1 /**************************************************************************/ 2 /* */ 3 /* Copyright (c) Microsoft Corporation. All rights reserved. */ 4 /* */ 5 /* This software is licensed under the Microsoft Software License */ 6 /* Terms for Microsoft Azure RTOS. Full text of the license can be */ 7 /* found in the LICENSE file at https://aka.ms/AzureRTOS_EULA */ 8 /* and in the root directory of this software. */ 9 /* */ 10 /**************************************************************************/ 11 12 13 /**************************************************************************/ 14 /**************************************************************************/ 15 /** */ 16 /** NetX Component */ 17 /** */ 18 /** Transmission Control Protocol (TCP) */ 19 /** */ 20 /**************************************************************************/ 21 /**************************************************************************/ 22 23 #define NX_SOURCE_CODE 24 25 26 /* Include necessary system files. */ 27 28 #include "nx_api.h" 29 #include "nx_tcp.h" 30 #include "nx_ipv6.h" 31 32 /**************************************************************************/ 33 /* */ 34 /* FUNCTION RELEASE */ 35 /* */ 36 /* _nx_tcp_socket_state_last_ack PORTABLE C */ 37 /* 6.1 */ 38 /* AUTHOR */ 39 /* */ 40 /* Yuxin Zhou, Microsoft Corporation */ 41 /* */ 42 /* DESCRIPTION */ 43 /* */ 44 /* This function processes packets during the LAST ACK state, */ 45 /* which is the state at the end of a passive disconnect, i.e. a */ 46 /* disconnect issued by the other side of the connection. */ 47 /* */ 48 /* INPUT */ 49 /* */ 50 /* socket_ptr Pointer to owning socket */ 51 /* tcp_header_ptr Pointer to packet header */ 52 /* */ 53 /* OUTPUT */ 54 /* */ 55 /* None */ 56 /* */ 57 /* CALLS */ 58 /* */ 59 /* _nx_tcp_socket_thread_resume Resume suspended thread */ 60 /* _nx_tcp_socket_block_cleanup Cleanup the socket block */ 61 /* */ 62 /* CALLED BY */ 63 /* */ 64 /* _nx_tcp_socket_packet_process Process TCP packet for socket */ 65 /* */ 66 /* RELEASE HISTORY */ 67 /* */ 68 /* DATE NAME DESCRIPTION */ 69 /* */ 70 /* 05-19-2020 Yuxin Zhou Initial Version 6.0 */ 71 /* 09-30-2020 Yuxin Zhou Modified comment(s), */ 72 /* resulting in version 6.1 */ 73 /* */ 74 /**************************************************************************/ _nx_tcp_socket_state_last_ack(NX_TCP_SOCKET * socket_ptr,NX_TCP_HEADER * tcp_header_ptr)75VOID _nx_tcp_socket_state_last_ack(NX_TCP_SOCKET *socket_ptr, NX_TCP_HEADER *tcp_header_ptr) 76 { 77 78 /* Determine if the incoming message is an ACK message. */ 79 if (tcp_header_ptr -> nx_tcp_header_word_3 & NX_TCP_ACK_BIT) 80 { 81 82 /* If it is proper, finish the disconnect. */ 83 if ((tcp_header_ptr -> nx_tcp_acknowledgment_number == socket_ptr -> nx_tcp_socket_tx_sequence) && 84 (tcp_header_ptr -> nx_tcp_sequence_number == socket_ptr -> nx_tcp_socket_rx_sequence)) 85 { 86 87 /* Cleanup the transmission control block. */ 88 _nx_tcp_socket_block_cleanup(socket_ptr); 89 90 /* Determine if we need to wake a thread suspended on the disconnection. */ 91 if (socket_ptr -> nx_tcp_socket_disconnect_suspended_thread) 92 { 93 94 /* Resume suspended thread. */ 95 _nx_tcp_socket_thread_resume(&(socket_ptr -> nx_tcp_socket_disconnect_suspended_thread), NX_SUCCESS); 96 } 97 98 #ifndef NX_DISABLE_EXTENDED_NOTIFY_SUPPORT 99 100 /* Is a disconnect callback registered with the TCP socket? */ 101 if (socket_ptr -> nx_tcp_disconnect_complete_notify) 102 { 103 104 /* Call the application's disconnect_complete callback function. */ 105 (socket_ptr -> nx_tcp_disconnect_complete_notify)(socket_ptr); 106 } 107 #endif 108 } 109 } 110 } 111 112
