Add support for getting BOS descriptors

8 files changed, 275 insertions, 0 deletions

diff --git a/gusb/gusb-bos-descriptor-private.h b/gusb/gusb-bos-descriptor-private.h
new file mode 100644
index 0000000..4db8320
--- /dev/null
+++ b/gusb/gusb-bos-descriptor-private.h
@@ -0,0 +1,18 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ *
+ * Copyright (C) 2022 Richard Hughes <richard@hughsie.com>
+ *
+ * SPDX-License-Identifier: LGPL-2.1+
+ */
+
+#pragma once
+
+#include <libusb.h>
+
+#include <gusb/gusb-bos-descriptor.h>
+
+G_BEGIN_DECLS
+
+GUsbBosDescriptor	*_g_usb_bos_descriptor_new	(const struct libusb_bos_dev_capability_descriptor	*bos_cap);
+
+G_END_DECLS
diff --git a/gusb/gusb-bos-descriptor.c b/gusb/gusb-bos-descriptor.c
new file mode 100644
index 0000000..b0664f8
--- /dev/null
+++ b/gusb/gusb-bos-descriptor.c
@@ -0,0 +1,109 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ *
+ * Copyright (C) 2022 Richard Hughes <richard@hughsie.com>
+ *
+ * SPDX-License-Identifier: LGPL-2.1+
+ */
+
+/**
+ * SECTION:gusb-bos-descriptor
+ * @short_description: GLib wrapper around a USB BOS descriptor.
+ *
+ * This object is a thin glib wrapper around a `libusb_bos_dev_capability_descriptor`.
+ *
+ * All the data is copied when the object is created and the original descriptor can be destroyed
+ * at any point.
+ */
+
+#include "config.h"
+
+#include <string.h>
+
+#include "gusb-bos-descriptor-private.h"
+
+struct _GUsbBosDescriptor
+{
+	GObject parent_instance;
+
+	struct libusb_bos_dev_capability_descriptor bos_cap;
+	GBytes *extra;
+};
+
+G_DEFINE_TYPE (GUsbBosDescriptor, g_usb_bos_descriptor, G_TYPE_OBJECT)
+
+static void
+g_usb_bos_descriptor_finalize (GObject *object)
+{
+	GUsbBosDescriptor *self = G_USB_BOS_DESCRIPTOR (object);
+
+	g_bytes_unref (self->extra);
+
+	G_OBJECT_CLASS (g_usb_bos_descriptor_parent_class)->finalize (object);
+}
+
+static void
+g_usb_bos_descriptor_class_init (GUsbBosDescriptorClass *klass)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+	object_class->finalize = g_usb_bos_descriptor_finalize;
+}
+
+static void
+g_usb_bos_descriptor_init (GUsbBosDescriptor *self)
+{
+}
+
+/**
+ * _g_usb_bos_descriptor_new:
+ *
+ * Return value: a new #GUsbBosDescriptor object.
+ *
+ * Since: 0.4.0
+ **/
+GUsbBosDescriptor *
+_g_usb_bos_descriptor_new (const struct libusb_bos_dev_capability_descriptor *bos_cap)
+{
+	GUsbBosDescriptor *self;
+	self = g_object_new (G_USB_TYPE_BOS_DESCRIPTOR, NULL);
+
+	/* copy the data */
+	memcpy (&self->bos_cap, bos_cap, sizeof (*bos_cap));
+	self->extra = g_bytes_new (bos_cap->dev_capability_data, bos_cap->bLength - 0x03);
+
+	return G_USB_BOS_DESCRIPTOR (self);
+}
+
+/**
+ * g_usb_bos_descriptor_get_capability:
+ * @self: a #GUsbBosDescriptor
+ *
+ * Gets the BOS descriptor capability.
+ *
+ * Return value: capability
+ *
+ * Since: 0.4.0
+ **/
+guint8
+g_usb_bos_descriptor_get_capability (GUsbBosDescriptor *self)
+{
+	g_return_val_if_fail (G_USB_IS_BOS_DESCRIPTOR (self), 0);
+	return self->bos_cap.bDevCapabilityType;
+}
+
+/**
+ * g_usb_bos_descriptor_get_extra:
+ * @self: a #GUsbBosDescriptor
+ *
+ * Gets any extra data from the BOS descriptor.
+ *
+ * Return value: (transfer none): a #GBytes, or %NULL for failure
+ *
+ * Since: 0.4.0
+ **/
+GBytes *
+g_usb_bos_descriptor_get_extra (GUsbBosDescriptor *self)
+{
+	g_return_val_if_fail (G_USB_IS_BOS_DESCRIPTOR (self), NULL);
+	return self->extra;
+}
diff --git a/gusb/gusb-bos-descriptor.h b/gusb/gusb-bos-descriptor.h
new file mode 100644
index 0000000..813779e
--- /dev/null
+++ b/gusb/gusb-bos-descriptor.h
@@ -0,0 +1,20 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ *
+ * Copyright (C) 2022 Richard Hughes <richard@hughsie.com>
+ *
+ * SPDX-License-Identifier: LGPL-2.1+
+ */
+
+#pragma once
+
+#include <glib-object.h>
+
+G_BEGIN_DECLS
+
+#define G_USB_TYPE_BOS_DESCRIPTOR (g_usb_bos_descriptor_get_type ())
+G_DECLARE_FINAL_TYPE (GUsbBosDescriptor, g_usb_bos_descriptor, G_USB, BOS_DESCRIPTOR, GObject)
+
+guint8		 g_usb_bos_descriptor_get_capability	(GUsbBosDescriptor	*self);
+GBytes		*g_usb_bos_descriptor_get_extra		(GUsbBosDescriptor	*self);
+
+G_END_DECLS
diff --git a/gusb/gusb-device.c b/gusb/gusb-device.c
index 81f90ad..beec181 100644
--- a/gusb/gusb-device.c
+++ b/gusb/gusb-device.c
@@ -24,6 +24,7 @@
 #include "gusb-util.h"
 #include "gusb-device-private.h"
 #include "gusb-interface-private.h"
+#include "gusb-bos-descriptor-private.h"
 
