int
main( int argc, char **argv )
{
signal( SIGCHLD, SigUserProc );
signal( SIGPIPE, SIG_IGN );
signal_intr( SIGINT, SigInt );
signal_intr( SIGTERM, SigInt );
#if defined(PROXY)
if( argc < 7 )
#elif defined(HTTP_PROXY) || defined(SERVER) || defined(MULTI_PTHREAD)
if( argc < 3 )
#endif
{
#if defined(PROXY)
SERVER_DEBUG( "[PROXY]usage:./server -l 8087 -s 127.0.0.1 -p 12307\n" );
#elif defined(HTTP_PROXY)||defined(SERVER) || defined(MULTI_PTHREAD)
SERVER_DEBUG( "[SERVER]usage:./server -l 8087 \n" );
#endif
return -1;
}
int port = 0;
char *host_ip = NULL;
int host_port = 0;
char c = 0;
while( (c = getopt( argc, argv, "l:s:p:" )) > 0 )
{
switch( c )
{
case ('l'):
port = atoi( optarg );
break;
case ('s'):
host_ip = optarg;
break;
case ('p'):
host_port = atoi( optarg );
break;
default:
#if defined(PROXY)
SERVER_DEBUG( "[PROXY]usage:./server -l 8087 -s 127.0.0.1 -p 12307\n" );
#elif defined(HTTP_PROXY) || defined(SERVER) || defined(MULTI_PTHREAD)
SERVER_DEBUG( "[SERVER]usage:./server -l 8087 \n" );
#endif
return -1;
}
}
#if defined(PROXY)
SERVER_DEBUG( "[PROXY] listen_port:%d host_ip:%s host_port:%d\n", port, host_ip, host_port );
#elif defined(HTTP_PROXY) || defined(SERVER) || defined(MULTI_PTHREAD)
SERVER_DEBUG( "[SERVER] listen_port:%d\n", port );
#endif
(void)server( port, host_ip, host_port );
return 0;
}
void /* Establish the signal handler and set the alarm. */
set_alrm(unsigned int nsec)
{
alrm_flag = 0;
if (signal_intr(SIGALRM, sig_alrm) == SIG_ERR)
log_sys("set_alrm: signal_intr error");
alarm(nsec);
}
void
loop (int ptym, int ignoreeof)
{
pid_t child;
int nread;
char buf[BUFFSIZE];
if ((child = fork ()) < 0)
{
err_sys ("fork error");
}
else if (child == 0)
{ /* child copies stdin to ptym */
for (;;)
{
if ((nread = read (STDIN_FILENO, buf, BUFFSIZE)) < 0)
err_sys ("read error from stdin");
else if (nread == 0)
break; /* EOF on stdin means we're done */
if (writen (ptym, buf, nread) != nread)
err_sys ("writen error to master pty");
}
/*
* We always terminate when we encounter an EOF on stdin,
* but we notify the parent only if ignoreeof is 0.
*/
if (ignoreeof == 0)
kill (getppid (), SIGTERM); /* notify parent */
exit (0); /* and terminate; child can't return */
}
/*
* Parent copies ptym to stdout.
*/
if (signal_intr (SIGTERM, sig_term) == SIG_ERR)
err_sys ("signal_intr error for SIGTERM");
for (;;)
{
if ((nread = read (ptym, buf, BUFFSIZE)) <= 0)
break; /* signal caught, error, or EOF */
if (writen (STDOUT_FILENO, buf, nread) != nread)
err_sys ("writen error to stdout");
}
/*
* There are three ways to get here: sig_term() below caught the
* SIGTERM from the child, we read an EOF on the pty master (which
* means we have to signal the child to stop), or an error.
*/
if (sigcaught == 0) /* tell child if it didn't send us the signal */
kill (child, SIGTERM);
/*
* Parent returns to caller.
*/
}
Sigfunc *
Signal_intr(int signo, Sigfunc *func)
{
Sigfunc *sigfunc;
if ( (sigfunc = signal_intr(signo, func)) == SIG_ERR)
err_sys("signal_intr error");
return(sigfunc);
}
void
loop(int ptym, int ignoreeof)
{
pid_t child;
int nread;
char buf[BUFFSIZE];
if ((child = fork()) < 0) {
err_sys("fork error");
} else if (child == 0) { /* child copies stdin to stdout */
for (;;) {
if ((nread = read(STDIN_FILENO, buf, BUFFSIZE)) < 0)
err_sys("read error from stdin");
else if (nread == 0)
break;
if (writen(ptym, buf, nread) != nread)
err_sys("writen error to master pty");
}
/*
* We always terminate when we encounter an EOF.
* But we notify the parent only if ignoreeof is set.
*/
if (ignoreeof == 0)
kill(getppid(), SIGTERM);
exit(0);
}
/*
* Parent copies ptym to stdout.
*/
if (signal_intr(SIGTERM, sig_term) == SIG_ERR)
err_sys("signal_intr error for SIGTERM");
for (;;) {
if ((nread = read(ptym, buf, BUFFSIZE)) <= 0)
break;
if (writen(STDOUT_FILENO, buf, nread) != nread)
err_sys("writen error to stdout");
}
if (sigcaught == 0)
kill(child, SIGTERM);
/*
* Parent returns to caller.
