[RFC BlueZ 1/1] src/shared/gatt: Introduce bt_gatt skeleton.

[Arman Uguray <armansito@chromium.org>]

This patch introduces src/shared/gatt, which provides an interface for
GATT client operations. bt_gatt will internally use src/shared/att for
ATT protocol client-side operations. bt_gatt is meant to be used
together with src/shared/gatt-db to implement a complete GATT client.
---
 Makefile.am       |   3 +-
 src/shared/gatt.c | 192 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 src/shared/gatt.h | 189 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 383 insertions(+), 1 deletion(-)
 create mode 100644 src/shared/gatt.c
 create mode 100644 src/shared/gatt.h

diff --git a/Makefile.am b/Makefile.am
index 04be6c4..8b731f0 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -156,7 +156,8 @@ src_bluetoothd_SOURCES = $(builtin_sources) \
 			src/shared/queue.h src/shared/queue.c \
 			src/shared/util.h src/shared/util.c \
 			src/shared/mgmt.h src/shared/mgmt.c \
-			src/shared/att.h src/shared/att.c
+			src/shared/att.h src/shared/att.c \
+			src/shared/gatt.h src/shared/gatt.c
 src_bluetoothd_LDADD = lib/libbluetooth-internal.la gdbus/libgdbus-internal.la \
 			@GLIB_LIBS@ @DBUS_LIBS@ -ldl -lrt
 src_bluetoothd_LDFLAGS = $(AM_LDFLAGS) -Wl,--export-dynamic \
diff --git a/src/shared/gatt.c b/src/shared/gatt.c
new file mode 100644
index 0000000..2e701dc
--- /dev/null
+++ b/src/shared/gatt.c
@@ -0,0 +1,192 @@
+/*
+ *
+ *  BlueZ - Bluetooth protocol stack for Linux
+ *
+ *  Copyright (C) 2014  Google Inc.
+ *
+ *
+ *  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 St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ */
+
+#include "lib/uuid.h"
+#include "src/shared/queue.h"
+#include "src/shared/gatt.h"
+#include "src/shared/att.h"
+
+struct bt_gatt {
+	struct bt_att *att;
+};
+
+struct bt_gatt *bt_gatt_new(int fd)
+{
+	/* TODO: Implement. */
+	return NULL;
+}
+
+void bt_gatt_destroy(struct bt_gatt *gatt)
+{
+	/* TODO: Implement. */
+}
+
+
+unsigned int bt_gatt_register(struct bt_gatt *gatt, uint16_t value_handle,
+					bt_gatt_event_callback_t callback,
+					void *user_data)
+{
+	/* TODO: Implement. */
+	return 0;
+}
+
+bool bt_gatt_unregister(unsigned int id)
+{
+	/* TODO: Implement. */
+	return false;
+}
+
+bool bt_gatt_exchange_mtu(struct bt_gatt *gatt, uint16_t mtu,
+				bt_gatt_exchange_mtu_callback_t callback,
+				void *user_data)
+{
+	/* TODO: Implement. */
+	return false;
+}
+
+uint16_t get_mtu(struct bt_gatt *gatt)
+{
+	/* TODO: Implement. */
+	return 0;
+}
+
+bool bt_gatt_discover_primary_services(struct bt_gatt *gatt, bt_uuid_t *uuid,
+					bt_gatt_discovery_callback_t callback,
+					void *user_data)
+{
+	/* TODO: Implement. */
+	return false;
+}
+
+bool bt_gatt_discover_included_services(struct bt_gatt *gatt,
+					struct bt_gatt_handle_range range,
+					bt_uuid_t *uuid,
+					bt_gatt_discovery_callback_t callback,
+					void *user_data)
+{
+	/* TODO: Implement. */
+	return false;
+}
+
+bool bt_gatt_discover_characteristics(struct bt_gatt *gatt,
+					struct bt_gatt_handle_range range,
+					bt_uuid_t *uuid,
+					bt_gatt_discovery_callback_t callback,
+					void *user_data)
+{
+	/* TODO: Implement. */
+	return false;
+}
+
+bool bt_gatt_discover_descriptors(struct bt_gatt *gatt,
+					struct bt_gatt_handle_range range,
+					bt_gatt_discovery_callback_t callback,
+					void *user_data)
+{
+	/* TODO: Implement. */
+	return false;
+}
+
+bool bt_gatt_read_characteristic_value(struct bt_gatt *gatt,
+					uint16_t value_handle,
+					bt_gatt_read_callback_t callback,
+					void *user_data)
+{
+	/* TODO: Implement. */
+	return false;
+}
+
+bool bt_gatt_read_long_characteristic_values(struct bt_gatt *gatt,
+					uint16_t value_handle, uint16_t offset,
+					bt_gatt_read_callback_t callback,
+					void *user_data)
+{
+	/* TODO: Implement. */
+	return false;
+}
+
+bool bt_gatt_write_without_response(struct bt_gatt *gatt,
+					uint16_t value_handle,
+					uint8_t *value, uint16_t length)
+{
+	/* TODO: Implement. */
+	return false;
+}
+
+bool bt_gatt_write_characteristic_value(struct bt_gatt *gatt,