 /**
  * GUsbDevicePrivate:
@@ -607,6 +608,108 @@ g_usb_device_get_interfaces (GUsbDevice *device, GError **error)
 }
 
 /**
+ * g_usb_device_get_bos_descriptor:
+ * @device: a #GUsbDevice
+ * @capability: a BOS capability type
+ * @error: a #GError, or %NULL
+ *
+ * Gets the first bos_descriptor that matches the descriptor capability.
+ * If you want to find all the BOS descriptors that match (there may be other matching BOS
+ * descriptors you have to use `g_usb_device_get_bos_descriptors()` and check each one manually.
+ *
+ * Return value: (transfer full): a #GUsbBosDescriptor or %NULL for not found
+ *
+ * Since: 0.4.0
+ **/
+GUsbBosDescriptor *
+g_usb_device_get_bos_descriptor (GUsbDevice *device,
+				 guint8      capability,
+				 GError    **error)
+{
+	gint rc;
+	guint8 num_device_caps;
+	GUsbBosDescriptor *bos_descriptor = NULL;
+	struct libusb_bos_descriptor *bos = NULL;
+
+	g_return_val_if_fail (G_USB_IS_DEVICE (device), NULL);
+	g_return_val_if_fail (error == NULL || *error == NULL, NULL);
+
+	rc = libusb_get_bos_descriptor (device->priv->handle, &bos);
+	if (!g_usb_device_libusb_error_to_gerror (device, rc, error))
+		return NULL;
+
+	/* find the right data */
+#ifdef __FreeBSD__
+	num_device_caps = bos->bNumDeviceCapabilities;
+#else
+	num_device_caps = bos->bNumDeviceCaps;
+#endif
+	for (guint i = 0; i < num_device_caps; i++) {
+		struct libusb_bos_dev_capability_descriptor *bos_cap = bos->dev_capability[i];
+		if (bos_cap->bDevCapabilityType == capability) {
+			bos_descriptor = _g_usb_bos_descriptor_new (bos_cap);
+			break;
+		}
+	}
+
+	/* nothing matched */
+	if (bos_descriptor == NULL) {
+		g_set_error (error,
+			     G_USB_DEVICE_ERROR,
+			     G_USB_DEVICE_ERROR_NOT_SUPPORTED,
+			     "no BOS descriptor for capability 0x%02x",
+			     capability);
+	}
+
+	libusb_free_bos_descriptor (bos);
+	return bos_descriptor;
+}
+
+/**
+ * g_usb_device_get_bos_descriptors:
+ * @device: a #GUsbDevice
+ * @error: a #GError, or %NULL
+ *
+ * Gets all the BOS descriptors exported by the device.
+ *
+ * Return value: (transfer container) (element-type GUsbBosDescriptor): an array of BOS descriptors
+ *
+ * Since: 0.4.0
+ **/
+GPtrArray *
+g_usb_device_get_bos_descriptors (GUsbDevice *device, GError **error)
+{
+	gint rc;
+	guint8 num_device_caps;
+	struct libusb_bos_descriptor *bos = NULL;
+	GPtrArray *array = NULL;
+
+	g_return_val_if_fail (G_USB_IS_DEVICE (device), NULL);
+	g_return_val_if_fail (error == NULL || *error == NULL, NULL);
+
+	rc = libusb_get_bos_descriptor (device->priv->handle, &bos);
+	if (!g_usb_device_libusb_error_to_gerror (device, rc, error))
+		return NULL;
+
+	/* get all BOS descriptors */
+	array = g_ptr_array_new_with_free_func ((GDestroyNotify) g_object_unref);
+#ifdef __FreeBSD__
+	num_device_caps = bos->bNumDeviceCapabilities;
+#else
+	num_device_caps = bos->bNumDeviceCaps;
+#endif
+	for (guint i = 0; i < num_device_caps; i++) {
+		GUsbBosDescriptor *bos_descriptor = NULL;
+		struct libusb_bos_dev_capability_descriptor *bos_cap = bos->dev_capability[i];
+		bos_descriptor = _g_usb_bos_descriptor_new (bos_cap);
+		g_ptr_array_add (array, bos_descriptor);
+	}
+
+	libusb_free_bos_descriptor (bos);
+	return array;
+}
+
+/**
  * g_usb_device_close:
  * @device: a #GUsbDevice
  * @error: a #GError, or %NULL
diff --git a/gusb/gusb-device.h b/gusb/gusb-device.h
index 34085f9..a4f6140 100644
--- a/gusb/gusb-device.h
+++ b/gusb/gusb-device.h
@@ -12,6 +12,7 @@
 
