/*************************************************************************
* (C) 2013 AITNET ltd - Sofia/Bulgaria - <misho@aitnet.org>
*  by Michael Pounov <misho@elwix.org>
*
* $Author: misho $
* $Id: sock.c,v 1.16 2016/08/18 09:06:31 misho Exp $
*
**************************************************************************
The ELWIX and AITNET software is distributed under the following
terms:

All of the documentation and software included in the ELWIX and AITNET
Releases is copyrighted by ELWIX - Sofia/Bulgaria <info@elwix.org>

Copyright 2004 - 2016
	by Michael Pounov <misho@elwix.org>.  All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
   notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
   notice, this list of conditions and the following disclaimer in the
   documentation and/or other materials provided with the distribution.
3. All advertising materials mentioning features or use of this software
   must display the following acknowledgement:
This product includes software developed by Michael Pounov <misho@elwix.org>
ELWIX - Embedded LightWeight unIX and its contributors.
4. Neither the name of AITNET nor the names of its contributors
   may be used to endorse or promote products derived from this software
   without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY AITNET AND CONTRIBUTORS ``AS IS'' AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.
*/
#include "global.h"


static void *
io_closeClient(sched_task_t *task)
{
	sock_cli_t *cli = (sock_cli_t*) TASK_ARG(task);
	sock_t *s = (sock_t*) cli->cli_parent;
	int stat;

	schedCancelby(s->sock_root, taskMAX, CRITERIA_ARG, cli, NULL);

	pthread_mutex_lock(&s->sock_mtx);
	TAILQ_REMOVE(&s->sock_cli, cli, cli_node);
	pthread_mutex_unlock(&s->sock_mtx);

	if (*cli->cli_name)
		ioFreePTY(cli->cli_pty, cli->cli_name);
	if (s->sock_prog) {
		io_progDetach(s->sock_prog, cli->cli_pty);
#if 0
		io_progCloseAt(s->sock_prog, cli->cli_pty);
#endif
		cli->cli_pty ^= cli->cli_pty;
		io_progCheck(s->sock_prog, 42);
	}

	if (s->sock_type == SOCK_STREAM) {
		shutdown(cli->cli_fd, SHUT_RDWR);
		close(cli->cli_fd);
	}
	AIT_FREE_VAL(&cli->cli_buf[1]);
	AIT_FREE_VAL(&cli->cli_buf[0]);

	if (cli->cli_pid > 0) {
		kill(cli->cli_pid, SIGKILL);
		while (waitpid(cli->cli_pid, &stat, WNOHANG) > 0) {
			usleep(1000);
			kill(cli->cli_pid, SIGKILL);
		}
	}

	e_free(cli);
	taskExit(task, NULL);
}

static void *
io_acceptClient(sched_task_t *task)
{
	int c, rlen;
	sockaddr_t sa;
	socklen_t salen = sizeof sa.ss;
	sock_cli_t *cli = NULL;
	sock_t *s = (sock_t*) TASK_ARG(task);

	if (s->sock_type == SOCK_STREAM) {
		if ((c = accept(TASK_FD(task), &sa.sa, &salen)) == -1) {
			LOGERR;
			goto end;
		}
	} else {
		if ((rlen = recvfrom(TASK_FD(task), 
						AIT_GET_BUF(&s->sock_buf), AIT_LEN(&s->sock_buf), 
						MSG_PEEK, &sa.sa, &salen)) == -1) {
			LOGERR;
			goto end;
		} else
			c = TASK_FD(task);
	}

	cli = e_malloc(sizeof(sock_cli_t));
	if (!cli) {
		io_SetErr(elwix_GetErrno(), "%s", elwix_GetError());
		if (s->sock_type == SOCK_STREAM)
			close(c);
		goto end;
	} else {
		memset(cli, 0, sizeof(sock_cli_t));
		pthread_mutex_lock(&s->sock_mtx);
		TAILQ_INSERT_TAIL(&s->sock_cli, cli, cli_node);
		pthread_mutex_unlock(&s->sock_mtx);
	}