+					uint16_t value_handle,
+					uint8_t *value, uint16_t length,
+					bt_gatt_result_callback_t callback,
+					void *user_data)
+{
+	/* TODO: Implement. */
+	return false;
+}
+
+bool bt_gatt_write_long_characteristic_values(struct bt_gatt *gatt,
+					uint16_t value_handle, uint16_t offset,
+					uint8_t *value, uint16_t length,
+					bt_gatt_result_callback_t callback,
+					void *user_data)
+{
+	/* TODO: Implement. */
+	return false;
+}
+
+bool bt_gatt_read_characteristic_descriptors(struct bt_gatt *gatt,
+					uint16_t value_handle,
+					bt_gatt_read_callback_t callback,
+					void *user_data)
+{
+	/* TODO: Implement. */
+	return false;
+}
+
+bool bt_gatt_read_long_characteristic_descriptors(struct bt_gatt *gatt,
+					uint16_t value_handle, uint16_t offset,
+					bt_gatt_read_callback_t callback,
+					void *user_data)
+{
+	/* TODO: Implement. */
+	return false;
+}
+
+bool bt_gatt_write_characteristic_descriptors(struct bt_gatt *gatt,
+					uint16_t value_handle,
+					uint8_t *value, uint16_t length,
+					bt_gatt_result_callback_t callback,
+					void *user_data)
+{
+	/* TODO: Implement. */
+	return false;
+}
+
+bool bt_gatt_write_long_characteristic_descriptors(struct bt_gatt *gatt,
+					uint16_t value_handle, uint16_t offset,
+					uint8_t *value, uint16_t length,
+					bt_gatt_result_callback_t callback,
+					void *user_data)
+{
+	/* TODO: Implement. */
+	return false;
+}
diff --git a/src/shared/gatt.h b/src/shared/gatt.h
new file mode 100644
index 0000000..624bd87
--- /dev/null
+++ b/src/shared/gatt.h
@@ -0,0 +1,189 @@
+/*
+ *
+ *  BlueZ - Bluetooth protocol stack for Linux
+ *
+ *  Copyright (C) 2014  Google Inc.
+ *
+ *
+ *  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 St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ */
+
+/*
+ * An instance of struct bt_gatt comprises a client-side implementation
+ * of the Generic Attribute Profile (GATT) with regards to a specific remote
+ * GATT server. Each instance is created with a file descriptor that represents
+ * the logical link to the server, which must be configured s.t. communication
+ * via the Attribute Protocol is possible (e.g. an L2CAP LE connection over the
+ * ATT channel). bt_gatt provides functions to perform GATT client
+ * operations, such as primary service discovery, characteristic reads and
+ * writes, etc which are performed over the given connection.
+ *
+ * Most GATT clients will implement some sort of attribute caching to reduce the
+ * number operations performed over-the-air. While an instance of bt_gatt does
+ * not maintain a cache of attributes, it provides the means to get notified
+ * when notifications/indications are received. This can be used to maintain and
+ * update a separate database following events such as indications from the
+ * Service Changed characteristic or based on updates to the underlying
+ * connection (e.g. a disconnect event).
+ */
+
+#include <stdbool.h>
+#include <stdint.h>
+
+struct bt_gatt;
+
+struct bt_gatt_handle_range {
+	uint16_t start;
+	uint16_t end;
+};
+
+struct bt_gatt_service {
+	bt_uuid_t uuid;
+	struct bt_gatt_handle_range handle_range;
+};
+
+struct bt_gatt_characteristic {
+	uint8_t properties;
+	uint16_t value_handle;
+	bt_uuid_t uuid;
+	struct bt_gatt_handle_range handle_range;
+};
+
+struct bt_gatt_descriptor {
+	uint16_t handle;
+	bt_uuid_t uuid;
+};
+
+typedef enum {
+	BT_GATT_EVENT_TYPE_HANDLE_VALUE_NOTIFICATION,
+	BT_GATT_EVENT_TYPE_HANDLE_VALUE_INDICATION,
+} bt_gatt_event_type_t;
+
+typedef void (*bt_gatt_confirmation_callback_t)(void);
+
+typedef void (*bt_gatt_event_callback_t)(bt_gatt_event_type_t event_type,
+				uint16_t value_handle,
+				uint8_t *value, uint16_t length,
+				bt_gatt_confirmation_callback_t conf_callback,
+				void *user_data);
+
+typedef void (*bt_gatt_exchange_mtu_callback_t)(uint16_t final_mtu,
+							void *user_data);
+
+/*
+ * "status" is set to 0 if the operation was successful. Otherwise, it is set
+ * to the ATT protocol error code. See the error codes defined in
+ * src/shared/att.h.
