1 //===- StreamReader.cpp - Reads bytes and objects from a stream -----------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 #include "llvm/DebugInfo/CodeView/StreamReader.h"
12 #include "llvm/DebugInfo/CodeView/CodeViewError.h"
13 #include "llvm/DebugInfo/CodeView/StreamRef.h"
16 using namespace llvm::codeview;
18 StreamReader::StreamReader(StreamRef S) : Stream(S), Offset(0) {}
20 Error StreamReader::readLongestContiguousChunk(ArrayRef<uint8_t> &Buffer) {
21 if (auto EC = Stream.readLongestContiguousChunk(Offset, Buffer))
23 Offset += Buffer.size();
24 return Error::success();
27 Error StreamReader::readBytes(ArrayRef<uint8_t> &Buffer, uint32_t Size) {
28 if (auto EC = Stream.readBytes(Offset, Size, Buffer))
31 return Error::success();
34 Error StreamReader::readInteger(uint16_t &Dest) {
35 const support::ulittle16_t *P;
36 if (auto EC = readObject(P))
39 return Error::success();
42 Error StreamReader::readInteger(uint32_t &Dest) {
43 const support::ulittle32_t *P;
44 if (auto EC = readObject(P))
47 return Error::success();
50 Error StreamReader::readZeroString(StringRef &Dest) {
52 // First compute the length of the string by reading 1 byte at a time.
53 uint32_t OriginalOffset = getOffset();
56 if (auto EC = readObject(C))
61 // Now go back and request a reference for that many bytes.
62 uint32_t NewOffset = getOffset();
63 setOffset(OriginalOffset);
65 ArrayRef<uint8_t> Data;
66 if (auto EC = readBytes(Data, Length))
68 Dest = StringRef(reinterpret_cast<const char *>(Data.begin()), Data.size());
70 // Now set the offset back to where it was after we calculated the length.
72 return Error::success();
75 Error StreamReader::readFixedString(StringRef &Dest, uint32_t Length) {
76 ArrayRef<uint8_t> Bytes;
77 if (auto EC = readBytes(Bytes, Length))
79 Dest = StringRef(reinterpret_cast<const char *>(Bytes.begin()), Bytes.size());
80 return Error::success();
83 Error StreamReader::readStreamRef(StreamRef &Ref) {
84 return readStreamRef(Ref, bytesRemaining());
87 Error StreamReader::readStreamRef(StreamRef &Ref, uint32_t Length) {
88 if (bytesRemaining() < Length)
89 return make_error<CodeViewError>(cv_error_code::insufficient_buffer);
90 Ref = Stream.slice(Offset, Length);
92 return Error::success();