	cli->cli_parent = TASK_ARG(task);
	cli->cli_fd = c;
	cli->cli_func = TASK_DATA(task);
	memcpy(&cli->cli_addr, &sa, sizeof cli->cli_addr);
	AIT_SET_BUFSIZ(&cli->cli_buf[0], 0, AIT_LEN(&s->sock_buf));
	AIT_SET_BUFSIZ(&cli->cli_buf[1], 0, AIT_LEN(&s->sock_buf));

	schedRead(TASK_ROOT(task), cli->cli_func, cli, cli->cli_fd, TASK_ARG(task), 0);
	ioUpdTimerSocket(cli);
end:
	schedReadSelf(task);
	taskExit(task, NULL);
}

static void *
io_txNet(sched_task_t *task)
{
	int wlen, ret, len = TASK_DATLEN(task);
	sock_cli_t *cli = TASK_ARG(task);
	sock_t *s = (sock_t*) cli->cli_parent;
	u_char *buf = TASK_DATA(task);
	struct pollfd pfd[1];

	pfd->fd = TASK_FD(task);
	pfd->events = POLLOUT;
	pfd->revents = 0;
	for(; len > 0; len -= wlen, buf += wlen) {
		ioUpdTimerSocket(cli);

		if ((ret = poll(pfd, 1, s->sock_timeout.tv_sec * 1000)) < 1 || 
				pfd->revents & (POLLNVAL | POLLERR | POLLHUP)) {
#if 0
			if (!ret)
				continue;
#endif
			schedEvent(TASK_ROOT(task), io_closeClient, cli, 0, NULL, 0);
			break;
		}

		if (s->sock_type == SOCK_STREAM)
			wlen = send(TASK_FD(task), buf, len, 0);
		else
#ifndef __linux__
			wlen = sendto(TASK_FD(task), buf, len, 0, &cli->cli_addr.sa, cli->cli_addr.sa.sa_len);
#else
			wlen = sendto(TASK_FD(task), buf, len, 0, &cli->cli_addr.sa, 
					cli->cli_addr.sa.sa_family == AF_INET ? 
					sizeof cli->cli_addr.sin : sizeof cli->cli_addr.sin6);
#endif
		if (wlen < 1) {
			schedEvent(TASK_ROOT(task), io_closeClient, cli, 0, NULL, 0);
			break;
		}
	}

	taskExit(task, NULL);
}

static void *
io_txPty(sched_task_t *task)
{
	int wlen;
	sock_cli_t *cli = TASK_ARG(task);

	ioUpdTimerSocket(cli);

	wlen = write(TASK_FD(task), TASK_DATA(task), TASK_DATLEN(task));
	if (wlen < 1)
		schedEvent(TASK_ROOT(task), io_closeClient, cli, 0, NULL, 0);

	taskExit(task, NULL);
}

static void *
io_rxNet(sched_task_t *task)
{
	int rlen;
	sock_cli_t *cli = TASK_ARG(task);
	sock_t *s = (sock_t*) cli->cli_parent;
	sockaddr_t sa;
	socklen_t salen = sizeof sa.ss;

	ioUpdTimerSocket(cli);

	if (s->sock_type == SOCK_STREAM)
		rlen = recv(TASK_FD(task), AIT_GET_BUF(&cli->cli_buf[0]), 
				AIT_LEN(&cli->cli_buf[0]), 0);
	else {
		rlen = recvfrom(TASK_FD(task), AIT_GET_BUF(&cli->cli_buf[0]), 
				AIT_LEN(&cli->cli_buf[0]), 0, &sa.sa, &salen);
		if (e_addrcmp(&cli->cli_addr, &sa, 42)) {
			schedReadSelf(task);
			taskExit(task, NULL);
		}
	}
	if (rlen < 1)
		schedEvent(TASK_ROOT(task), io_closeClient, cli, 0, NULL, 0);
	else {
		schedEvent(TASK_ROOT(task), io_txPty, cli, cli->cli_pty, 
				AIT_GET_BUF(&cli->cli_buf[0]), rlen);
		schedReadSelf(task);
	}

