text: /**************************************************************************
  *
  * Copyright (C) 2005 Steve Karg <skarg@users.sourceforge.net>
  *
  * Permission is hereby granted, free of charge, to any person obtaining
  * a copy of this software and associated documentation files (the
  * "Software"), to deal in the Software without restriction, including
  * without limitation the rights to use, copy, modify, merge, publish,
  * distribute, sublicense, and/or sell copies of the Software, and to
  * permit persons to whom the Software is furnished to do so, subject to
  * the following conditions:
  *
  * The above copyright notice and this permission notice shall be included
  * in all copies or substantial portions of the Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
  * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  *
  *********************************************************************/
  #include <stddef.h>
  #include <stdint.h>
  #include <stdio.h>
  #include <string.h>
  #include <errno.h>
  #include "config.h"
  #include "txbuf.h"
  #include "bacdef.h"
  #include "bacdcode.h"
  #include "bacerror.h"
  #include "bacdevobjpropref.h"
  #include "apdu.h"
  #include "npdu.h"
  #include "abort.h"
  #include "reject.h"
  #include "rp.h"
  /* device object has custom handler for all objects */
  #include "device.h"
  #include "handlers.h"
  
  /** @file h_rp.c  Handles Read Property requests. */
  
  
  /** Handler for a ReadProperty Service request.
   * @ingroup DSRP
   * This handler will be invoked by apdu_handler() if it has been enabled
   * by a call to apdu_set_confirmed_handler().
   * This handler builds a response packet, which is
   * - an Abort if
   *   - the message is segmented
   *   - if decoding fails
   *   - if the response would be too large
   * - the result from Device_Read_Property(), if it succeeds
   * - an Error if Device_Read_Property() fails
   *   or there isn't enough room in the APDU to fit the data.
   *
   * @param service_request [in] The contents of the service request.
   * @param service_len [in] The length of the service_request.
   * @param src [in] BACNET_ADDRESS of the source of the message
   * @param service_data [in] The BACNET_CONFIRMED_SERVICE_DATA information
   *                          decoded from the APDU header of this message.
   */
  void handler_read_property(
      uint8_t * service_request,
      uint16_t service_len,
      BACNET_ADDRESS * src,
      BACNET_CONFIRMED_SERVICE_DATA * service_data)
  {
      BACNET_READ_PROPERTY_DATA rpdata;
      int len = 0;
      int pdu_len = 0;
      int apdu_len = -1;
      int npdu_len = -1;
      BACNET_NPDU_DATA npdu_data;
      bool error = true;  /* assume that there is an error */
      int bytes_sent = 0;
      BACNET_ADDRESS my_address;
  
      /* configure default error code as an abort since it is common */
      rpdata.error_code = ERROR_CODE_ABORT_SEGMENTATION_NOT_SUPPORTED;
      /* encode the NPDU portion of the packet */
      datalink_get_my_address(&my_address);
      npdu_encode_npdu_data(&npdu_data, false, MESSAGE_PRIORITY_NORMAL);
      npdu_len =
          npdu_encode_pdu(&Handler_Transmit_Buffer[0], src, &my_address,
          &npdu_data);
      if (service_data->segmented_message) {
          /* we don't support segmentation - send an abort */
          len = BACNET_STATUS_ABORT;
  #if PRINT_ENABLED
          fprintf(stderr, "RP: Segmented message.  Sending Abort!\n");
  #endif
          goto RP_FAILURE;
      }
      len = rp_decode_service_request(service_request, service_len, &rpdata);
  #if PRINT_ENABLED
      if (len <= 0) {
          fprintf(stderr, "RP: Unable to decode Request!\n");
      }
  #endif
      if (len < 0) {
          /* bad decoding - skip to error/reject/abort handling */
          error = true;
  #if PRINT_ENABLED
          fprintf(stderr, "RP: Bad Encoding.\n");
  #endif
          goto RP_FAILURE;
      }
      /* Test for case of indefinite Device object instance */
      if ((rpdata.object_type == OBJECT_DEVICE) &&
          (rpdata.object_instance == BACNET_MAX_INSTANCE)) {
          rpdata.object_instance = Device_Object_Instance_Number();
      }
  
      apdu_len =
          rp_ack_encode_apdu_init(&Handler_Transmit_Buffer[npdu_len],
          service_data->invoke_id, &rpdata);
      /* configure our storage */
      rpdata.application_data = &Handler_Transmit_Buffer[npdu_len + apdu_len];
      rpdata.application_data_len =
          sizeof(Handler_Transmit_Buffer) - (npdu_len + apdu_len);
      len = Device_Read_Property(&rpdata);
      if (len >= 0) {
          apdu_len += len;
          len =
              rp_ack_encode_apdu_object_property_end(&Handler_Transmit_Buffer
              [npdu_len + apdu_len]);
          apdu_len += len;
          if (apdu_len > service_data->max_resp) {
              /* too big for the sender - send an abort
               * Setting of error code needed here as read property processing may
               * have overriden the default set at start */
              rpdata.error_code = ERROR_CODE_ABORT_SEGMENTATION_NOT_SUPPORTED;
              len = BACNET_STATUS_ABORT;
  #if PRINT_ENABLED
              fprintf(stderr, "RP: Message too large.\n");
  #endif
          } else {
  #if PRINT_ENABLED
              fprintf(stderr, "RP: Sending Ack!\n");
  #endif
              error = false;
          }
      } else {
  #if PRINT_ENABLED
          fprintf(stderr, "RP: Device_Read_Property: ");
          if (len == BACNET_STATUS_ABORT) {
              fprintf(stderr, "Abort!\n");
          } else if (len == BACNET_STATUS_ERROR) {
              fprintf(stderr, "Error!\n");
          } else if (len == BACNET_STATUS_REJECT) {
              fprintf(stderr, "Reject!\n");
          } else {
              fprintf(stderr, "Unknown Len=%d\n", len);
          }
  #endif
      }
  
    RP_FAILURE:
      if (error) {
          if (len == BACNET_STATUS_ABORT) {
              apdu_len =
                  abort_encode_apdu(&Handler_Transmit_Buffer[npdu_len],
                  service_data->invoke_id,
                  abort_convert_error_code(rpdata.error_code), true);
  #if PRINT_ENABLED
              fprintf(stderr, "RP: Sending Abort!\n");
  #endif
          } else if (len == BACNET_STATUS_ERROR) {
              apdu_len =
                  bacerror_encode_apdu(&Handler_Transmit_Buffer[npdu_len],
                  service_data->invoke_id, SERVICE_CONFIRMED_READ_PROPERTY,
                  rpdata.error_class, rpdata.error_code);
  #if PRINT_ENABLED
              fprintf(stderr, "RP: Sending Error!\n");
  #endif
          } else if (len == BACNET_STATUS_REJECT) {
              apdu_len =
                  reject_encode_apdu(&Handler_Transmit_Buffer[npdu_len],
                  service_data->invoke_id,
                  reject_convert_error_code(rpdata.error_code));
  #if PRINT_ENABLED
              fprintf(stderr, "RP: Sending Reject!\n");
  #endif
          }
      }
  
      pdu_len = npdu_len + apdu_len;
      bytes_sent =
          datalink_send_pdu(src, &npdu_data, &Handler_Transmit_Buffer[0],
          pdu_len);
      if (bytes_sent <= 0) {
  #if PRINT_ENABLED
          fprintf(stderr, "Failed to send PDU (%s)!\n", strerror(errno));
  #endif
      }
  
      return;
  }
  