[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

@@ -101,7 +101,8 @@ typedef void* FileMappingHandle;
 FileMappingHandle CreateFileMappingHandle(const std::filesystem::path& path,
                                           size_t length, PageAccess access,
                                           bool commit);
-void CloseFileMappingHandle(FileMappingHandle handle);
+void CloseFileMappingHandle(FileMappingHandle handle,
+                            const std::filesystem::path& 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

@@ -97,8 +97,10 @@ FileMappingHandle CreateFileMappingHandle(const std::filesystem::path& path,
   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,
+                            const std::filesystem::path& path) {
+  auto full_path = "/" / path;
+  shm_unlink(full_path.c_str());
 }
 
 void* MapFileView(FileMappingHandle handle, void* base_address, size_t length,

src/xenia/base/memory_win.cc

@@ -153,7 +153,10 @@ FileMappingHandle CreateFileMappingHandle(const std::filesystem::path& path,
                             static_cast<DWORD>(length), full_path.c_str());
 }
 
-void CloseFileMappingHandle(FileMappingHandle handle) { CloseHandle(handle); }
+void CloseFileMappingHandle(FileMappingHandle handle,
+                            const std::filesystem::path& 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

@@ -422,7 +422,7 @@ TEST_CASE("create_and_close_file_mapping", "Virtual Memory Mapping") {
   auto memory = xe::memory::CreateFileMappingHandle(
       path, 0x100, xe::memory::PageAccess::kReadWrite, true);
   REQUIRE(memory);
-  xe::memory::CloseFileMappingHandle(memory);
+  xe::memory::CloseFileMappingHandle(memory, path);
 }
 
 TEST_CASE("map_view", "Virtual Memory Mapping") {
@@ -439,7 +439,7 @@ TEST_CASE("map_view", "Virtual Memory Mapping") {
   REQUIRE(reinterpret_cast<uintptr_t>(view) == address);
 
   xe::memory::UnmapFileView(memory, reinterpret_cast<void*>(address), length);
-  xe::memory::CloseFileMappingHandle(memory);
+  xe::memory::CloseFileMappingHandle(memory, path);
 }
 
 TEST_CASE("read_write_view", "Virtual Memory Mapping") {
@@ -466,7 +466,7 @@ TEST_CASE("read_write_view", "Virtual Memory Mapping") {
   }
 
   xe::memory::UnmapFileView(memory, reinterpret_cast<void*>(address), length);
-  xe::memory::CloseFileMappingHandle(memory);
+  xe::memory::CloseFileMappingHandle(memory, path);
 }
 
 }  // namespace test

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

@@ -43,7 +43,7 @@ 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

@@ -115,7 +115,7 @@ 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;
   }