- PageSize)) {
- off_t RealMapOffset = Offset & ~(PageSize - 1);
- off_t Delta = Offset - RealMapOffset;
- size_t RealMapSize = MapSize + Delta;
-
- if (const char *Pages = sys::Path::MapInFilePages(FD,
- RealMapSize,
- RealMapOffset)) {
- result.reset(GetNamedBuffer<MemoryBufferMMapFile>(
- StringRef(Pages + Delta, MapSize), Filename, RequiresNullTerminator));
-
- if (RequiresNullTerminator && result->getBufferEnd()[0] != '\0') {
- // There could be a racing issue that resulted in the file being larger
- // than the FileSize passed by the caller. We already have an assertion
- // for this in MemoryBuffer::init() but have a runtime guarantee that
- // the buffer will be null-terminated here, so do a copy that adds a
- // null-terminator.
- result.reset(MemoryBuffer::getMemBufferCopy(result->getBuffer(),
- Filename));
- }
- return error_code::success();
- }
+ PageSize, IsVolatileSize)) {
+ std::error_code EC;
+ std::unique_ptr<MemoryBuffer> Result(
+ new (NamedBufferAlloc(Filename))
+ MemoryBufferMMapFile(RequiresNullTerminator, FD, MapSize, Offset, EC));
+ if (!EC)
+ return std::move(Result);