runtime: implement an extensible line editor

the line editor supports custom keybinds and data storage, allowing for a wide range of functionality to be implemented via plugins. included plugins include: * core: basic input and cursor movement. * history: input history storage and retrieval (unfinished) * highlight: support for colour-highlighting the line buffer (unfinished) * syntax: parses the line buffer and uses `highlight` to apply syntax highlighting (unfinished). * shell-integration: - allows a `prompt` function to be defined, which will be called to get the text to be used for the prompt - exposes key properties of the line editor to the shell environment, allowing line editor functionality to be extended via shell scripts.
2026-06-20 15:13:34 +01:00
parent f622c2eba3
commit ad8b284869
21 changed files with 1857 additions and 1 deletions
@@ -0,0 +1,223 @@
+#include "keybind.h"
+
+#include "line-editor.h"
+
+#include <fx/term/tty.h>
+
+#define KEYCODE_WILDCARD FX_KEY_RESERVED_START
+
+static FX_BST_DEFINE_SIMPLE_INSERT(
+	struct keymap_entry,
+	e_node,
+	e_code,
+	put_keymap_entry);
+static FX_BST_DEFINE_SIMPLE_GET(
+	struct keymap_entry,
+	fx_keycode,
+	e_node,
+	e_code,
+	get_keymap_entry);
+static FX_BST_DEFINE_SIMPLE_INSERT(
+	struct keybind,
+	b_node,
+	b_priority,
+	put_keybind);
+
+struct bshell_line_ed_keybind_p {
+	bshell_line_ed_keybind *kb_self;
+	struct keybind kb_bind;
+};
+
+static void keymap_entry_destroy(struct keymap_entry *entry)
+{
+	fx_bst_node *cur_bind = fx_bst_first(&entry->e_binds);
+	while (cur_bind) {
+		fx_bst_node *next_bind = fx_bst_next(cur_bind);
+		fx_bst_delete(&entry->e_binds, cur_bind);
+
+		struct keybind *keybind
+			= fx_unbox(struct keybind, cur_bind, b_node);
+		struct bshell_line_ed_keybind_p *keybind_object_p = fx_unbox(
+			struct bshell_line_ed_keybind_p,
+			keybind,
+			kb_bind);
+		bshell_line_ed_keybind_unref(keybind_object_p->kb_self);
+
+		cur_bind = next_bind;
+	}
+
+	free(entry);
+}
+
+void line_ed_cleanup_keymap(fx_bst *keymap)
+{
+	fx_bst_node *cur_entry = fx_bst_first(keymap);
+	while (cur_entry) {
+		fx_bst_node *next_entry = fx_bst_next(cur_entry);
+		fx_bst_delete(keymap, cur_entry);
+
+		struct keymap_entry *keymap_entry
+			= fx_unbox(struct keymap_entry, cur_entry, e_node);
+
+		keymap_entry_destroy(keymap_entry);
+
+		cur_entry = next_entry;
+	}
+}
+
+static fx_keycode key_string_to_code(const char *key)
+{
+	const char *tmp = key;
+	fx_keycode result = 0;
+
+	if (*key == '^') {
+		result |= FX_MOD_CTRL;
+		key++;
+	}
+
+	if (!strcmp(key, "*")) {
+		result |= KEYCODE_WILDCARD;
+	} else if (!strcmp(key, "left")) {
+		result |= FX_KEY_ARROW_LEFT;
+	} else if (!strcmp(key, "right")) {
+		result |= FX_KEY_ARROW_RIGHT;
+	} else if (!strcmp(key, "up")) {
+		result |= FX_KEY_ARROW_UP;
+	} else if (!strcmp(key, "down")) {
+		result |= FX_KEY_ARROW_DOWN;
+	} else if (!strcmp(key, "backspace")) {
+		result |= FX_KEY_BACKSPACE;
+	} else if (!strcmp(key, "return")) {
+		result |= FX_KEY_RETURN;
+	} else {
+		result |= fx_wchar_utf8_codepoint_decode(key);
+	}
+
+	return result;
+}
+
+static bshell_line_ed_keybind *line_ed_bind_key(
+	struct bshell_line_ed_p *ed,
