1 //===- PublicsStream.cpp - PDB Public Symbol Stream -----------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // The data structures defined in this file are based on the reference 11 // implementation which is available at 12 // https://github.com/Microsoft/microsoft-pdb/blob/master/PDB/dbi/gsi.h 13 // 14 // When you are reading the reference source code, you'd find the 15 // information below useful. 16 // 17 // - ppdb1->m_fMinimalDbgInfo seems to be always true. 18 // - SMALLBUCKETS macro is defined. 19 // 20 // The reference doesn't compile, so I learned just by reading code. 21 // It's not guaranteed to be correct. 22 // 23 //===----------------------------------------------------------------------===// 24 25 #include "llvm/DebugInfo/PDB/Native/PublicsStream.h" 26 #include "GSI.h" 27 #include "llvm/ADT/iterator_range.h" 28 #include "llvm/DebugInfo/CodeView/SymbolRecord.h" 29 #include "llvm/DebugInfo/MSF/MappedBlockStream.h" 30 #include "llvm/DebugInfo/PDB/Native/PDBFile.h" 31 #include "llvm/DebugInfo/PDB/Native/RawError.h" 32 #include "llvm/DebugInfo/PDB/Native/SymbolStream.h" 33 #include "llvm/Support/BinaryStreamReader.h" 34 #include "llvm/Support/Endian.h" 35 #include "llvm/Support/Error.h" 36 #include <algorithm> 37 #include <cstdint> 38 39 using namespace llvm; 40 using namespace llvm::msf; 41 using namespace llvm::support; 42 using namespace llvm::pdb; 43 44 PublicsStream::PublicsStream(std::unique_ptr<MappedBlockStream> Stream) 45 : Stream(std::move(Stream)) {} 46 47 PublicsStream::~PublicsStream() = default; 48 49 uint32_t PublicsStream::getSymHash() const { return Header->SymHash; } 50 uint32_t PublicsStream::getAddrMap() const { return Header->AddrMap; } 51 52 // Publics stream contains fixed-size headers and a serialized hash table. 53 // This implementation is not complete yet. It reads till the end of the 54 // stream so that we verify the stream is at least not corrupted. However, 55 // we skip over the hash table which we believe contains information about 56 // public symbols. 57 Error PublicsStream::reload() { 58 BinaryStreamReader Reader(*Stream); 59 60 // Check stream size. 61 if (Reader.bytesRemaining() < 62 sizeof(PublicsStreamHeader) + sizeof(GSIHashHeader)) 63 return make_error<RawError>(raw_error_code::corrupt_file, 64 "Publics Stream does not contain a header."); 65 66 // Read PSGSIHDR struct. 67 if (Reader.readObject(Header)) 68 return make_error<RawError>(raw_error_code::corrupt_file, 69 "Publics Stream does not contain a header."); 70 71 // Read the hash table. 72 if (auto E = PublicsTable.read(Reader)) 73 return E; 74 75 // Something called "address map" follows. 76 uint32_t NumAddressMapEntries = Header->AddrMap / sizeof(uint32_t); 77 if (auto EC = Reader.readArray(AddressMap, NumAddressMapEntries)) 78 return joinErrors(std::move(EC), 79 make_error<RawError>(raw_error_code::corrupt_file, 80 "Could not read an address map.")); 81 82 // Something called "thunk map" follows. 83 if (auto EC = Reader.readArray(ThunkMap, Header->NumThunks)) 84 return joinErrors(std::move(EC), 85 make_error<RawError>(raw_error_code::corrupt_file, 86 "Could not read a thunk map.")); 87 88 // Something called "section map" follows. 89 if (Reader.bytesRemaining() > 0) { 90 if (auto EC = Reader.readArray(SectionOffsets, Header->NumSections)) 91 return joinErrors(std::move(EC), 92 make_error<RawError>(raw_error_code::corrupt_file, 93 "Could not read a section map.")); 94 } 95 96 if (Reader.bytesRemaining() > 0) 97 return make_error<RawError>(raw_error_code::corrupt_file, 98 "Corrupted publics stream."); 99 return Error::success(); 100 } 101