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 /*    posix_priority_search                               PORTABLE C      */
35 /*                                                           6.2.0        */
36 /*  AUTHOR                                                                */
37 /*                                                                        */
38 /*    William E. Lamie, Microsoft Corporation                             */
39 /*                                                                        */
40 /*  DESCRIPTION                                                           */
41 /*                                                                        */
42 /*    This routine returns the no. of messages of the same priority       */
43 /*    in the message queue.                                               */
44 /*                                                                        */
45 /*  INPUT                                                                 */
46 /*                                                                        */
47 /*    msgQId                 message queue ID                             */
48 /*    priority               priority of the message                      */
49 /*                                                                        */
50 /*  OUTPUT                                                                */
51 /*                                                                        */
52 /*    order                  Returns the number of same priority messages.*/
53 /*                                                                        */
54 /*  CALLS                                                                 */
55 /*                                                                        */
56 /*    None                                                                */
57 /*                                                                        */
58 /*  CALLED BY                                                             */
59 /*                                                                        */
60 /*    POSIX internal Code                                                 */
61 /*                                                                        */
62 /*  RELEASE HISTORY                                                       */
63 /*                                                                        */
64 /*    DATE              NAME                      DESCRIPTION             */
65 /*                                                                        */
66 /*  06-02-2021      William E. Lamie        Initial Version 6.1.7         */
67 /*  10-31-2022      Scott Larson            Add 64-bit support,           */
68 /*                                            resulting in version 6.2.0  */
69 /*                                                                        */
70 /**************************************************************************/
posix_priority_search(mqd_t msgQId,ULONG priority)71 ULONG posix_priority_search(mqd_t msgQId, ULONG priority)
72 {
73 
74 TX_QUEUE            *queue;
75 POSIX_MSG_QUEUE     *q_ptr;
76 ULONG                order = 1;
77 ULONG                numMsgs;
78 UINT                 index;
79 ULONG               *source;
80 ULONG                msgp;
81 
82     queue   = &(msgQId->f_data->queue);
83     q_ptr   = (POSIX_MSG_QUEUE * )queue;
84 
85     /* No. of messages in the queue.  */
86     numMsgs = q_ptr -> queue.tx_queue_enqueued;
87 
88     /* retrieving the message pointer.  */
89     source  =  q_ptr->queue.tx_queue_read;
90 
91     /* check for same priority.  */
92     for(index = 0; index < numMsgs; index++)
93     {
94         source += TX_POSIX_QUEUE_PRIORITY_OFFSET;
95         msgp = *source;
96         source += (TX_POSIX_MESSAGE_SIZE - TX_POSIX_QUEUE_PRIORITY_OFFSET);
97 
98         /* If we're at end of queue, go to start. */
99         if(source == q_ptr->queue.tx_queue_end)
100             source = q_ptr->queue.tx_queue_start;
101 
102         /* Increment priority count. */
103         if(priority == msgp)
104             order += 1;
105     }
106 
107     /* Return the number of same priority messages. */
108     return(order);
109 }
110