1194 lines
35 KiB
C
1194 lines
35 KiB
C
/* -*- Mode: C; indent-tabs-mode:t ; c-basic-offset:8 -*- */
|
|
/*
|
|
* USB descriptor handling functions for libusb
|
|
* Copyright © 2007 Daniel Drake <dsd@gentoo.org>
|
|
* Copyright © 2001 Johannes Erdfelt <johannes@erdfelt.com>
|
|
*
|
|
* This library is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2.1 of the License, or (at your option) any later version.
|
|
*
|
|
* This library is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with this library; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
|
|
#include <config.h>
|
|
|
|
#include <errno.h>
|
|
#include <stdint.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
|
|
#include "libusbi.h"
|
|
|
|
#define DESC_HEADER_LENGTH 2
|
|
#define DEVICE_DESC_LENGTH 18
|
|
#define CONFIG_DESC_LENGTH 9
|
|
#define INTERFACE_DESC_LENGTH 9
|
|
#define ENDPOINT_DESC_LENGTH 7
|
|
#define ENDPOINT_AUDIO_DESC_LENGTH 9
|
|
|
|
/** @defgroup libusb_desc USB descriptors
|
|
* This page details how to examine the various standard USB descriptors
|
|
* for detected devices
|
|
*/
|
|
|
|
/* set host_endian if the w values are already in host endian format,
|
|
* as opposed to bus endian. */
|
|
int usbi_parse_descriptor(const unsigned char *source, const char *descriptor,
|
|
void *dest, int host_endian)
|
|
{
|
|
const unsigned char *sp = source;
|
|
unsigned char *dp = dest;
|
|
uint16_t w;
|
|
const char *cp;
|
|
uint32_t d;
|
|
|
|
for (cp = descriptor; *cp; cp++) {
|
|
switch (*cp) {
|
|
case 'b': /* 8-bit byte */
|
|
*dp++ = *sp++;
|
|
break;
|
|
case 'w': /* 16-bit word, convert from little endian to CPU */
|
|
dp += ((uintptr_t)dp & 1); /* Align to word boundary */
|
|
|
|
if (host_endian) {
|
|
memcpy(dp, sp, 2);
|
|
} else {
|
|
w = (uint16_t)((sp[1] << 8) | sp[0]);
|
|
*((uint16_t *)dp) = w;
|
|
}
|
|
sp += 2;
|
|
dp += 2;
|
|
break;
|
|
case 'd': /* 32-bit word, convert from little endian to CPU */
|
|
dp += ((uintptr_t)dp & 1); /* Align to word boundary */
|
|
|
|
if (host_endian) {
|
|
memcpy(dp, sp, 4);
|
|
} else {
|
|
d = (uint32_t)((sp[3] << 24) | (sp[2] << 16) |
|
|
(sp[1] << 8) | sp[0]);
|
|
*((uint32_t *)dp) = d;
|
|
}
|
|
sp += 4;
|
|
dp += 4;
|
|
break;
|
|
case 'u': /* 16 byte UUID */
|
|
memcpy(dp, sp, 16);
|
|
sp += 16;
|
|
dp += 16;
|
|
break;
|
|
}
|
|
}
|
|
|
|
return (int) (sp - source);
|
|
}
|
|
|
|
static void clear_endpoint(struct libusb_endpoint_descriptor *endpoint)
|
|
{
|
|
free((void *) endpoint->extra);
|
|
}
|
|
|
|
static int parse_endpoint(struct libusb_context *ctx,
|
|
struct libusb_endpoint_descriptor *endpoint, unsigned char *buffer,
|
|
int size, int host_endian)
|
|
{
|
|
struct usb_descriptor_header header;
|
|
unsigned char *extra;
|
|
unsigned char *begin;
|
|
int parsed = 0;
|
|
int len;
|
|
|
|
if (size < DESC_HEADER_LENGTH) {
|
|
usbi_err(ctx, "short endpoint descriptor read %d/%d",
|
|
size, DESC_HEADER_LENGTH);
|
|
return LIBUSB_ERROR_IO;
|
|
}
|
|
|
|
usbi_parse_descriptor(buffer, "bb", &header, 0);
|
|
if (header.bDescriptorType != LIBUSB_DT_ENDPOINT) {
|
|
usbi_err(ctx, "unexpected descriptor %x (expected %x)",
|
|
header.bDescriptorType, LIBUSB_DT_ENDPOINT);
|
|
return parsed;
|
|
}
|
|
if (header.bLength > size) {
|
|
usbi_warn(ctx, "short endpoint descriptor read %d/%d",
|
|
size, header.bLength);
|
|
return parsed;
|
|
}
|
|
if (header.bLength >= ENDPOINT_AUDIO_DESC_LENGTH)
|
|
usbi_parse_descriptor(buffer, "bbbbwbbb", endpoint, host_endian);
|
|
else if (header.bLength >= ENDPOINT_DESC_LENGTH)
|
|
usbi_parse_descriptor(buffer, "bbbbwb", endpoint, host_endian);
|
|
else {
|
|
usbi_err(ctx, "invalid endpoint bLength (%d)", header.bLength);
|
|
return LIBUSB_ERROR_IO;
|
|
}
|
|
|
|
buffer += header.bLength;
|
|
size -= header.bLength;
|
|
parsed += header.bLength;
|
|
|
|
/* Skip over the rest of the Class Specific or Vendor Specific */
|
|
/* descriptors */
|
|
begin = buffer;
|
|
while (size >= DESC_HEADER_LENGTH) {
|
|
usbi_parse_descriptor(buffer, "bb", &header, 0);
|
|
if (header.bLength < DESC_HEADER_LENGTH) {
|
|
usbi_err(ctx, "invalid extra ep desc len (%d)",
|
|
header.bLength);
|
|
return LIBUSB_ERROR_IO;
|
|
} else if (header.bLength > size) {
|
|
usbi_warn(ctx, "short extra ep desc read %d/%d",
|
|
size, header.bLength);
|
|
return parsed;
|
|
}
|
|
|
|
/* If we find another "proper" descriptor then we're done */
|
|
if ((header.bDescriptorType == LIBUSB_DT_ENDPOINT) ||
|
|
(header.bDescriptorType == LIBUSB_DT_INTERFACE) ||
|
|
(header.bDescriptorType == LIBUSB_DT_CONFIG) ||
|
|
(header.bDescriptorType == LIBUSB_DT_DEVICE))
|
|
break;
|
|
|
|
usbi_dbg("skipping descriptor %x", header.bDescriptorType);
|
|
buffer += header.bLength;
|
|
size -= header.bLength;
|
|
parsed += header.bLength;
|
|
}
|
|
|
|
/* Copy any unknown descriptors into a storage area for drivers */
|
|
/* to later parse */
|
|
len = (int)(buffer - begin);
|
|
if (len <= 0) {
|
|
endpoint->extra = NULL;
|
|
endpoint->extra_length = 0;
|
|
return parsed;
|
|
}
|
|
|
|
extra = malloc((size_t)len);
|
|
