dev->config might be NULL (like on MacOS X)

git-svn-id: https://svn.code.sf.net/p/gphoto/code/trunk/libgphoto2@12693 67ed7778-7388-44ab-90cf-0a291f65f57c

1 files changed, 20 insertions, 18 deletions

diff --git a/libgphoto2_port/usb/libusb.c b/libgphoto2_port/usb/libusb.c
index c06af0765..9fa28fbb7 100644
--- a/libgphoto2_port/usb/libusb.c
+++ b/libgphoto2_port/usb/libusb.c
@@ -843,28 +843,30 @@ gp_port_usb_match_mtp_device(struct usb_device *dev,int *configno, int *interfac
 	 * MTP interface descriptions, that's how they can be detected, before
 	 * we try the more esoteric "OS descriptors" (below).
 	 */
-	for (i = 0; i < dev->descriptor.bNumConfigurations; i++) {
-		unsigned int j;
-		for (j = 0; j < dev->config[i].bNumInterfaces; j++) {
-			int k;
-			for (k = 0; k < dev->config[i].interface[j].num_altsetting; k++) {
-				buf[0] = '\0';
-				ret = usb_get_string_simple(devh, 
-					dev->config[i].interface[j].altsetting[k].iInterface, 
-					(char *) buf, 
-					1024);
-				if (ret < 3)
-					continue;
-				if (strcmp((char *) buf, "MTP") == 0) {
-					gp_log (GP_LOG_DEBUG, "mtp matcher", "Configuration %d, interface %d, altsetting %d:\n", i, j, k);
-					gp_log (GP_LOG_DEBUG, "mtp matcher", "   Interface description contains the string \"MTP\"\n");
-					gp_log (GP_LOG_DEBUG, "mtp matcher", "   Device recognized as MTP, no further probing.\n");
-					goto found;
+	if (dev->config) {
+		for (i = 0; i < dev->descriptor.bNumConfigurations; i++) {
+			unsigned int j;
+
+			for (j = 0; j < dev->config[i].bNumInterfaces; j++) {
+				int k;
+				for (k = 0; k < dev->config[i].interface[j].num_altsetting; k++) {
+					buf[0] = '\0';
+					ret = usb_get_string_simple(devh, 
+						dev->config[i].interface[j].altsetting[k].iInterface, 
+						(char *) buf, 
+						1024);
+					if (ret < 3)
+						continue;
+					if (strcmp((char *) buf, "MTP") == 0) {
+						gp_log (GP_LOG_DEBUG, "mtp matcher", "Configuration %d, interface %d, altsetting %d:\n", i, j, k);
+						gp_log (GP_LOG_DEBUG, "mtp matcher", "   Interface description contains the string \"MTP\"\n");
+						gp_log (GP_LOG_DEBUG, "mtp matcher", "   Device recognized as MTP, no further probing.\n");
+						goto found;
+					}
 				}
 			}
 		}
 	}
-
 	/* get string descriptor at 0xEE */
 	ret = usb_get_descriptor (devh, 0x03, 0xee, buf, sizeof(buf));
 	if (ret > 0) gp_log_data("get_MS_OSD",buf, ret);