1 /***************************************************************************
2  * Copyright (c) 2024 Microsoft Corporation
3  *
4  * This program and the accompanying materials are made available under the
5  * terms of the MIT License which is available at
6  * https://opensource.org/licenses/MIT.
7  *
8  * SPDX-License-Identifier: MIT
9  **************************************************************************/
10 
11 
12 /**************************************************************************/
13 /**************************************************************************/
14 /**                                                                       */
15 /** NetX Component                                                        */
16 /**                                                                       */
17 /**   Transmission Control Protocol (TCP)                                 */
18 /**                                                                       */
19 /**************************************************************************/
20 /**************************************************************************/
21 
22 #define NX_SOURCE_CODE
23 
24 
25 /* Include necessary system files.  */
26 
27 #include "nx_api.h"
28 #include "nx_tcp.h"
29 
30 
31 /* Bring in externs for caller checking code.  */
32 
33 NX_CALLER_CHECKING_EXTERNS
34 
35 
36 /**************************************************************************/
37 /*                                                                        */
38 /*  FUNCTION                                               RELEASE        */
39 /*                                                                        */
40 /*    _nxe_tcp_socket_bytes_available                     PORTABLE C      */
41 /*                                                           6.1          */
42 /*  AUTHOR                                                                */
43 /*                                                                        */
44 /*    Yuxin Zhou, Microsoft Corporation                                   */
45 /*                                                                        */
46 /*  DESCRIPTION                                                           */
47 /*                                                                        */
48 /*    This function checks for errors in the TCP socket bytes             */
49 /*    available function call.                                            */
50 /*                                                                        */
51 /*  INPUT                                                                 */
52 /*                                                                        */
53 /*    socket_ptr                            Pointer to socket             */
54 /*    bytes_available                       Pointer to bytes available    */
55 /*                                                                        */
56 /*  OUTPUT                                                                */
57 /*                                                                        */
58 /*    status                                Completion status             */
59 /*                                                                        */
60 /*  CALLS                                                                 */
61 /*                                                                        */
62 /*    _nx_tcp_socket_bytes_available        Actual TCP socket bytes       */
63 /*                                            available function          */
64 /*                                                                        */
65 /*  CALLED BY                                                             */
66 /*                                                                        */
67 /*    Application                                                         */
68 /*                                                                        */
69 /*  RELEASE HISTORY                                                       */
70 /*                                                                        */
71 /*    DATE              NAME                      DESCRIPTION             */
72 /*                                                                        */
73 /*  05-19-2020     Yuxin Zhou               Initial Version 6.0           */
74 /*  09-30-2020     Yuxin Zhou               Modified comment(s),          */
75 /*                                            resulting in version 6.1    */
76 /*                                                                        */
77 /**************************************************************************/
_nxe_tcp_socket_bytes_available(NX_TCP_SOCKET * socket_ptr,ULONG * bytes_available)78 UINT  _nxe_tcp_socket_bytes_available(NX_TCP_SOCKET *socket_ptr, ULONG *bytes_available)
79 {
80 
81 UINT status;
82 
83 
84     /* Check for invalid input pointers.  */
85     if ((socket_ptr == NX_NULL) ||
86         (socket_ptr -> nx_tcp_socket_id != NX_TCP_ID) ||
87         (bytes_available == NX_NULL))
88     {
89         return(NX_PTR_ERROR);
90     }
91 
92     /* Check to see if TCP is enabled.  */
93     if (!(socket_ptr -> nx_tcp_socket_ip_ptr) -> nx_ip_tcp_packet_receive)
94     {
95         return(NX_NOT_ENABLED);
96     }
97 
98     /* Check for appropriate caller.  */
99     NX_THREADS_ONLY_CALLER_CHECKING
100 
101     /* Call actual TCP socket receive function.  */
102     status =  _nx_tcp_socket_bytes_available(socket_ptr, bytes_available);
103 
104     /* Return completion status.  */
105     return(status);
106 }
107 
108