	taskExit(task, NULL);
}

static void *
io_rxPty(sched_task_t *task)
{
	int rlen;
	sock_cli_t *cli = TASK_ARG(task);

	ioUpdTimerSocket(cli);

	rlen = read(TASK_FD(task), AIT_GET_BUF(&cli->cli_buf[1]), AIT_LEN(&cli->cli_buf[1]));
	if (rlen < 1)
		schedEvent(TASK_ROOT(task), io_closeClient, cli, 0, NULL, 0);
	else {
		schedEvent(TASK_ROOT(task), io_txNet, cli, cli->cli_fd, 
				AIT_GET_BUF(&cli->cli_buf[1]), rlen);
		schedReadSelf(task);
	}

	taskExit(task, NULL);
}

static void *
io_bridgeClient(sched_task_t *task)
{
	int c, rlen, pty;
	pid_t pid;
	sockaddr_t sa;
	socklen_t salen = sizeof sa.ss;
	sock_cli_t *cli = NULL;
	sock_t *s = (sock_t*) TASK_ARG(task);
	array_t *args = NULL;
	char **argv = NULL;

	if (s->sock_type == SOCK_STREAM) {
		if ((c = accept(TASK_FD(task), &sa.sa, &salen)) == -1) {
			LOGERR;
			goto end;
		}
	} else {
		if ((rlen = recvfrom(TASK_FD(task), 
						AIT_GET_BUF(&s->sock_buf), AIT_LEN(&s->sock_buf), 
						MSG_PEEK, &sa.sa, &salen)) == -1) {
			LOGERR;
			goto end;
		} else
			c = TASK_FD(task);
	}

	cli = e_malloc(sizeof(sock_cli_t));
	if (!cli) {
		io_SetErr(elwix_GetErrno(), "%s", elwix_GetError());
		if (s->sock_type == SOCK_STREAM)
			close(c);
		goto end;
	} else {
		memset(cli, 0, sizeof(sock_cli_t));
		pthread_mutex_lock(&s->sock_mtx);
		TAILQ_INSERT_TAIL(&s->sock_cli, cli, cli_node);
		pthread_mutex_unlock(&s->sock_mtx);
	}

	cli->cli_parent = TASK_ARG(task);
	cli->cli_fd = c;
	strlcpy(cli->cli_cmdline, TASK_DATA(task), sizeof cli->cli_cmdline);
	memcpy(&cli->cli_addr, &sa, sizeof cli->cli_addr);
	AIT_SET_BUFSIZ(&cli->cli_buf[0], 0, AIT_LEN(&s->sock_buf));
	AIT_SET_BUFSIZ(&cli->cli_buf[1], 0, AIT_LEN(&s->sock_buf));

	switch ((pid = ioForkPTY(&pty, cli->cli_name, sizeof cli->cli_name, 
				NULL, NULL, NULL))) {
		case -1:
			ELIBERR(io);
			break;
		case 0:
			cli->cli_pty = pty;
			ioSetRAWMode(STDIN_FILENO, NULL);

			array_Args(cli->cli_cmdline, 0, " \t", &args);
			argv = array_To(args);
			array_Destroy(&args);

#if 0
			printf("Console %s\n", cli->cli_name);
#endif
			rlen = execv(*argv, argv);
			_exit(rlen);
			break;
		default:
			cli->cli_pty = pty;
			cli->cli_pid = pid;

			schedRead(TASK_ROOT(task), io_rxPty, cli, cli->cli_pty, 
					TASK_ARG(task), 0);
			schedRead(TASK_ROOT(task), io_rxNet, cli, cli->cli_fd, 
					TASK_ARG(task), 0);
			ioUpdTimerSocket(cli);
			break;
	}
end:
	schedReadSelf(task);
	taskExit(task, NULL);
}