 #include <gusb/gusb-util.h>
 #include <gusb/gusb-interface.h>
+#include <gusb/gusb-bos-descriptor.h>
 
 G_BEGIN_DECLS
 
@@ -184,6 +185,12 @@ GUsbInterface		*g_usb_device_get_interface	(GUsbDevice	*device,
 GPtrArray		*g_usb_device_get_interfaces	(GUsbDevice	*device,
 							 GError		**error);
 
+GPtrArray		*g_usb_device_get_bos_descriptors(GUsbDevice	*device,
+							 GError		**error);
+GUsbBosDescriptor	*g_usb_device_get_bos_descriptor(GUsbDevice	*device,
+							 guint8		 capability,
+							 GError		**error);
+
 gboolean		 g_usb_device_open		(GUsbDevice	*device,
 							 GError		**error);
 gboolean		 g_usb_device_close		(GUsbDevice	*device,
diff --git a/gusb/gusb.h b/gusb/gusb.h
index 96f860c..d8ffea0 100644
--- a/gusb/gusb.h
+++ b/gusb/gusb.h
@@ -12,6 +12,7 @@
 #include <gusb/gusb-autocleanups.h>
 #include <gusb/gusb-context.h>
 #include <gusb/gusb-interface.h>
+#include <gusb/gusb-bos-descriptor.h>
 #include <gusb/gusb-endpoint.h>
 #include <gusb/gusb-source.h>
 #include <gusb/gusb-device.h>
diff --git a/gusb/libgusb.ver b/gusb/libgusb.ver
index 5bf17f7..2bdd669 100644
--- a/gusb/libgusb.ver
+++ b/gusb/libgusb.ver
@@ -166,3 +166,13 @@ LIBGUSB_0.3.10 {
     g_usb_context_set_hotplug_poll_interval;
   local: *;
 } LIBGUSB_0.3.8;
+
+LIBGUSB_0.4.0 {
+  global:
+    g_usb_bos_descriptor_get_capability;
+    g_usb_bos_descriptor_get_extra;
+    g_usb_bos_descriptor_get_type;
+    g_usb_device_get_bos_descriptor;
+    g_usb_device_get_bos_descriptors;
+  local: *;
+} LIBGUSB_0.3.10;
diff --git a/gusb/meson.build b/gusb/meson.build
index 243b0be..150e8b5 100644
--- a/gusb/meson.build
+++ b/gusb/meson.build
@@ -34,6 +34,8 @@ install_headers([
     'gusb-device-list.h',
     'gusb-interface.h',
     'gusb-interface-private.h',
+    'gusb-bos-descriptor.h',
+    'gusb-bos-descriptor-private.h',
     'gusb-endpoint.h',
     'gusb-endpoint-private.h',
     'gusb-source.h',
@@ -56,6 +58,7 @@ gusb = library(
     'gusb-device.c',
     'gusb-device-list.c',
     'gusb-interface.c',
+    'gusb-bos-descriptor.c',
     'gusb-endpoint.c',
     'gusb-source.c',
     'gusb-util.c',
@@ -115,6 +118,9 @@ libgusb_girtarget = gnome.generate_gir(gusb,
     'gusb-interface.c',
     'gusb-interface.h',
     'gusb-interface-private.h',
+    'gusb-bos-descriptor.c',
+    'gusb-bos-descriptor.h',
+    'gusb-bos-descriptor-private.h',
     'gusb-endpoint.c',
     'gusb-endpoint.h',
     'gusb-endpoint-private.h',
@@ -196,6 +202,7 @@ if get_option('tests')
       'gusb-device.c',
       'gusb-device-list.c',
       'gusb-interface.c',
+      'gusb-bos-descriptor.c',
       'gusb-endpoint.c',
       'gusb-self-test.c',
       'gusb-source.c',