frontend: add a line editor for shell input

frontend/line-ed/hooks/highlight.c

@@ -0,0 +1,131 @@
+#include "highlight.h"
+
+#include <ivy/lang/lex.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define LEX_SOURCE_TO_HIGHLIGHT(p)                                             \
+	((struct highlight_hook *)((char *)p                                   \
+	                           - offsetof(struct highlight_hook, hook_src)))
+#define HOOK_TO_HIGHLIGHT(p)                                                   \
+	((struct highlight_hook *)((char *)p                                   \
+	                           - offsetof(struct highlight_hook, hook_base)))
+
+static enum ivy_status readline(
+	struct ivy_line_source *source, char *out, size_t max, size_t *read,
+	const char *scope_type)
+{
+	struct highlight_hook *highlight = LEX_SOURCE_TO_HIGHLIGHT(source);
+	const char *bufp = highlight->hook_bufp;
+
+	size_t r = 0;
+	for (size_t i = 0; i < max; i++) {
+		char c = *bufp;
+
+		out[i] = c;
+
+		if (c == '\0') {
+			break;
+		}
+
+		r++;
+		bufp++;
+
+		if (c == '\n') {
+			break;
+		}
+	}
+
+	highlight->hook_bufp = bufp;
+	*read = r;
+	return r > 0 ? IVY_OK : IVY_ERR_EOF;
+}
+
+static void highlight_token(
+	struct line_ed *ed, struct ivy_token *tok, struct s_tty_vmode *vmode)
+{
+	/* TODO re-enable this once tokens contain positional info */
+#if 0
+	line_ed_put_highlight(
+		ed, tok->t_start_col - 1, tok->t_start_row - 1,
+		tok->t_end_col - 1, tok->t_end_row - 1, vmode);
+#endif
+}
+
+static void buffer_modified(struct line_ed *ed, struct line_ed_hook *hook)
+{
+#if 0
+	struct highlight_hook *highlight = HOOK_TO_HIGHLIGHT(hook);
+	line_ed_clear_highlights(ed);
+	lex_reset(highlight->hook_lex);
+	highlight->hook_bufp = ed->l_buf;
+
+	struct s_tty_vmode vmode_number = MAKE_VMODE(
+		MAKE_COLOUR_16(TTY_COLOUR16_CYAN), MAKE_COLOUR_DEFAULT(),
+		TTY_ATTRIB_NORMAL);
+	struct s_tty_vmode vmode_keyword = MAKE_VMODE(
+		MAKE_COLOUR_16(TTY_COLOUR16_BRIGHT_YELLOW),
+		MAKE_COLOUR_DEFAULT(), TTY_ATTRIB_BOLD);
+	struct s_tty_vmode vmode_var = MAKE_VMODE(
+		MAKE_COLOUR_16(TTY_COLOUR16_MAGENTA), MAKE_COLOUR_DEFAULT(),
+		TTY_ATTRIB_ITALIC);
+
+	struct lex_token *tok;
+	while (1) {
+		tok = lex_advance(highlight->hook_lex);
+		if (!tok) {
+			break;
+		}
+
+		if (tok->t_start_col == 0) {
+			lex_token_destroy(tok);
+			continue;
+		}
+
+		switch (tok->t_type) {
+		case TOK_NUMBER:
+			highlight_token(ed, tok, &vmode_number);
+			break;
+		case TOK_KEYWORD:
+			highlight_token(ed, tok, &vmode_keyword);
+			break;
+		case TOK_VAR:
+			highlight_token(ed, tok, &vmode_var);
+			break;
+		default:
+			break;
+		}
+
+		lex_token_destroy(tok);
+	}
+#endif
+}
+
+extern struct highlight_hook *highlight_hook_create(void)
+{
+#if 0
+	struct highlight_hook *out = malloc(sizeof *out);
+	if (!out) {
+		return NULL;
+	}
+
+	memset(out, 0x0, sizeof *out);
+
+	out->hook_lex = lex_create(LEX_MODE_SPECULATIVE);
+	out->hook_base.hook_buffer_modified = buffer_modified;
+	out->hook_src.s_readline = readline;
+
+	lex_set_source(out->hook_lex, &out->hook_src);
+
+	return out;
+#endif
+	return NULL;
+}
+
+extern void highlight_hook_destroy(struct highlight_hook *hook)
+{
+#if 0
+	lex_destroy(hook->hook_lex);
+	free(hook);
+#endif
+}

frontend/line-ed/hooks/highlight.h

@@ -0,0 +1,20 @@
+#ifndef LINE_ED_HOOKS_HIGHLIGHT_H_
+#define LINE_ED_HOOKS_HIGHLIGHT_H_
+
+#include "../line-ed.h"
+
+#include <ivy/lang/lex.h>
+
+struct lex;
+
+struct highlight_hook {
+	struct line_ed_hook hook_base;
+	struct ivy_line_source hook_src;
+	const char *hook_bufp;
+	struct lex *hook_lex;
+};
+
+extern struct highlight_hook *highlight_hook_create(void);
+extern void highlight_hook_destroy(struct highlight_hook *hook);
+
+#endif