degesch: sanitize terminal output

1 files changed, 22 insertions, 15 deletions

diff --git a/degesch.c b/degesch.c
index 5d5108e..a6826d6 100644
--- a/degesch.c
+++ b/degesch.c
@@ -2561,6 +2561,23 @@ formatter_flush_attr
 }
 
 static void
+formatter_flush_text (struct app_context *ctx, const char *text, FILE *stream)
+{
+	struct str sanitized;
+	str_init (&sanitized);
+
+	// Throw away any potentially harmful control characters
+	char *term = iconv_xstrdup (ctx->term_from_utf8, (char *) text, -1, NULL);
+	for (char *p = term; *p; p++)
+		if (!strchr ("\a\b\x1b", *p))
+			str_append_c (&sanitized, *p);
+	free (term);
+
+	fputs (sanitized.str, stream);
+	str_free (&sanitized);
+}
+
+static void
 formatter_flush (struct formatter *self, FILE *stream)
 {
 	terminal_printer_fn printer = get_attribute_printer (stream);
@@ -2579,23 +2596,13 @@ formatter_flush (struct formatter *self, FILE *stream)
 	int attribute_ignore = 0;
 	LIST_FOR_EACH (struct formatter_item, iter, self->items)
 	{
-		switch (iter->type)
-		{
-			char *term;
-		case FORMATTER_ITEM_TEXT:
-			term = iconv_xstrdup
-				(self->ctx->term_from_utf8, iter->text, -1, NULL);
-			fputs (term, stream);
-			free (term);
-			break;
-		case FORMATTER_ITEM_IGNORE_ATTR:
+		if      (iter->type == FORMATTER_ITEM_TEXT)
+			formatter_flush_text (self->ctx, iter->text, stream);
+		else if (iter->type == FORMATTER_ITEM_IGNORE_ATTR)
 			attribute_ignore += iter->attribute;
-			break;
-		default:
-			if (attribute_ignore <= 0
-			 && !formatter_flush_attr (&state, iter))
+		else if (attribute_ignore <= 0
+			&& !formatter_flush_attr (&state, iter))
 				hard_assert (!"unhandled formatter item type");
-		}
 	}
 	attribute_printer_reset (&state);
 }