[console] Support changing keyboard map at runtime

Provide the special keyboard map named "dynamic" which allows the
active keyboard map to be selected at runtime via the ${keymap}
setting, e.g.:

  #define KEYBOARD_MAP dynamic

  iPXE> set keymap uk

Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/core/dynkeymap.c

@@ -0,0 +1,131 @@
+/*
+ * Copyright (C) 2022 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., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ *
+ * You can also choose to distribute this program under the terms of
+ * the Unmodified Binary Distribution Licence (as given in the file
+ * COPYING.UBDL), provided that you have satisfied its requirements.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
+
+/** @file
+ *
+ * Dynamic keyboard mappings
+ *
+ */
+
+#include <stdlib.h>
+#include <errno.h>
+#include <ipxe/settings.h>
+#include <ipxe/keymap.h>
+
+/**
+ * Require a keyboard map
+ *
+ * @v name		Keyboard map name
+ */
+#define REQUIRE_KEYMAP( name ) REQUIRE_OBJECT ( keymap_ ## name )
+
+/** Keyboard map setting */
+const struct setting keymap_setting __setting ( SETTING_MISC, keymap ) = {
+	.name = "keymap",
+	.description = "Keyboard map",
+	.type = &setting_type_string,
+};
+
+/**
+ * Apply keyboard map settings
+ *
+ * @ret rc		Return status code
+ */
+static int keymap_apply ( void ) {
+	struct keymap *keymap;
+	char *name;
+	int rc;
+
+	/* Fetch keyboard map name */
+	fetch_string_setting_copy ( NULL, &keymap_setting, &name );
+
+	/* Identify keyboard map */
+	if ( name ) {
+		/* Identify named keyboard map */
+		keymap = keymap_find ( name );
+		if ( ! keymap ) {
+			DBGC ( &keymap_setting, "KEYMAP could not identify "
+			       "\"%s\"\n", name );
+			rc = -ENOENT;
+			goto err_unknown;
+		}
+	} else {
+		/* Use default keyboard map */
+		keymap = NULL;
+	}
+
+	/* Set keyboard map */
+	keymap_set ( keymap );
+
+	/* Success */
+	rc = 0;
+
+ err_unknown:
+	free ( name );
+	return rc;
+}
+
+/** Keyboard map setting applicator */
+struct settings_applicator keymap_applicator __settings_applicator = {
+	.apply = keymap_apply,
+};
+
+/* Provide virtual "dynamic" keyboard map for linker */
+PROVIDE_SYMBOL ( obj_keymap_dynamic );
+
+/* Drag in keyboard maps via keymap_setting */
+REQUIRING_SYMBOL ( keymap_setting );
+
+/* Require all known keyboard maps */
+REQUIRE_KEYMAP ( al );
+REQUIRE_KEYMAP ( by );
+REQUIRE_KEYMAP ( cf );
+REQUIRE_KEYMAP ( cz );
+REQUIRE_KEYMAP ( de );
+REQUIRE_KEYMAP ( dk );
+REQUIRE_KEYMAP ( es );
+REQUIRE_KEYMAP ( et );
+REQUIRE_KEYMAP ( fi );
+REQUIRE_KEYMAP ( fr );
+REQUIRE_KEYMAP ( gr );
+REQUIRE_KEYMAP ( hu );
+REQUIRE_KEYMAP ( il );
+REQUIRE_KEYMAP ( it );
+REQUIRE_KEYMAP ( lt );
+REQUIRE_KEYMAP ( mk );
+REQUIRE_KEYMAP ( mt );
+REQUIRE_KEYMAP ( nl );
+REQUIRE_KEYMAP ( no );
+REQUIRE_KEYMAP ( no_latin1 );
+REQUIRE_KEYMAP ( pl );
+REQUIRE_KEYMAP ( pt );
+REQUIRE_KEYMAP ( ro );
+REQUIRE_KEYMAP ( ru );
+REQUIRE_KEYMAP ( se );
+REQUIRE_KEYMAP ( sg );
+REQUIRE_KEYMAP ( sr_latin );
+REQUIRE_KEYMAP ( ua );
+REQUIRE_KEYMAP ( uk );
+REQUIRE_KEYMAP ( us );

src/core/keymap.c

@@ -23,6 +23,7 @@
 
 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 
+#include <string.h>
 #include <ctype.h>
 #include <ipxe/keys.h>
 #include <ipxe/keymap.h>
@@ -49,7 +50,7 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 static TABLE_START ( keymap_start, KEYMAP );
 
 /** Current keyboard mapping */
-static struct keymap *keymap = keymap_start;
+static struct keymap *keymap_current = keymap_start;
 
 /**
  * Remap a key
@@ -58,6 +59,7 @@ static struct keymap *keymap = keymap_start;
  * @ret mapped		Mapped character
  */
 unsigned int key_remap ( unsigned int character ) {
+	struct keymap *keymap = keymap_current;
 	unsigned int mapped = ( character & KEYMAP_MASK );
 	struct keymap_key *key;
 
@@ -88,6 +90,42 @@ unsigned int key_remap ( unsigned int character ) {
 	/* Clear flags */
 	mapped &= ASCII_MASK;
 
-	DBGC2 ( &keymap, "KEYMAP mapped %04x => %02x\n", character, mapped );
+	DBGC2 ( &keymap_current, "KEYMAP mapped %04x => %02x\n",
+		character, mapped );
 	return mapped;
 }
+
+/**
+ * Find keyboard map by name
+ *
+ * @v name		Keyboard map name
+ * @ret keymap		Keyboard map, or NULL if not found
+ */
+struct keymap * keymap_find ( const char *name ) {
+	struct keymap *keymap;
+
+	/* Find matching keyboard map */
+	for_each_table_entry ( keymap, KEYMAP ) {
+		if ( strcmp ( keymap->name, name ) == 0 )
+			return keymap;
+	}
+
+	return NULL;
+}
+
+/**
+ * Set keyboard map
+ *
+ * @v keymap		Keyboard map, or NULL to use default
+ */
+void keymap_set ( struct keymap *keymap ) {
+
+	/* Use default keymap if none specified */
+	if ( ! keymap )
+		keymap = keymap_start;
+
+	/* Set new keyboard map */
+	if ( keymap != keymap_current )
+		DBGC ( &keymap_current, "KEYMAP using \"%s\"\n", keymap->name );
+	keymap_current = keymap;
+}

src/include/ipxe/errfile.h

@@ -395,6 +395,7 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 #define ERRFILE_efi_cachedhcp	      ( ERRFILE_OTHER | 0x00550000 )
 #define ERRFILE_linux_sysfs	      ( ERRFILE_OTHER | 0x00560000 )
 #define ERRFILE_linux_acpi	      ( ERRFILE_OTHER | 0x00570000 )
+#define ERRFILE_dynkeymap	      ( ERRFILE_OTHER | 0x00580000 )
 
 /** @} */
 

src/include/ipxe/keymap.h

@@ -73,5 +73,7 @@ struct keymap {
 #define KEYMAP_ALTGR 0x0800
 
 extern unsigned int key_remap ( unsigned int character );
+extern struct keymap * keymap_find ( const char *name );
+extern void keymap_set ( struct keymap *keymap );
 
 #endif /* _IPXE_KEYMAP_H */