int send(const char* filename)
{
int flagid = 0;
int master_sender = is_sender(&flagid);
if (!master_sender)
exit(EXIT_SUCCESS);
int shmemid = 0;
void* smbuf = get_memptr( FILE_NAME_SHMEM_ATTACH,
BUF_SIZE + sizeof(long),
&shmemid);
CHECK(smbuf != (void*)-1, "Failed to get shared memory pointer");
long* nbytes_to_save = smbuf + BUF_SIZE;
*nbytes_to_save = 0;
CHECK(smbuf != (void*)-1, "Failed to get memory pointer");
int semid = get_sems( FILE_NAME_SHMEM_ATTACH, 5);
CHECK(semid != -1, "Failed to get semaphors id");
int cond = snd_protect_connection(semid);
CHECK(cond == 0, "Failed to set up protected connection");
int fileid = open(filename, O_RDONLY);
CHECK(fileid != -1, "Failed to open file to send");
struct sembuf rcv_activate[2] = {
{RCV_MUTEX, 1, 0},
{RCV_CONNECT, 1, 0}
};
cond = semop(semid, rcv_activate, 2);
CHECK(cond != -1, "Failed to connect to receiver");
struct sembuf mutexes[3] = {
{SND_MUTEX, 1, 0},
{RCV_MUTEX, -1, 0},
{SND_MUTEX, 0, 0}
};
int nbytes = 0;
while ((nbytes = read(fileid, smbuf, BUF_SIZE)) > 0)
{
*nbytes_to_save = nbytes;
OUT("# Sending\n");
cond = semop(semid, &mutexes[0], 1);
cond = semop(semid, &mutexes[1], 1);
cond = semop(semid, &mutexes[2], 1);
CHECK(cond == 0, "# Failed to set semaphors");
OUT("# Package sent\n");
}
OUT("# Finishing...\n");
*nbytes_to_save = -1;
cond = semop(semid, &mutexes[0], 1);
cond = semop(semid, &mutexes[1], 1);
cond = semop(semid, &mutexes[2], 1);
OUT("# Finished!\n");
cond = snd_clean(semid, fileid, shmemid, flagid);
exit(EXIT_SUCCESS);
}
int receive()
{
int flagid = 0;
int master_receiver = is_receiver(&flagid);
if (!master_receiver)
exit(EXIT_SUCCESS);
int semid = get_sems( FILE_NAME_SHMEM_ATTACH, 5);
CHECK(semid != -1, "Failed to get semaphors id");
int cond = rcv_protect_connection(semid);
CHECK(cond == 0, "Failed to set up protected connection");
int shmemid = 0;
void* smbuf = get_memptr( FILE_NAME_SHMEM_ATTACH,
BUF_SIZE + sizeof(long),
&shmemid);
CHECK(smbuf != (void*)-1, "Failed to get shared memory pointer");
struct sembuf activate = {RCV_CONNECT, -1, 0};
cond = semop(semid, &activate, 1);
OUT("# Activated\n");
struct sembuf mutexes[3] = {
{SND_MUTEX, -1, 0},
{RCV_MUTEX, 1, 0},
{RCV_MUTEX, 0, 0}
};
long* nbytes_to_save = smbuf + BUF_SIZE;
cond = semop(semid, &mutexes[2], 1);
CHECK(cond == 0, "Failed to set semaphors");
while (*nbytes_to_save != -1)
{
OUT1("# Printing %ld bytes\n", *nbytes_to_save);
cond = write(STDOUT_FILENO, smbuf, *nbytes_to_save);
if (cond != *nbytes_to_save)
fprintf(stderr, "Printed = %d\nExpected = %ld\n", cond, *nbytes_to_save);
CHECK(cond == *nbytes_to_save, "Printed ammount of bytes isn't valid");
OUT("# Getting...\n");
cond = semop(semid, &mutexes[1], 1);
cond = semop(semid, &mutexes[0], 1);
OUT1("# Current SND_MUTEX is %d\n", semctl(semid, SND_MUTEX, GETVAL));
OUT1("# Current RCV_MUTEX is %d\n", semctl(semid, RCV_MUTEX, GETVAL));
cond = semop(semid, &mutexes[2], 1);
OUT("# Got package\n");
CHECK(cond == 0, "Failed to set semaphors");
};
OUT("# Finishing receiving\n");
semop(semid, &mutexes[0], 1);
unlink(RCV_FLAG);
semctl(flagid, 0, IPC_RMID);
exit(EXIT_SUCCESS);
}
int main()
{
int shmid = 0;
void* smbuf = get_memptr("read.c", BUF + sizeof(long), &shmid);
long* nbytes_to_save = smbuf + BUF;
key_t key = ftok("read.c", 'b');
int sid = semget(key, 4, IPC_CREAT|0660);
struct sembuf sem_undo_zero[2] = {
{RCV_DIED, 1, 0},
{RCV_DIED, -1, SEM_UNDO}};
semop(sid, &sem_undo_zero[0], 1);
// ERROR("ERROR IN RCV_DIED[0]");
semop(sid, &sem_undo_zero[1], 1);
// ERROR("ERROR IN RCV_DIED[1]");
struct sembuf unlock_mutex_ifdead[2] = {
{SND_MUTEX, 1, SEM_UNDO},
{SND_MUTEX, -1, 0}
};
if(semop(sid, unlock_mutex_ifdead, 2) == -1);
// ERROR("ERROR IN SND_MUTEX");
//char* segm = shmat(shmid, 0, 0);
struct sembuf mutexes[5] = {
{SND_MUTEX, -1, 0},
{RCV_MUTEX, 1, 0},
{SND_DIED, 0, IPC_NOWAIT},
{RCV_MUTEX, 0, 0},
{SND_CONNECT,-1, 0},
};
//memset(shm_ptr, BUF, 0);
//long* nbytes_to_save = 1;
//if(semop(sid, &mutexes[4], 1) == -1);
// ERROR("ERROR TO CONNECT WITH SENDER");
semop(sid, &mutexes[2], 2);
char str[10] = {};
while (*nbytes_to_save != -1)
{
if (write(STDOUT_FILENO, str, *nbytes_to_save) != *nbytes_to_save)
fprintf(stderr, "%ld\n", *nbytes_to_save);
semop(sid, &mutexes[0], 2);
if (semop(sid, &mutexes[2], 2) == -1)
{
printf("Sender dead\n");
exit(1);
}
};
semop(sid, &mutexes[0], 1);
}