+ */
+typedef void (*bt_gatt_discovery_callback_t)(uint8_t status,
+							struct queue *list,
+							void *user_data);
+
+typedef void (*bt_gatt_read_callback_t)(uint8_t status, uint8_t *value,
+					uint16_t length, void *user_data);
+
+typedef void (*bt_gatt_result_callback_t)(uint8_t status, void *user_data);
+
+struct bt_gatt *bt_gatt_new(int fd);
+void bt_gatt_destroy(struct bt_gatt *gatt);
+
+
+/******* Notifications/Indications *******/
+unsigned int bt_gatt_register(struct bt_gatt *gatt, uint16_t value_handle,
+					bt_gatt_event_callback_t callback,
+					void *user_data);
+bool bt_gatt_unregister(unsigned int id);
+
+/******* Server Configuration *******/
+bool bt_gatt_exchange_mtu(struct bt_gatt *gatt, uint16_t mtu,
+				bt_gatt_exchange_mtu_callback_t callback,
+				void *user_data);
+
+uint16_t get_mtu(struct bt_gatt *gatt);
+
+/******* Primary Service/Relationship/Characteristic/Descriptor discovery *****/
+bool bt_gatt_discover_primary_services(struct bt_gatt *gatt, bt_uuid_t *uuid,
+					bt_gatt_discovery_callback_t callback,
+					void *user_data);
+
+bool bt_gatt_discover_included_services(struct bt_gatt *gatt,
+					struct bt_gatt_handle_range range,
+					bt_uuid_t *uuid,
+					bt_gatt_discovery_callback_t callback,
+					void *user_data);
+
+bool bt_gatt_discover_characteristics(struct bt_gatt *gatt,
+					struct bt_gatt_handle_range range,
+					bt_uuid_t *uuid,
+					bt_gatt_discovery_callback_t callback,
+					void *user_data);
+
+bool bt_gatt_discover_descriptors(struct bt_gatt *gatt,
+					struct bt_gatt_handle_range range,
+					bt_gatt_discovery_callback_t callback,
+					void *user_data);
+
+/******* Characteristic Value Read *******/
+bool bt_gatt_read_characteristic_value(struct bt_gatt *gatt,
+					uint16_t value_handle,
+					bt_gatt_read_callback_t callback,
+					void *user_data);
+
+bool bt_gatt_read_long_characteristic_values(struct bt_gatt *gatt,
+					uint16_t value_handle, uint16_t offset,
+					bt_gatt_read_callback_t callback,
+					void *user_data);
+
+/******* Characteristic Value Write *******/
+bool bt_gatt_write_without_response(struct bt_gatt *gatt,
+					uint16_t value_handle,
+					uint8_t *value, uint16_t length);
+
+bool bt_gatt_write_characteristic_value(struct bt_gatt *gatt,
+					uint16_t value_handle,
+					uint8_t *value, uint16_t length,
+					bt_gatt_result_callback_t callback,
+					void *user_data);
+
+bool bt_gatt_write_long_characteristic_values(struct bt_gatt *gatt,
+					uint16_t value_handle, uint16_t offset,
+					uint8_t *value, uint16_t length,
+					bt_gatt_result_callback_t callback,
+					void *user_data);
+
+/******* Characteristic Descriptor Value Read *******/
+bool bt_gatt_read_characteristic_descriptors(struct bt_gatt *gatt,
+					uint16_t value_handle,
+					bt_gatt_read_callback_t callback,
+					void *user_data);
+
+bool bt_gatt_read_long_characteristic_descriptors(struct bt_gatt *gatt,
+					uint16_t value_handle, uint16_t offset,
+					bt_gatt_read_callback_t callback,
+					void *user_data);
+
+/******* Characteristic Descriptor Value Write *******/
+bool bt_gatt_write_characteristic_descriptors(struct bt_gatt *gatt,
+					uint16_t value_handle,
+					uint8_t *value, uint16_t length,
+					bt_gatt_result_callback_t callback,
+					void *user_data);
+
+bool bt_gatt_write_long_characteristic_descriptors(struct bt_gatt *gatt,
+					uint16_t value_handle, uint16_t offset,
+					uint8_t *value, uint16_t length,
+					bt_gatt_result_callback_t callback,
+					void *user_data);
-- 
1.8.3.2