tinyQ.c

00001 #include "string.h"
00002 #include "tinyQ.h"
00003 
00004 
00005 
00006 /**
00007  * \brief Push an Accessibility Event onto our queue for sending to the iphone
00008  * \param q pointer to our tinyQ_t
00009  * \param c the Event to send to the iphone
00010  * \return null if Q full,  1 on success
00011  * \sa Qpop(), Qjump()
00012  * \ingroup tinyQ
00013  */
00014 int Qpush( tinyQ_t* q, char c )
00015 {
00016    if ( q->fill == Q_SIZE )
00017     return 0;
00018     
00019    __disable_irq();
00020    q->fill++;
00021    q->data[q->head++] = c;
00022    __enable_irq();
00023    
00024    return 1;
00025 }
00026 
00027 
00028 /**
00029  * \brief Pop an Accessibility Event off our queue for sending to the iphone
00030  * \param q pointer to our tinyQ_t
00031  * \param c pointer to receive the Event
00032  * \return null if Q empty, 1 on success
00033  * \sa Qpop(), Qjump()
00034  * \ingroup tinyQ
00035  */
00036  int Qpop( tinyQ_t* q, char * c)
00037 {
00038    if (! q->fill )
00039       return 0;
00040       
00041    __disable_irq();
00042    q->fill--;
00043    *c = q->data[q->tail++];
00044    __enable_irq();
00045    
00046    return 1;
00047 }
00048 
00049 int Qfree( tinyQ_t* q )
00050 {
00051     return (Q_SIZE - q->fill);
00052 }
00053 
00054 void Qinit( tinyQ_t * q )
00055 {
00056     memset( q, 0, sizeof(q) );
00057 }