140 lines · cpp
1//===- PDBStringTable.cpp - PDB String Table ---------------------*- 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-exception6//7//===----------------------------------------------------------------------===//8 9#include "llvm/DebugInfo/PDB/Native/PDBStringTable.h"10 11#include "llvm/DebugInfo/PDB/Native/Hash.h"12#include "llvm/DebugInfo/PDB/Native/RawError.h"13#include "llvm/DebugInfo/PDB/Native/RawTypes.h"14#include "llvm/Support/BinaryStreamReader.h"15#include "llvm/Support/Endian.h"16 17using namespace llvm;18using namespace llvm::support;19using namespace llvm::pdb;20 21uint32_t PDBStringTable::getByteSize() const { return Header->ByteSize; }22uint32_t PDBStringTable::getNameCount() const { return NameCount; }23uint32_t PDBStringTable::getHashVersion() const { return Header->HashVersion; }24uint32_t PDBStringTable::getSignature() const { return Header->Signature; }25 26Error PDBStringTable::readHeader(BinaryStreamReader &Reader) {27 if (auto EC = Reader.readObject(Header))28 return EC;29 30 if (Header->Signature != PDBStringTableSignature)31 return make_error<RawError>(raw_error_code::corrupt_file,32 "Invalid hash table signature");33 if (Header->HashVersion != 1 && Header->HashVersion != 2)34 return make_error<RawError>(raw_error_code::corrupt_file,35 "Unsupported hash version");36 37 assert(Reader.bytesRemaining() == 0);38 return Error::success();39}40 41Error PDBStringTable::readStrings(BinaryStreamReader &Reader) {42 BinaryStreamRef Stream;43 if (auto EC = Reader.readStreamRef(Stream))44 return EC;45 46 if (auto EC = Strings.initialize(Stream)) {47 return joinErrors(std::move(EC),48 make_error<RawError>(raw_error_code::corrupt_file,49 "Invalid hash table byte length"));50 }51 52 assert(Reader.bytesRemaining() == 0);53 return Error::success();54}55 56const codeview::DebugStringTableSubsectionRef &57PDBStringTable::getStringTable() const {58 return Strings;59}60 61Error PDBStringTable::readHashTable(BinaryStreamReader &Reader) {62 const support::ulittle32_t *HashCount;63 if (auto EC = Reader.readObject(HashCount))64 return EC;65 66 if (auto EC = Reader.readArray(IDs, *HashCount)) {67 return joinErrors(std::move(EC),68 make_error<RawError>(raw_error_code::corrupt_file,69 "Could not read bucket array"));70 }71 72 return Error::success();73}74 75Error PDBStringTable::readEpilogue(BinaryStreamReader &Reader) {76 if (auto EC = Reader.readInteger(NameCount))77 return EC;78 79 assert(Reader.bytesRemaining() == 0);80 return Error::success();81}82 83Error PDBStringTable::reload(BinaryStreamReader &Reader) {84 85 BinaryStreamReader SectionReader;86 87 std::tie(SectionReader, Reader) = Reader.split(sizeof(PDBStringTableHeader));88 if (auto EC = readHeader(SectionReader))89 return EC;90 91 std::tie(SectionReader, Reader) = Reader.split(Header->ByteSize);92 if (auto EC = readStrings(SectionReader))93 return EC;94 95 // We don't know how long the hash table is until we parse it, so let the96 // function responsible for doing that figure it out.97 if (auto EC = readHashTable(Reader))98 return EC;99 100 std::tie(SectionReader, Reader) = Reader.split(sizeof(uint32_t));101 if (auto EC = readEpilogue(SectionReader))102 return EC;103 104 assert(Reader.bytesRemaining() == 0);105 return Error::success();106}107 108Expected<StringRef> PDBStringTable::getStringForID(uint32_t ID) const {109 return Strings.getString(ID);110}111 112Expected<uint32_t> PDBStringTable::getIDForString(StringRef Str) const {113 uint32_t Hash =114 (Header->HashVersion == 1) ? hashStringV1(Str) : hashStringV2(Str);115 size_t Count = IDs.size();116 uint32_t Start = Hash % Count;117 for (size_t I = 0; I < Count; ++I) {118 // The hash is just a starting point for the search, but if it119 // doesn't work we should find the string no matter what, because120 // we iterate the entire array.121 uint32_t Index = (Start + I) % Count;122 123 // If we find 0, it means the item isn't in the hash table.124 uint32_t ID = IDs[Index];125 if (ID == 0)126 return make_error<RawError>(raw_error_code::no_entry);127 auto ExpectedStr = getStringForID(ID);128 if (!ExpectedStr)129 return ExpectedStr.takeError();130 131 if (*ExpectedStr == Str)132 return ID;133 }134 return make_error<RawError>(raw_error_code::no_entry);135}136 137FixedStreamArray<support::ulittle32_t> PDBStringTable::name_ids() const {138 return IDs;139}140