Use the actual process image instead of module filename to dedup session (#19415)

DHowett · DHowett · commit 96f13a15deed · 2025-10-08T17:53:51.000-05:00
Apparently, `GetModuleFileNameW` returns exactly the path (or prefix, in case of a DLL) passed to `CreateProcess` casing and all. Since we were using it to generate the uniquing hash for Portable and Unpackaged instances, this meant that `C:\Terminal\wt` and `C:\TeRmInAl\wt` were considered different instances. Whoops. Using `QueryFullProcessImageNameW` instead results in canonicalization. Maybe the kernel does it. I don't know. What I do know is that it works more correctly. (`Query...` goes through the kernel, while `GetModule...` goes through the loader. Interesting!) Closes #19253 (cherry picked from commit 9d7ea77) Service-Card-Id: PVTI_lADOAF3p4s4AxadtzgfkTus Service-Version: 1.23
diff --git a/src/cascadia/WindowsTerminal/WindowEmperor.cpp b/src/cascadia/WindowsTerminal/WindowEmperor.cpp
@@ -315,7 +315,7 @@ void WindowEmperor::HandleCommandlineArgs(int nCmdShow)
     }
     if (!IsPackaged())
     {
-        const auto path = wil::GetModuleFileNameW<std::wstring>(nullptr);
+        const auto path = wil::QueryFullProcessImageNameW<std::wstring>();
         const auto hash = til::hash(path);
 #ifdef _WIN64
         fmt::format_to(std::back_inserter(windowClassName), FMT_COMPILE(L" {:016x}"), hash);

Original file line number	Diff line number	Diff line change
`@@ -315,7 +315,7 @@ void WindowEmperor::HandleCommandlineArgs(int nCmdShow)`
`315`	`315`	`}`
`316`	`316`	`if (!IsPackaged())`
`317`	`317`	`{`
`318`		`- const auto path = wil::GetModuleFileNameW<std::wstring>(nullptr);`
	`318`	`+ const auto path = wil::QueryFullProcessImageNameW<std::wstring>();`
`319`	`319`	`const auto hash = til::hash(path);`
`320`	`320`	`#ifdef _WIN64`
`321`	`321`	`fmt::format_to(std::back_inserter(windowClassName), FMT_COMPILE(L" {:016x}"), hash);`