[llvm-pdbutil] Add the ability to dump raw bytes from the file.

Normally we can only make sense of the content of a PDB in terms
of streams and blocks, but in some cases it may be useful to dump
bytes at a specific absolute file offset.  For example, if you
know that some interesting data is at a particular location and
you want to see some surrounding data.

llvm-svn: 306146

1 files changed, 31 insertions, 0 deletions

diff --git a/llvm/tools/llvm-pdbutil/BytesOutputStyle.cpp b/llvm/tools/llvm-pdbutil/BytesOutputStyle.cpp
index 123c55d2072..9761987f076 100644
--- a/llvm/tools/llvm-pdbutil/BytesOutputStyle.cpp
+++ b/llvm/tools/llvm-pdbutil/BytesOutputStyle.cpp
@@ -96,6 +96,22 @@ Error BytesOutputStyle::dump() {
     P.NewLine();
   }
 
+  if (opts::bytes::DumpByteRange.hasValue()) {
+    auto &R = *opts::bytes::DumpByteRange;
+    uint32_t Max = R.Max.getValueOr(File.getFileSize());
+
+    if (Max < R.Min)
+      return make_error<StringError>("Invalid byte range specified.  Max < Min",
+                                     inconvertibleErrorCode());
+    if (Max >= File.getFileSize())
+      return make_error<StringError>(
+          "Invalid byte range specified.  Requested byte larger than file size",
+          inconvertibleErrorCode());
+
+    dumpByteRanges(R.Min, Max);
+    P.NewLine();
+  }
+
   if (!opts::bytes::DumpStreamData.empty()) {
     dumpStreamBytes();
     P.NewLine();
@@ -122,6 +138,21 @@ void BytesOutputStyle::dumpBlockRanges(uint32_t Min, uint32_t Max) {
   }
 }
 
+void BytesOutputStyle::dumpByteRanges(uint32_t Min, uint32_t Max) {
+  printHeader(P, "MSF Bytes");
+
+  AutoIndent Indent(P);
+
+  BinaryStreamReader Reader(File.getMsfBuffer());
+  ArrayRef<uint8_t> Data;
+  consumeError(Reader.skip(Min));
+  uint32_t Size = Max - Min + 1;
+  auto EC = Reader.readBytes(Data, Size);
+  assert(!EC);
+  consumeError(std::move(EC));
+  P.formatBinary("Bytes", Data, Min);
+}
+
 void BytesOutputStyle::dumpStreamBytes() {
   if (StreamPurposes.empty())
     discoverStreamPurposes(File, StreamPurposes);