Check for failures from libusb_init() in the libusb-1.0 glue code.

src/libusb1-glue.c

 /*
  * \file libusb1-glue.c
  * Low-level USB interface glue towards libusb.
  *
  * Copyright (C) 2005-2007 Richard A. Low <richard@wentnet.com>
  * Copyright (C) 2005-2012 Linus Walleij <triad@df.lth.se>
  * Copyright (C) 2006-2012 Marcus Meissner
  * Copyright (C) 2007 Ted Bullock
  * Copyright (C) 2008 Chris Bagwell <chris@cnpbagwell.com>
  *
@@ skipping 66 matching lines @@
 };
 typedef struct mtpdevice_list_struct mtpdevice_list_t;
 
 static const LIBMTP_device_entry_t mtp_device_table[] = {
 /* We include an .h file which is shared between us and libgphoto2 */
 #include "music-players.h"
 };
 static const int mtp_device_table_size = sizeof(mtp_device_table) / sizeof(LIBMTP_device_entry_t);
 
 // Local functions
-static void init_usb();
+static LIBMTP_error_number_t init_usb();
 static void close_usb(PTP_USB* ptp_usb);
 static int find_interface_and_endpoints(libusb_device *dev,
                                         uint8_t *interface,
                                         int* inep,
                                         int* inep_maxpacket,
                                         int* outep,
                                         int* outep_maxpacket,
                                         int* intep);
 static void clear_stall(PTP_USB* ptp_usb);
 static int init_ptp_usb (PTPParams* params, PTP_USB* ptp_usb, libusb_device* dev);
@@ skipping 20 matching lines @@
  *        value means failure.
  */
 int LIBMTP_Get_Supported_Devices_List(LIBMTP_device_entry_t ** const devices, int * const numdevs)
 {
   *devices = (LIBMTP_device_entry_t *) &mtp_device_table;
   *numdevs = mtp_device_table_size;
   return 0;
 }
 
 
-static void init_usb()
+static LIBMTP_error_number_t init_usb()
 {
   /*
    * Some additional libusb debugging please.
    * We use the same level debug between MTP and USB.
    */
-  libusb_init(NULL);
+  if (libusb_init(NULL) < 0) {
+    LIBMTP_ERROR("Libusb1 init failed\n");
+    return LIBMTP_ERROR_USB_LAYER;
+  }
 
   if ((LIBMTP_debug & LIBMTP_DEBUG_USB) != 0)
     libusb_set_debug(NULL,9);
+  return LIBMTP_ERROR_NONE;
 }
 
 /**
  * Small recursive function to append a new usb_device to the linked list of
  * USB MTP devices
  * @param devlist dynamic linked list of pointers to usb devices with MTP
  *        properties, to be extended with new device.
  * @param newdevice the new device to add.
  * @param bus_location bus for this device.
  * @return an extended array or NULL on failure.
@@ skipping 323 matching lines @@
  *        to the list).
  * @return LIBMTP_ERROR_NONE implies that devices have been found, scan the list
  *        appropriately. LIBMTP_ERROR_NO_DEVICE_ATTACHED implies that no
  *        devices have been found.
  */
 static LIBMTP_error_number_t get_mtp_usb_device_list(mtpdevice_list_t ** mtp_device_list)
 {
   ssize_t nrofdevs;
   libusb_device **devs = NULL;
   int ret, i;
+  LIBMTP_error_number_t init_usb_ret;
 
-  init_usb();
+  init_usb_ret = init_usb();
+  if (init_usb_ret != LIBMTP_ERROR_NONE)
+    return init_usb_ret;
 
   nrofdevs = libusb_get_device_list (NULL, &devs);
   for (i = 0; i < nrofdevs ; i++) {
       libusb_device *dev = devs[i];
       struct libusb_device_descriptor desc;
 
       ret = libusb_get_device_descriptor(dev, &desc);
       if (ret != LIBUSB_SUCCESS) continue;
 
       if (desc.bDeviceClass != LIBUSB_CLASS_HUB) {
@@ skipping 51 matching lines @@
  *
  * @param busno the bus number of the device to check
  * @param deviceno the device number of the device to check
  * @return 1 if the device is MTP else 0
  */
 int LIBMTP_Check_Specific_Device(int busno, int devno)
 {
   ssize_t nrofdevs;
   libusb_device **devs = NULL;
   int i;
+  LIBMTP_error_number_t init_usb_ret;
 
-  init_usb();
+  init_usb_ret = init_usb();
+  if (init_usb_ret != LIBMTP_ERROR_NONE)
+    return 0;
 
   nrofdevs = libusb_get_device_list (NULL, &devs);
   for (i = 0; i < nrofdevs ; i++ ) {
 
     if (libusb_get_bus_number(devs[i]) != busno)
       continue;
     if (libusb_get_device_address(devs[i]) != devno)
       continue;
 
       if (probe_device_descriptor(devs[i], NULL))
@@ skipping 1331 matching lines @@
                                            PTPParams *params,
                                            void **usbinfo)
 {
   PTP_USB *ptp_usb;
   libusb_device *ldevice;
   uint16_t ret = 0;
   int err, found = 0, i;
   ssize_t nrofdevs;
   libusb_device **devs = NULL;
   struct libusb_device_descriptor desc;
+  LIBMTP_error_number_t init_usb_ret;
 
   /* See if we can find this raw device again... */
-  init_usb();
+  init_usb_ret = init_usb();
+  if (init_usb_ret != LIBMTP_ERROR_NONE)
+    return init_usb_ret;
 
   nrofdevs = libusb_get_device_list (NULL, &devs);
   for (i = 0; i < nrofdevs ; i++) {
     if (libusb_get_bus_number (devs[i]) != device->bus_location)
       continue;
     if (libusb_get_device_address (devs[i]) != device->devnum)
       continue;
 
     ret = libusb_get_device_descriptor (devs[i], &desc);
     if (ret != LIBUSB_SUCCESS) continue;
@@ skipping 149 matching lines @@
 {
   return libusb_control_transfer(ptp_usb->handle,
                           LIBUSB_ENDPOINT_IN|LIBUSB_RECIPIENT_ENDPOINT,
                           LIBUSB_REQUEST_GET_STATUS,
                           USB_FEATURE_HALT,
                           ep,
                           (unsigned char *) status,
                           2,
                           ptp_usb->timeout);
 }