initial commit

keymap.c

@@ -0,0 +1,170 @@
+// SPDX-License-Identifier: GPL-3.0-only
+/*
+ * XKB keymap manager.
+ *
+ * Copyright (c) 2024, Richard Acayan. All rights reserved.
+ */
+
+#include <ctype.h>
+#include <fcntl.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <xkbcommon/xkbcommon.h>
+#include <xkbcommon/xkbcommon-keysyms.h>
+
+#include "keymap.h"
+#include "layout.h"
+#include "ufkbd.h"
+
+static int write_keysym(int fd, xkb_keysym_t sym)
+{
+	char *name;
+	int len, ret;
+
+	len = xkb_keysym_get_name(sym, NULL, 0);
+	if (len == -1)
+		return len;
+
+	name = malloc((size_t) len + 1);
+	if (name == NULL)
+		return -1;
+
+	xkb_keysym_get_name(sym, name, (size_t) len + 1);
+
+	ret = dprintf(fd, "%s", name);
+
+	free(name);
+	return ret;
+}
+
+static int maybe_write_modmap(int fd, int keyid, xkb_keysym_t sym)
+{
+	if (sym == XKB_KEY_Shift_L || sym == XKB_KEY_Shift_R)
+		return dprintf(fd, "    modifier_map Shift { <I%03d> };\n",
+			       keyid);
+	else if (sym == XKB_KEY_Control_L || sym == XKB_KEY_Control_R)
+		return dprintf(fd, "    modifier_map Control { <I%03d> };\n",
+			       keyid);
+	else if (sym == XKB_KEY_Alt_L || sym == XKB_KEY_Alt_R)
+		return dprintf(fd, "    modifier_map Mod1 { <I%03d> };\n",
+			       keyid);
+
+	return 0;
+}
+
+int ufkbd_keymap_add_key(struct ufkbd_keymap *keymap, xkb_keysym_t keysym)
+{
+	xkb_keysym_t upper;
+	int len;
+	int keyid;
+
+	keyid = keymap->count;
+	if (keyid >= 256)
+		return -1;
+
+	upper = xkb_keysym_to_upper(keysym);
+
+	len = dprintf(keymap->fd, "    key <I%03d> { [ ", keyid);
+	if (len == -1)
+		return len;
+	keymap->size += len;
+
+	len = write_keysym(keymap->fd, keysym);
+	if (len == -1)
+		return len;
+	keymap->size += len;
+
+	len = dprintf(keymap->fd, ", ");
+	if (len == -1)
+		return len;
+	keymap->size += len;
+
+	len = write_keysym(keymap->fd, upper);
+	if (len == -1)
+		return len;
+	keymap->size += len;
+
+	len = dprintf(keymap->fd, " ] };\n");
+	if (len == -1)
+		return len;
+	keymap->size += len;
+
+	len = maybe_write_modmap(keymap->fd, keyid, keysym);
+	if (len == -1)
+		return len;
+	keymap->size += len;
+
+	keymap->count++;
+
+	return keyid;
+}
+
+void ufkbd_keymap_end(struct ufkbd_keymap *keymap)
+{
+	int i;
+	int fd = keymap->fd;
+	size_t written;
+
+	written = dprintf(fd, "  };\n"
+			      "\n"
+			      "  xkb_keycodes \"ufkbd\" {\n"
+			      "    minimum = 8;\n"
+			      "    maximum = 255;\n");
+
+	for (i = 8; i < keymap->count; i++)
+		written += dprintf(fd, "    <I%03d> = %d;\n", i, i);
+
+	written += dprintf(fd, "    indicator 1 = \"Caps Lock\";\n"
+			       "  };\n"
+			       "\n"
+			       "  xkb_types \"ufkbd\" {\n"
+			       "    type \"TWO_LEVEL\" {\n"
+			       "        modifiers = Shift;\n"
+			       "        map[Shift] = Level2;\n"
+			       "        level_name[Level1] = \"Base\";\n"
+			       "        level_name[Level2] = \"Shift\";\n"
+			       "    };\n"
+			       "  };\n"
+			       "\n"
+			       "  xkb_compatibility \"ufkbd\" {\n"
+			       "  };\n"
+			       "};\n");
+
+	keymap->size += written;
+}
+
+struct ufkbd_keymap *ufkbd_keymap_init(void)
+{
+	struct ufkbd_keymap *keymap;
+	intmax_t pid;
+
+	keymap = malloc(sizeof(*keymap));
+	if (keymap == NULL)
+		return NULL;
+
+	pid = getpid();
+	snprintf(keymap->path, 256, "/tmp/ufkbd-keymap-pid%ju", pid);
+
+	keymap->fd = open(keymap->path, O_RDWR | O_CREAT | O_TRUNC, 0644);
+	if (keymap->fd == -1)
+		goto err;
+
+	keymap->count = 8;
+	keymap->size = dprintf(keymap->fd, "xkb_keymap {\n"
+					   "  xkb_symbols \"ufkbd\" {\n");
+
+	return keymap;
+
+err:
+	free(keymap);
+	return NULL;
+}
+
+void ufkbd_keymap_uninit(struct ufkbd_keymap *keymap)
+{
+	close(keymap->fd);
+	unlink(keymap->path);
+	free(keymap);
+}