static void *
io_bridgeClient2Pool(sched_task_t *task)
{
	int c, rlen;
	sockaddr_t sa;
	socklen_t salen = sizeof sa.ss;
	sock_cli_t *cli = NULL;
	sock_t *s = (sock_t*) TASK_ARG(task);

	if (s->sock_type == SOCK_STREAM) {
		if ((c = accept(TASK_FD(task), &sa.sa, &salen)) == -1) {
			LOGERR;
			goto end;
		}
	} else {
		if ((rlen = recvfrom(TASK_FD(task), 
						AIT_GET_BUF(&s->sock_buf), AIT_LEN(&s->sock_buf), 
						MSG_PEEK, &sa.sa, &salen)) == -1) {
			LOGERR;
			goto end;
		} else
			c = TASK_FD(task);
	}

	cli = e_malloc(sizeof(sock_cli_t));
	if (!cli) {
		io_SetErr(elwix_GetErrno(), "%s", elwix_GetError());
		if (s->sock_type == SOCK_STREAM)
			close(c);
		goto end;
	} else {
		memset(cli, 0, sizeof(sock_cli_t));
		pthread_mutex_lock(&s->sock_mtx);
		TAILQ_INSERT_TAIL(&s->sock_cli, cli, cli_node);
		pthread_mutex_unlock(&s->sock_mtx);
	}

	io_progCheck(s->sock_prog, 42);

	cli->cli_parent = TASK_ARG(task);
	cli->cli_fd = c;
	cli->cli_pty = io_progAttach(s->sock_prog, 42);
	strlcpy(cli->cli_cmdline, TASK_DATA(task), sizeof cli->cli_cmdline);
	memcpy(&cli->cli_addr, &sa, sizeof cli->cli_addr);
	AIT_SET_BUFSIZ(&cli->cli_buf[0], 0, AIT_LEN(&s->sock_buf));
	AIT_SET_BUFSIZ(&cli->cli_buf[1], 0, AIT_LEN(&s->sock_buf));

	schedRead(TASK_ROOT(task), io_rxPty, cli, cli->cli_pty, TASK_ARG(task), 0);
	schedRead(TASK_ROOT(task), io_rxNet, cli, cli->cli_fd, TASK_ARG(task), 0);
	ioUpdTimerSocket(cli);
end:
	schedReadSelf(task);
	taskExit(task, NULL);
}


/*
 * ioInitSocket() - Init socket and allocate resources
 *
 * @role = Socket role
 * @type = Socket type
 * @proto = Socket protocol
 * @addr = Bind to address
 * @port = Bind to port
 * @buflen = Socket buffer, optional if =0 == BUFSIZ
 * return: NULL error or !=NULL created socket
 */
sock_t *
ioInitSocket(int role, int type, int proto, const char *addr, u_short port, size_t buflen)
{
	sock_t *s = NULL;
	int n = 1;

	if (!addr)
		return NULL;

	s = e_malloc(sizeof(sock_t));
	if (!s) {
		io_SetErr(elwix_GetErrno(), "%s", elwix_GetError());
		return NULL;
	} else
		memset(s, 0, sizeof(sock_t));

	TAILQ_INIT(&s->sock_cli);

	s->sock_role = role;
	s->sock_type = type;
	s->sock_proto = proto;
	if (!e_gethostbyname(addr, port, &s->sock_addr)) {
		io_SetErr(elwix_GetErrno(), "%s", elwix_GetError());
		e_free(s);
		return NULL;
	} else {
		buflen = buflen ? buflen : BUFSIZ;
		buflen = E_ALIGN(buflen, 2);	/* align buflen length */
		AIT_SET_BUFSIZ(&s->sock_buf, 0, buflen);
	}