+	const char *key,
+	bshell_line_ed_keybind_callback_t callback,
+	unsigned long priority)
+{
+	fx_keycode keycode = key_string_to_code(key);
+	if (!keycode) {
+		return NULL;
+	}
+
+	bshell_line_ed_keybind *bind = NULL;
+	bind = bshell_line_ed_keybind_create();
+
+	if (!bind) {
+		return NULL;
+	}
+
+	struct bshell_line_ed_keybind_p *bind_p
+		= fx_object_get_private(bind, BSHELL_TYPE_LINE_EDITOR_KEYBIND);
+
+	struct keymap_entry *keymap_entry
+		= get_keymap_entry(&ed->ed_keymap, keycode);
+	if (!keymap_entry) {
+		keymap_entry = calloc(1, sizeof *keymap_entry);
+		if (!keymap_entry) {
+			bshell_line_ed_keybind_unref(bind);
+			return NULL;
+		}
+
+		keymap_entry->e_code = keycode;
+		put_keymap_entry(&ed->ed_keymap, keymap_entry);
+	}
+
+	bind_p->kb_self = bind;
+	bind_p->kb_bind.b_priority = priority;
+	bind_p->kb_bind.b_callback = callback;
+	put_keybind(&keymap_entry->e_binds, &bind_p->kb_bind);
+
+	return bind;
+}
+
+bshell_line_ed_keybind *bshell_line_ed_bind_key(
+	bshell_line_ed *ed,
+	const char *key,
+	bshell_line_ed_keybind_callback_t callback,
+	unsigned long priority)
+{
+	FX_CLASS_DISPATCH_STATIC(
+		BSHELL_TYPE_LINE_EDITOR,
+		line_ed_bind_key,
+		ed,
+		key,
+		callback,
+		priority);
+}
+
+static struct bshell_line_ed_keybind_result do_handle_key(
+	struct bshell_line_ed_p *ed,
+	fx_keycode match_code,
+	fx_keycode real_code)
+{
+	struct bshell_line_ed_keybind_result result
+		= BSHELL_LINE_EDITOR_KEYBIND_RESULT(
+			BSHELL_SUCCESS,
+			BSHELL_LINE_EDITOR_KEYBIND_CONTINUE);
+
+	struct keymap_entry *keymap_entry
+		= get_keymap_entry(&ed->ed_keymap, match_code);
+	if (!keymap_entry) {
+		return result;
+	}
+
+	fx_bst_node *cur = fx_bst_last(&keymap_entry->e_binds);
+	while (cur) {
+		struct keybind *bind = fx_unbox(struct keybind, cur, b_node);
+		result = bind->b_callback(ed->ed_self, real_code);
+
+		if (result.r_status != BSHELL_SUCCESS
+		    || result.r_action != BSHELL_LINE_EDITOR_KEYBIND_CONTINUE) {
+			break;
+		}
+
+		cur = fx_bst_prev(cur);
+	}
+
+	return result;
+}
+
+void line_ed_handle_key(struct bshell_line_ed_p *ed, fx_keycode code)
+{
+	struct bshell_line_ed_keybind_result result
+		= do_handle_key(ed, code, code);
+	if (result.r_status != BSHELL_SUCCESS
+	    || result.r_action != BSHELL_LINE_EDITOR_KEYBIND_CONTINUE) {
+		return;
+	}
+
+	if (code & FX_MOD_CTRL) {
+		result = do_handle_key(
+			ed,
+			FX_MOD_CTRL | KEYCODE_WILDCARD,
+			code);
+	} else {
+		result = do_handle_key(ed, KEYCODE_WILDCARD, code);
+	}
+}
+
+static void fini(fx_object *obj, void *priv)
+{
+}
+
+FX_TYPE_CLASS_BEGIN(bshell_line_ed_keybind)
+	FX_TYPE_VTABLE_INTERFACE_BEGIN(fx_object, FX_TYPE_OBJECT)
+		FX_INTERFACE_ENTRY(to_string) = NULL;
+	FX_TYPE_VTABLE_INTERFACE_END(fx_object, FX_TYPE_OBJECT)
+FX_TYPE_CLASS_END(bshell_line_ed_keybind)
+
+FX_TYPE_DEFINITION_BEGIN(bshell_line_ed_keybind)
+	FX_TYPE_ID(0x5d842371, 0x40a3, 0x4683, 0xaff2, 0x05daa53d36b7);
+	FX_TYPE_NAME("bshell.line_editor.keybind");
+	FX_TYPE_CLASS(bshell_line_ed_keybind_class);
+	FX_TYPE_INSTANCE_PRIVATE(struct bshell_line_ed_keybind_p);
+	FX_TYPE_INSTANCE_FINI(fini);
+FX_TYPE_DEFINITION_END(bshell_line_ed_keybind)