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 /** FileX Component                                                       */
16 /**                                                                       */
17 /**   Utility                                                             */
18 /**                                                                       */
19 /**************************************************************************/
20 /**************************************************************************/
21 
22 #define FX_SOURCE_CODE
23 
24 
25 /* Include necessary system files.  */
26 
27 #include "fx_api.h"
28 #include "fx_system.h"
29 #include "fx_utility.h"
30 
31 
32 /**************************************************************************/
33 /*                                                                        */
34 /*  FUNCTION                                               RELEASE        */
35 /*                                                                        */
36 /*    _fx_utility_64_unsigned_read                        PORTABLE C      */
37 /*                                                           6.1          */
38 /*  AUTHOR                                                                */
39 /*                                                                        */
40 /*    William E. Lamie, Microsoft Corporation                             */
41 /*                                                                        */
42 /*  DESCRIPTION                                                           */
43 /*                                                                        */
44 /*    This function reads (with endian awareness) a 64-bit unsigned data  */
45 /*    from the specified source and returns the value to the caller.      */
46 /*                                                                        */
47 /*  INPUT                                                                 */
48 /*                                                                        */
49 /*    source_ptr                            Source memory pointer         */
50 /*                                                                        */
51 /*  OUTPUT                                                                */
52 /*                                                                        */
53 /*    ULONG64 value                                                       */
54 /*                                                                        */
55 /*  CALLS                                                                 */
56 /*                                                                        */
57 /*    None                                                                */
58 /*                                                                        */
59 /*  CALLED BY                                                             */
60 /*                                                                        */
61 /*    FileX System Functions                                              */
62 /*                                                                        */
63 /*  RELEASE HISTORY                                                       */
64 /*                                                                        */
65 /*    DATE              NAME                      DESCRIPTION             */
66 /*                                                                        */
67 /*  05-19-2020     William E. Lamie         Initial Version 6.0           */
68 /*  09-30-2020     William E. Lamie         Modified comment(s),          */
69 /*                                            resulting in version 6.1    */
70 /*                                                                        */
71 /**************************************************************************/
_fx_utility_64_unsigned_read(UCHAR * source_ptr)72 ULONG64  _fx_utility_64_unsigned_read(UCHAR *source_ptr)
73 {
74 
75 ULONG64 value;
76 ULONG   upper_portion;
77 ULONG   lower_portion;
78 
79 
80     lower_portion = _fx_utility_32_unsigned_read(source_ptr);
81     upper_portion = _fx_utility_32_unsigned_read(source_ptr + sizeof(ULONG));
82 
83     value =  ((ULONG64)upper_portion) << 32;
84     value |= (ULONG64)lower_portion;
85 
86     /* Return 64-bit value to caller.  */
87     return(value);
88 }
89 
90