	s->sock_fd = socket(s->sock_addr.sa.sa_family, s->sock_type, s->sock_proto);
	if (s->sock_fd == -1) {
		LOGERR;
		AIT_FREE_VAL(&s->sock_buf);
		e_free(s);
		return NULL;
	}
	if (setsockopt(s->sock_fd, SOL_SOCKET, SO_SNDBUF, &buflen, sizeof buflen) == -1) {
		LOGERR;
		AIT_FREE_VAL(&s->sock_buf);
		e_free(s);
		return NULL;
	}
	if (setsockopt(s->sock_fd, SOL_SOCKET, SO_RCVBUF, &buflen, sizeof buflen) == -1) {
		LOGERR;
		AIT_FREE_VAL(&s->sock_buf);
		e_free(s);
		return NULL;
	}
	if (setsockopt(s->sock_fd, SOL_SOCKET, SO_REUSEADDR, &n, sizeof n) == -1) {
		LOGERR;
		AIT_FREE_VAL(&s->sock_buf);
		e_free(s);
		return NULL;
	}
#ifndef __linux__
	if (bind(s->sock_fd, &s->sock_addr.sa, s->sock_addr.sa.sa_len) == -1) {
#else
	if (bind(s->sock_fd, &s->sock_addr.sa, s->sock_addr.sa.sa_family == AF_INET ? 
				sizeof s->sock_addr.sin : sizeof s->sock_addr.sin6) == -1) {
#endif
		LOGERR;
		AIT_FREE_VAL(&s->sock_buf);
		e_free(s);
		return NULL;
	}

	s->sock_root = schedBegin();
	if (!s->sock_root) {
		io_SetErr(sched_GetErrno(), "%s", sched_GetError());
		AIT_FREE_VAL(&s->sock_buf);
		e_free(s);
		return NULL;
	}

	pthread_mutex_init(&s->sock_mtx, NULL);
	return s;
}

/*
 * ioCloseSocket() - Close socket and free resources
 *
 * @s = Socket
 * return: none
 */
void
ioCloseSocket(sock_t ** __restrict s)
{
	sock_cli_t *cli;
	int stat;

	if (s && *s) {
		pthread_mutex_lock(&(*s)->sock_mtx);
		while ((cli = TAILQ_FIRST(&(*s)->sock_cli))) {
			TAILQ_REMOVE(&(*s)->sock_cli, cli, cli_node);

			schedCancelby((*s)->sock_root, taskMAX, CRITERIA_ARG, cli, NULL);

			if ((*s)->sock_type == SOCK_STREAM) {
				shutdown(cli->cli_fd, SHUT_RDWR);
				close(cli->cli_fd);
			}
			AIT_FREE_VAL(&cli->cli_buf[1]);
			AIT_FREE_VAL(&cli->cli_buf[0]);

			if (cli->cli_pid > 0) {
				kill(cli->cli_pid, SIGKILL);
				while (waitpid(cli->cli_pid, &stat, WNOHANG) > 0) {
					usleep(1000);
					kill(cli->cli_pid, SIGKILL);
				}
			}

			e_free(cli);
		}
		pthread_mutex_unlock(&(*s)->sock_mtx);

		shutdown((*s)->sock_fd, SHUT_RDWR);
		close((*s)->sock_fd);

		AIT_FREE_VAL(&(*s)->sock_buf);

		schedEnd(&(*s)->sock_root);

		pthread_mutex_destroy(&(*s)->sock_mtx);
		e_free(*s);
		*s = NULL;
	}
}

/*
 * ioUpSocket() - Setup socket for use
 *
 * @s = Socket
 * @arg = Server role = listen backlog queue and Client role = peer address
 * @timeout = Socket timeout in sec (default -1 infinit)
 * return: -1 error or 0 ok
 */
int
ioUpSocket(sock_t * __restrict s, void *arg, int timeout)
{
	int ret = 0;
	sockaddr_t *peer = (sockaddr_t*) arg;
	uintptr_t backlog = (uintptr_t) arg;

	if (!s || !arg)
		return -1;
	else {
		s->sock_timeout.tv_sec = timeout;
		s->sock_timeout.tv_nsec = (timeout < 1) ? timeout : 0;
		schedPolling(s->sock_root, &s->sock_timeout, NULL);
	}

	switch (s->sock_role) {
		case IO_SOCK_ROLE_CLIENT:
			memcpy(&s->sock_peer, peer, sizeof s->sock_peer);

