5 files changed, 83 insertions, 0 deletions
diff --git a/llvm/lib/Object/Binary.cpp b/llvm/lib/Object/Binary.cpp
index 87b2c1278c0..e1063a64b14 100644
--- a/llvm/lib/Object/Binary.cpp
+++ b/llvm/lib/Object/Binary.cpp
@@ -16,6 +16,7 @@
 #include "llvm/Object/Archive.h"
 #include "llvm/Object/Error.h"
 #include "llvm/Object/MachOUniversal.h"
+#include "llvm/Object/Minidump.h"
 #include "llvm/Object/ObjectFile.h"
 #include "llvm/Object/WindowsResource.h"
 #include "llvm/Support/Error.h"
@@ -81,6 +82,8 @@ Expected<std::unique_ptr<Binary>> object::createBinary(MemoryBufferRef Buffer,
   case file_magic::coff_cl_gl_object:
     // Unrecognized object file format.
     return errorCodeToError(object_error::invalid_file_type);
+  case file_magic::minidump:
+    return MinidumpFile::create(Buffer);
   }
   llvm_unreachable("Unexpected Binary File Type");
 }
diff --git a/llvm/lib/Object/CMakeLists.txt b/llvm/lib/Object/CMakeLists.txt
index fd5e7707c54..a0ac0046c0b 100644
--- a/llvm/lib/Object/CMakeLists.txt
+++ b/llvm/lib/Object/CMakeLists.txt
@@ -13,6 +13,7 @@ add_llvm_library(LLVMObject
   IRSymtab.cpp
   MachOObjectFile.cpp
   MachOUniversal.cpp
+  Minidump.cpp
   ModuleSymbolTable.cpp
   Object.cpp
   ObjectFile.cpp
diff --git a/llvm/lib/Object/Minidump.cpp b/llvm/lib/Object/Minidump.cpp
new file mode 100644
index 00000000000..d0d49b4e8d3
--- /dev/null
+++ b/llvm/lib/Object/Minidump.cpp
@@ -0,0 +1,77 @@
+//===- Minidump.cpp - Minidump object file implementation -----------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Object/Minidump.h"
+#include "llvm/Object/Error.h"
+
+using namespace llvm;
+using namespace llvm::object;
+using namespace llvm::minidump;
+
+Optional<ArrayRef<uint8_t>>
+MinidumpFile::getRawStream(minidump::StreamType Type) const {
+  auto It = StreamMap.find(Type);
+  if (It != StreamMap.end())
+    return getRawStream(Streams[It->second]);
+  return None;
+}
+
+Expected<ArrayRef<uint8_t>>
+MinidumpFile::getDataSlice(ArrayRef<uint8_t> Data, size_t Offset, size_t Size) {
+  // Check for overflow.
+  if (Offset + Size < Offset || Offset + Size < Size ||
+      Offset + Size > Data.size())
+    return createEOFError();
+  return Data.slice(Offset, Size);
+}
+
+Expected<std::unique_ptr<MinidumpFile>>
+MinidumpFile::create(MemoryBufferRef Source) {
+  ArrayRef<uint8_t> Data = arrayRefFromStringRef(Source.getBuffer());
+  auto ExpectedHeader = getDataSliceAs<minidump::Header>(Data, 0, 1);
+  if (!ExpectedHeader)
+    return ExpectedHeader.takeError();
+
+  const minidump::Header &Hdr = (*ExpectedHeader)[0];
+  if (Hdr.Signature != Header::MagicSignature)
+    return createError("Invalid signature");
+  if ((Hdr.Version & 0xffff) != Header::MagicVersion)
+    return createError("Invalid version");
+
+  auto ExpectedStreams = getDataSliceAs<Directory>(Data, Hdr.StreamDirectoryRVA,
+                                                   Hdr.NumberOfStreams);
+  if (!ExpectedStreams)
+    return ExpectedStreams.takeError();
+
+  DenseMap<StreamType, std::size_t> StreamMap;
+  for (const auto &Stream : llvm::enumerate(*ExpectedStreams)) {
+    StreamType Type = Stream.value().Type;
+    const LocationDescriptor &Loc = Stream.value().Location;
+
+    auto ExpectedStream = getDataSlice(Data, Loc.RVA, Loc.DataSize);
+    if (!ExpectedStream)
+      return ExpectedStream.takeError();
+
+    if (Type == StreamType::Unused && Loc.DataSize == 0) {
+      // Ignore dummy streams. This is technically ill-formed, but a number of
+      // existing minidumps seem to contain such streams.
+      continue;
+    }
+
+    if (Type == DenseMapInfo<StreamType>::getEmptyKey() ||
+        Type == DenseMapInfo<StreamType>::getTombstoneKey())
+      return createError("Cannot handle one of the minidump streams");
+
+    // Update the directory map, checking for duplicate stream types.
+    if (!StreamMap.try_emplace(Type, Stream.index()).second)
+      return createError("Duplicate stream type");
+  }
+
+  return std::unique_ptr<MinidumpFile>(
+      new MinidumpFile(Source, Hdr, *ExpectedStreams, std::move(StreamMap)));
+}
diff --git a/llvm/lib/Object/ObjectFile.cpp b/llvm/lib/Object/ObjectFile.cpp
index 441ef54bd84..cf095db8e8c 100644
--- a/llvm/lib/Object/ObjectFile.cpp
+++ b/llvm/lib/Object/ObjectFile.cpp
@@ -127,6 +127,7 @@ ObjectFile::createObjectFile(MemoryBufferRef Object, file_magic Type) {
   case file_magic::macho_universal_binary:
   case file_magic::windows_resource:
   case file_magic::pdb:
+  case file_magic::minidump:
     return errorCodeToError(object_error::invalid_file_type);
   case file_magic::elf:
   case file_magic::elf_relocatable:
diff --git a/llvm/lib/Object/SymbolicFile.cpp b/llvm/lib/Object/SymbolicFile.cpp
index 8ee82567710..675f2091518 100644
--- a/llvm/lib/Object/SymbolicFile.cpp
+++ b/llvm/lib/Object/SymbolicFile.cpp
@@ -52,6 +52,7 @@ SymbolicFile::createSymbolicFile(MemoryBufferRef Object, file_magic Type,
   case file_magic::macho_universal_binary:
   case file_magic::windows_resource:
   case file_magic::pdb:
+  case file_magic::minidump:
     return errorCodeToError(object_error::invalid_file_type);
   case file_magic::elf:
   case file_magic::elf_executable: