summaryrefslogtreecommitdiffstats
path: root/contrib/syslinux-4.02/gpxe/src/core/getkey.c
diff options
context:
space:
mode:
Diffstat (limited to 'contrib/syslinux-4.02/gpxe/src/core/getkey.c')
-rw-r--r--contrib/syslinux-4.02/gpxe/src/core/getkey.c83
1 files changed, 83 insertions, 0 deletions
diff --git a/contrib/syslinux-4.02/gpxe/src/core/getkey.c b/contrib/syslinux-4.02/gpxe/src/core/getkey.c
new file mode 100644
index 0000000..dbd074c
--- /dev/null
+++ b/contrib/syslinux-4.02/gpxe/src/core/getkey.c
@@ -0,0 +1,83 @@
+/*
+ * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <ctype.h>
+#include <console.h>
+#include <gpxe/process.h>
+#include <gpxe/keys.h>
+#include <gpxe/timer.h>
+
+/** @file
+ *
+ * Special key interpretation
+ *
+ */
+
+#define GETKEY_TIMEOUT ( TICKS_PER_SEC / 4 )
+
+/**
+ * Read character from console if available within timeout period
+ *
+ * @v timeout Timeout period, in ticks
+ * @ret character Character read from console
+ */
+static int getchar_timeout ( unsigned long timeout ) {
+ unsigned long expiry = ( currticks() + timeout );
+
+ while ( currticks() < expiry ) {
+ step();
+ if ( iskey() )
+ return getchar();
+ }
+
+ return -1;
+}
+
+/**
+ * Get single keypress
+ *
+ * @ret key Key pressed
+ *
+ * The returned key will be an ASCII value or a KEY_XXX special
+ * constant. This function differs from getchar() in that getchar()
+ * will return "special" keys (e.g. cursor keys) as a series of
+ * characters forming an ANSI escape sequence.
+ */
+int getkey ( void ) {
+ int character;
+ unsigned int n = 0;
+
+ character = getchar();
+ if ( character != ESC )
+ return character;
+
+ while ( ( character = getchar_timeout ( GETKEY_TIMEOUT ) ) >= 0 ) {
+ if ( character == '[' )
+ continue;
+ if ( isdigit ( character ) ) {
+ n = ( ( n * 10 ) + ( character - '0' ) );
+ continue;
+ }
+ if ( character >= 0x40 )
+ return KEY_ANSI ( n, character );
+ }
+
+ return ESC;
+}