llvm-project/llvm/lib/DebugInfo/PDB/Native/PDBStringTable.cpp

141 lines
4.5 KiB
C++

//===- PDBStringTable.cpp - PDB String Table ---------------------*- C++-*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "llvm/DebugInfo/PDB/Native/PDBStringTable.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/DebugInfo/PDB/Native/Hash.h"
#include "llvm/DebugInfo/PDB/Native/RawError.h"
#include "llvm/DebugInfo/PDB/Native/RawTypes.h"
#include "llvm/Support/BinaryStreamReader.h"
#include "llvm/Support/Endian.h"
using namespace llvm;
using namespace llvm::support;
using namespace llvm::pdb;
uint32_t PDBStringTable::getByteSize() const { return Header->ByteSize; }
uint32_t PDBStringTable::getNameCount() const { return NameCount; }
uint32_t PDBStringTable::getHashVersion() const { return Header->HashVersion; }
uint32_t PDBStringTable::getSignature() const { return Header->Signature; }
Error PDBStringTable::readHeader(BinaryStreamReader &Reader) {
if (auto EC = Reader.readObject(Header))
return EC;
if (Header->Signature != PDBStringTableSignature)
return make_error<RawError>(raw_error_code::corrupt_file,
"Invalid hash table signature");
if (Header->HashVersion != 1 && Header->HashVersion != 2)
return make_error<RawError>(raw_error_code::corrupt_file,
"Unsupported hash version");
assert(Reader.bytesRemaining() == 0);
return Error::success();
}
Error PDBStringTable::readStrings(BinaryStreamReader &Reader) {
BinaryStreamRef Stream;
if (auto EC = Reader.readStreamRef(Stream))
return EC;
if (auto EC = Strings.initialize(Stream)) {
return joinErrors(std::move(EC),
make_error<RawError>(raw_error_code::corrupt_file,
"Invalid hash table byte length"));
}
assert(Reader.bytesRemaining() == 0);
return Error::success();
}
const codeview::DebugStringTableSubsectionRef &
PDBStringTable::getStringTable() const {
return Strings;
}
Error PDBStringTable::readHashTable(BinaryStreamReader &Reader) {
const support::ulittle32_t *HashCount;
if (auto EC = Reader.readObject(HashCount))
return EC;
if (auto EC = Reader.readArray(IDs, *HashCount)) {
return joinErrors(std::move(EC),
make_error<RawError>(raw_error_code::corrupt_file,
"Could not read bucket array"));
}
return Error::success();
}
Error PDBStringTable::readEpilogue(BinaryStreamReader &Reader) {
if (auto EC = Reader.readInteger(NameCount))
return EC;
assert(Reader.bytesRemaining() == 0);
return Error::success();
}
Error PDBStringTable::reload(BinaryStreamReader &Reader) {
BinaryStreamReader SectionReader;
std::tie(SectionReader, Reader) = Reader.split(sizeof(PDBStringTableHeader));
if (auto EC = readHeader(SectionReader))
return EC;
std::tie(SectionReader, Reader) = Reader.split(Header->ByteSize);
if (auto EC = readStrings(SectionReader))
return EC;
// We don't know how long the hash table is until we parse it, so let the
// function responsible for doing that figure it out.
if (auto EC = readHashTable(Reader))
return EC;
std::tie(SectionReader, Reader) = Reader.split(sizeof(uint32_t));
if (auto EC = readEpilogue(SectionReader))
return EC;
assert(Reader.bytesRemaining() == 0);
return Error::success();
}
Expected<StringRef> PDBStringTable::getStringForID(uint32_t ID) const {
return Strings.getString(ID);
}
Expected<uint32_t> PDBStringTable::getIDForString(StringRef Str) const {
uint32_t Hash =
(Header->HashVersion == 1) ? hashStringV1(Str) : hashStringV2(Str);
size_t Count = IDs.size();
uint32_t Start = Hash % Count;
for (size_t I = 0; I < Count; ++I) {
// The hash is just a starting point for the search, but if it
// doesn't work we should find the string no matter what, because
// we iterate the entire array.
uint32_t Index = (Start + I) % Count;
// If we find 0, it means the item isn't in the hash table.
uint32_t ID = IDs[Index];
if (ID == 0)
return make_error<RawError>(raw_error_code::no_entry);
auto ExpectedStr = getStringForID(ID);
if (!ExpectedStr)
return ExpectedStr.takeError();
if (*ExpectedStr == Str)
return ID;
}
return make_error<RawError>(raw_error_code::no_entry);
}
FixedStreamArray<support::ulittle32_t> PDBStringTable::name_ids() const {
return IDs;
}