steam_helper: Stop waiting on the debugger when ptraced.

steam_helper/steam.cpp

@@ -1514,6 +1514,29 @@ static DWORD WINAPI steam_drm_thread(void *arg)
 
     return 0;
 }
+
+BOOL is_ptraced(void)
+{
+    char key[50];
+    int value;
+    FILE *fp = fopen("/proc/self/status", "r");
+    BOOL ret = FALSE;
+
+    if (!fp) return FALSE;
+
+    while (fscanf(fp, " %s	%d\n", key, &value) > 0)
+    {
+        if (!strcmp("TracerPid:", key))
+        {
+            ret = (value != 0);
+            break;
+        }
+    }
+
+    fclose(fp);
+    return ret;
+}
+
 int main(int argc, char *argv[])
 {
     HANDLE wait_handle = INVALID_HANDLE_VALUE;
@@ -1557,7 +1580,7 @@ int main(int argc, char *argv[])
         {
             unsigned int sleep_count = 0;
             WINE_TRACE("PROTON_WAIT_ATTACH is set, waiting for debugger...\n");
-            while (!IsDebuggerPresent())
+            while (!IsDebuggerPresent() && !is_ptraced())
             {
                 Sleep(100);
                 ++sleep_count;