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 /** POSIX wrapper for THREADX                                             */
17 /**                                                                       */
18 /**                                                                       */
19 /**                                                                       */
20 /**************************************************************************/
21 /**************************************************************************/
22 
23 /* Include necessary system files.  */
24 
25 #include "tx_api.h"    /* Threadx API */
26 #include "pthread.h"  /* Posix API */
27 #include "px_int.h"    /* Posix helper functions */
28 
29 
30 /**************************************************************************/
31 /*                                                                        */
32 /*  FUNCTION                                               RELEASE        */
33 /*                                                                        */
34 /*    sem_getvalue                                        PORTABLE C      */
35 /*                                                           6.1.7        */
36 /*  AUTHOR                                                                */
37 /*                                                                        */
38 /*    William E. Lamie, Microsoft Corporation                             */
39 /*                                                                        */
40 /*  DESCRIPTION                                                           */
41 /*                                                                        */
42 /*    This routine updates the location referenced by the sval argument   */
43 /*    to have the value of the semaphore referenced by sem without        */
44 /*    affecting the state of the semaphore                                */
45 /*                                                                        */
46 /*  INPUT                                                                 */
47 /*                                                                        */
48 /*    *sem                  pointer to Semaphore.                         */
49 /*    *sval                 Buffer by which the value is returned.        */
50 /*                                                                        */
51 /*  OUTPUT                                                                */
52 /*                                                                        */
53 /*    OK                    If successful                                 */
54 /*    ERROR                 IF fails                                      */
55 /*                                                                        */
56 /*  CALLS                                                                 */
57 /*                                                                        */
58 /*    None                                                                */
59 /*                                                                        */
60 /*  CALLED BY                                                             */
61 /*                                                                        */
62 /*    Application Code                                                    */
63 /*                                                                        */
64 /*  RELEASE HISTORY                                                       */
65 /*                                                                        */
66 /*    DATE              NAME                      DESCRIPTION             */
67 /*                                                                        */
68 /*  06-02-2021     William E. Lamie         Initial Version 6.1.7         */
69 /*                                                                        */
70 /**************************************************************************/
sem_getvalue(sem_t * sem,ULONG * sval)71 INT sem_getvalue(sem_t * sem,ULONG * sval)
72 {
73 
74 TX_INTERRUPT_SAVE_AREA
75 
76 TX_SEMAPHORE   *TheSem;
77 
78     /* get ThreadX semaphore.  */
79     TheSem = (TX_SEMAPHORE *)sem;
80 
81     /* First, check for an invalid semaphore pointer.  */
82     if ((!TheSem) || (TheSem -> tx_semaphore_id != TX_SEMAPHORE_ID))
83     {
84         /* Return appropriate error.  */
85         posix_errno=EINVAL;
86 	    posix_set_pthread_errno(EINVAL);
87         /* Return Error.  */
88         return(EINVAL);
89     }
90 
91     /* Disable interrupts.  */
92     TX_DISABLE
93 
94     * sval = TheSem ->tx_semaphore_count;
95 
96     /* Restore Interrupts.  */
97     TX_RESTORE
98 
99     return(OK);
100 }
101