[msf] Create LLVMDebugInfoMsf
This provides a better layering of responsibilities among different
aspects of PDB writing code. Some of the MSF related code was
contained in CodeView, and some was in PDB prior to this. Further,
we were often saying PDB when we meant MSF, and the two are
actually independent of each other since in theory you can have
other types of data besides PDB data in an MSF. So, this patch
separates the MSF specific code into its own library, with no
dependencies on anything else, and DebugInfoCodeView and
DebugInfoPDB take dependencies on DebugInfoMsf.
llvm-svn: 276458
diff --git a/llvm/lib/DebugInfo/Msf/StreamReader.cpp b/llvm/lib/DebugInfo/Msf/StreamReader.cpp
new file mode 100644
index 0000000..a2f0f49
--- /dev/null
+++ b/llvm/lib/DebugInfo/Msf/StreamReader.cpp
@@ -0,0 +1,93 @@
+//===- StreamReader.cpp - Reads bytes and objects from a stream -----------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/DebugInfo/Msf/StreamReader.h"
+
+#include "llvm/DebugInfo/Msf/MsfError.h"
+#include "llvm/DebugInfo/Msf/StreamRef.h"
+
+using namespace llvm;
+using namespace llvm::msf;
+
+StreamReader::StreamReader(StreamRef S) : Stream(S), Offset(0) {}
+
+Error StreamReader::readLongestContiguousChunk(ArrayRef<uint8_t> &Buffer) {
+ if (auto EC = Stream.readLongestContiguousChunk(Offset, Buffer))
+ return EC;
+ Offset += Buffer.size();
+ return Error::success();
+}
+
+Error StreamReader::readBytes(ArrayRef<uint8_t> &Buffer, uint32_t Size) {
+ if (auto EC = Stream.readBytes(Offset, Size, Buffer))
+ return EC;
+ Offset += Size;
+ return Error::success();
+}
+
+Error StreamReader::readInteger(uint16_t &Dest) {
+ const support::ulittle16_t *P;
+ if (auto EC = readObject(P))
+ return EC;
+ Dest = *P;
+ return Error::success();
+}
+
+Error StreamReader::readInteger(uint32_t &Dest) {
+ const support::ulittle32_t *P;
+ if (auto EC = readObject(P))
+ return EC;
+ Dest = *P;
+ return Error::success();
+}
+
+Error StreamReader::readZeroString(StringRef &Dest) {
+ uint32_t Length = 0;
+ // First compute the length of the string by reading 1 byte at a time.
+ uint32_t OriginalOffset = getOffset();
+ const char *C;
+ do {
+ if (auto EC = readObject(C))
+ return EC;
+ if (*C != '\0')
+ ++Length;
+ } while (*C != '\0');
+ // Now go back and request a reference for that many bytes.
+ uint32_t NewOffset = getOffset();
+ setOffset(OriginalOffset);
+
+ ArrayRef<uint8_t> Data;
+ if (auto EC = readBytes(Data, Length))
+ return EC;
+ Dest = StringRef(reinterpret_cast<const char *>(Data.begin()), Data.size());
+
+ // Now set the offset back to where it was after we calculated the length.
+ setOffset(NewOffset);
+ return Error::success();
+}
+
+Error StreamReader::readFixedString(StringRef &Dest, uint32_t Length) {
+ ArrayRef<uint8_t> Bytes;
+ if (auto EC = readBytes(Bytes, Length))
+ return EC;
+ Dest = StringRef(reinterpret_cast<const char *>(Bytes.begin()), Bytes.size());
+ return Error::success();
+}
+
+Error StreamReader::readStreamRef(StreamRef &Ref) {
+ return readStreamRef(Ref, bytesRemaining());
+}
+
+Error StreamReader::readStreamRef(StreamRef &Ref, uint32_t Length) {
+ if (bytesRemaining() < Length)
+ return make_error<MsfError>(msf_error_code::insufficient_buffer);
+ Ref = Stream.slice(Offset, Length);
+ Offset += Length;
+ return Error::success();
+}