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 /** User Datagram Protocol (UDP) */ 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_udp.h" 30 31 32 /**************************************************************************/ 33 /* */ 34 /* FUNCTION RELEASE */ 35 /* */ 36 /* _nx_udp_socket_bytes_available PORTABLE C */ 37 /* 6.1 */ 38 /* AUTHOR */ 39 /* */ 40 /* Yuxin Zhou, Microsoft Corporation */ 41 /* */ 42 /* DESCRIPTION */ 43 /* */ 44 /* This function determines the number of bytes available on a UDP */ 45 /* socket for reception. */ 46 /* */ 47 /* INPUT */ 48 /* */ 49 /* socket_ptr Pointer to the UDP sockete */ 50 /* bytes_available Number of bytes returned to */ 51 /* the caller. */ 52 /* */ 53 /* OUTPUT */ 54 /* */ 55 /* status Completion status */ 56 /* */ 57 /* CALLS */ 58 /* */ 59 /* tx_mutex_get Obtain protection */ 60 /* tx_mutex_put Release protection */ 61 /* */ 62 /* CALLED BY */ 63 /* */ 64 /* Application Code */ 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_udp_socket_bytes_available(NX_UDP_SOCKET * socket_ptr,ULONG * bytes_available)75UINT _nx_udp_socket_bytes_available(NX_UDP_SOCKET *socket_ptr, ULONG *bytes_available) 76 { 77 NX_IP *ip_ptr; 78 NX_PACKET *packet_ptr; 79 INT count; 80 81 /* Setup IP pointer. */ 82 ip_ptr = socket_ptr -> nx_udp_socket_ip_ptr; 83 84 /* Obtain the IP mutex so we can examine the bound port. */ 85 tx_mutex_get(&(ip_ptr -> nx_ip_protection), TX_WAIT_FOREVER); 86 87 *bytes_available = 0; 88 89 /* Determine if the socket is currently bound. */ 90 if (!socket_ptr -> nx_udp_socket_bound_next) 91 { 92 /* Release mutex */ 93 tx_mutex_put(&(ip_ptr -> nx_ip_protection)); 94 95 return(NX_NOT_SUCCESSFUL); 96 } 97 98 packet_ptr = socket_ptr -> nx_udp_socket_receive_head; 99 100 /* Loop through all the packets on the queue and find out the total 101 number of bytes in the rx queue that are available to the applciation. */ 102 for (count = 0; count < (INT)(socket_ptr -> nx_udp_socket_receive_count); count++) 103 { 104 105 *bytes_available += (packet_ptr -> nx_packet_length - (ULONG)sizeof(NX_UDP_HEADER)); 106 107 /* Move on to the next packet. */ 108 packet_ptr = packet_ptr -> nx_packet_queue_next; 109 } 110 111 /* Release protection. */ 112 tx_mutex_put(&(ip_ptr -> nx_ip_protection)); 113 114 return(NX_SUCCESS); 115 } 116 117
