small fixes, and display error locations

Author: braindigitalis

os/programs/test2.rrbasic

@@ -0,0 +1,18 @@
+d$ = ARGS$
+
+IF d$ = "/" THEN
+    parent$ = "/"
+ELSE
+    i = LEN(d$)
+    WHILE i > 1 AND MID$(d$, i, 1) <> "/"
+        i = i - 1
+    ENDWHILE
+
+    IF i <= 1 THEN
+        parent$ = "/"
+    ELSE
+        parent$ = LEFT$(d$, i - 1)
+    ENDIF
+ENDIF
+
+PRINT parent$

src/basic/flow_control.c

@@ -13,13 +13,13 @@ bool conditional(struct basic_ctx* ctx)
 	strlcpy(current_line, ctx->ptr, pos ? pos - ctx->ptr + 1 : end - ctx->ptr + 1);
 	for (char* n = current_line; *n && *n != '\n'; ++n) {
 		if (strlen(n) >= 2 && isalnum(*n) && *(n + 1) == '$') {
-			stringlike = true; /* String variable */
+			stringlike = true; // String variable
 			break;
 		} else if (strlen(n) >= 2 && isalnum(*n) && *(n + 1) == '#') {
-			real = true; /* Real variable */
+			real = true; // Real variable
 			break;
 		} else if (strlen(n) >= 3 && isdigit(*n) && *(n + 1) == '.' && isdigit(*(n + 2))) {
-			real = true; /* Decimal number */
+			real = true; // Decimal number
 			break;
 		} else if (strlen(n) >= 5 && *n == ' ' && *(n + 1) == 'T' && *(n + 2) == 'H' && *(n + 3) == 'E' && *(n + 4) == 'N') {
 			break;
@@ -47,13 +47,10 @@ void else_statement(struct basic_ctx* ctx)
 	 */
 	accept_or_return(ELSE, ctx);
 	accept_or_return(NEWLINE, ctx);
-	while (tokenizer_token(ctx) != END && !tokenizer_finished(ctx)) {
+	while (tokenizer_token(ctx) != ENDIF && !tokenizer_finished(ctx)) {
 		tokenizer_next(ctx);
-		if (*ctx->ptr == 'I' && *(ctx->ptr+1) == 'F') {
-			accept_or_return(IF, ctx);
-			accept_or_return(NEWLINE, ctx);
-			return;
-		}
+		accept_or_return(NEWLINE, ctx);
+		return;
 	}
 	tokenizer_error_print(ctx, "Block IF/THEN/ELSE without ENDIF");
 }

src/basic/tokenizer.c

@@ -399,6 +399,22 @@ void tokenizer_error_print(struct basic_ctx* ctx, const char* error)
 			}
 			setforeground(COLOUR_LIGHTRED);
 			kprintf("Error on line %ld: %s\n", ctx->current_linenum, error);
+			setforeground(COLOUR_DARKRED);
+			ub_line_ref* line = hashmap_get(ctx->lines, &(ub_line_ref){ .line_number = ctx->current_linenum });
+			if (line) {
+				char l[MAX_STRINGLEN];
+				char* p = strchr(line->ptr, '\n');
+				strlcpy(l, line->ptr, p ? p - line->ptr + 1 : strlen(line->ptr));
+				size_t offset = ctx->ptr - line->ptr;
+				if (offset > strlen(l)) {
+					offset = 0;
+				}
+				kprintf("%s\n", l);
+				for (size_t x = 0; x < offset - 1; ++x) {
+					put(' ');
+				}
+				kprintf("^\n");
+			}
 			setforeground(COLOUR_WHITE);
 			ctx->ended = true;
 		}