endpoint->extra = extra;
|
|
if (!extra) {
|
|
endpoint->extra_length = 0;
|
|
return LIBUSB_ERROR_NO_MEM;
|
|
}
|
|
|
|
memcpy(extra, begin, len);
|
|
endpoint->extra_length = len;
|
|
|
|
return parsed;
|
|
}
|
|
|
|
static void clear_interface(struct libusb_interface *usb_interface)
|
|
{
|
|
int i;
|
|
int j;
|
|
|
|
if (usb_interface->altsetting) {
|
|
for (i = 0; i < usb_interface->num_altsetting; i++) {
|
|
struct libusb_interface_descriptor *ifp =
|
|
(struct libusb_interface_descriptor *)
|
|
usb_interface->altsetting + i;
|
|
free((void *) ifp->extra);
|
|
if (ifp->endpoint) {
|
|
for (j = 0; j < ifp->bNumEndpoints; j++)
|
|
clear_endpoint((struct libusb_endpoint_descriptor *)
|
|
ifp->endpoint + j);
|
|
}
|
|
free((void *) ifp->endpoint);
|
|
}
|
|
}
|
|
free((void *) usb_interface->altsetting);
|
|
usb_interface->altsetting = NULL;
|
|
}
|
|
|
|
static int parse_interface(libusb_context *ctx,
|
|
struct libusb_interface *usb_interface, unsigned char *buffer, int size,
|
|
int host_endian)
|
|
{
|
|
int i;
|
|
int len;
|
|
int r;
|
|
int parsed = 0;
|
|
int interface_number = -1;
|
|
struct usb_descriptor_header header;
|
|
struct libusb_interface_descriptor *ifp;
|
|
unsigned char *begin;
|
|
|
|
usb_interface->num_altsetting = 0;
|
|
|
|
while (size >= INTERFACE_DESC_LENGTH) {
|
|
struct libusb_interface_descriptor *altsetting =
|
|
(struct libusb_interface_descriptor *) usb_interface->altsetting;
|
|
altsetting = usbi_reallocf(altsetting,
|
|
sizeof(struct libusb_interface_descriptor) *
|
|
((size_t)usb_interface->num_altsetting + 1));
|
|
if (!altsetting) {
|
|
r = LIBUSB_ERROR_NO_MEM;
|
|
goto err;
|
|
}
|
|
usb_interface->altsetting = altsetting;
|
|
|
|
ifp = altsetting + usb_interface->num_altsetting;
|
|
usbi_parse_descriptor(buffer, "bbbbbbbbb", ifp, 0);
|
|
if (ifp->bDescriptorType != LIBUSB_DT_INTERFACE) {
|
|
usbi_err(ctx, "unexpected descriptor %x (expected %x)",
|
|
ifp->bDescriptorType, LIBUSB_DT_INTERFACE);
|
|
return parsed;
|
|
}
|
|
if (ifp->bLength < INTERFACE_DESC_LENGTH) {
|
|
usbi_err(ctx, "invalid interface bLength (%d)",
|
|
ifp->bLength);
|
|
r = LIBUSB_ERROR_IO;
|
|
goto err;
|
|
}
|
|
if (ifp->bLength > size) {
|
|
usbi_warn(ctx, "short intf descriptor read %d/%d",
|
|
size, ifp->bLength);
|
|
return parsed;
|
|
}
|
|
if (ifp->bNumEndpoints > USB_MAXENDPOINTS) {
|
|
usbi_err(ctx, "too many endpoints (%d)", ifp->bNumEndpoints);
|
|
r = LIBUSB_ERROR_IO;
|
|
goto err;
|
|
}
|
|
|
|
usb_interface->num_altsetting++;
|
|
ifp->extra = NULL;
|
|
ifp->extra_length = 0;
|
|
ifp->endpoint = NULL;
|
|
|
|
if (interface_number == -1)
|
|
interface_number = ifp->bInterfaceNumber;
|
|
|
|
/* Skip over the interface */
|
|
buffer += ifp->bLength;
|
|
parsed += ifp->bLength;
|
|
size -= ifp->bLength;
|
|
|
|
begin = buffer;
|
|
|
|
/* Skip over any interface, class or vendor descriptors */
|
|
while (size >= DESC_HEADER_LENGTH) {
|
|
usbi_parse_descriptor(buffer, "bb", &header, 0);
|
|
if (header.bLength < DESC_HEADER_LENGTH) {
|
|
usbi_err(ctx,
|
|
"invalid extra intf desc len (%d)",
|
|
header.bLength);
|
|
r = LIBUSB_ERROR_IO;
|
|
goto err;
|
|
} else if (header.bLength > size) {
|
|
usbi_warn(ctx,
|
|
"short extra intf desc read %d/%d",
|
|
size, header.bLength);
|
|
return parsed;
|
|
}
|
|
|
|
/* If we find another "proper" descriptor then we're done */
|
|
if ((header.bDescriptorType == LIBUSB_DT_INTERFACE) ||
|
|
(header.bDescriptorType == LIBUSB_DT_ENDPOINT) ||
|
|
(header.bDescriptorType == LIBUSB_DT_CONFIG) ||
|
|
(header.bDescriptorType == LIBUSB_DT_DEVICE))
|
|
break;
|
|
|
|
buffer += header.bLength;
|
|
parsed += header.bLength;
|
|
size -= header.bLength;
|
|
}
|
|
|
|
/* Copy any unknown descriptors into a storage area for */
|
|
/* drivers to later parse */
|
|
len = (int)(buffer - begin);
|
|
if (len > 0) {
|
|
ifp->extra = malloc((size_t)len);
|
|
if (!ifp->extra) {
|
|
r = LIBUSB_ERROR_NO_MEM;
|
|
goto err;
|
|
}
|
|
memcpy((unsigned char *) ifp->extra, begin, len);
|
|
ifp->extra_length = len;
|
|
}
|
|
|
|
if (ifp->bNumEndpoints > 0) {
|
|
struct libusb_endpoint_descriptor *endpoint;
|
|
endpoint = calloc(ifp->bNumEndpoints, sizeof(struct libusb_endpoint_descriptor));
|
|
ifp->endpoint = endpoint;
|
|
if (!endpoint) {
|
|
r = LIBUSB_ERROR_NO_MEM;
|
|
goto err;
|
|
}
|
|
|
|
for (i = 0; i < ifp->bNumEndpoints; i++) {
|
|
r = parse_endpoint(ctx, endpoint + i, buffer, size,
|
|
host_endian);
|
|
if (r < 0)
|
|
goto err;
|
|
if (r == 0) {
|
|
ifp->bNumEndpoints = (uint8_t)i;
|
|
break;
|
|
}
|
|
|
|
buffer += r;
|
|
parsed += r;
|
|
size -= r;
|
|
}
|
|
}
|
|
|
|
/* We check to see if it's an alternate to this one */
|
|
ifp = (struct libusb_interface_descriptor *) buffer;
|
|
if (size < LIBUSB_DT_INTERFACE_SIZE ||
|
|
ifp->bDescriptorType != LIBUSB_DT_INTERFACE ||
|
|
ifp->bInterfaceNumber != interface_number)
|
|
return parsed;
|
|
}
|
|
|
|
return parsed;
|
|
err:
|
|
clear_interface(usb_interface);
|
|
return r;
|
|
}
|
|
|
|
static void clear_configuration(struct libusb_config_descriptor *config)
|
