Home | History | Annotate | Download | only in src 
      1 /*--------------------------------------------------------------------------
      2 Copyright (c) 2010-2013, The Linux Foundation. All rights reserved.
      3 
      4 Redistribution and use in source and binary forms, with or without
      5 modification, are permitted provided that the following conditions are met:
      6     * Redistributions of source code must retain the above copyright
      7       notice, this list of conditions and the following disclaimer.
      8     * Redistributions in binary form must reproduce the above copyright
      9       notice, this list of conditions and the following disclaimer in the
     10       documentation and/or other materials provided with the distribution.
     11     * Neither the name of The Linux Foundation nor
     12       the names of its contributors may be used to endorse or promote
     13       products derived from this software without specific prior written
     14       permission.
     15 
     16 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
     17 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     18 IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
     19 NON-INFRINGEMENT ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
     20 CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
     21 EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
     22 PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
     23 OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
     24 WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
     25 OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
     26 ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     27 --------------------------------------------------------------------------*/
     28 #include "message_queue.h"
     29 
     30 int check_if_queue_empty ( unsigned int queuetocheck, void* queuecontext )
     31 {
     32     struct video_queue_context *ptr_q = NULL;
     33 
     34     /*
     35      * queuetocheck - 0 command queue
     36      * queuetocheck - 1 data queue
     37      */
     38     if ( queuecontext == NULL || (queuetocheck > 1 ) ) {
     39         return 1;
     40     }
     41 
     42     ptr_q = (struct video_queue_context *)queuecontext;
     43 
     44     if (queuetocheck == 0) {
     45         if (ptr_q->read_comq == ptr_q->write_comq) {
     46             return 1;
     47         }
     48     } else if (queuetocheck == 1) {
     49         if (ptr_q->write_dataq == ptr_q->read_dataq) {
     50             return 1;
     51         }
     52     }
     53 
     54     return 0;
     55 }
     56 
     57 
     58 
     59 struct video_msgq * queue_get_cmd (void* queuecontext ) {
     60     struct video_queue_context *ptr_q = NULL;
     61     struct video_msgq *pitem = NULL;
     62 
     63     if ( NULL == queuecontext ) {
     64         printf("queue_get_cmd: Invalid Input parameter");
     65         return NULL;
     66     }
     67 
     68     ptr_q = (struct video_queue_context *)queuecontext;
     69 
     70     /* Wait on the semaphore till it is released */
     71     sem_wait(&ptr_q->sem_message);
     72 
     73     /* Lock the mutex to protect the critical section */
     74     pthread_mutex_lock(&ptr_q->mutex);
     75 
     76     if (ptr_q->read_comq != ptr_q->write_comq) {
     77         pitem = &ptr_q->ptr_cmdq [ptr_q->read_comq];
     78         ptr_q->read_comq = (ptr_q->read_comq + 1) % \
     79                    ptr_q->commandq_size;
     80     } else if (ptr_q->write_dataq != ptr_q->read_dataq) {
     81         pitem = &ptr_q->ptr_dataq [ptr_q->read_dataq];
     82         ptr_q->read_dataq = (ptr_q->read_dataq + 1) % \
     83                     ptr_q->dataq_size;
     84     }
     85 
     86     /* Unlock the mutex to release the critical section */
     87     pthread_mutex_unlock(&ptr_q->mutex);
     88 
     89     return pitem;
     90 }
     91 
     92 
     93 int queue_post_cmdq ( void* queuecontext,
     94         struct video_msgq *pitem
     95         )
     96 {
     97     struct video_queue_context *ptr_q = NULL;
     98 
     99     if (pitem == NULL || queuecontext == NULL) {
    100         return -1;
    101     }
    102 
    103     ptr_q = (struct video_queue_context *)queuecontext;
    104 
    105     /* Lock the mutex to protect the critical section */
    106     pthread_mutex_lock(&ptr_q->mutex);
    107 
    108     if ((ptr_q->write_comq + 1) % ptr_q->commandq_size == ptr_q->read_comq) {
    109         printf("QUEUE is FULL");
    110         /* Unlock the mutex to release the critical section */
    111         pthread_mutex_unlock(&ptr_q->mutex);
    112         return 0;
    113     } else {
    114         /* Store the command in the Message Queue & increment write offset */
    115         memcpy ( &ptr_q->ptr_cmdq [ptr_q->write_comq],pitem, \
    116                 sizeof (struct video_msgq));
    117         ptr_q->write_comq = (ptr_q->write_comq + 1) % ptr_q->commandq_size;
    118     }
    119 
    120     /* Unlock the mutex to release the critical section */
    121     pthread_mutex_unlock(&ptr_q->mutex);
    122 
    123     /* Post the semaphore */
    124     sem_post(&ptr_q->sem_message);
    125     return 1;
    126 }
    127 
    128 
    129 int queue_post_dataq ( void *queuecontext,
    130         struct video_msgq *pitem
    131         )
    132 {
    133     struct video_queue_context *ptr_q = NULL;
    134 
    135     if (pitem == NULL || queuecontext == NULL) {
    136         return -1;
    137     }
    138 
    139     ptr_q = (struct video_queue_context *)queuecontext;
    140 
    141     /* Lock the mutex to protect the critical section */
    142     pthread_mutex_lock(&ptr_q->mutex);
    143 
    144     if ((ptr_q->write_dataq + 1) % ptr_q->dataq_size == ptr_q->read_dataq) {
    145         printf("QUEUE is FULL");
    146         /* Unlock the mutex to release the critical section */
    147         pthread_mutex_unlock(&ptr_q->mutex);
    148         return 0;
    149     } else {
    150         /* Store the command in the Message Queue & increment write offset */
    151         memcpy ( &ptr_q->ptr_dataq [ptr_q->write_dataq],pitem, \
    152                 sizeof (struct video_msgq));
    153         ptr_q->write_dataq = (ptr_q->write_dataq + 1) % ptr_q->dataq_size;
    154     }
    155 
    156     /* Unlock the mutex to release the critical section */
    157     pthread_mutex_unlock(&ptr_q->mutex);
    158 
    159     /* Post the semaphore */
    160     sem_post(&ptr_q->sem_message);
    161     return 1;
    162 
    163 }
    164