//params: room_name
void print_room(char* name){
room_node* target = find_room(name);
if (target == NULL)
return;
printf("=== %s ===\n",name);
print_users(target->users);
print_msgs(target->msgs);
}
int main(int argc, char *argv[])
{
/* Index */
int i;
/* Flags to msgsnd */
int msgsnd_flag = 0;
/* Flags to msgrcv */
int msgrcv_flg = 0;
/* Number of processes to fork() */
int num_procs = 1;
/* String read from input */
char *input = NULL;
/* Placeholder for message type identifier */
long msgtyp_id;
/* Indices of */
int msgtyp_idxs[26];
int *msgtyp_idxs_p = msgtyp_idxs;
/* Struct for use with GNU getopt_long() */
struct option longopts[] = {
{ "number", required_argument, 0, 'n' },
{ 0, 0, 0, 0 }
};
/* Variable to hold flag currently
* being ready by getopt() */
int c;
/* Index of option currently
* being considered */
int opt_index = 0;
if(argc != 1 && argc != 3)
usage(stderr, argv[0], "incorrect number of options", EXIT_FAILURE);
/*
* Loop adapted from example given at
* http://www.gnu.org/software/libc/manual/html_node/Example-of-Getopt.html
*/
while((c = getopt_long(argc, argv, "n:",
longopts, &opt_index)) != -1) {
switch(c) {
case 'n':
num_procs = atoi(optarg);
break;
case('?'):
default:
usage(stderr, argv[0], "unrecognized option", EXIT_FAILURE);
break;
}
}
if(num_procs > MAX_PROCS)
usage(stderr, argv[0], "invalid number of processes", EXIT_FAILURE);
/* One queue each for parent and children */
num_queues = num_procs + 1;
/* Calculate which queue/process a word
* should be assigned to based on its
* first letter */
msgtyp_idx_gen(&msgtyp_idxs_p, num_procs);
/* Allocate space to store pids of
* parent and children */
pids = xmalloc(sizeof(pid_t) * num_queues);
/* Store parent pid */
pids[0] = parent_pid = getpid();
/* Create one key each for parent
* and child processes */
keygen(&keys, num_queues);
/* Create one queue each for parent
* and child processes */
queue_init(&queues, keys, num_queues);
/* Parent queue is first in array */
parent_queue = queues[0];
/* Set up handler for SIGCHLD,
* SIGINT, and SIGTERM */
signal(SIGCHLD, &sig_handler);
signal(SIGINT, &sig_handler);
signal(SIGTERM, &sig_handler);
/* Start subprocesses */
subproc_exec(queues, keys, num_procs);
/* Assign string 'input' a message type that is
* the pid of one of the subprocesses (that's why there's
* a '+ 1' in the array index -- the parent pid is pid[0]). */
while((input = get_word(stdin, BUFLEN)) != NULL) {
msgtyp_id = (long)pids[msgtyp_idxs[input[0] - 97] + 1];
/* Create msg_t from 'input' string and
* place it in parent queue */
if(msgsnd_str(parent_queue, strlen(input) + 1, msgsnd_flag, msgtyp_id, input, 1) == -1) {
perror("main: msgsnd");
clean_up_procs(queues, pids, num_queues);
exit(EXIT_FAILURE);
}
free(input);
}
/* Send terminating message to each child */
for(i = 1; i < num_queues; i++) {
msgtyp_id = (long)pids[i];
if(msgsnd_str(parent_queue, 1, msgsnd_flag, msgtyp_id, "", -1) == -1) {
perror("msgsnd");
clean_up_procs(queues, pids, num_queues);
exit(EXIT_FAILURE);
}
}
/* Print messages received from children
* in alphabetical order */
for(i = 1; i <= num_procs; i++) {
if(print_msgs(queues[i], MSG_SZ, pids[i], msgrcv_flg) == -1) {
perror("main: msgrcv");
clean_up_procs(queues, pids, num_queues);
exit(EXIT_FAILURE);
}
}
/* Wait for children to terminate */
for (i = 0; i < num_procs; i++)
wait(NULL);
/* Free memory and destroy queues */
clean_up_procs(queues, pids, num_queues);
return 0;
}