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 /** USBX Component */
16 /** */
17 /** Utility */
18 /** */
19 /**************************************************************************/
20 /**************************************************************************/
21
22
23 /* Include necessary system files. */
24
25 #define UX_SOURCE_CODE
26
27 #include "ux_api.h"
28
29
30 /**************************************************************************/
31 /* */
32 /* FUNCTION RELEASE */
33 /* */
34 /* _ux_utility_string_length_check PORTABLE C */
35 /* 6.1.12 */
36 /* AUTHOR */
37 /* */
38 /* Chaoqiong Xiao, Microsoft Corporation */
39 /* */
40 /* DESCRIPTION */
41 /* */
42 /* This function checks if a NULL-terminated C string reaches its end */
43 /* before specified length exceeds. */
44 /* */
45 /* On success the actual length of C string is written back to UINT */
46 /* variable pointed by string_length_ptr (if not NULL). */
47 /* Otherwise the variable keeps untouched. */
48 /* */
49 /* Note NULL terminator is not counted in string length */
50 /* (same as C strlen). */
51 /* */
52 /* INPUT */
53 /* */
54 /* string Pointer to string */
55 /* string_length_ptr Pointer to UINT to receive */
56 /* the string length */
57 /* max_string_length Max string length */
58 /* */
59 /* OUTPUT */
60 /* */
61 /* returns success if the string length was less than the max length, */
62 /* else it returns error */
63 /* */
64 /* CALLS */
65 /* */
66 /* None */
67 /* */
68 /* CALLED BY */
69 /* */
70 /* USBX Components */
71 /* */
72 /* RELEASE HISTORY */
73 /* */
74 /* DATE NAME DESCRIPTION */
75 /* */
76 /* 05-19-2020 Chaoqiong Xiao Initial Version 6.0 */
77 /* 09-30-2020 Chaoqiong Xiao Modified comment(s), */
78 /* resulting in version 6.1 */
79 /* 07-29-2022 Chaoqiong Xiao Modified comment(s), */
80 /* resulting in version 6.1.12 */
81 /* */
82 /**************************************************************************/
_ux_utility_string_length_check(UCHAR * string,UINT * string_length_ptr,UINT max_string_length)83 UINT _ux_utility_string_length_check(UCHAR *string, UINT *string_length_ptr, UINT max_string_length)
84 {
85
86 UINT string_length;
87
88
89 if (string == UX_NULL)
90 return(UX_ERROR);
91
92 string_length = 0;
93
94 while (1)
95 {
96
97 if (string[string_length] == '\0')
98 break;
99
100 string_length++;
101 if (string_length > max_string_length)
102 {
103
104 /* Error trap. */
105 _ux_system_error_handler(UX_SYSTEM_LEVEL_THREAD, UX_SYSTEM_CONTEXT_UTILITY, UX_ERROR);
106
107 return(UX_ERROR);
108 }
109 }
110
111 if (string_length_ptr)
112 *string_length_ptr = string_length;
113
114 return(UX_SUCCESS);
115 }
116
117
