3 files changed, 8 insertions, 8 deletions
diff --git a/camlibs/canon/crc.c b/camlibs/canon/crc.c
index 5f44db07f..17b8990da 100644
--- a/camlibs/canon/crc.c
+++ b/camlibs/canon/crc.c
@@ -223,7 +223,7 @@ find_init (int len)
  *   program with a message to stderr.
  *
  */
-unsigned short
+int
 canon_psa50_gen_crc (const unsigned char *pkt, int len)
 {
 	int init;
@@ -232,7 +232,7 @@ canon_psa50_gen_crc (const unsigned char *pkt, int len)
 	if (init != -1)
 		return chksum (init, len, pkt);
 	fprintf (stderr, _("FATAL ERROR: initial CRC value for length %d unknown\n"), len);
-	exit (1);
+	return -1;
 }
 
 
@@ -245,7 +245,7 @@ guess (const unsigned char *m, int len, int crc)
 		if (chksum (i, len, m) == crc)
 			return i;
 	fprintf (stderr, _("unable to guess initial CRC value\n"));
-	exit (1);
+	return -1;
 }
 
 /**
diff --git a/camlibs/canon/crc.h b/camlibs/canon/crc.h
index c2bdd66ce..0e786ca8e 100644
--- a/camlibs/canon/crc.h
+++ b/camlibs/canon/crc.h
@@ -1,7 +1,7 @@
 #ifndef CRC_H
 #define CRC_H
 
-unsigned short canon_psa50_gen_crc(const unsigned char *pkt, int len);
+int canon_psa50_gen_crc(const unsigned char *pkt, int len);
 int canon_psa50_chk_crc(const unsigned char *pkt, int len, unsigned short crc);
 
 #endif
diff --git a/camlibs/canon/serial.c b/camlibs/canon/serial.c
index de99a9a45..0c8568050 100644
--- a/camlibs/canon/serial.c
+++ b/camlibs/canon/serial.c
@@ -388,6 +388,8 @@ canon_serial_send_packet (Camera *camera, unsigned char type, unsigned char seq,
 	if (type == PKT_EOT || type == PKT_ACK || type == PKT_NACK)
 		len = 2;	/* @@@ hack */
 	crc = canon_psa50_gen_crc (hdr, len + PKT_HDR_LEN);
+	if (crc == -1)
+		return GP_ERROR;
 	pkt[len] = crc & 0xff;
 	pkt[len + 1] = crc >> 8;
 
@@ -720,10 +722,8 @@ canon_serial_recv_msg (Camera *camera, unsigned char mtype, unsigned char dir, u
 			if (msg_pos + len > msg_size || !msg) {
 				msg_size *= 2;
 				msg = realloc (msg, msg_size);
-				if (!msg) {
-					perror ("realloc");
-					exit (1);
-				}
+				if (!msg)
+					return NULL;
 			}
 			memcpy (msg + msg_pos, frag, len);
 			msg_pos += len;