cs-3013-assignment-3/mailbox.h

#ifndef MAILBOX_H
#define MAILBOX_H

#include <semaphore.h>

extern struct mailbox *mailboxes;

struct msg {
	// index of thread that sent the message
	// if iFrom is -1, then the message is considered invalid.
	int iFrom;
	// value of message
	int value;
	// number of operations (optional; used to send a message back to the main thread)
	int cnt;
	// total time (optional; used to send a message back to the main thread)
	int tot;
};

struct mailbox {
	// the current message in the mailbox
	struct msg stored_message;
	// represents whether or not a message can be sent
	sem_t send_sem;
	// represents whether or not a message can be receieved
	sem_t recv_sem;
};

int init_mailboxes(int n);
void free_mailboxes();
// God I hate the caps, but this is the required definition.
int SendMsg(int dest, struct msg *message);
int RecvMsg(int mailbox_index, struct msg *message);
int NBSendMsg(int dest, struct msg *message);

#endif