port: ProcessCRC verbatim (module introspection adapted) + XTrap mapped

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/platform/UserInterface/ProcessCRC.cpp

@@ -1,23 +1,87 @@
-// Platform skeleton for UserInterface/ProcessCRC.h (40250 UserInterface/ProcessCRC.cpp), generated by platform_stub.py.
-// Every MT_PLATFORM_STUB() body is unimplemented: replace it with the platform implementation.
+// 40250 UserInterface/ProcessCRC.cpp, verbatim except the Win32 process introspection (see PORT below).
+// GetExeCRC is declared in ProcessCRC.h but only __GetExeCRC is defined in 40250.
 #include "UserInterface/StdAfx.h"
 #include "UserInterface/ProcessCRC.h"
 
-#include "../PlatformStub.h"
+static BYTE abCRCMagicCube[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
+static BYTE abCRCXorTable[8] = { 102, 30, 188, 44, 39, 201, 43, 5 };
+static BYTE bMagicCubeIdx = 0;
 
-auto GetExeCRC(DWORD &, DWORD &) -> bool
+const char * stristr(const char * big, const char * little)
 {
-	MT_PLATFORM_STUB();
-	return mt_platform_stub_return<bool>();
+	const char * t = big;
+	size_t len = strlen(little) - 1;
+
+	for (t = big; *t; ++t)
+		if (!_strnicmp(t, little, len))
+			return t;
+
+	return NULL;
 }
 
-auto BuildProcessCRC() -> void
+// PORT: 40250 walks a Toolhelp32 module snapshot for the module whose path contains the executable name and
+// returns its path and load address. The platform has no module snapshot, so the executable is never found:
+// the path in which 40250 gives up the same way (then ProcCRC = 0).
+bool GetProcessInformation(std::string & exeFileName, LPCVOID * ppvAddress)
 {
-	MT_PLATFORM_STUB();
+	return false;
 }
 
-auto GetProcessCRCMagicCubePiece() -> BYTE
+// PORT: 40250 ReadProcessMemory's the first 1 MB of the module image and CRCs it (a partial copy counts).
+// Unreachable here (GetProcessInformation never finds the module); returns 0 as 40250 does on a failed read.
+DWORD GetProcessMemoryCRC(LPCVOID c_pvBaseAddress)
 {
-	MT_PLATFORM_STUB();
-	return mt_platform_stub_return<BYTE>();
+	return 0;
+}
+
+bool __GetExeCRC(DWORD & r_dwProcCRC, DWORD & r_dwFileCRC)
+{
+	std::string exeFileName;
+	LPCVOID c_pvBaseAddress;
+
+	GetExcutedFileName(exeFileName);
+
+	if (GetProcessInformation(exeFileName, &c_pvBaseAddress))
+		r_dwProcCRC = GetProcessMemoryCRC(c_pvBaseAddress);
+	else
+		r_dwProcCRC = 0;
+
+	r_dwFileCRC = GetFileCRC32(exeFileName.c_str());
+	return true;
+}
+
+void BuildProcessCRC()
+{
+	if (LocaleService_IsHONGKONG() || LocaleService_IsTAIWAN())
+	{
+		memset(abCRCMagicCube, 0, sizeof(abCRCMagicCube));
+		bMagicCubeIdx = 0;
+		return;
+	}
+	
+	DWORD dwProcCRC, dwFileCRC;
+
+	if (__GetExeCRC(dwProcCRC, dwFileCRC))
+	{
+		abCRCMagicCube[0] = BYTE(dwProcCRC & 0x000000ff);
+		abCRCMagicCube[1] = BYTE(dwFileCRC & 0x000000ff);
+		abCRCMagicCube[2] = BYTE( (dwProcCRC & 0x0000ff00) >> 8 );
+		abCRCMagicCube[3] = BYTE( (dwFileCRC & 0x0000ff00) >> 8 );
+		abCRCMagicCube[4] = BYTE( (dwProcCRC & 0x00ff0000) >> 16 );
+		abCRCMagicCube[5] = BYTE( (dwFileCRC & 0x00ff0000) >> 16 );
+		abCRCMagicCube[6] = BYTE( (dwProcCRC & 0xff000000) >> 24 );
+		abCRCMagicCube[7] = BYTE( (dwFileCRC & 0xff000000) >> 24 );
+
+		bMagicCubeIdx = 0;
+	}
+}
+
+BYTE GetProcessCRCMagicCubePiece()
+{
+	BYTE bPiece = BYTE(abCRCMagicCube[bMagicCubeIdx] ^ abCRCXorTable[bMagicCubeIdx]);
+
+	if (!(++bMagicCubeIdx & 7))
+		bMagicCubeIdx = 0;
+
+	return bPiece;
 }

src/port/CMakeLists.txt

@@ -199,6 +199,10 @@ if(BUILD_TESTING AND CMAKE_SYSTEM_NAME STREQUAL CMAKE_HOST_SYSTEM_NAME)
     add_test(NAME port.text_bar COMMAND $<TARGET_FILE:port_text_bar_test>)
     set_tests_properties(port.text_bar PROPERTIES SKIP_RETURN_CODE 77)
 
+    add_executable(port_process_crc_test ${PROJECT_SOURCE_DIR}/tests/port/port_process_crc_test.cpp)
+    target_link_libraries(port_process_crc_test PRIVATE port_platform)
+    add_test(NAME port.process_crc COMMAND $<TARGET_FILE:port_process_crc_test>)
+
     # MilesLib: the 40250 sound managers over the Miles emulation (platform/MilesLib/MilesAil.cpp).
     add_executable(port_miles_test ${PROJECT_SOURCE_DIR}/tests/port/port_miles_test.cpp)
     target_link_libraries(port_miles_test PRIVATE port_platform)