|
{
|
|
int i;
|
|
if (config->interface) {
|
|
for (i = 0; i < config->bNumInterfaces; i++)
|
|
clear_interface((struct libusb_interface *)
|
|
config->interface + i);
|
|
}
|
|
free((void *) config->interface);
|
|
free((void *) config->extra);
|
|
}
|
|
|
|
static int parse_configuration(struct libusb_context *ctx,
|
|
struct libusb_config_descriptor *config, unsigned char *buffer,
|
|
int size, int host_endian)
|
|
{
|
|
int i;
|
|
int r;
|
|
struct usb_descriptor_header header;
|
|
struct libusb_interface *usb_interface;
|
|
|
|
if (size < LIBUSB_DT_CONFIG_SIZE) {
|
|
usbi_err(ctx, "short config descriptor read %d/%d",
|
|
size, LIBUSB_DT_CONFIG_SIZE);
|
|
return LIBUSB_ERROR_IO;
|
|
}
|
|
|
|
usbi_parse_descriptor(buffer, "bbwbbbbb", config, host_endian);
|
|
if (config->bDescriptorType != LIBUSB_DT_CONFIG) {
|
|
usbi_err(ctx, "unexpected descriptor %x (expected %x)",
|
|
config->bDescriptorType, LIBUSB_DT_CONFIG);
|
|
return LIBUSB_ERROR_IO;
|
|
}
|
|
if (config->bLength < LIBUSB_DT_CONFIG_SIZE) {
|
|
usbi_err(ctx, "invalid config bLength (%d)", config->bLength);
|
|
return LIBUSB_ERROR_IO;
|
|
}
|
|
if (config->bLength > size) {
|
|
usbi_err(ctx, "short config descriptor read %d/%d",
|
|
size, config->bLength);
|
|
return LIBUSB_ERROR_IO;
|
|
}
|
|
if (config->bNumInterfaces > USB_MAXINTERFACES) {
|
|
usbi_err(ctx, "too many interfaces (%d)", config->bNumInterfaces);
|
|
return LIBUSB_ERROR_IO;
|
|
}
|
|
|
|
usb_interface = calloc(config->bNumInterfaces, sizeof(struct libusb_interface));
|
|
config->interface = usb_interface;
|
|
if (!usb_interface)
|
|
return LIBUSB_ERROR_NO_MEM;
|
|
|
|
buffer += config->bLength;
|
|
size -= config->bLength;
|
|
|
|
config->extra = NULL;
|
|
config->extra_length = 0;
|
|
|
|
for (i = 0; i < config->bNumInterfaces; i++) {
|
|
int len;
|
|
unsigned char *begin;
|
|
|
|
/* Skip over the rest of the Class Specific or Vendor */
|
|
/* Specific descriptors */
|
|
begin = buffer;
|
|
while (size >= DESC_HEADER_LENGTH) {
|
|
usbi_parse_descriptor(buffer, "bb", &header, 0);
|
|
|
|
if (header.bLength < DESC_HEADER_LENGTH) {
|
|
usbi_err(ctx,
|
|
"invalid extra config desc len (%d)",
|
|
header.bLength);
|
|
r = LIBUSB_ERROR_IO;
|
|
goto err;
|
|
} else if (header.bLength > size) {
|
|
usbi_warn(ctx,
|
|
"short extra config desc read %d/%d",
|
|
size, header.bLength);
|
|
config->bNumInterfaces = (uint8_t)i;
|
|
return size;
|
|
}
|
|
|
|
/* If we find another "proper" descriptor then we're done */
|
|
if ((header.bDescriptorType == LIBUSB_DT_ENDPOINT) ||
|
|
(header.bDescriptorType == LIBUSB_DT_INTERFACE) ||
|
|
(header.bDescriptorType == LIBUSB_DT_CONFIG) ||
|
|
(header.bDescriptorType == LIBUSB_DT_DEVICE))
|
|
break;
|
|
|
|
usbi_dbg("skipping descriptor 0x%x", header.bDescriptorType);
|
|
buffer += header.bLength;
|
|
size -= header.bLength;
|
|
}
|
|
|
|
/* Copy any unknown descriptors into a storage area for */
|
|
/* drivers to later parse */
|
|
len = (int)(buffer - begin);
|
|
if (len > 0) {
|
|
/* FIXME: We should realloc and append here */
|
|
if (!config->extra_length) {
|
|
config->extra = malloc((size_t)len);
|
|
if (!config->extra) {
|
|
r = LIBUSB_ERROR_NO_MEM;
|
|
goto err;
|
|
}
|
|
|
|
memcpy((unsigned char *) config->extra, begin, len);
|
|
config->extra_length = len;
|
|
}
|
|
}
|
|
|
|
r = parse_interface(ctx, usb_interface + i, buffer, size, host_endian);
|
|
if (r < 0)
|
|
goto err;
|
|
if (r == 0) {
|
|
config->bNumInterfaces = (uint8_t)i;
|
|
break;
|
|
}
|
|
|
|
buffer += r;
|
|
size -= r;
|
|
}
|
|
|
|
return size;
|
|
|
|
err:
|
|
clear_configuration(config);
|
|
return r;
|
|
}
|
|
|
|
static int raw_desc_to_config(struct libusb_context *ctx,
|
|
unsigned char *buf, int size, int host_endian,
|
|
struct libusb_config_descriptor **config)
|
|
{
|
|
struct libusb_config_descriptor *_config = malloc(sizeof(*_config));
|
|
int r;
|
|
|
|
if (!_config)
|
|
return LIBUSB_ERROR_NO_MEM;
|
|
|
|
r = parse_configuration(ctx, _config, buf, size, host_endian);
|
|
if (r < 0) {
|
|
usbi_err(ctx, "parse_configuration failed with error %d", r);
|
|
free(_config);
|
|
return r;
|
|
} else if (r > 0) {
|
|
usbi_warn(ctx, "still %d bytes of descriptor data left", r);
|
|
}
|
|
|
|
*config = _config;
|
|
return LIBUSB_SUCCESS;
|
|
}
|
|
|
|
int usbi_device_cache_descriptor(libusb_device *dev)
|
|
{
|
|
int r, host_endian = 0;
|
|
|
|
r = usbi_backend.get_device_descriptor(dev, (unsigned char *) &dev->device_descriptor,
|
|
&host_endian);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
if (!host_endian) {
|
|
dev->device_descriptor.bcdUSB = libusb_le16_to_cpu(dev->device_descriptor.bcdUSB);
|
|
dev->device_descriptor.idVendor = libusb_le16_to_cpu(dev->device_descriptor.idVendor);
|
|
dev->device_descriptor.idProduct = libusb_le16_to_cpu(dev->device_descriptor.idProduct);
|
|
dev->device_descriptor.bcdDevice = libusb_le16_to_cpu(dev->device_descriptor.bcdDevice);
|
|
}
|
|
|
|
return LIBUSB_SUCCESS;
|
|
}
|
|
|
|
/** \ingroup libusb_desc
|
|
* Get the USB device descriptor for a given device.
