//===- CVRecord.h -----------------------------------------------*- 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
 
//
 
//===----------------------------------------------------------------------===//
 
 
 
#ifndef LLVM_DEBUGINFO_CODEVIEW_CVRECORD_H
 
#define LLVM_DEBUGINFO_CODEVIEW_CVRECORD_H
 
 
 
#include "llvm/ADT/ArrayRef.h"
 
#include "llvm/DebugInfo/CodeView/CodeView.h"
 
#include "llvm/DebugInfo/CodeView/CodeViewError.h"
 
#include "llvm/DebugInfo/CodeView/RecordSerialization.h"
 
#include "llvm/Support/BinaryStreamReader.h"
 
#include "llvm/Support/BinaryStreamRef.h"
 
#include "llvm/Support/Endian.h"
 
#include "llvm/Support/Error.h"
 
#include <cstdint>
 
 
 
namespace llvm {
 
 
 
namespace codeview {
 
 
 
/// CVRecord is a fat pointer (base + size pair) to a symbol or type record.
 
/// Carrying the size separately instead of trusting the size stored in the
 
/// record prefix provides some extra safety and flexibility.
 
template <typename Kind> class CVRecord {
 
public:
 
  CVRecord() = default;
 
 
 
  CVRecord(ArrayRef<uint8_t> Data) : RecordData(Data) {}
 
 
 
  CVRecord(const RecordPrefix *P, size_t Size)
 
      : RecordData(reinterpret_cast<const uint8_t *>(P), Size) {}
 
 
 
  bool valid() const { return kind() != Kind(0); }
 
 
 
  uint32_t length() const { return RecordData.size(); }
 
 
 
  Kind kind() const {
 
    if (RecordData.size() < sizeof(RecordPrefix))
 
      return Kind(0);
 
    return static_cast<Kind>(static_cast<uint16_t>(
 
        reinterpret_cast<const RecordPrefix *>(RecordData.data())->RecordKind));
 
  }
 
 
 
  ArrayRef<uint8_t> data() const { return RecordData; }
 
 
 
  StringRef str_data() const {
 
    return StringRef(reinterpret_cast<const char *>(RecordData.data()),
 
                     RecordData.size());
 
  }
 
 
 
  ArrayRef<uint8_t> content() const {
 
    return RecordData.drop_front(sizeof(RecordPrefix));
 
  }
 
 
 
  ArrayRef<uint8_t> RecordData;
 
};
 
 
 
// There are two kinds of codeview records: type and symbol records.
 
using CVType = CVRecord<TypeLeafKind>;
 
using CVSymbol = CVRecord<SymbolKind>;
 
 
 
template <typename Record, typename Func>
 
Error forEachCodeViewRecord(ArrayRef<uint8_t> StreamBuffer, Func F) {
 
  while (!StreamBuffer.empty()) {
 
    if (StreamBuffer.size() < sizeof(RecordPrefix))
 
      return make_error<CodeViewError>(cv_error_code::corrupt_record);
 
 
 
    const RecordPrefix *Prefix =
 
        reinterpret_cast<const RecordPrefix *>(StreamBuffer.data());
 
 
 
    size_t RealLen = Prefix->RecordLen + 2;
 
    if (StreamBuffer.size() < RealLen)
 
      return make_error<CodeViewError>(cv_error_code::corrupt_record);
 
 
 
    ArrayRef<uint8_t> Data = StreamBuffer.take_front(RealLen);
 
    StreamBuffer = StreamBuffer.drop_front(RealLen);
 
 
 
    Record R(Data);
 
    if (auto EC = F(R))
 
      return EC;
 
  }
 
  return Error::success();
 
}
 
 
 
/// Read a complete record from a stream at a random offset.
 
template <typename Kind>
 
inline Expected<CVRecord<Kind>> readCVRecordFromStream(BinaryStreamRef Stream,
 
                                                       uint32_t Offset) {
 
  const RecordPrefix *Prefix = nullptr;
 
  BinaryStreamReader Reader(Stream);
 
  Reader.setOffset(Offset);
 
 
 
  if (auto EC = Reader.readObject(Prefix))
 
    return std::move(EC);
 
  if (Prefix->RecordLen < 2)
 
    return make_error<CodeViewError>(cv_error_code::corrupt_record);
 
 
 
  Reader.setOffset(Offset);
 
  ArrayRef<uint8_t> RawData;
 
  if (auto EC = Reader.readBytes(RawData, Prefix->RecordLen + sizeof(uint16_t)))
 
    return std::move(EC);
 
  return codeview::CVRecord<Kind>(RawData);
 
}
 
 
 
} // end namespace codeview
 
 
 
template <typename Kind>
 
struct VarStreamArrayExtractor<codeview::CVRecord<Kind>> {
 
  Error operator()(BinaryStreamRef Stream, uint32_t &Len,
 
                   codeview::CVRecord<Kind> &Item) {
 
    auto ExpectedRec = codeview::readCVRecordFromStream<Kind>(Stream, 0);
 
    if (!ExpectedRec)
 
      return ExpectedRec.takeError();
 
    Item = *ExpectedRec;
 
    Len = ExpectedRec->length();
 
    return Error::success();
 
  }
 
};
 
 
 
namespace codeview {
 
using CVSymbolArray = VarStreamArray<CVSymbol>;
 
using CVTypeArray = VarStreamArray<CVType>;
 
using CVTypeRange = iterator_range<CVTypeArray::Iterator>;
 
} // namespace codeview
 
 
 
} // end namespace llvm
 
 
 
#endif // LLVM_DEBUGINFO_CODEVIEW_CVRECORD_H