourceTable.commit(Writer));
246 
247   assert(Writer.bytesRemaining() == 0);
248 }
249 
commitInjectedSources(WritableBinaryStream & MsfBuffer,const msf::MSFLayout & Layout)250 void PDBFileBuilder::commitInjectedSources(WritableBinaryStream &MsfBuffer,
251                                            const msf::MSFLayout &Layout) {
252   if (InjectedSourceTable.empty())
253     return;
254 
255   commitSrcHeaderBlock(MsfBuffer, Layout);
256 
257   for (const auto &IS : InjectedSources) {
258     uint32_t SN = cantFail(getNamedStreamIndex(IS.StreamName));
259 
260     auto SourceStream = WritableMappedBlockStream::createIndexedStream(
261         Layout, MsfBuffer, SN, Allocator);
262     BinaryStreamWriter SourceWriter(*SourceStream);
263     assert(SourceWriter.bytesRemaining() == IS.Content->getBufferSize());
264     cantFail(SourceWriter.writeBytes(
265         arrayRefFromStringRef(IS.Content->getBuffer())));
266   }
267 }
268 
commit(StringRef Filename,codeview::GUID * Guid)269 Error PDBFileBuilder::commit(StringRef Filename, codeview::GUID *Guid) {
270   assert(!Filename.empty());
271   if (auto EC = finalizeMsfLayout())
272     return EC;
273 
274   MSFLayout Layout;
275   Expected<FileBufferByteStream> ExpectedMsfBuffer =
276       Msf->commit(Filename, Layout);
277   if (!ExpectedMsfBuffer)
278     return ExpectedMsfBuffer.takeError();
279   FileBufferByteStream Buffer = std::move(*ExpectedMsfBuffer);
280 
281   auto ExpectedSN = getNamedStreamIndex("/names");
282   if (!ExpectedSN)
283     return ExpectedSN.takeError();
284 
285   auto NS = WritableMappedBlockStream::createIndexedStream(
286       Layout, Buffer, *ExpectedSN, Allocator);
287   BinaryStreamWriter NSWriter(*NS);
288   if (auto EC = Strings.commit(NSWriter))
289     return EC;
290 
291   for (const auto &NSE : NamedStreamData) {
292     if (NSE.second.empty())
293       continue;
294 
295     auto NS = WritableMappedBlockStream::createIndexedStream(
296         Layout, Buffer, NSE.first, Allocator);
297     BinaryStreamWriter NSW(*NS);
298     if (auto EC = NSW.writeBytes(arrayRefFromStringRef(NSE.second)))
299       return EC;
300   }
301 
302   if (Info) {
303     if (auto EC = Info->commit(Layout, Buffer))
304       return EC;
305   }
306 
307   if (Dbi) {
308     if (auto EC = Dbi->commit(Layout, Buffer))
309       return EC;
310   }
311 
312   if (Tpi) {
313     if (auto EC = Tpi->commit(Layout, Buffer))
314       return EC;
315   }
316 
317   if (Ipi) {
318     if (auto EC = Ipi->commit(Layout, Buffer))
319       return EC;
320   }
321 
322   if (Gsi) {
323     if (auto EC = Gsi->commit(Layout, Buffer))
324       return EC;
325   }
326 
327   auto InfoStreamBlocks = Layout.StreamMap[StreamPDB];
328   assert(!InfoStreamBlocks.empty());
329   uint64_t InfoStreamFileOffset =
330       blockToOffset(InfoStreamBlocks.front(), Layout.SB->BlockSize);
331   InfoStreamHeader *H = reinterpret_cast<InfoStreamHeader *>(
332       Buffer.getBufferStart() + InfoStreamFileOffset);
333 
334   commitInjectedSources(Buffer, Layout);
335 
336   // Set the build id at the very end, after every other byte of the PDB
337   // has been written.
338   if (Info->hashPDBContentsToGUID()) {
339     // Compute a hash of all sections of the output file.
340     uint64_t Digest =
341         xxHash64({Buffer.getBufferStart(), Buffer.getBufferEnd()});
342 
343     H->Age = 1;
344 
345     memcpy(H->Guid.Guid, &Digest, 8);
346     // xxhash only gives us 8 bytes, so put some fixed data in the other half.
347     memcpy(H->Guid.Guid + 8, "LLD PDB.", 8);
348 
349     // Put the hash in the Signature field too.
350     H->Signature = static_cast<uint32_t>(Digest);
351 
352     // Return GUID to caller.
353     memcpy(Guid, H->Guid.Guid, 16);
354   } else {
355     H->Age = Info->getAge();
356     H->Guid = Info->getGuid();
357     std::optional<uint32_t> Sig = Info->getSignature();
358     H->Signature = Sig ? *Sig : time(nullptr);
359   }
360 
361   return Buffer.commit();
362 }
363