|
|
*
|
|
* This is a non-blocking function; the device descriptor is cached in memory.
|
|
*
|
|
* Note since libusb-1.0.16, \ref LIBUSB_API_VERSION >= 0x01000102, this
|
|
* function always succeeds.
|
|
*
|
|
* \param dev the device
|
|
* \param desc output location for the descriptor data
|
|
* \returns 0 on success or a LIBUSB_ERROR code on failure
|
|
*/
|
|
int API_EXPORTED libusb_get_device_descriptor(libusb_device *dev,
|
|
struct libusb_device_descriptor *desc)
|
|
{
|
|
usbi_dbg("");
|
|
memcpy((unsigned char *) desc, (unsigned char *) &dev->device_descriptor,
|
|
sizeof (dev->device_descriptor));
|
|
return 0;
|
|
}
|
|
|
|
/** \ingroup libusb_desc
|
|
* Get the USB configuration descriptor for the currently active configuration.
|
|
* This is a non-blocking function which does not involve any requests being
|
|
* sent to the device.
|
|
*
|
|
* \param dev a device
|
|
* \param config output location for the USB configuration descriptor. Only
|
|
* valid if 0 was returned. Must be freed with libusb_free_config_descriptor()
|
|
* after use.
|
|
* \returns 0 on success
|
|
* \returns LIBUSB_ERROR_NOT_FOUND if the device is in unconfigured state
|
|
* \returns another LIBUSB_ERROR code on error
|
|
* \see libusb_get_config_descriptor
|
|
*/
|
|
int API_EXPORTED libusb_get_active_config_descriptor(libusb_device *dev,
|
|
struct libusb_config_descriptor **config)
|
|
{
|
|
struct libusb_config_descriptor _config;
|
|
unsigned char tmp[LIBUSB_DT_CONFIG_SIZE];
|
|
unsigned char *buf = NULL;
|
|
int host_endian = 0;
|
|
int r;
|
|
|
|
r = usbi_backend.get_active_config_descriptor(dev, tmp,
|
|
LIBUSB_DT_CONFIG_SIZE, &host_endian);
|
|
if (r < 0)
|
|
return r;
|
|
if (r < LIBUSB_DT_CONFIG_SIZE) {
|
|
usbi_err(dev->ctx, "short config descriptor read %d/%d",
|
|
r, LIBUSB_DT_CONFIG_SIZE);
|
|
return LIBUSB_ERROR_IO;
|
|
}
|
|
|
|
usbi_parse_descriptor(tmp, "bbw", &_config, host_endian);
|
|
buf = malloc(_config.wTotalLength);
|
|
if (!buf)
|
|
return LIBUSB_ERROR_NO_MEM;
|
|
|
|
r = usbi_backend.get_active_config_descriptor(dev, buf,
|
|
_config.wTotalLength, &host_endian);
|
|
if (r >= 0)
|
|
r = raw_desc_to_config(dev->ctx, buf, r, host_endian, config);
|
|
|
|
free(buf);
|
|
return r;
|
|
}
|
|
|
|
/** \ingroup libusb_desc
|
|
* Get a USB configuration descriptor based on its index.
|
|
* This is a non-blocking function which does not involve any requests being
|
|
* sent to the device.
|
|
*
|
|
* \param dev a device
|
|
* \param config_index the index of the configuration you wish to retrieve
|
|
* \param config output location for the USB configuration descriptor. Only
|
|
* valid if 0 was returned. Must be freed with libusb_free_config_descriptor()
|
|
* after use.
|
|
* \returns 0 on success
|
|
* \returns LIBUSB_ERROR_NOT_FOUND if the configuration does not exist
|
|
* \returns another LIBUSB_ERROR code on error
|
|
* \see libusb_get_active_config_descriptor()
|
|
* \see libusb_get_config_descriptor_by_value()
|
|
*/
|
|
int API_EXPORTED libusb_get_config_descriptor(libusb_device *dev,
|
|
uint8_t config_index, struct libusb_config_descriptor **config)
|
|
{
|
|
struct libusb_config_descriptor _config;
|
|
unsigned char tmp[LIBUSB_DT_CONFIG_SIZE];
|
|
unsigned char *buf = NULL;
|
|
int host_endian = 0;
|
|
int r;
|
|
|
|
usbi_dbg("index %d", config_index);
|
|
if (config_index >= dev->num_configurations)
|
|
return LIBUSB_ERROR_NOT_FOUND;
|
|
|
|
r = usbi_backend.get_config_descriptor(dev, config_index, tmp,
|
|
LIBUSB_DT_CONFIG_SIZE, &host_endian);
|
|
if (r < 0)
|
|
return r;
|
|
if (r < LIBUSB_DT_CONFIG_SIZE) {
|
|
usbi_err(dev->ctx, "short config descriptor read %d/%d",
|
|
r, LIBUSB_DT_CONFIG_SIZE);
|
|
return LIBUSB_ERROR_IO;
|
|
}
|
|
|
|
usbi_parse_descriptor(tmp, "bbw", &_config, host_endian);
|
|
buf = malloc(_config.wTotalLength);
|
|
if (!buf)
|
|
return LIBUSB_ERROR_NO_MEM;
|
|
|
|
r = usbi_backend.get_config_descriptor(dev, config_index, buf,
|
|
_config.wTotalLength, &host_endian);
|
|
if (r >= 0)
|
|
r = raw_desc_to_config(dev->ctx, buf, r, host_endian, config);
|
|
|
|
free(buf);
|
|
return r;
|
|
}
|
|
|
|
/* iterate through all configurations, returning the index of the configuration
|
|
* matching a specific bConfigurationValue in the idx output parameter, or -1
|
|
* if the config was not found.
