fix overflow in putsna

1 files changed, 7 insertions, 0 deletions

diff --git a/vui.c b/vui.c
index caf4654..ffd5800 100644
--- a/vui.c
+++ b/vui.c
@@ -363,6 +363,7 @@ static inline void vui_outs(const char *s) {
 static inline void vui_out_flush(void) {
 	fwrite(vui_out, 1, vui_outn, stdout);
 	fflush(stdout);
+	//write(STDOUT_FILENO, vui_out, vui_outn);
 #if 0
 	static unsigned out_frame = 0;
 	FILE *f = fopen("out_log.txt", "a");
@@ -643,7 +644,13 @@ static void utf8_decode(uint32_t *dst, const char *src, unsigned n) {
 }
 
 void vui_putsna(int x, int y, const char *s, unsigned n, VuiAttr a) {
+	if (x >= (int)COLS) return;
 	if (n > COLS - x) n = COLS - x;
+	if (x < 0) {
+		n += x;
+		x = 0;
+	}
+	if (n < 1 || y < 0 || y >= (int)LINES) return;
 	utf8_decode(&CHR(x, y), s, n);
 	for (uint16_t *pa = &ATTR(x, y); n--;) *pa++ = a;
 }