Imported Upstream version 6.10.0.49

Former-commit-id: 1d6753294b2993e1fbf92de9366bb9544db4189b

external/llvm-project/lldb/source/Utility/DataBufferLLVM.cpp

@@ -0,0 +1,68 @@
+//===--- DataBufferLLVM.cpp -------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "lldb/Utility/DataBufferLLVM.h"
+
+#include "llvm/ADT/Twine.h"
+#include "llvm/Support/FileSystem.h"
+#include "llvm/Support/MemoryBuffer.h"
+
+#include <assert.h>    // for assert
+#include <type_traits> // for move
+
+using namespace lldb_private;
+
+DataBufferLLVM::DataBufferLLVM(
+    std::unique_ptr<llvm::WritableMemoryBuffer> MemBuffer)
+    : Buffer(std::move(MemBuffer)) {
+  assert(Buffer != nullptr &&
+         "Cannot construct a DataBufferLLVM with a null buffer");
+}
+
+DataBufferLLVM::~DataBufferLLVM() {}
+
+std::shared_ptr<DataBufferLLVM>
+DataBufferLLVM::CreateSliceFromPath(const llvm::Twine &Path, uint64_t Size,
+                                    uint64_t Offset) {
+  // If the file resides non-locally, pass the volatile flag so that we don't
+  // mmap it.
+  bool IsVolatile = !llvm::sys::fs::is_local(Path);
+
+  auto Buffer =
+      llvm::WritableMemoryBuffer::getFileSlice(Path, Size, Offset, IsVolatile);
+  if (!Buffer)
+    return nullptr;
+  return std::shared_ptr<DataBufferLLVM>(
+      new DataBufferLLVM(std::move(*Buffer)));
+}
+
+std::shared_ptr<DataBufferLLVM>
+DataBufferLLVM::CreateFromPath(const llvm::Twine &Path) {
+  // If the file resides non-locally, pass the volatile flag so that we don't
+  // mmap it.
+  bool IsVolatile = !llvm::sys::fs::is_local(Path);
+
+  auto Buffer = llvm::WritableMemoryBuffer::getFile(Path, -1, IsVolatile);
+  if (!Buffer)
+    return nullptr;
+  return std::shared_ptr<DataBufferLLVM>(
+      new DataBufferLLVM(std::move(*Buffer)));
+}
+
+uint8_t *DataBufferLLVM::GetBytes() {
+  return reinterpret_cast<uint8_t *>(Buffer->getBufferStart());
+}
+
+const uint8_t *DataBufferLLVM::GetBytes() const {
+  return reinterpret_cast<const uint8_t *>(Buffer->getBufferStart());
+}
+
+lldb::offset_t DataBufferLLVM::GetByteSize() const {
+  return Buffer->getBufferSize();
+}