Handle Ctrl+AltGr on Windows
Improve AltGr detection even further on Windows so we can detect the
case when Ctrl and AltGr are pressed together.
diff --git a/vncviewer/win32.c b/vncviewer/win32.c
index 30c87f1..537ff43 100644
--- a/vncviewer/win32.c
+++ b/vncviewer/win32.c
@@ -33,6 +33,9 @@
#define MAPVK_VK_TO_CHAR 2
#endif
+int has_altgr;
+HKL current_layout = 0;
+
static HANDLE thread;
static DWORD thread_id;
@@ -300,3 +303,58 @@
return NoSymbol;
}
+
+int win32_has_altgr(void)
+{
+ BYTE orig_state[256];
+ BYTE altgr_state[256];
+
+ if (current_layout == GetKeyboardLayout(0))
+ return has_altgr;
+
+ // Save current keyboard state so we can get things sane again after
+ // we're done
+ if (!GetKeyboardState(orig_state))
+ return 0;
+
+ // We press Ctrl+Alt (Windows fake AltGr) and then test every key
+ // to see if it produces a printable character. If so then we assume
+ // AltGr is used in the current layout.
+
+ has_altgr = 0;
+
+ memset(altgr_state, 0, sizeof(altgr_state));
+ altgr_state[VK_CONTROL] = 0x80;
+ altgr_state[VK_MENU] = 0x80;
+
+ for (UINT vkey = 0;vkey <= 0xff;vkey++) {
+ int ret;
+ WCHAR wstr[10];
+
+ // Need to skip this one as it is a bit magical and will trigger
+ // a false positive
+ if (vkey == VK_PACKET)
+ continue;
+
+ ret = ToUnicode(vkey, 0, altgr_state, wstr,
+ sizeof(wstr)/sizeof(wstr[0]), 0);
+ if (ret == 1) {
+ has_altgr = 1;
+ break;
+ }
+
+ if (ret == -1) {
+ // Dead key, need to clear out state before we proceed
+ do {
+ ret = ToUnicode(vkey, 0, altgr_state, wstr,
+ sizeof(wstr)/sizeof(wstr[0]), 0);
+ } while (ret < 0);
+ }
+ }
+
+ SetKeyboardState(orig_state);
+
+ current_layout = GetKeyboardLayout(0);
+
+ return has_altgr;
+}