Line data    Source code

       1             : //===- PDBStringTable.cpp - PDB String Table ---------------------*- C++-*-===//
       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             : #include "llvm/DebugInfo/PDB/Native/PDBStringTable.h"
      11             : 
      12             : #include "llvm/ADT/ArrayRef.h"
      13             : #include "llvm/DebugInfo/PDB/Native/Hash.h"
      14             : #include "llvm/DebugInfo/PDB/Native/RawError.h"
      15             : #include "llvm/DebugInfo/PDB/Native/RawTypes.h"
      16             : #include "llvm/Support/BinaryStreamReader.h"
      17             : #include "llvm/Support/Endian.h"
      18             : 
      19             : using namespace llvm;
      20             : using namespace llvm::support;
      21             : using namespace llvm::pdb;
      22             : 
      23           2 : uint32_t PDBStringTable::getByteSize() const { return Header->ByteSize; }
      24           2 : uint32_t PDBStringTable::getNameCount() const { return NameCount; }
      25           4 : uint32_t PDBStringTable::getHashVersion() const { return Header->HashVersion; }
      26           2 : uint32_t PDBStringTable::getSignature() const { return Header->Signature; }
      27             : 
      28         164 : Error PDBStringTable::readHeader(BinaryStreamReader &Reader) {
      29         328 :   if (auto EC = Reader.readObject(Header))
      30             :     return EC;
      31             : 
      32         328 :   if (Header->Signature != PDBStringTableSignature)
      33             :     return make_error<RawError>(raw_error_code::corrupt_file,
      34             :                                 "Invalid hash table signature");
      35         164 :   if (Header->HashVersion != 1 && Header->HashVersion != 2)
      36             :     return make_error<RawError>(raw_error_code::corrupt_file,
      37             :                                 "Unsupported hash version");
      38             : 
      39             :   assert(Reader.bytesRemaining() == 0);
      40             :   return Error::success();
      41             : }
      42             : 
      43         164 : Error PDBStringTable::readStrings(BinaryStreamReader &Reader) {
      44             :   BinaryStreamRef Stream;
      45         328 :   if (auto EC = Reader.readStreamRef(Stream))
      46             :     return EC;
      47             : 
      48         492 :   if (auto EC = Strings.initialize(Stream)) {
      49             :     return joinErrors(std::move(EC),
      50           0 :                       make_error<RawError>(raw_error_code::corrupt_file,
      51           0 :                                            "Invalid hash table byte length"));
      52             :   }
      53             : 
      54             :   assert(Reader.bytesRemaining() == 0);
      55             :   return Error::success();
      56             : }
      57             : 
      58             : const codeview::DebugStringTableSubsectionRef &
      59          44 : PDBStringTable::getStringTable() const {
      60          44 :   return Strings;
      61             : }
      62             : 
      63         164 : Error PDBStringTable::readHashTable(BinaryStreamReader &Reader) {
      64             :   const support::ulittle32_t *HashCount;
      65         328 :   if (auto EC = Reader.readObject(HashCount))
      66             :     return EC;
      67             : 
      68         492 :   if (auto EC = Reader.readArray(IDs, *HashCount)) {
      69             :     return joinErrors(std::move(EC),
      70           0 :                       make_error<RawError>(raw_error_code::corrupt_file,
      71           0 :                                            "Could not read bucket array"));
      72             :   }
      73             : 
      74             :   return Error::success();
      75             : }
      76             : 
      77         164 : Error PDBStringTable::readEpilogue(BinaryStreamReader &Reader) {
      78         328 :   if (auto EC = Reader.readInteger(NameCount))
      79             :     return EC;
      80             : 
      81             :   assert(Reader.bytesRemaining() == 0);
      82             :   return Error::success();
      83             : }
      84             : 
      85         164 : Error PDBStringTable::reload(BinaryStreamReader &Reader) {
      86             : 
      87             :   BinaryStreamReader SectionReader;
      88             : 
      89         164 :   std::tie(SectionReader, Reader) = Reader.split(sizeof(PDBStringTableHeader));
      90         328 :   if (auto EC = readHeader(SectionReader))
      91             :     return EC;
      92             : 
      93         328 :   std::tie(SectionReader, Reader) = Reader.split(Header->ByteSize);
      94         328 :   if (auto EC = readStrings(SectionReader))
      95             :     return EC;
      96             : 
      97             :   // We don't know how long the hash table is until we parse it, so let the
      98             :   // function responsible for doing that figure it out.
      99         328 :   if (auto EC = readHashTable(Reader))
     100             :     return EC;
     101             : 
     102         164 :   std::tie(SectionReader, Reader) = Reader.split(sizeof(uint32_t));
     103         328 :   if (auto EC = readEpilogue(SectionReader))
     104             :     return EC;
     105             : 
     106             :   assert(Reader.bytesRemaining() == 0);
     107             :   return Error::success();
     108             : }
     109             : 
     110         307 : Expected<StringRef> PDBStringTable::getStringForID(uint32_t ID) const {
     111         307 :   return Strings.getString(ID);
     112             : }
     113             : 
     114           6 : Expected<uint32_t> PDBStringTable::getIDForString(StringRef Str) const {
     115             :   uint32_t Hash =
     116          12 :       (Header->HashVersion == 1) ? hashStringV1(Str) : hashStringV2(Str);
     117           6 :   size_t Count = IDs.size();
     118           6 :   uint32_t Start = Hash % Count;
     119           6 :   for (size_t I = 0; I < Count; ++I) {
     120             :     // The hash is just a starting point for the search, but if it
     121             :     // doesn't work we should find the string no matter what, because
     122             :     // we iterate the entire array.
     123           6 :     uint32_t Index = (Start + I) % Count;
     124             : 
     125             :     // If we find 0, it means the item isn't in the hash table.
     126           6 :     uint32_t ID = IDs[Index];
     127           6 :     if (ID == 0)
     128             :       return make_error<RawError>(raw_error_code::no_entry);
     129           6 :     auto ExpectedStr = getStringForID(ID);
     130           6 :     if (!ExpectedStr)
     131             :       return ExpectedStr.takeError();
     132             : 
     133             :     if (*ExpectedStr == Str)
     134             :       return ID;
     135             :   }
     136             :   return make_error<RawError>(raw_error_code::no_entry);
     137             : }
     138             : 
     139          25 : FixedStreamArray<support::ulittle32_t> PDBStringTable::name_ids() const {
     140          25 :   return IDs;
     141             : }