am edeed28b: am 4a280e3d: Merge "Don\'t use control requests to read device serial numbers."

    unsigned char ep_out;

};

/* True if name isn't a valid name for a USB device in /sys/bus/usb/devices.

 * Device names are made up of numbers, dots, and dashes, e.g., '7-1.5'.

 * We reject interfaces (e.g., '7-1.5:1.0') and host controllers (e.g. 'usb1').

 * The name must also start with a digit, to disallow '.' and '..'

 */

static inline int badname(const char *name)

{

    while(*name) {

        if(!isdigit(*name++)) return 1;

    if (!isdigit(*name))

      return 1;

    while(*++name) {

        if(!isdigit(*name) && *name != '.' && *name != '-')

            return 1;

    }

    return 0;

}

    return 0;

}

static int filter_usb_device(int fd, char *ptr, int len, int writable,

static int filter_usb_device(int fd, char* sysfs_name,

                             char *ptr, int len, int writable,

                             ifc_match_func callback,

                             int *ept_in_id, int *ept_out_id, int *ifc_id)

{

    info.dev_protocol = dev->bDeviceProtocol;

    info.writable = writable;

    // read device serial number (if there is one)

    info.serial_number[0] = 0;

    if (dev->iSerialNumber) {

        struct usbdevfs_ctrltransfer  ctrl;

        // Keep it short enough because some bootloaders are borked if the URB len is > 255

        // 128 is too big by 1.

        __u16 buffer[127];

        memset(buffer, 0, sizeof(buffer));

        ctrl.bRequestType = USB_DIR_IN|USB_TYPE_STANDARD|USB_RECIP_DEVICE;

        ctrl.bRequest = USB_REQ_GET_DESCRIPTOR;

        ctrl.wValue = (USB_DT_STRING << 8) | dev->iSerialNumber;

        //language ID (en-us) for serial number string

        ctrl.wIndex = 0x0409;

        ctrl.wLength = sizeof(buffer);

        ctrl.data = buffer;

        ctrl.timeout = 50;

        result = ioctl(fd, USBDEVFS_CONTROL, &ctrl);

        if (result > 0) {

            int i;

            // skip first word, and copy the rest to the serial string, changing shorts to bytes.

            result /= 2;

            for (i = 1; i < result; i++)

                info.serial_number[i - 1] = buffer[i];

            info.serial_number[i - 1] = 0;

        }

    }

    /* We need to get a path that represents a particular port on a particular

     * hub.  We are passed an fd that was obtained by opening an entry under

     * /dev/bus/usb.  Unfortunately, the names of those entries change each

     * time devices are plugged and unplugged.  So how to get a repeatable

     * path?  udevadm provided the inspiration.  We can get the major and

     * minor of the device file, read the symlink that can be found here:

     *   /sys/dev/char/<major>:<minor>

     * and then use the last element of that path.  As a concrete example, I

     * have an Android device at /dev/bus/usb/001/027 so working with bash:

     *   $ ls -l /dev/bus/usb/001/027

     *   crw-rw-r-- 1 root plugdev 189, 26 Apr  9 11:03 /dev/bus/usb/001/027

     *   $ ls -l /sys/dev/char/189:26

     *   lrwxrwxrwx 1 root root 0 Apr  9 11:03 /sys/dev/char/189:26 ->

     *           ../../devices/pci0000:00/0000:00:1a.7/usb1/1-4/1-4.2/1-4.2.3

     * So our device_path would be 1-4.2.3 which says my device is connected

     * to port 3 of a hub on port 2 of a hub on port 4 of bus 1 (per

     * http://www.linux-usb.org/FAQ.html).

    snprintf(info.device_path, sizeof(info.device_path), "usb:%s", sysfs_name);

    /* Read device serial number (if there is one).

     * We read the serial number from sysfs, since it's faster and more

     * reliable than issuing a control pipe read, and also won't

     * cause problems for devices which don't like getting descriptor

     * requests while they're in the middle of flashing.

     */

    info.device_path[0] = '\0';

    result = fstat(fd, &st);

    if (!result && S_ISCHR(st.st_mode)) {

        char cdev[128];

        char link[256];

        char *slash;

        ssize_t link_len;

        snprintf(cdev, sizeof(cdev), "/sys/dev/char/%d:%d",

                 major(st.st_rdev), minor(st.st_rdev));

        link_len = readlink(cdev, link, sizeof(link) - 1);

        if (link_len > 0) {

            link[link_len] = '\0';

            slash = strrchr(link, '/');

            if (slash)

                snprintf(info.device_path, sizeof(info.device_path), "usb:%s", slash+1);

    info.serial_number[0] = '\0';

    if (dev->iSerialNumber) {

        char path[80];

        int fd;

        snprintf(path, sizeof(path),

                 "/sys/bus/usb/devices/%s/serial", sysfs_name);

        path[sizeof(path) - 1] = '\0';

        fd = open(path, O_RDONLY);

        if (fd >= 0) {

            int chars_read = read(fd, info.serial_number,

                                  sizeof(info.serial_number) - 1);

            close(fd);

            if (chars_read <= 0)

                info.serial_number[0] = '\0';

            else if (info.serial_number[chars_read - 1] == '\n') {

                // strip trailing newline

                info.serial_number[chars_read - 1] = '\0';

            }

        }

    }

    return -1;

}

static int read_sysfs_string(const char *sysfs_name, const char *sysfs_node,

                             char* buf, int bufsize)

{

    char path[80];

    int fd, n;

    snprintf(path, sizeof(path),

             "/sys/bus/usb/devices/%s/%s", sysfs_name, sysfs_node);

    path[sizeof(path) - 1] = '\0';

    fd = open(path, O_RDONLY);

    if (fd < 0)

        return -1;

    n = read(fd, buf, bufsize - 1);

    close(fd);

    if (n < 0)

        return -1;

    buf[n] = '\0';

    return n;

}

static int read_sysfs_number(const char *sysfs_name, const char *sysfs_node)

{

    char buf[16];

    int value;

    if (read_sysfs_string(sysfs_name, sysfs_node, buf, sizeof(buf)) < 0)

        return -1;

    if (sscanf(buf, "%d", &value) != 1)

        return -1;

    return value;

}

/* Given the name of a USB device in sysfs, get the name for the same

 * device in devfs. Returns 0 for success, -1 for failure.

 */

static int convert_to_devfs_name(const char* sysfs_name,

                                 char* devname, int devname_size)

{

    int busnum, devnum;

    busnum = read_sysfs_number(sysfs_name, "busnum");

    if (busnum < 0)

        return -1;

    devnum = read_sysfs_number(sysfs_name, "devnum");

    if (devnum < 0)

        return -1;

    snprintf(devname, devname_size, "/dev/bus/usb/%03d/%03d", busnum, devnum);

    return 0;

}

static usb_handle *find_usb_device(const char *base, ifc_match_func callback)

{

    usb_handle *usb = 0;

    char busname[64], devname[64];

    char devname[64];

    char desc[1024];

    int n, in, out, ifc;

    DIR *busdir, *devdir;

    DIR *busdir;

    struct dirent *de;

    int fd;

    int writable;

    while((de = readdir(busdir)) && (usb == 0)) {

        if(badname(de->d_name)) continue;

        sprintf(busname, "%s/%s", base, de->d_name);

        devdir = opendir(busname);

        if(devdir == 0) continue;

//        DBG("[ scanning %s ]\n", busname);

        while((de = readdir(devdir)) && (usb == 0)) {

            if(badname(de->d_name)) continue;

            sprintf(devname, "%s/%s", busname, de->d_name);

        if(!convert_to_devfs_name(de->d_name, devname, sizeof(devname))) {

//            DBG("[ scanning %s ]\n", devname);

            writable = 1;

            n = read(fd, desc, sizeof(desc));

            if(filter_usb_device(fd, desc, n, writable, callback,

            if(filter_usb_device(fd, de->d_name, desc, n, writable, callback,

                                 &in, &out, &ifc) == 0) {

                usb = calloc(1, sizeof(usb_handle));

                strcpy(usb->fname, devname);

                close(fd);

            }

        }

        closedir(devdir);

    }

    closedir(busdir);

usb_handle *usb_open(ifc_match_func callback)

{

    return find_usb_device("/dev/bus/usb", callback);

    return find_usb_device("/sys/bus/usb/devices", callback);

}