debug: add is_interactive_console query

CMakeLists.txt

@@ -124,6 +124,7 @@ if (NOT WIN32)
         memory/system.hpp
         debug_posix.cpp
         debug/crash_posix.cpp
+        debug/system_posix.cpp
         io_posix.cpp
         io_posix.hpp
         library_posix.hpp
@@ -147,6 +148,7 @@ if (WIN32)
         APPEND UTIL_FILES
         debug_win32.cpp
         debug/crash_win32.cpp
+        debug/system_win32.cpp
         exe_win32.cpp
         io_win32.cpp
         io_win32.hpp

debug/system.hpp

@@ -16,4 +16,9 @@ void force_console (void);
 ///////////////////////////////////////////////////////////////////////////////
 namespace cruft::debug {
     void init (void);
+
+
+    /// Return true if the application appears to be running as an
+    /// interactive console application.
+    bool is_interactive_console (void);
 }

debug/system_posix.cpp

@@ -0,0 +1,10 @@
+#include "./system.hpp"
+
+#include <unistd.h>
+
+
+bool
+cruft::debug::is_interactive_console (void)
+{
+    return isatty (STDIN_FILENO);
+}

debug/system_win32.cpp

@@ -0,0 +1,14 @@
+#include "./system.hpp"
+
+#include <cruft/util/win32/windows.hpp>
+
+
+bool cruft::debug::is_interactive_console (void)
+{
+    HWND console_window = GetConsoleWindow ();
+
+    DWORD dwProcessId;
+    GetWindowThreadProcessId (console_window, &dwProcessId);
+
+    return GetCurrentProcessId () == dwProcessId;
+}