Return-Path: From: Arman Uguray To: linux-bluetooth@vger.kernel.org Cc: Arman Uguray Subject: [PATCH v2 10/11] shared/gatt: Implement "Write Long Values" procedure. Date: Fri, 25 Jul 2014 15:08:42 -0700 Message-Id: <1406326123-10564-11-git-send-email-armansito@chromium.org> In-Reply-To: <1406326123-10564-1-git-send-email-armansito@chromium.org> References: <1406326123-10564-1-git-send-email-armansito@chromium.org> Sender: linux-bluetooth-owner@vger.kernel.org List-ID: This patch implements bt_gatt_write_long_value. --- src/shared/gatt-helpers.c | 240 +++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 238 insertions(+), 2 deletions(-) diff --git a/src/shared/gatt-helpers.c b/src/shared/gatt-helpers.c index a1e8d79..59fddab 100644 --- a/src/shared/gatt-helpers.c +++ b/src/shared/gatt-helpers.c @@ -1230,6 +1230,180 @@ bool bt_gatt_write_value(struct bt_att *att, uint16_t value_handle, return true; } +struct write_long_op { + struct bt_att *att; + int ref_count; + bool reliable; + bool success; + uint8_t att_ecode; + bool reliable_error; + uint16_t value_handle; + uint8_t *value; + uint16_t length; + uint16_t offset; + uint16_t index; + uint16_t cur_length; + bt_gatt_write_long_callback_t callback; + void *user_data; + bt_gatt_destroy_func_t destroy; +}; + +static struct write_long_op *write_long_op_ref(struct write_long_op *op) +{ + __sync_fetch_and_add(&op->ref_count, 1); + + return op; +} + +static void write_long_op_unref(void *data) +{ + struct write_long_op *op = data; + + if (__sync_sub_and_fetch(&op->ref_count, 1)) + return; + + if (op->destroy) + op->destroy(op->user_data); + + free(op->value); + free(op); +} + +static void execute_write_cb(uint8_t opcode, const void *pdu, uint16_t length, + void *user_data) +{ + struct write_long_op *op = user_data; + bool success = op->success; + uint8_t att_ecode = op->att_ecode; + + if (opcode == BT_ATT_OP_ERROR_RSP) { + success = false; + att_ecode = process_error(pdu, length); + } else if (opcode != BT_ATT_OP_EXEC_WRITE_RSP || pdu || length) + success = false; + + if (op->callback) + op->callback(success, op->reliable_error, att_ecode, + op->user_data); +} + +static void complete_write_long_op(struct write_long_op *op, bool success, + uint8_t att_ecode, bool reliable_error) +{ + uint8_t pdu; + + op->success = success; + op->att_ecode = att_ecode; + op->reliable_error = reliable_error; + + if (success) + pdu = 0x01; /* Write */ + else + pdu = 0x00; /* Cancel */ + + if (bt_att_send(op->att, BT_ATT_OP_EXEC_WRITE_REQ, &pdu, sizeof(pdu), + execute_write_cb, + write_long_op_ref(op), + write_long_op_unref)) + return; + + write_long_op_unref(op); + success = false; + + if (op->callback) + op->callback(success, reliable_error, att_ecode, op->user_data); +} + +static void prepare_write_cb(uint8_t opcode, const void *pdu, uint16_t length, + void *user_data) +{ + struct write_long_op *op = user_data; + bool success = true; + bool reliable_error = false; + uint8_t att_ecode = 0; + uint16_t next_index; + + if (opcode == BT_ATT_OP_ERROR_RSP) { + success = false; + att_ecode = process_error(pdu, length); + goto done; + } + + if (opcode != BT_ATT_OP_PREP_WRITE_RSP) { + success = false; + goto done; + } + + if (op->reliable) { + if (!pdu || length != (op->cur_length + 4)) { + success = false; + reliable_error = true; + goto done; + } + + if (get_le16(pdu) != op->value_handle || + get_le16(pdu + 2) != (op->offset + op->index)) { + success = false; + reliable_error = true; + goto done; + } + + if (memcmp(pdu + 4, op->value + op->index, op->cur_length)) { + success = false; + reliable_error = true; + goto done; + } + } + + next_index = op->index + op->cur_length; + if (next_index == op->length) { + /* All bytes written */ + goto done; + } + + /* If the last written length greater than or equal to what can fit + * inside a PDU, then there is more data to send. + */ + if (op->cur_length >= bt_att_get_mtu(op->att) - 5) { + uint8_t *pdu; + + op->index = next_index; + op->cur_length = MIN(op->length - op->index, + bt_att_get_mtu(op->att) - 5); + + pdu = malloc(op->cur_length + 4); + if (!pdu) { + success = false; + goto done; + } + + put_le16(op->value_handle, pdu); + put_le16(op->offset + op->index, pdu + 2); + memcpy(pdu + 4, op->value + op->index, op->cur_length); + + if (!bt_att_send(op->att, BT_ATT_OP_PREP_WRITE_REQ, + pdu, op->cur_length + 4, + prepare_write_cb, + write_long_op_ref(op), + write_long_op_unref)) { + write_long_op_unref(op); + success = false; + } + + free(pdu); + + /* If so far successful, then the operation should continue. + * Otherwise, there was an error and the procedure should be + * completed. + */ + if (success) + return; + } + +done: + complete_write_long_op(op, success, att_ecode, reliable_error); +} + bool bt_gatt_write_long_value(struct bt_att *att, bool reliable, uint16_t value_handle, uint16_t offset, uint8_t *value, uint16_t length, @@ -1237,8 +1411,70 @@ bool bt_gatt_write_long_value(struct bt_att *att, bool reliable, void *user_data, bt_gatt_destroy_func_t destroy) { - /* TODO */ - return false; + struct write_long_op *op; + uint8_t *pdu; + bool status; + + if (!att) + return false; + + if ((size_t)(length + offset) > UINT16_MAX) + return false; + + /* Don't allow riting a 0-length value using this procedure. The + * upper-layer should use bt_gatt_write_value for that instead. + */ + if (!length || !value) + return false; + + op = new0(struct write_long_op, 1); + if (!op) + return false; + + op->value = malloc(length); + if (!op->value) { + free(op); + return false; + } + + memcpy(op->value, value, length); + + op->att = att; + op->reliable = reliable; + op->value_handle = value_handle; + op->length = length; + op->offset = offset; + op->cur_length = MIN(length, bt_att_get_mtu(att) - 5); + op->callback = callback; + op->user_data = user_data; + op->destroy = destroy; + + pdu = malloc(op->cur_length + 4); + if (!pdu) { + free(op->value); + free(op); + return false; + } + + put_le16(value_handle, pdu); + put_le16(offset, pdu + 2); + memcpy(pdu + 4, op->value, op->cur_length); + + status = bt_att_send(att, BT_ATT_OP_PREP_WRITE_REQ, + pdu, op->cur_length + 4, + prepare_write_cb, + write_long_op_ref(op), + write_long_op_unref); + + free(pdu); + + if (!status) { + free(op->value); + free(op); + return false; + } + + return true; } unsigned int bt_gatt_register(struct bt_att *att, bool indications, -- 2.0.0.526.g5318336