[pdb] Handle stream index errors better.

Reviewed By: ruiu
Differential Revision: http://reviews.llvm.org/D21128

llvm-svn: 272172

1 files changed, 26 insertions, 23 deletions

diff --git a/llvm/lib/DebugInfo/PDB/Raw/DbiStream.cpp b/llvm/lib/DebugInfo/PDB/Raw/DbiStream.cpp
index 90bc2a2e556..ae3faa700c1 100644
--- a/llvm/lib/DebugInfo/PDB/Raw/DbiStream.cpp
+++ b/llvm/lib/DebugInfo/PDB/Raw/DbiStream.cpp
@@ -93,19 +93,17 @@ Error loadSectionContribs(FixedStreamArray<ContribType> &Output,
   return Error::success();
 }
 
-DbiStream::DbiStream(PDBFile &File)
-    : Pdb(File),
-      Stream(llvm::make_unique<IndexedStreamData>(StreamDBI, File), File),
-      Header(nullptr) {
+DbiStream::DbiStream(PDBFile &File, std::unique_ptr<MappedBlockStream> Stream)
+    : Pdb(File), Stream(std::move(Stream)), Header(nullptr) {
   static_assert(sizeof(HeaderInfo) == 64, "Invalid HeaderInfo size!");
 }
 
 DbiStream::~DbiStream() {}
 
 Error DbiStream::reload() {
-  StreamReader Reader(Stream);
+  StreamReader Reader(*Stream);
 
-  if (Stream.getLength() < sizeof(HeaderInfo))
+  if (Stream->getLength() < sizeof(HeaderInfo))
     return make_error<RawError>(raw_error_code::corrupt_file,
                                 "DBI Stream does not contain a header.");
   if (auto EC = Reader.readObject(Header))
@@ -123,15 +121,15 @@ Error DbiStream::reload() {
     return make_error<RawError>(raw_error_code::feature_unsupported,
                                 "Unsupported DBI version.");
 
-  auto InfoStream = Pdb.getPDBInfoStream();
-  if (auto EC = InfoStream.takeError())
-    return EC;
+  auto IS = Pdb.getPDBInfoStream();
+  if (!IS)
+    return IS.takeError();
 
-  if (Header->Age != InfoStream.get().getAge())
+  if (Header->Age != IS->getAge())
     return make_error<RawError>(raw_error_code::corrupt_file,
                                 "DBI Age does not match PDB Age.");
 
-  if (Stream.getLength() !=
+  if (Stream->getLength() !=
       sizeof(HeaderInfo) + Header->ModiSubstreamSize +
           Header->SecContrSubstreamSize + Header->SectionMapSize +
           Header->FileInfoSize + Header->TypeServerSize +
@@ -296,19 +294,22 @@ Error DbiStream::initializeSectionHeadersData() {
   if (StreamNum >= Pdb.getNumStreams())
     return make_error<RawError>(raw_error_code::no_stream);
 
-  SectionHeaderStream.reset(new MappedBlockStream(
-      llvm::make_unique<IndexedStreamData>(StreamNum, Pdb), Pdb));
+  auto SHS = MappedBlockStream::createIndexedStream(StreamNum, Pdb);
+  if (!SHS)
+    return SHS.takeError();
 
-  size_t StreamLen = SectionHeaderStream->getLength();
+  size_t StreamLen = (*SHS)->getLength();
   if (StreamLen % sizeof(object::coff_section))
     return make_error<RawError>(raw_error_code::corrupt_file,
                                 "Corrupted section header stream.");
 
   size_t NumSections = StreamLen / sizeof(object::coff_section);
-  codeview::StreamReader Reader(*SectionHeaderStream);
+  codeview::StreamReader Reader(**SHS);
   if (auto EC = Reader.readArray(SectionHeaders, NumSections))
     return make_error<RawError>(raw_error_code::corrupt_file,
                                 "Could not read a bitmap.");
+
+  SectionHeaderStream = std::move(*SHS);
   return Error::success();
 }
 
@@ -318,19 +319,21 @@ Error DbiStream::initializeFpoRecords() {
   if (StreamNum >= Pdb.getNumStreams())
     return make_error<RawError>(raw_error_code::no_stream);
 
-  FpoStream.reset(new MappedBlockStream(
-      llvm::make_unique<IndexedStreamData>(StreamNum, Pdb), Pdb));
+  auto FS = MappedBlockStream::createIndexedStream(StreamNum, Pdb);
+  if (!FS)
+    return FS.takeError();
 
-  size_t StreamLen = FpoStream->getLength();
+  size_t StreamLen = (*FS)->getLength();
   if (StreamLen % sizeof(object::FpoData))
     return make_error<RawError>(raw_error_code::corrupt_file,
                                 "Corrupted New FPO stream.");
 
   size_t NumRecords = StreamLen / sizeof(object::FpoData);
-  codeview::StreamReader Reader(*FpoStream);
+  codeview::StreamReader Reader(**FS);
   if (auto EC = Reader.readArray(FpoRecords, NumRecords))
     return make_error<RawError>(raw_error_code::corrupt_file,
                                 "Corrupted New FPO stream.");
+  FpoStream = std::move(*FS);
   return Error::success();
 }
 
@@ -418,10 +421,10 @@ Error DbiStream::initializeFileInfo() {
     uint32_t NumFiles = ModFileCountArray[I];
     ModuleInfos[I].SourceFiles.resize(NumFiles);
     for (size_t J = 0; J < NumFiles; ++J, ++NextFileIndex) {
-      if (auto Name = getFileNameForIndex(NextFileIndex))
-        ModuleInfos[I].SourceFiles[J] = Name.get();
-      else
-        return Name.takeError();
+      auto ThisName = getFileNameForIndex(NextFileIndex);
+      if (!ThisName)
+        return ThisName.takeError();
+      ModuleInfos[I].SourceFiles[J] = *ThisName;
     }
   }