*/
}
void main()
{
pid_t pid1,pid2,pid3;
int fd;
setbuf(stdout,NULL);
signal_intr(SIGINT,sigint);
if( (fd = open("lockfile",O_RDWR|O_CREAT,0666)) < 0)
err_sys("can't open/create lockfile");
if( (pid1 = fork()) < 0)
err_sys("fork failed");
else if(pid1 == 0){
if(lock_reg(fd,F_SETLK,F_RDLCK,0,SEEK_SET,0)<0)
err_sys("child 1: can't read-lock file");
printf("child 1: obtained read lock on file\n");
pause();
printf("child 1: exit after pause\n");
exit(0);
}
else
sleep(2);
if( (pid2 = fork()) < 0)
err_sys("fork failed");
else if(pid2 == 0){
if(lock_reg(fd,F_SETLK,F_RDLCK,0,SEEK_SET,0)<0)
err_sys("child 2: can't read-lock file");
printf("child 2: obtained read lock on file\n");
pause();
printf("child 2: exit after pause\n");
exit(0);
}
else
sleep(2);
if( (pid3 = fork()) < 0)
err_sys("fork failed");
else if(pid3 == 0){
if(lock_reg(fd,F_SETLK,F_WRLCK,0,SEEK_SET,0)<0)
printf("child 3: can't set write lock: %s\n",strerror(errno));
printf("child 3 about to block in write-lock...\n");
if(lock_reg(fd,F_SETLKW,F_WRLCK,0,SEEK_SET,0) < 0)
err_sys("child 3:can't write-lock file");
printf("child 3 returned and got write lock??\n");
// pause();
printf("child 3: exit after pause\n");
exit(0);
}
else
sleep(2);
if(lock_reg(fd,F_SETLK,F_RDLCK,0,SEEK_SET,0)<0)
printf("parent: can't set read lock: %s\n",strerror(errno));
else
printf("parent:obtained addtional read lock while"
" write lock is pending\n");
printf("killing child 1...\n");
kill(pid1,SIGINT);
printf("killing child 2...\n");
kill(pid2,SIGINT);
printf("killing child 3...\n");
kill(pid3,SIGINT);
exit(0);
}
int main (void)
{
pid_t pid1, pid2, pid3;
int fd;
setbuf (stdout, NULL);
signal_intr (SIGINT, sigint);
/*
* Create a file.
*/
if ((fd = open ("lockfile", O_RDWR | O_CREAT, 0666)) < 0) {
err_sys ("can't open/create lockfile");
}
/*
* Read-lock the file.
*/
if ((pid1 = fork ()) < 0) {
err_sys ("fork failed");
} else if (pid1 == 0) { /* child */
if (lock_reg (fd, F_SETLK, F_RDLCK, 0, SEEK_SET, 0) < 0) {
err_sys ("child 1: can't read-lock file");
}
printf ("child 1: obtained read lock on file\n");
pause ();
printf ("child 1: exit after pause\n");
exit (0);
} else { /* parent */
sleep (2);
}
/*
* Parent continues .. read-lock file again.
*/
if ((pid2 = fork ()) < 0) {
err_sys ("fork failed");
} else if (pid2 == 0) { /* child */
if (lock_reg (fd, F_SETLK, F_RDLCK, 0, SEEK_SET, 0) < 0) {
err_sys ("child 2: can't read-lock file");
}
printf ("child 2: obtained read lock on file\n");
pause ();
printf ("child 2: exit after pause\n");
exit (0);
} else { /* parent */
sleep (2);
}
/*
* Parent continues ... block while trying to write-lock
* the file
*/
if ((pid3 = fork ()) < 0) {
err_sys ("fork failed");
} else if (pid3 == 0) { /* child */
if (lock_reg (fd, F_SETLK, F_WRLCK, 0, SEEK_SET, 0) < 0) {
printf ("child 3: can't set write lock: %s\n",
strerror (errno));
}
printf ("child3 about to block in write-lock...\n");
if (lock_reg (fd, F_SETLKW, F_WRLCK, 0, SEEK_SET, 0) < 0) {
err_sys ("child3: can't write-lock file");
}
printf ("child 3 returned and got write lock???\n");
pause ();
printf ("child 3: exit after pause\n");
exit (0);
} else { /* parent */
sleep (2);
}
/*
* See if a pending write lock will block the next
* read-lock attempt
*/
if (lock_reg (fd, F_SETLK, F_RDLCK, 0, SEEK_SET, 0) < 0) {
printf ("parent: can't set read lock: %s\n",
strerror (errno));
} else {
printf ("parent: obtained additional read lock while"
" write lock is pending\n");
}
printf ("killing child 1...\n");
kill (pid1, SIGINT);
printf ("killing child 2...\n");
kill (pid2, SIGINT);
printf ("killing child 3...\n");
kill (pid3, SIGINT);
exit (0);
}
int main(void){
if(signal_intr(SIGUSR1,sig_usr1) == SIG_ERR)
printf("SIGUSR1 error \n");
kill(getpid(),SIGUSR1);
sleep(5);
}