|
|
* returns 0 on success or a LIBUSB_ERROR code
|
|
*/
|
|
int usbi_get_config_index_by_value(struct libusb_device *dev,
|
|
uint8_t bConfigurationValue, int *idx)
|
|
{
|
|
uint8_t i;
|
|
|
|
usbi_dbg("value %d", bConfigurationValue);
|
|
for (i = 0; i < dev->num_configurations; i++) {
|
|
unsigned char tmp[6];
|
|
int host_endian;
|
|
int r = usbi_backend.get_config_descriptor(dev, i, tmp, sizeof(tmp),
|
|
&host_endian);
|
|
if (r < 0) {
|
|
*idx = -1;
|
|
return r;
|
|
}
|
|
if (tmp[5] == bConfigurationValue) {
|
|
*idx = i;
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
*idx = -1;
|
|
return 0;
|
|
}
|
|
|
|
/** \ingroup libusb_desc
|
|
* Get a USB configuration descriptor with a specific bConfigurationValue.
|
|
* This is a non-blocking function which does not involve any requests being
|
|
* sent to the device.
|
|
*
|
|
* \param dev a device
|
|
* \param bConfigurationValue the bConfigurationValue of the configuration you
|
|
* wish to retrieve
|
|
* \param config output location for the USB configuration descriptor. Only
|
|
* valid if 0 was returned. Must be freed with libusb_free_config_descriptor()
|
|
* after use.
|
|
* \returns 0 on success
|
|
* \returns LIBUSB_ERROR_NOT_FOUND if the configuration does not exist
|
|
* \returns another LIBUSB_ERROR code on error
|
|
* \see libusb_get_active_config_descriptor()
|
|
* \see libusb_get_config_descriptor()
|
|
*/
|
|
int API_EXPORTED libusb_get_config_descriptor_by_value(libusb_device *dev,
|
|
uint8_t bConfigurationValue, struct libusb_config_descriptor **config)
|
|
{
|
|
int r, idx, host_endian;
|
|
unsigned char *buf = NULL;
|
|
|
|
if (usbi_backend.get_config_descriptor_by_value) {
|
|
r = usbi_backend.get_config_descriptor_by_value(dev,
|
|
bConfigurationValue, &buf, &host_endian);
|
|
if (r < 0)
|
|
return r;
|
|
return raw_desc_to_config(dev->ctx, buf, r, host_endian, config);
|
|
}
|
|
|
|
r = usbi_get_config_index_by_value(dev, bConfigurationValue, &idx);
|
|
if (r < 0)
|
|
return r;
|
|
else if (idx == -1)
|
|
return LIBUSB_ERROR_NOT_FOUND;
|
|
else
|
|
return libusb_get_config_descriptor(dev, (uint8_t) idx, config);
|
|
}
|
|
|
|
/** \ingroup libusb_desc
|
|
* Free a configuration descriptor obtained from
|
|
* libusb_get_active_config_descriptor() or libusb_get_config_descriptor().
|
|
* It is safe to call this function with a NULL config parameter, in which
|
|
* case the function simply returns.
|
|
*
|
|
* \param config the configuration descriptor to free
|
|
*/
|
|
void API_EXPORTED libusb_free_config_descriptor(
|
|
struct libusb_config_descriptor *config)
|
|
{
|
|
if (!config)
|
|
return;
|
|
|
|
clear_configuration(config);
|
|
free(config);
|
|
}
|
|
|
|
/** \ingroup libusb_desc
|
|
* Get an endpoints superspeed endpoint companion descriptor (if any)
|
|
*
|
|
* \param ctx the context to operate on, or NULL for the default context
|
|
* \param endpoint endpoint descriptor from which to get the superspeed
|
|
* endpoint companion descriptor
|
|
* \param ep_comp output location for the superspeed endpoint companion
|
|
* descriptor. Only valid if 0 was returned. Must be freed with
|
|
* libusb_free_ss_endpoint_companion_descriptor() after use.
|
|
* \returns 0 on success
|
|
* \returns LIBUSB_ERROR_NOT_FOUND if the configuration does not exist
|
|
* \returns another LIBUSB_ERROR code on error
|
|
*/
|
|
int API_EXPORTED libusb_get_ss_endpoint_companion_descriptor(
|
|
struct libusb_context *ctx,
|
|
const struct libusb_endpoint_descriptor *endpoint,
|
|
struct libusb_ss_endpoint_companion_descriptor **ep_comp)
|
|
{
|
|
struct usb_descriptor_header header;
|
|
int size = endpoint->extra_length;
|
|
const unsigned char *buffer = endpoint->extra;
|
|
|
|
*ep_comp = NULL;
|
|
|
|
while (size >= DESC_HEADER_LENGTH) {
|
|
usbi_parse_descriptor(buffer, "bb", &header, 0);
|
|
if (header.bLength < 2 || header.bLength > size) {
|
|
usbi_err(ctx, "invalid descriptor length %d",
|
|
header.bLength);
|
|
return LIBUSB_ERROR_IO;
|
|
}
|
|
if (header.bDescriptorType != LIBUSB_DT_SS_ENDPOINT_COMPANION) {
|
|
buffer += header.bLength;
|
|
size -= header.bLength;
|
|
continue;
|
|
}
|
|
if (header.bLength < LIBUSB_DT_SS_ENDPOINT_COMPANION_SIZE) {
|
|
usbi_err(ctx, "invalid ss-ep-comp-desc length %d",
|
|
header.bLength);
|
|
return LIBUSB_ERROR_IO;
|
|
}
|
|
*ep_comp = malloc(sizeof(**ep_comp));
|
|
if (*ep_comp == NULL)
|
|
return LIBUSB_ERROR_NO_MEM;
|
|
usbi_parse_descriptor(buffer, "bbbbw", *ep_comp, 0);
|
|
return LIBUSB_SUCCESS;
|
|
}
|
|
return LIBUSB_ERROR_NOT_FOUND;
|
|
}
|
|
|
|
/** \ingroup libusb_desc
|
|
* Free a superspeed endpoint companion descriptor obtained from
|
|
* libusb_get_ss_endpoint_companion_descriptor().
|
|
* It is safe to call this function with a NULL ep_comp parameter, in which
|
|
* case the function simply returns.
