// Common usage() prints out stuff for command-line help void usage() { fprintf(stderr, "usage: \n"); fprintf(stderr, " -l \n"); fprintf(stderr, " -m \n"); fprintf(stderr, " -p \n"); fprintf(stderr, " -c \n"); fprintf(stderr, " -P \n"); fprintf(stderr, " -C \n"); fprintf(stderr, " -v [ verbose flag: trace what is happening and print it ]\n"); fprintf(stderr, " -t [ timing flag: time entire execution and print total time ]\n"); exit(1); } // Common main() for all four programs // - Does arg parsing // - Starts producers and consumers // - Once producers are finished, puts END_OF_STREAM // marker into shared queue to signal end to consumers // - Then waits for consumers and prints some final info int main(int argc, char *argv[]) { loops = 1; max = 1; consumers = 1; producers = 1; char *producer_pause_string = NULL; char *consumer_pause_string = NULL; opterr = 0; int c; while ((c = getopt (argc, argv, "l:m:p:c:P:C:vt")) != -1) { switch (c) { case 'l': loops = atoi(optarg); break; case 'm': max = atoi(optarg); break; case 'p': producers = atoi(optarg); break; case 'c': consumers = atoi(optarg); break; case 'P': producer_pause_string = optarg; break; case 'C': consumer_pause_string = optarg; break; case 'v': do_trace = 1; break; case 't': do_timing = 1; break; default: usage(); } } assert(loops > 0); assert(max > 0); assert(producers <= MAX_THREADS); assert(consumers <= MAX_THREADS); if (producer_pause_string != NULL) parse_pause_string(producer_pause_string, "producers", producers, producer_pause_times); if (consumer_pause_string != NULL) parse_pause_string(consumer_pause_string, "consumers", consumers, consumer_pause_times); // make space for shared buffer, and init it ... buffer = (int *) Malloc(max * sizeof(int)); int i; for (i = 0; i < max; i++) { buffer[i] = EMPTY; } do_print_headers(); double t1 = Time_GetSeconds(); // start up all threads; order doesn't matter here pthread_t pid[MAX_THREADS], cid[MAX_THREADS]; int thread_id = 0; for (i = 0; i < producers; i++) { Pthread_create(&pid[i], NULL, producer, (void *) (long long) thread_id); thread_id++; } for (i = 0; i < consumers; i++) { Pthread_create(&cid[i], NULL, consumer, (void *) (long long) thread_id); thread_id++; } // now wait for all PRODUCERS to finish for (i = 0; i < producers; i++) { Pthread_join(pid[i], NULL); } // end case: when producers are all done // - put "consumers" number of END_OF_STREAM's in queue // - when consumer sees -1, it exits for (i = 0; i < consumers; i++) { Mutex_lock(&m); while (num_full == max) Cond_wait(empty_cv, &m); do_fill(END_OF_STREAM); do_eos(); Cond_signal(fill_cv); Mutex_unlock(&m); } // now OK to wait for all consumers int counts[consumers]; for (i = 0; i < consumers; i++) { Pthread_join(cid[i], (void *) &counts[i]); } double t2 = Time_GetSeconds(); if (do_trace) { printf("\nConsumer consumption:\n"); for (i = 0; i < consumers; i++) { printf(" C%d -> %d\n", i, counts[i]); } printf("\n"); } if (do_timing) { printf("Total time: %.2f seconds\n", t2-t1); } return 0; }

Exercise