Updated diaghub support to match correct interface.

_msbuild_test.py

@@ -48,12 +48,14 @@
             CSourceFile('etwtrace/_tdhreader.cpp'),
             IncludeFile('etwtrace/_tdhreader.h'),
         ),
-        PydFile(
-            'DiagnosticsHub.InstrumentationCollector',
-            *PYD_OPTS,
-            CSourceFile('etwtrace/_diaghubstub.c'),
-            TargetExt='.dll',
-        ),
+        # This package will be renamed in init_PACKAGE
+        Package('arch',
+            CProject(
+                'DiagnosticsHubStub',
+                *PYD_OPTS,
+                CSourceFile('etwtrace/_diaghubstub.c'),
+            ),
+        )
     ),
     source='src',
 )
@@ -65,3 +67,14 @@ def init_METADATA():
     if sep and re.match(r"\d+(\.\d+)+((a|b|rc)\d+)?$", version):
         # Looks like a version tag
         METADATA["Version"] = version
+
+
+def init_PACKAGE(tag=None):
+    if not tag:
+        return
+    if tag.endswith("-win32"):
+        PACKAGE.find('test/arch').name = 'x86'
+    elif tag.endswith("-win_amd64"):
+        PACKAGE.find('test/arch').name = 'amd64'
+    elif tag.endswith("-win_arm64"):
+        PACKAGE.find('test/arch').name = 'arm64'

src/etwtrace/__init__.py

@@ -101,16 +101,28 @@ def __init__(self):
 
 class DiagnosticsHubTracer(_TracingMixin):
     def __init__(self, stub=False):
+        self._data = None
         if stub:
             from ctypes import PyDLL, py_object
             from pathlib import Path
+            from os import environ
+            from sys import winver
             self._data = []
-            dll = Path(__file__).parent / "test" / "DiagnosticsHub.InstrumentationCollector.dll"
+            root = Path(__file__).parent / "test"
+            if winver.endswith("-32"):
+                dll = root / "x86"
+            elif winver.endswith("-arm64"):
+                dll = root / "arm64"
+            else:
+                dll = root / "amd64"
+            dll = dll / "DiagnosticsHubStub.dll"
             if not dll.is_file():
                 raise RuntimeError("Diagnostics hub stub requires test files")
             self._stub = PyDLL(str(dll))
             self._stub.OnEvent.argtypes = [py_object]
             self._stub.OnEvent(lambda *a: self._on_event(*a))
+            environ["DIAGHUB_INSTR_COLLECTOR_ROOT"] = str(root)
+            environ["DIAGHUB_INSTR_RUNTIME_NAME"] = dll.name
         super().__init__()
         from . import _vsinstrument as mod
         self._module = mod
@@ -121,7 +133,8 @@ def _on_event(self, *args):
 
     def disable(self):
         super().disable()
-        print(*self._data, sep="\n")
+        if self._data:
+            print(*self._data, sep="\n")
 
 
 def enable_if(enable_var, type_var):

src/etwtrace/_diaghubstub.c

@@ -55,6 +55,20 @@ EXPORT void PROBE_IMPL Cap_Define_Script_Function(_In_ void* pFunction, _In_ voi
     }
 }
 
+EXPORT BOOL PROBE_IMPL ChildAttach()
+{
+    if (_on_event) {
+        PyObject *r = PyObject_CallFunction(_on_event, "s", "ChildAttach");
+        if (!r) {
+            PyErr_WriteUnraisable(NULL);
+            return FALSE;
+        } else {
+            Py_DECREF(r);
+        }
+    }
+    return TRUE;
+}
+
 EXPORT void PROBE_IMPL Stub_Write_Mark(_In_ int opcode, _In_z_ LPCWSTR szMark)
 {
     if (_on_event) {

src/etwtrace/_vsinstrument.c

@@ -278,14 +278,52 @@ static int vsinstrument_exec(PyObject *m)
         return -1;
     }
 
