add logic to support windows XP

psutil/_psutil_windows.c

@@ -763,22 +763,39 @@ static PyObject *
 psutil_proc_exe(PyObject *self, PyObject *args) {
     long pid;
     HANDLE hProcess;
-    PDWORD size = MAX_PATH;
     wchar_t exe[MAX_PATH];
+#if (_WIN32_WINNT >= 0x0600)  // >= Vista
+    PDWORD size = MAX_PATH;
+#endif
 
     if (! PyArg_ParseTuple(args, "l", &pid))
         return NULL;
     hProcess = psutil_handle_from_pid(pid, PROCESS_QUERY_LIMITED_INFORMATION);
     if (NULL == hProcess)
         return NULL;
-    // before this was using GetProcessImageFileNameW see:
+
+    // Here we differentiate between XP and Vista+ because
+    // QueryFullProcessImageNameW is better than GetProcessImageFileNameW
+    // (avoid using QueryDosDevice on the returned path), see:
     // https://github.com/giampaolo/psutil/issues/1394
+#if (_WIN32_WINNT >= 0x0600)  // Windows >= Vista
     memset(exe, 0, MAX_PATH);
     if (QueryFullProcessImageNameW(hProcess, 0, exe, &size) == 0) {
         PyErr_SetFromWindowsErr(0);
         CloseHandle(hProcess);
         return NULL;
     }
+#else  // Windows XP
+    if (GetProcessImageFileNameW(hProcess, exe, MAX_PATH) == 0) {
+        // see: https://github.com/giampaolo/psutil/issues/1394
+        if (GetLastError() == 0) {
+            PyErr_SetFromWindowsErr(ERROR_ACCESS_DENIED);
+        else
+            PyErr_SetFromWindowsErr(0);
+        CloseHandle(hProcess);
+        return NULL;
+    }
+#endif
     CloseHandle(hProcess);
     return PyUnicode_FromWideChar(exe, wcslen(exe));
 }

psutil/_pswindows.py

@@ -147,6 +147,28 @@ class Priority(enum.IntEnum):
 AccessDenied = None
 TimeoutExpired = None
 
+# More values at: https://stackoverflow.com/a/20804735/376587
+WIN_10 = (10, 0)
+WIN_8 = (6, 2)
+WIN_7 = (6, 1)
+WIN_SERVER_2008 = (6, 0)
+WIN_VISTA = (6, 0)
+WIN_SERVER_2003 = (5, 2)
+WIN_XP = (5, 1)
+
+
+@lru_cache()
+def get_winver():
+    """Usage:
+    >>> if get_winver() <= WIN_VISTA:
+    ...      ...
+    """
+    wv = sys.getwindowsversion()
+    return (wv.major, wv.minor)
+
+
+IS_WIN_XP = get_winver() < WIN_VISTA
+
 
 # =====================================================================
 # --- named tuples
@@ -694,10 +716,18 @@ def name(self):
 
     @wrap_exceptions
     def exe(self):
-        exe = cext.proc_exe(self.pid)
-        if not PY3:
-            exe = py2_strencode(exe)
-        return exe
+        # Dual implementation, see:
+        # https://github.com/giampaolo/psutil/pull/1413
+        if not IS_WIN_XP:
+            exe = cext.proc_exe(self.pid)
+        else:
+            if self.pid in (0, 4):
+                # https://github.com/giampaolo/psutil/issues/414
+                # https://github.com/giampaolo/psutil/issues/528
+                raise AccessDenied(self.pid, self._name)
+            exe = cext.proc_exe(self.pid)
+            exe = convert_dos_path(exe)
+        return py2_strencode(exe)
 
     @wrap_exceptions
     def cmdline(self):