|
|
*
|
|
* \param ep_comp the superspeed endpoint companion descriptor to free
|
|
*/
|
|
void API_EXPORTED libusb_free_ss_endpoint_companion_descriptor(
|
|
struct libusb_ss_endpoint_companion_descriptor *ep_comp)
|
|
{
|
|
free(ep_comp);
|
|
}
|
|
|
|
static int parse_bos(struct libusb_context *ctx,
|
|
struct libusb_bos_descriptor **bos,
|
|
unsigned char *buffer, int size, int host_endian)
|
|
{
|
|
struct libusb_bos_descriptor bos_header, *_bos;
|
|
struct libusb_bos_dev_capability_descriptor dev_cap;
|
|
int i;
|
|
|
|
if (size < LIBUSB_DT_BOS_SIZE) {
|
|
usbi_err(ctx, "short bos descriptor read %d/%d",
|
|
size, LIBUSB_DT_BOS_SIZE);
|
|
return LIBUSB_ERROR_IO;
|
|
}
|
|
|
|
usbi_parse_descriptor(buffer, "bbwb", &bos_header, host_endian);
|
|
if (bos_header.bDescriptorType != LIBUSB_DT_BOS) {
|
|
usbi_err(ctx, "unexpected descriptor %x (expected %x)",
|
|
bos_header.bDescriptorType, LIBUSB_DT_BOS);
|
|
return LIBUSB_ERROR_IO;
|
|
}
|
|
if (bos_header.bLength < LIBUSB_DT_BOS_SIZE) {
|
|
usbi_err(ctx, "invalid bos bLength (%d)", bos_header.bLength);
|
|
return LIBUSB_ERROR_IO;
|
|
}
|
|
if (bos_header.bLength > size) {
|
|
usbi_err(ctx, "short bos descriptor read %d/%d",
|
|
size, bos_header.bLength);
|
|
return LIBUSB_ERROR_IO;
|
|
}
|
|
|
|
_bos = calloc (1,
|
|
sizeof(*_bos) + bos_header.bNumDeviceCaps * sizeof(void *));
|
|
if (!_bos)
|
|
return LIBUSB_ERROR_NO_MEM;
|
|
|
|
usbi_parse_descriptor(buffer, "bbwb", _bos, host_endian);
|
|
buffer += bos_header.bLength;
|
|
size -= bos_header.bLength;
|
|
|
|
/* Get the device capability descriptors */
|
|
for (i = 0; i < bos_header.bNumDeviceCaps; i++) {
|
|
if (size < LIBUSB_DT_DEVICE_CAPABILITY_SIZE) {
|
|
usbi_warn(ctx, "short dev-cap descriptor read %d/%d",
|
|
size, LIBUSB_DT_DEVICE_CAPABILITY_SIZE);
|
|
break;
|
|
}
|
|
usbi_parse_descriptor(buffer, "bbb", &dev_cap, host_endian);
|
|
if (dev_cap.bDescriptorType != LIBUSB_DT_DEVICE_CAPABILITY) {
|
|
usbi_warn(ctx, "unexpected descriptor %x (expected %x)",
|
|
dev_cap.bDescriptorType, LIBUSB_DT_DEVICE_CAPABILITY);
|
|
break;
|
|
}
|
|
if (dev_cap.bLength < LIBUSB_DT_DEVICE_CAPABILITY_SIZE) {
|
|
usbi_err(ctx, "invalid dev-cap bLength (%d)",
|
|
dev_cap.bLength);
|
|
libusb_free_bos_descriptor(_bos);
|
|
return LIBUSB_ERROR_IO;
|
|
}
|
|
if (dev_cap.bLength > size) {
|
|
usbi_warn(ctx, "short dev-cap descriptor read %d/%d",
|
|
size, dev_cap.bLength);
|
|
break;
|
|
}
|
|
|
|
_bos->dev_capability[i] = malloc(dev_cap.bLength);
|
|
if (!_bos->dev_capability[i]) {
|
|
libusb_free_bos_descriptor(_bos);
|
|
return LIBUSB_ERROR_NO_MEM;
|
|
}
|
|
memcpy(_bos->dev_capability[i], buffer, dev_cap.bLength);
|
|
buffer += dev_cap.bLength;
|
|
size -= dev_cap.bLength;
|
|
}
|
|
_bos->bNumDeviceCaps = (uint8_t)i;
|
|
*bos = _bos;
|
|
|
|
return LIBUSB_SUCCESS;
|
|
}
|
|
|
|
/** \ingroup libusb_desc
|
|
* Get a Binary Object Store (BOS) descriptor
|
|
* This is a BLOCKING function, which will send requests to the device.
|
|
*
|
|
* \param dev_handle the handle of an open libusb device
|
|
* \param bos output location for the BOS descriptor. Only valid if 0 was returned.
|
|
* Must be freed with \ref libusb_free_bos_descriptor() after use.
|
|
* \returns 0 on success
|
|
* \returns LIBUSB_ERROR_NOT_FOUND if the device doesn't have a BOS descriptor
|
|
* \returns another LIBUSB_ERROR code on error
|
|
*/
|
|
int API_EXPORTED libusb_get_bos_descriptor(libusb_device_handle *dev_handle,
|
|
struct libusb_bos_descriptor **bos)
|
|
{
|
|
struct libusb_bos_descriptor _bos;
|
|
uint8_t bos_header[LIBUSB_DT_BOS_SIZE] = {0};
|
|
unsigned char *bos_data = NULL;
|
|
const int host_endian = 0;
|
|
int r;
|
|
|
|
/* Read the BOS. This generates 2 requests on the bus,
|
|
* one for the header, and one for the full BOS */
|
|
r = libusb_get_descriptor(dev_handle, LIBUSB_DT_BOS, 0, bos_header,
|
|
LIBUSB_DT_BOS_SIZE);
|
|
if (r < 0) {
|
|
if (r != LIBUSB_ERROR_PIPE)
|
|
usbi_err(HANDLE_CTX(dev_handle), "failed to read BOS (%d)", r);
|
|
return r;
|
|
}
|
|
if (r < LIBUSB_DT_BOS_SIZE) {
|
|
usbi_err(HANDLE_CTX(dev_handle), "short BOS read %d/%d",
|
|
r, LIBUSB_DT_BOS_SIZE);
|
|
return LIBUSB_ERROR_IO;
|
|
}
|
|
|
|
usbi_parse_descriptor(bos_header, "bbwb", &_bos, host_endian);
|
|
usbi_dbg("found BOS descriptor: size %d bytes, %d capabilities",
|
|
_bos.wTotalLength, _bos.bNumDeviceCaps);
|
|
bos_data = calloc(_bos.wTotalLength, 1);
|
|
if (bos_data == NULL)
|
|
return LIBUSB_ERROR_NO_MEM;
|
|
|
|
r = libusb_get_descriptor(dev_handle, LIBUSB_DT_BOS, 0, bos_data,
|
|
_bos.wTotalLength);
|
|
if (r >= 0)
|
|
r = parse_bos(HANDLE_CTX(dev_handle), bos, bos_data, r, host_endian);
|
|
else
|
|
usbi_err(HANDLE_CTX(dev_handle), "failed to read BOS (%d)", r);
|
|
|
|
free(bos_data);
|
|
return r;
|
|
}
|
|
|
|
/** \ingroup libusb_desc
|
|
* Free a BOS descriptor obtained from libusb_get_bos_descriptor().
