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 /**   Fault Tolerant                                                      */
18 /**                                                                       */
19 /**************************************************************************/
20 /**************************************************************************/
21 
22 #define FX_SOURCE_CODE
23 
24 #include "fx_api.h"
25 #include "fx_fault_tolerant.h"
26 
27 
28 #ifdef FX_ENABLE_FAULT_TOLERANT
29 /**************************************************************************/
30 /*                                                                        */
31 /*  FUNCTION                                               RELEASE        */
32 /*                                                                        */
33 /*    _fx_fault_tolerant_transaction_start                PORTABLE C      */
34 /*                                                           6.1          */
35 /*  AUTHOR                                                                */
36 /*                                                                        */
37 /*    William E. Lamie, Microsoft Corporation                             */
38 /*                                                                        */
39 /*  DESCRIPTION                                                           */
40 /*                                                                        */
41 /*    This function is called at the beginning of an update to FileX      */
42 /*    file, directory entry, or FAT table.  It resets fault tolerant      */
43 /*    internal state information.                                         */
44 /*                                                                        */
45 /*  INPUT                                                                 */
46 /*                                                                        */
47 /*    media_ptr                             Media control block pointer   */
48 /*                                                                        */
49 /*  OUTPUT                                                                */
50 /*                                                                        */
51 /*    return status                                                       */
52 /*                                                                        */
53 /*  CALLS                                                                 */
54 /*                                                                        */
55 /*    None                                                                */
56 /*                                                                        */
57 /*  CALLED BY                                                             */
58 /*                                                                        */
59 /*    _fx_directory_attributes_set                                        */
60 /*    _fx_directory_create                                                */
61 /*    _fx_directory_delete                                                */
62 /*    _fx_directory_rename                                                */
63 /*    _fx_file_allocate                                                   */
64 /*    _fx_file_attributes_set                                             */
65 /*    _fx_file_best_effort_allocate                                       */
66 /*    _fx_file_create                                                     */
67 /*    _fx_file_delete                                                     */
68 /*    _fx_file_rename                                                     */
69 /*    _fx_file_truncate                                                   */
70 /*    _fx_file_truncate_release                                           */
71 /*    _fx_file_write                                                      */
72 /*    _fx_unicode_directory_create                                        */
73 /*    _fx_unicode_file_create                                             */
74 /*                                                                        */
75 /*  RELEASE HISTORY                                                       */
76 /*                                                                        */
77 /*    DATE              NAME                      DESCRIPTION             */
78 /*                                                                        */
79 /*  05-19-2020     William E. Lamie         Initial Version 6.0           */
80 /*  09-30-2020     William E. Lamie         Modified comment(s),          */
81 /*                                            resulting in version 6.1    */
82 /*                                                                        */
83 /**************************************************************************/
_fx_fault_tolerant_transaction_start(FX_MEDIA * media_ptr)84 UINT    _fx_fault_tolerant_transaction_start(FX_MEDIA *media_ptr)
85 {
86 
87     /* Is fault tolerant enabled? */
88     if (media_ptr -> fx_media_fault_tolerant_enabled == FX_TRUE)
89     {
90 
91         /* Is this a new transaction? */
92         if (media_ptr -> fx_media_fault_tolerant_transaction_count == 0)
93         {
94 
95             /* Yes. Initialize data. */
96             media_ptr -> fx_media_fault_tolerant_file_size = FX_FAULT_TOLERANT_LOG_HEADER_SIZE +
97                                                              FX_FAULT_TOLERANT_FAT_CHAIN_SIZE +
98                                                              FX_FAULT_TOLERANT_LOG_CONTENT_HEADER_SIZE;
99 
100             /* Reset total logs. */
101             media_ptr -> fx_media_fault_tolerant_total_logs = 0;
102 
103             /* Set state of fault tolerant. */
104             media_ptr -> fx_media_fault_tolerant_state = FX_FAULT_TOLERANT_STATE_STARTED;
105         }
106 
107         /* Increase the transaction. */
108         media_ptr -> fx_media_fault_tolerant_transaction_count++;
109     }
110 
111     return(FX_SUCCESS);
112 }
113 #endif /* FX_ENABLE_FAULT_TOLERANT */
114 
115