-    // We ensure the DLL is loaded already before loading it again, but
-    // use LoadLibraryW to increment the reference count to ensure it does not
-    // get freed on us.
-    if (!GetModuleHandleW(L"DiagnosticsHub.InstrumentationCollector.dll")) {
-        PyErr_SetString(PyExc_RuntimeError, "VS tracing must be launched from Diagnostics Hub");
+#if defined(_M_IX86)
+    const wchar_t * const subpath = L"\\x86\\";
+#elif defined(_M_AMD64)
+    const wchar_t * const subpath = L"\\amd64\\";
+#elif defined(_M_ARM64)
+    const wchar_t * const subpath = L"\\arm64\\";
+#else
+    #error Unsupported architecture
+#endif
+
+    DWORD cchPath = GetEnvironmentVariableW(L"DIAGHUB_INSTR_COLLECTOR_ROOT", NULL, 0);
+    if (!cchPath) {
+        PyErr_SetFromWindowsErr(0);
+        return -1;
+    }
+    DWORD cchName = GetEnvironmentVariableW(L"DIAGHUB_INSTR_RUNTIME_NAME", NULL, 0);
+    if (!cchName) {
+        PyErr_SetFromWindowsErr(0);
+        return -1;
+    }
+    cchPath = cchPath + cchName + (DWORD)wcslen(subpath);
+    wchar_t *path = (wchar_t *)PyMem_Malloc(cchPath * sizeof(wchar_t));
+    if (!path) {
+        PyErr_NoMemory();
+        return -1;
+    }
+
+    DWORD cch = GetEnvironmentVariable(L"DIAGHUB_INSTR_COLLECTOR_ROOT", path, cchPath);
+    if (!cch) {
+        PyErr_SetFromWindowsErr(0);
         return -1;
     }
-    state->hModule = LoadLibraryW(L"DiagnosticsHub.InstrumentationCollector.dll");
+    while (cch > 0 && path[cch - 1] == L'\\') {
+        --cch;
+    }
+    wcscpy_s(&path[cch], cchPath - cch, subpath);
+    cch += (DWORD)wcslen(subpath);
+
+    if (!GetEnvironmentVariable(L"DIAGHUB_INSTR_RUNTIME_NAME", &path[cch], cchPath - cch)) {
+        PyMem_Free(path);
+        PyErr_SetFromWindowsErr(0);
+        return -1;
+    }
+
+    state->hModule = LoadLibraryW(path);
+    PyMem_Free(path);
     if (!state->hModule) {
         PyErr_SetFromWindowsErr(0);
         return -1;
@@ -314,6 +352,17 @@ static int vsinstrument_exec(PyObject *m)
     // Allowed to be absent
     state->WriteMark = (Stub_Write_Mark)GetProcAddress(state->hModule, "Stub_Write_Mark");
 
+    BOOL (*childAttach)() = (BOOL (*)())GetProcAddress(state->hModule, "ChildAttach");
+    if (!childAttach) {
+        PyErr_SetFromWindowsErr(0);
+        return -1;
+    }
+
+    if (!(*childAttach)()) {
+        PyErr_SetString(PyExc_RuntimeError, "Failed to attach to profiler");
+        return -1;
+    }
+
     return 0;
 }
 

tests/test_diaghub.py

@@ -65,10 +65,28 @@ def test_but_do_we_diaghub():
     with subprocess.Popen(
         [sys.executable, "-m", "etwtrace", "--diaghub", "--", SCRIPTS / "no_events.py"],
         cwd=SCRIPTS,
+        env={
+            **os.environ,
+            "DIAGHUB_INSTR_COLLECTOR_ROOT": "",
+            "DIAGHUB_INSTR_RUNTIME_NAME": "",
+        },
     ) as p:
         p.wait()
         assert p.returncode
 
+    # We should succeed, but can't tell what's happened
+    with subprocess.Popen(
+        [sys.executable, "-m", "etwtrace", "--diaghub", "--", SCRIPTS / "no_events.py"],
+        cwd=SCRIPTS,
+        env={
+            **os.environ,
+            "DIAGHUB_INSTR_COLLECTOR_ROOT": str(Path(etwtrace.__file__).parent / "test"),
+            "DIAGHUB_INSTR_RUNTIME_NAME": "DiagnosticsHubStub.dll",
+        },
+    ) as p:
+        p.wait()
+        assert not p.returncode
+
 
 def test_but_do_we_diaghubtest():
     subprocess.check_call(