|
|
* It is safe to call this function with a NULL bos parameter, in which
|
|
* case the function simply returns.
|
|
*
|
|
* \param bos the BOS descriptor to free
|
|
*/
|
|
void API_EXPORTED libusb_free_bos_descriptor(struct libusb_bos_descriptor *bos)
|
|
{
|
|
int i;
|
|
|
|
if (!bos)
|
|
return;
|
|
|
|
for (i = 0; i < bos->bNumDeviceCaps; i++)
|
|
free(bos->dev_capability[i]);
|
|
free(bos);
|
|
}
|
|
|
|
/** \ingroup libusb_desc
|
|
* Get an USB 2.0 Extension descriptor
|
|
*
|
|
* \param ctx the context to operate on, or NULL for the default context
|
|
* \param dev_cap Device Capability descriptor with a bDevCapabilityType of
|
|
* \ref libusb_capability_type::LIBUSB_BT_USB_2_0_EXTENSION
|
|
* LIBUSB_BT_USB_2_0_EXTENSION
|
|
* \param usb_2_0_extension output location for the USB 2.0 Extension
|
|
* descriptor. Only valid if 0 was returned. Must be freed with
|
|
* libusb_free_usb_2_0_extension_descriptor() after use.
|
|
* \returns 0 on success
|
|
* \returns a LIBUSB_ERROR code on error
|
|
*/
|
|
int API_EXPORTED libusb_get_usb_2_0_extension_descriptor(
|
|
struct libusb_context *ctx,
|
|
struct libusb_bos_dev_capability_descriptor *dev_cap,
|
|
struct libusb_usb_2_0_extension_descriptor **usb_2_0_extension)
|
|
{
|
|
struct libusb_usb_2_0_extension_descriptor *_usb_2_0_extension;
|
|
const int host_endian = 0;
|
|
|
|
if (dev_cap->bDevCapabilityType != LIBUSB_BT_USB_2_0_EXTENSION) {
|
|
usbi_err(ctx, "unexpected bDevCapabilityType %x (expected %x)",
|
|
dev_cap->bDevCapabilityType,
|
|
LIBUSB_BT_USB_2_0_EXTENSION);
|
|
return LIBUSB_ERROR_INVALID_PARAM;
|
|
}
|
|
if (dev_cap->bLength < LIBUSB_BT_USB_2_0_EXTENSION_SIZE) {
|
|
usbi_err(ctx, "short dev-cap descriptor read %d/%d",
|
|
dev_cap->bLength, LIBUSB_BT_USB_2_0_EXTENSION_SIZE);
|
|
return LIBUSB_ERROR_IO;
|
|
}
|
|
|
|
_usb_2_0_extension = malloc(sizeof(*_usb_2_0_extension));
|
|
if (!_usb_2_0_extension)
|
|
return LIBUSB_ERROR_NO_MEM;
|
|
|
|
usbi_parse_descriptor((unsigned char *)dev_cap, "bbbd",
|
|
_usb_2_0_extension, host_endian);
|
|
|
|
*usb_2_0_extension = _usb_2_0_extension;
|
|
return LIBUSB_SUCCESS;
|
|
}
|
|
|
|
/** \ingroup libusb_desc
|
|
* Free a USB 2.0 Extension descriptor obtained from
|
|
* libusb_get_usb_2_0_extension_descriptor().
|
|
* It is safe to call this function with a NULL usb_2_0_extension parameter,
|
|
* in which case the function simply returns.
|
|
*
|
|
* \param usb_2_0_extension the USB 2.0 Extension descriptor to free
|
|
*/
|
|
void API_EXPORTED libusb_free_usb_2_0_extension_descriptor(
|
|
struct libusb_usb_2_0_extension_descriptor *usb_2_0_extension)
|
|
{
|
|
free(usb_2_0_extension);
|
|
}
|
|
|
|
/** \ingroup libusb_desc
|
|
* Get a SuperSpeed USB Device Capability descriptor
|
|
*
|
|
* \param ctx the context to operate on, or NULL for the default context
|
|
* \param dev_cap Device Capability descriptor with a bDevCapabilityType of
|
|
* \ref libusb_capability_type::LIBUSB_BT_SS_USB_DEVICE_CAPABILITY
|
|
* LIBUSB_BT_SS_USB_DEVICE_CAPABILITY
|
|
* \param ss_usb_device_cap output location for the SuperSpeed USB Device
|
|
* Capability descriptor. Only valid if 0 was returned. Must be freed with
|
|
* libusb_free_ss_usb_device_capability_descriptor() after use.
|
|
* \returns 0 on success
|
|
* \returns a LIBUSB_ERROR code on error
|
|
*/
|
|
int API_EXPORTED libusb_get_ss_usb_device_capability_descriptor(
|
|
struct libusb_context *ctx,
|
|
struct libusb_bos_dev_capability_descriptor *dev_cap,
|
|
struct libusb_ss_usb_device_capability_descriptor **ss_usb_device_cap)
|
|
{
|
|
struct libusb_ss_usb_device_capability_descriptor *_ss_usb_device_cap;
|
|
const int host_endian = 0;
|
|
|
|
if (dev_cap->bDevCapabilityType != LIBUSB_BT_SS_USB_DEVICE_CAPABILITY) {
|
|
usbi_err(ctx, "unexpected bDevCapabilityType %x (expected %x)",
|
|
dev_cap->bDevCapabilityType,
|
|
LIBUSB_BT_SS_USB_DEVICE_CAPABILITY);
|
|
return LIBUSB_ERROR_INVALID_PARAM;
|
|
}
|
|
if (dev_cap->bLength < LIBUSB_BT_SS_USB_DEVICE_CAPABILITY_SIZE) {
|
|
usbi_err(ctx, "short dev-cap descriptor read %d/%d",
|
|
dev_cap->bLength, LIBUSB_BT_SS_USB_DEVICE_CAPABILITY_SIZE);
|
|
return LIBUSB_ERROR_IO;
|
|
}
|
|
|
|
_ss_usb_device_cap = malloc(sizeof(*_ss_usb_device_cap));
|
|
if (!_ss_usb_device_cap)
|
|
return LIBUSB_ERROR_NO_MEM;
|
|
|
|
usbi_parse_descriptor((unsigned char *)dev_cap, "bbbbwbbw",
|
|
_ss_usb_device_cap, host_endian);
|
|
|
|
*ss_usb_device_cap = _ss_usb_device_cap;
|
|
return LIBUSB_SUCCESS;
|
|
}
|
|
|
|
/** \ingroup libusb_desc
|
|
* Free a SuperSpeed USB Device Capability descriptor obtained from
|
|
* libusb_get_ss_usb_device_capability_descriptor().
