Line data    Source code

       1             : //===- StreamReader.h - Reads bytes and objects from a stream ---*- 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             : #ifndef LLVM_DEBUGINFO_MSF_STREAMREADER_H
      11             : #define LLVM_DEBUGINFO_MSF_STREAMREADER_H
      12             : 
      13             : #include "llvm/ADT/ArrayRef.h"
      14             : #include "llvm/DebugInfo/Msf/MsfError.h"
      15             : #include "llvm/DebugInfo/Msf/StreamArray.h"
      16             : #include "llvm/DebugInfo/Msf/StreamInterface.h"
      17             : #include "llvm/DebugInfo/Msf/StreamRef.h"
      18             : #include "llvm/Support/Endian.h"
      19             : #include "llvm/Support/Error.h"
      20             : 
      21             : #include <string>
      22             : 
      23             : namespace llvm {
      24             : namespace msf {
      25             : 
      26             : class StreamReader {
      27             : public:
      28             :   StreamReader(ReadableStreamRef Stream);
      29             : 
      30             :   Error readLongestContiguousChunk(ArrayRef<uint8_t> &Buffer);
      31             :   Error readBytes(ArrayRef<uint8_t> &Buffer, uint32_t Size);
      32             :   Error readInteger(uint16_t &Dest);
      33             :   Error readInteger(uint32_t &Dest);
      34             :   Error readZeroString(StringRef &Dest);
      35             :   Error readFixedString(StringRef &Dest, uint32_t Length);
      36             :   Error readStreamRef(ReadableStreamRef &Ref);
      37             :   Error readStreamRef(ReadableStreamRef &Ref, uint32_t Length);
      38             : 
      39           3 :   template <typename T> Error readEnum(T &Dest) {
      40             :     typename std::underlying_type<T>::type N;
      41           9 :     if (auto EC = readInteger(N))
      42           0 :       return EC;
      43           3 :     Dest = static_cast<T>(N);
      44             :     return Error::success();
      45             :   }
      46             : 
      47       30417 :   template <typename T> Error readObject(const T *&Dest) {
      48       30417 :     ArrayRef<uint8_t> Buffer;
      49       91248 :     if (auto EC = readBytes(Buffer, sizeof(T)))
      50           6 :       return EC;
      51       30414 :     Dest = reinterpret_cast<const T *>(Buffer.data());
      52             :     return Error::success();
      53             :   }
      54             : 
      55             :   template <typename T>
      56         199 :   Error readArray(ArrayRef<T> &Array, uint32_t NumElements) {
      57         199 :     ArrayRef<uint8_t> Bytes;
      58         199 :     if (NumElements == 0) {
      59          16 :       Array = ArrayRef<T>();
      60             :       return Error::success();
      61             :     }
      62             : 
      63         183 :     if (NumElements > UINT32_MAX / sizeof(T))
      64           0 :       return make_error<MsfError>(msf_error_code::insufficient_buffer);
      65             : 
      66         549 :     if (auto EC = readBytes(Bytes, NumElements * sizeof(T)))
      67           0 :       return EC;
      68         183 :     Array = ArrayRef<T>(reinterpret_cast<const T *>(Bytes.data()), NumElements);
      69             :     return Error::success();
      70             :   }
      71             : 
      72             :   template <typename T, typename U>
      73         366 :   Error readArray(VarStreamArray<T, U> &Array, uint32_t Size) {
      74         366 :     ReadableStreamRef S;
      75        1098 :     if (auto EC = readStreamRef(S, Size))
      76           0 :       return EC;
      77         366 :     Array = VarStreamArray<T, U>(S, Array.getExtractor());
      78             :     return Error::success();
      79             :   }
      80             : 
      81             :   template <typename T>
      82          55 :   Error readArray(FixedStreamArray<T> &Array, uint32_t NumItems) {
      83          55 :     if (NumItems == 0) {
      84           4 :       Array = FixedStreamArray<T>();
      85             :       return Error::success();
      86             :     }
      87          51 :     uint32_t Length = NumItems * sizeof(T);
      88          51 :     if (Length / sizeof(T) != NumItems)
      89           0 :       return make_error<MsfError>(msf_error_code::invalid_format);
      90          51 :     if (Offset + Length > Stream.getLength())
      91           0 :       return make_error<MsfError>(msf_error_code::insufficient_buffer);
      92          51 :     ReadableStreamRef View = Stream.slice(Offset, Length);
      93          51 :     Array = FixedStreamArray<T>(View);
      94          51 :     Offset += Length;
      95             :     return Error::success();
      96             :   }
      97             : 
      98        4819 :   void setOffset(uint32_t Off) { Offset = Off; }
      99             :   uint32_t getOffset() const { return Offset; }
     100         802 :   uint32_t getLength() const { return Stream.getLength(); }
     101         457 :   uint32_t bytesRemaining() const { return getLength() - getOffset(); }
     102             : 
     103             : private:
     104             :   ReadableStreamRef Stream;
     105             :   uint32_t Offset;
     106             : };
     107             : } // namespace msf
     108             : } // namespace llvm
     109             : 
     110             : #endif // LLVM_DEBUGINFO_MSF_STREAMREADER_H