#ifndef __linux__
			if (connect(s->sock_fd, &s->sock_peer.sa, s->sock_peer.sa.sa_len) == -1) {
#else
			if (connect(s->sock_fd, &s->sock_peer.sa, s->sock_addr.sa.sa_family == AF_INET ? 
						sizeof s->sock_peer.sin : sizeof s->sock_peer.sin6) == -1) {
#endif
				LOGERR;
				return -1;
			}
			break;
		case IO_SOCK_ROLE_SERVER:
			if (s->sock_type == SOCK_STREAM) {
				s->sock_backq = backlog;

				if (listen(s->sock_fd, s->sock_backq) == -1) {
					LOGERR;
					return -1;
				}
			}
			break;
		default:
			io_SetErr(EINVAL, "Unsupported socket type");
			return -1;
	}

	fcntl(s->sock_fd, F_SETFL, fcntl(s->sock_fd, F_GETFL) | O_NONBLOCK);
	return ret;
}

/*
 * ioUpdTimerSocket() - Update timeout of socket
 *
 * @c = Client socket
 * return:  none
 */
void
ioUpdTimerSocket(sock_cli_t * __restrict c)
{
	sock_t *s;

	if (!c)
		return;
	else
		s = c->cli_parent;

	if (s->sock_prog)
		io_progCheck(s->sock_prog, 42);

	schedCancelby(s->sock_root, taskTIMER, CRITERIA_ARG, c, NULL);
	schedTimer(s->sock_root, io_closeClient, c, s->sock_timeout, NULL, 0);
}

/*
 * ioCloseClient() - Close client socket
 *
 * @c = Client socket
 * return: 0 ok or !=0 error
 */
int
ioCloseClient(sock_cli_t * __restrict c)
{
	sock_t *s;

	if (!c)
		return -1;
	else
		s = c->cli_parent;

	return !schedEvent(s->sock_root, io_closeClient, c, 0, NULL, 0);
}

/*
 * ioLoopSocket() - Start socket scheduler
 *
 * @s = Socket
 * @rcb = Read callback
 * return: -1 error or return result from scheduler
 */
int
ioLoopSocket(sock_t * __restrict s, sched_task_func_t rcb)
{
	if (!s || !rcb || s->sock_kill)
		return -1;

	schedRead(s->sock_root, io_acceptClient, s, s->sock_fd, rcb, 0);
	return schedRun(s->sock_root, &s->sock_kill);
}

static void *
io_progPurge(sched_task_t *task)
{
	sock_t *s = (sock_t*) TASK_ARG(task);

	io_progVacuum(s->sock_prog, 0);

	schedTimer(TASK_ROOT(task), TASK_FUNC(task), TASK_ARG(task), 
			s->sock_timeout, TASK_DATA(task), TASK_DATLEN(task));
	taskExit(task, NULL);
}

/*
 * ioBridgeProg2Socket() - Start socket scheduler and bridge program to socket
 *
 * @s = Socket
 * @prgname = Program name
 * return: 0 ok or !=0 error
 */
int
ioBridgeProg2Socket(sock_t * __restrict s, const char *prgname)
{
	if (!s || !prgname || s->sock_kill)
		return -1;

	if (s->sock_prog) {
		schedRead(s->sock_root, io_bridgeClient2Pool, 
				s, s->sock_fd, (void*) prgname, 0);
		schedTimer(s->sock_root, io_progPurge, s, s->sock_timeout, NULL, 0);
	} else
		schedRead(s->sock_root, io_bridgeClient, 
				s, s->sock_fd, (void*) prgname, 0);
	return schedRun(s->sock_root, &s->sock_kill);
}

/*
 * ioSetupProg2Socket() - Setup program pool to socket server
 *
 * @s = Socket
 * @p = Program pool
 * return: -1 error or 0 ok
 */
int
ioSetupProg2Socket(sock_t * __restrict s, prog_t * __restrict p)
{
	if (!s)
		return -1;

	s->sock_prog = p;
	return 0;
}