|
|
* It is safe to call this function with a NULL ss_usb_device_cap
|
|
* parameter, in which case the function simply returns.
|
|
*
|
|
* \param ss_usb_device_cap the SuperSpeed USB Device Capability descriptor
|
|
* to free
|
|
*/
|
|
void API_EXPORTED libusb_free_ss_usb_device_capability_descriptor(
|
|
struct libusb_ss_usb_device_capability_descriptor *ss_usb_device_cap)
|
|
{
|
|
free(ss_usb_device_cap);
|
|
}
|
|
|
|
/** \ingroup libusb_desc
|
|
* Get a Container ID descriptor
|
|
*
|
|
* \param ctx the context to operate on, or NULL for the default context
|
|
* \param dev_cap Device Capability descriptor with a bDevCapabilityType of
|
|
* \ref libusb_capability_type::LIBUSB_BT_CONTAINER_ID
|
|
* LIBUSB_BT_CONTAINER_ID
|
|
* \param container_id output location for the Container ID descriptor.
|
|
* Only valid if 0 was returned. Must be freed with
|
|
* libusb_free_container_id_descriptor() after use.
|
|
* \returns 0 on success
|
|
* \returns a LIBUSB_ERROR code on error
|
|
*/
|
|
int API_EXPORTED libusb_get_container_id_descriptor(struct libusb_context *ctx,
|
|
struct libusb_bos_dev_capability_descriptor *dev_cap,
|
|
struct libusb_container_id_descriptor **container_id)
|
|
{
|
|
struct libusb_container_id_descriptor *_container_id;
|
|
const int host_endian = 0;
|
|
|
|
if (dev_cap->bDevCapabilityType != LIBUSB_BT_CONTAINER_ID) {
|
|
usbi_err(ctx, "unexpected bDevCapabilityType %x (expected %x)",
|
|
dev_cap->bDevCapabilityType,
|
|
LIBUSB_BT_CONTAINER_ID);
|
|
return LIBUSB_ERROR_INVALID_PARAM;
|
|
}
|
|
if (dev_cap->bLength < LIBUSB_BT_CONTAINER_ID_SIZE) {
|
|
usbi_err(ctx, "short dev-cap descriptor read %d/%d",
|
|
dev_cap->bLength, LIBUSB_BT_CONTAINER_ID_SIZE);
|
|
return LIBUSB_ERROR_IO;
|
|
}
|
|
|
|
_container_id = malloc(sizeof(*_container_id));
|
|
if (!_container_id)
|
|
return LIBUSB_ERROR_NO_MEM;
|
|
|
|
usbi_parse_descriptor((unsigned char *)dev_cap, "bbbbu",
|
|
_container_id, host_endian);
|
|
|
|
*container_id = _container_id;
|
|
return LIBUSB_SUCCESS;
|
|
}
|
|
|
|
/** \ingroup libusb_desc
|
|
* Free a Container ID descriptor obtained from
|
|
* libusb_get_container_id_descriptor().
|
|
* It is safe to call this function with a NULL container_id parameter,
|
|
* in which case the function simply returns.
|
|
*
|
|
* \param container_id the Container ID descriptor to free
|
|
*/
|
|
void API_EXPORTED libusb_free_container_id_descriptor(
|
|
struct libusb_container_id_descriptor *container_id)
|
|
{
|
|
free(container_id);
|
|
}
|
|
|
|
/** \ingroup libusb_desc
|
|
* Retrieve a string descriptor in C style ASCII.
|
|
*
|
|
* Wrapper around libusb_get_string_descriptor(). Uses the first language
|
|
* supported by the device.
|
|
*
|
|
* \param dev_handle a device handle
|
|
* \param desc_index the index of the descriptor to retrieve
|
|
* \param data output buffer for ASCII string descriptor
|
|
* \param length size of data buffer
|
|
* \returns number of bytes returned in data, or LIBUSB_ERROR code on failure
|
|
*/
|
|
int API_EXPORTED libusb_get_string_descriptor_ascii(libusb_device_handle *dev_handle,
|
|
uint8_t desc_index, unsigned char *data, int length)
|
|
{
|
|
unsigned char tbuf[255]; /* Some devices choke on size > 255 */
|
|
int r, si, di;
|
|
uint16_t langid;
|
|
|
|
/* Asking for the zero'th index is special - it returns a string
|
|
* descriptor that contains all the language IDs supported by the
|
|
* device. Typically there aren't many - often only one. Language
|
|
* IDs are 16 bit numbers, and they start at the third byte in the
|
|
* descriptor. There's also no point in trying to read descriptor 0
|
|
* with this function. See USB 2.0 specification section 9.6.7 for
|
|
* more information.
|
|
*/
|
|
|
|
if (desc_index == 0)
|
|
return LIBUSB_ERROR_INVALID_PARAM;
|
|
|
|
r = libusb_get_string_descriptor(dev_handle, 0, 0, tbuf, sizeof(tbuf));
|
|
if (r < 0)
|
|
return r;
|
|
|
|
if (r < 4)
|
|
return LIBUSB_ERROR_IO;
|
|
|
|
langid = (uint16_t)(tbuf[2] | (tbuf[3] << 8));
|
|
|
|
r = libusb_get_string_descriptor(dev_handle, desc_index, langid, tbuf,
|
|
sizeof(tbuf));
|
|
if (r < 0)
|
|
return r;
|
|
|
|
if (tbuf[1] != LIBUSB_DT_STRING)
|
|
return LIBUSB_ERROR_IO;
|
|
|
|
if (tbuf[0] > r)
|
|
return LIBUSB_ERROR_IO;
|
|
|
|
di = 0;
|
|
for (si = 2; si < tbuf[0]; si += 2) {
|
|
if (di >= (length - 1))
|
|
break;
|
|
|
|
if ((tbuf[si] & 0x80) || (tbuf[si + 1])) /* non-ASCII */
|
|
data[di++] = '?';
|
|
else
|
|
data[di++] = tbuf[si];
|
|
}
|
|
|
|
data[di] = 0;
|
|
return di;
|
|
}
|