sob

commit 44fdd353a9864ddb98cf5ef72f57936c42805038
parent f9bbf270b93c85592b54d7d2c6b4cb769feecc64
Author: Hiltjo Posthuma <hiltjo@codemadness.org>
Date:   Sat,  4 Oct 2014 12:36:16 +0000

do some extra checks to be safe

Diffstat:
M
sob.c
 | 
21
+++++++++++++++------

1 file changed, 15 insertions(+), 6 deletions(-)
diff --git a/sob.c b/sob.c
@@ -151,7 +151,7 @@ utfuntilchar(size_t *b, size_t *u, int (*f)(int), int dir)
 		}
 
 	} else {
-		while(*u > 0) {
+		while(*u > 0 && *b > 0) {
 			if(f(line.line[*b - 1]))
 				break;
 			if((n = utfprevn(line.line, *b, 1)) == 0)
@@ -289,10 +289,14 @@ line_cursor_begin(void)
 static void
 line_cursor_prev(void)
 {
+	size_t n;
+
 	if(line.utfpos <= 0)
 		return;
+	if((n = utfprevn(line.line, line.bytepos, 1)) == 0)
+		return;
 
-	line.bytepos -= utfprevn(line.line, line.bytepos, 1);
+	line.bytepos -= n;
 	line.utfpos--;
 	line_cursor_move(line.utfpos);
 }
@@ -300,10 +304,14 @@ line_cursor_prev(void)
 static void
 line_cursor_next(void)
 {
+	size_t n;
+
 	if(line.utfpos >= line.utflen)
 		return;
 
-	line.bytepos += utfnextn(line.line, line.bytepos, 1);
+	if((n = utfnextn(line.line, line.bytepos, 1)) == 0)
+		return;
+	line.bytepos += n;
 	line.utfpos++;
 	line_cursor_move(line.utfpos);
 }
@@ -332,7 +340,8 @@ line_delcharnext(void)
 	if(line.utfpos == line.utflen || line.utflen <= 0)
 		return;
 
-	siz = utfnextn(line.line, line.bytepos, 1);
+	if((siz = utfnextn(line.line, line.bytepos, 1)) == 0)
+		return;
 	memmove(&line.line[line.bytepos], &line.line[line.bytepos + siz],
 	        line.bytesiz - line.bytepos - siz);
 
@@ -348,8 +357,8 @@ line_delcharprev(void)
 
 	if(line.utfpos <= 0 || line.utflen <= 0)
 		return;
-
-	siz = utfprevn(line.line, line.bytepos, 1);
+	if((siz = utfprevn(line.line, line.bytepos, 1)) == 0)
+		return;
 
 	memmove(&line.line[line.bytepos - siz], &line.line[line.bytepos],
 	        line.bytesiz - line.bytepos);