seanhalle@0: /* 
seanhalle@0:  * 
seanhalle@0:  */
seanhalle@0: 
seanhalle@0: #include "main.h"
seanhalle@0: #include <pthread.h>
seanhalle@0: 
seanhalle@0: /*
seanhalle@0:  * Consumer.
seanhalle@0:  * 
seanhalle@0:  * Birth function for thread that performs the consumer behavior
seanhalle@0:  * 
seanhalle@0:  *Here's the protocol: 
seanhalle@1:  * Reads a production from the shared Q. 
seanhalle@1:  *   If empty, yields and tries again.
seanhalle@1:  * When has a production from every producer, broadcasts next iter to producers
seanhalle@1:  * When has all the tuples, end
seanhalle@0:  */
seanhalle@0: void* 
seanhalle@0: consumer_birthFn( void* _params )
seanhalle@0:  {
seanhalle@1:    int numProducts;
seanhalle@1:    void *production; //dummy ptr
seanhalle@0:    
seanhalle@0:    ConsumerParams* params = (ConsumerParams *)_params;
seanhalle@0:        
seanhalle@0:    
seanhalle@0:    /*The consumer does two loops.  
seanhalle@0:     * The outside loop counts the number of tuples created.
seanhalle@0:     * The inside loop collects the products for one tuple.
seanhalle@0:     * 
seanhalle@0:     *Protocol:
seanhalle@0:     * increment tupleIter
seanhalle@0:     * wake producers for next tuple
seanhalle@1:     * Reads a production from the shared Q. 
seanhalle@1:     *   If empty, yields and tries again.
seanhalle@1:     * if more productions in tuple, repeat
seanhalle@1:     * if have more tuples, repeat
seanhalle@1:     * end thread
seanhalle@0:     */
seanhalle@0:    while( tupleIter < params->numTuplesToCreate )
seanhalle@0:     {
seanhalle@1:       if( tupleIter % 1000 == 0 ) DEBUG__printf1("tuples produced: %d\n", tupleIter);
seanhalle@1:        
seanhalle@1:       // wake producers for next iter
seanhalle@0:       DEBUG__printf("consumer broadcast for next iter\n");
seanhalle@0:       pthread_mutex_lock(&tupleIterLock);
seanhalle@1:       tupleIter += 1; // increment tupleIter (global shared)
seanhalle@0:       pthread_cond_broadcast( &tupleIterCond );
seanhalle@0:       pthread_mutex_unlock(&tupleIterLock);
seanhalle@0:          
seanhalle@0:       for( numProducts = 0; numProducts < params->numProducers; numProducts++ )
seanhalle@0:        { 
seanhalle@1:          // read a production from the shared Q.
seanhalle@1:          production = NULL;
seanhalle@1:          while( production == NULL )
seanhalle@1:           { pthread_mutex_lock( &queueAccessLock );
seanhalle@1:             production = readPrivQ( commQ );
seanhalle@1:             pthread_mutex_unlock( &queueAccessLock );
seanhalle@1:             // If empty, yields and tries again.
seanhalle@1:             if( production == NULL) sched_yield();
seanhalle@0:           }
seanhalle@0:          DEBUG__printf1( "consumer got production %d\n", currProductionNum );
seanhalle@1:        } //if more productions for current tuple, repeat
seanhalle@0:     
seanhalle@0:       // have all productions for current tuple, so add tuple to output
seanhalle@0:       //add tuple to output and malloc new tuple array -- overhead meas, do nothing
seanhalle@0:       
seanhalle@0:     } // if have all tuples are going to produce, end
seanhalle@0: 
seanhalle@0:    //Shutdown consumer thread
seanhalle@0:    pthread_exit(NULL);
seanhalle@0:     
seanhalle@0:  }
seanhalle@0: