[memory linux] Properly unlink shared memory

shm_unlink(name) is the proper way to close a shared memory in linux.
Prior to this, xenia was creating and not cleaning up shared memory handle
which would accumulate in /dev/shm. shm_unlink is the proper way of doing
this.
Add filename to CloseFileMappingHandle signature.
Add simple test to open and close.

src/xenia/base/memory.h

@@ -99,7 +99,7 @@ typedef void* FileMappingHandle;
 
 FileMappingHandle CreateFileMappingHandle(std::wstring path, size_t length,
                                           PageAccess access, bool commit);
-void CloseFileMappingHandle(FileMappingHandle handle);
+void CloseFileMappingHandle(FileMappingHandle handle, std::wstring path);
 void* MapFileView(FileMappingHandle handle, void* base_address, size_t length,
                   PageAccess access, size_t file_offset);
 bool UnmapFileView(FileMappingHandle handle, void* base_address, size_t length);

src/xenia/base/memory_posix.cc

@@ -96,8 +96,9 @@ FileMappingHandle CreateFileMappingHandle(std::wstring path, size_t length,
   return ret <= 0 ? nullptr : reinterpret_cast<FileMappingHandle>(ret);
 }
 
-void CloseFileMappingHandle(FileMappingHandle handle) {
-  close(static_cast<int>(reinterpret_cast<int64_t>(handle)));
+void CloseFileMappingHandle(FileMappingHandle handle, std::wstring path) {
+  std::string full_path = "/" + xe::to_string(path);
+  shm_unlink(full_path.c_str());
 }
 
 void* MapFileView(FileMappingHandle handle, void* base_address, size_t length,

src/xenia/base/memory_win.cc

@@ -152,7 +152,9 @@ FileMappingHandle CreateFileMappingHandle(std::wstring path, size_t length,
                             static_cast<DWORD>(length), full_path.c_str());
 }
 
-void CloseFileMappingHandle(FileMappingHandle handle) { CloseHandle(handle); }
+void CloseFileMappingHandle(FileMappingHandle handle, std::wstring path) {
+  CloseHandle(handle);
+}
 
 void* MapFileView(FileMappingHandle handle, void* base_address, size_t length,
                   PageAccess access, size_t file_offset) {

src/xenia/base/testing/memory_test.cc

@@ -414,6 +414,13 @@ TEST_CASE("copy_and_swap_16_in_32_unaligned", "Copy and Swap") {
   REQUIRE(true == true);
 }
 
+TEST_CASE("create_and_close_file_mapping", "Virtual Memory Mapping") {
+  auto memory = xe::memory::CreateFileMappingHandle(
+      L"test", 0x100, xe::memory::PageAccess::kReadWrite, false);
+  REQUIRE(memory);
+  xe::memory::CloseFileMappingHandle(memory, L"test");
+}
+
 }  // namespace test
 }  // namespace base
 }  // namespace xe

src/xenia/cpu/backend/x64/x64_code_cache.cc

@@ -42,7 +42,7 @@ X64CodeCache::~X64CodeCache() {
   if (mapping_) {
     xe::memory::UnmapFileView(mapping_, generated_code_base_,
                               kGeneratedCodeSize);
-    xe::memory::CloseFileMappingHandle(mapping_);
+    xe::memory::CloseFileMappingHandle(mapping_, file_name_);
     mapping_ = nullptr;
   }
 }

src/xenia/memory.cc

@@ -112,7 +112,7 @@ Memory::~Memory() {
   // Unmap all views and close mapping.
   if (mapping_) {
     UnmapViews();
-    xe::memory::CloseFileMappingHandle(mapping_);
+    xe::memory::CloseFileMappingHandle(mapping_, file_name_);
     mapping_base_ = nullptr;
     mapping_ = nullptr;
   }