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 /** USBX Component */
17 /** */
18 /** Host Stack */
19 /** */
20 /**************************************************************************/
21 /**************************************************************************/
22
23
24 /* Include necessary system files. */
25
26 #define UX_SOURCE_CODE
27
28 #include "ux_api.h"
29 #include "ux_host_stack.h"
30
31
32 /**************************************************************************/
33 /* */
34 /* FUNCTION RELEASE */
35 /* */
36 /* _ux_host_stack_class_get PORTABLE C */
37 /* 6.1 */
38 /* AUTHOR */
39 /* */
40 /* Chaoqiong Xiao, Microsoft Corporation */
41 /* */
42 /* DESCRIPTION */
43 /* */
44 /* This function returns a pointer to the class container. A class */
45 /* needs to obtain its container from the USBX stack to search for */
46 /* instances when a driver or an application wants to open a device. */
47 /* */
48 /* Note: The C string of class_name must be NULL-terminated and the */
49 /* length of it (without the NULL-terminator itself) must be no larger */
50 /* than UX_MAX_CLASS_NAME_LENGTH. */
51 /* */
52 /* INPUT */
53 /* */
54 /* class_name Name of class */
55 /* class Class pointer */
56 /* */
57 /* OUTPUT */
58 /* */
59 /* Completion Status */
60 /* */
61 /* CALLS */
62 /* */
63 /* _ux_utility_string_length_check Check C string and return its */
64 /* length if null-terminated */
65 /* _ux_utility_memory_compare Compare memory blocks */
66 /* */
67 /* CALLED BY */
68 /* */
69 /* Application */
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 /* optimized based on compile */
79 /* definitions, */
80 /* resulting in version 6.1 */
81 /* */
82 /**************************************************************************/
_ux_host_stack_class_get(UCHAR * class_name,UX_HOST_CLASS ** host_class)83 UINT _ux_host_stack_class_get(UCHAR *class_name, UX_HOST_CLASS **host_class)
84 {
85
86 UX_HOST_CLASS *class_ptr;
87 #if !defined(UX_NAME_REFERENCED_BY_POINTER)
88 UINT status;
89 UINT class_name_length = 0;
90 #endif
91 #if UX_MAX_CLASS_DRIVER > 1
92 ULONG class_index;
93 #endif
94
95 #if !defined(UX_NAME_REFERENCED_BY_POINTER)
96 /* Get the length of the class name (exclude null-terminator). */
97 status = _ux_utility_string_length_check(class_name, &class_name_length, UX_MAX_CLASS_NAME_LENGTH);
98 if (status)
99 return(status);
100 #endif
101
102 /* Get first class. */
103 class_ptr = _ux_system_host -> ux_system_host_class_array;
104
105 #if UX_MAX_CLASS_DRIVER > 1
106 /* We need to parse the class driver table. */
107 for (class_index = 0; class_index < _ux_system_host -> ux_system_host_max_class; class_index++)
108 {
109 #endif
110
111 /* Check if this class is already being used. */
112 if (class_ptr -> ux_host_class_status == UX_USED)
113 {
114
115 /* We have found a container. Check if this is the one we need (compare including null-terminator). */
116 if (ux_utility_name_match(class_ptr -> ux_host_class_name, class_name, class_name_length + 1))
117 {
118
119 /* The class container was found. Update the pointer to the class container for the caller. */
120 *host_class = class_ptr;
121
122 /* Return success. */
123 return(UX_SUCCESS);
124 }
125 }
126
127 #if UX_MAX_CLASS_DRIVER > 1
128 /* Move to the next class. */
129 class_ptr++;
130 }
131 #endif
132
133 /* If trace is enabled, insert this event into the trace buffer. */
134 UX_TRACE_IN_LINE_INSERT(UX_TRACE_ERROR, UX_HOST_CLASS_UNKNOWN, class_name, 0, 0, UX_TRACE_ERRORS, 0, 0)
135
136 /* This class does not exist, return an error. */
137 return(UX_HOST_CLASS_UNKNOWN);
138 }
139
140
