1 files changed, 18 insertions, 11 deletions

diff --git a/tools/notify-dns-slaves.c b/tools/notify-dns-slaves.c
index e2c3325..65e5a5a 100644
--- a/tools/notify-dns-slaves.c
+++ b/tools/notify-dns-slaves.c
@@ -725,41 +725,48 @@ static void
 stdin_callback (int fd, int type, void *arg)
 {
 	char *line;
-	int num;
+	int num, rc;
 
 	assert (fd == 0);
 
-	num = read (fd, stdin_buffer + stdin_offset, LINE_LENGTH - stdin_offset);
-	if (num < 0) {
+	rc = read (fd, stdin_buffer + stdin_offset, LINE_LENGTH - stdin_offset);
+	if (rc < 0) {
 		if (errno == EAGAIN || errno == EINTR)
 			return;
 		warningx ("couldn't read from stdin");
 		input_complete = 1;
-	} else if (num == 0) {
+	} else if (rc == 0) {
 		debug ("input closed");
 		input_complete = 1;
 	} else {
-		stdin_offset += num;
+		stdin_offset += rc;
+		assert (stdin_offset <= LINE_LENGTH);
 	}
 
 	do {
-		line = strchr (stdin_buffer, '\n');
+		line = memchr (stdin_buffer, '\n', stdin_offset);
+
+		if (line) {
+			num = (line - stdin_buffer) + 1;
 
-		if (!line && input_complete)
+		} else if (!line && input_complete) {
 			line = stdin_buffer + stdin_offset;
+			num = line - stdin_buffer;
 
-		if (!line && stdin_offset >= LINE_LENGTH) {
+		} else if (!line && stdin_offset >= LINE_LENGTH) {
 			warningx ("input line too long");
 			line = stdin_buffer + LINE_LENGTH;
-		}
+			num = LINE_LENGTH;
 
-		if (!line) /* Wait for more data */
+		} else {
+			/* Wait for more data */
 			break;
+		}
 
 		*line = 0;
-		num = (line + 1) - stdin_buffer;
 
 		process_stdin_line (stdin_buffer);
+		assert (stdin_offset >= num);
 		stdin_offset = stdin_offset - num;
 		if (stdin_offset)
 			memmove (stdin_buffer, stdin_buffer + num, stdin_offset);