Support zero-length mapped files
Bug: http://b/119818070 "app crashes when reading asset of zero length"
Add support for zero-length mappings for the Windows code path as well.
Test: ran libbase_test on Windows under wine.
Change-Id: Iccb65fa800c636444100c9369f41e36d24a53a99
diff --git a/base/mapped_file.cpp b/base/mapped_file.cpp
index faa845d..7c65dc3 100644
--- a/base/mapped_file.cpp
+++ b/base/mapped_file.cpp
@@ -41,7 +41,14 @@
HANDLE handle =
CreateFileMapping(reinterpret_cast<HANDLE>(_get_osfhandle(fd)), nullptr,
(prot & PROT_WRITE) ? PAGE_READWRITE : PAGE_READONLY, 0, 0, nullptr);
- if (handle == nullptr) return nullptr;
+ if (handle == nullptr) {
+ // http://b/119818070 "app crashes when reading asset of zero length".
+ // Return a MappedFile that's only valid for reading the size.
+ if (length == 0) {
+ return std::unique_ptr<MappedFile>(new MappedFile{nullptr, 0, 0, nullptr});
+ }
+ return nullptr;
+ }
void* base = MapViewOfFile(handle, (prot & PROT_WRITE) ? FILE_MAP_ALL_ACCESS : FILE_MAP_READ, 0,
file_offset, file_length);
if (base == nullptr) {