lib: check for libusb init failure

src/librtlsdr.c

@@ -1298,14 +1298,16 @@ static rtlsdr_dongle_t *find_known_device(uint16_t vid, uint16_t pid)
 
 uint32_t rtlsdr_get_device_count(void)
 {
-	int i;
+	int i,r;
 	libusb_context *ctx;
 	libusb_device **list;
 	uint32_t device_count = 0;
 	struct libusb_device_descriptor dd;
 	ssize_t cnt;
 
-	libusb_init(&ctx);
+	r = libusb_init(&ctx);
+	if(r < 0)
+		return 0;
 
 	cnt = libusb_get_device_list(ctx, &list);
 
@@ -1325,7 +1327,7 @@ uint32_t rtlsdr_get_device_count(void)
 
 const char *rtlsdr_get_device_name(uint32_t index)
 {
-	int i;
+	int i,r;
 	libusb_context *ctx;
 	libusb_device **list;
 	struct libusb_device_descriptor dd;
@@ -1333,7 +1335,9 @@ const char *rtlsdr_get_device_name(uint32_t index)
 	uint32_t device_count = 0;
 	ssize_t cnt;
 
-	libusb_init(&ctx);
+	r = libusb_init(&ctx);
+	if(r < 0)
+		return "";
 
 	cnt = libusb_get_device_list(ctx, &list);
 
@@ -1373,7 +1377,9 @@ int rtlsdr_get_device_usb_strings(uint32_t index, char *manufact,
 	uint32_t device_count = 0;
 	ssize_t cnt;
 
-	libusb_init(&ctx);
+	r = libusb_init(&ctx);
+	if(r < 0)
+		return r;
 
 	cnt = libusb_get_device_list(ctx, &list);
 
@@ -1447,7 +1453,11 @@ int rtlsdr_open(rtlsdr_dev_t **out_dev, uint32_t index)
 	memset(dev, 0, sizeof(rtlsdr_dev_t));
 	memcpy(dev->fir, fir_default, sizeof(fir_default));
 
-	libusb_init(&dev->ctx);
+	r = libusb_init(&dev->ctx);
+	if(r < 0){
+		free(dev);
+		return -1;
+	}
 
 	dev->dev_lost = 1;