/*************************************************************************
* (C) 2010 AITNET ltd - Sofia/Bulgaria - <misho@aitbg.com>
*  by Michael Pounov <misho@openbsd-bg.org>
*
* $Author: misho $
* $Id: cli.c,v 1.9.2.15 2012/05/17 22:57:42 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, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012
	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"


/*
 * rpc_cli_openBLOBClient() - Connect to BLOB Server
 *
 * @rpccli = RPC Client session
 * @Port = Port for bind server, if Port == 0 default port is selected
 * return: NULL == error or !=NULL connection to BLOB server established
 */
rpc_cli_t *
rpc_cli_openBLOBClient(rpc_cli_t * __restrict rpccli, u_short Port)
{
	rpc_cli_t *cli = NULL;

	if (!rpccli) {
		rpc_SetErr(EINVAL, "Invalid parameters can`t connect to BLOB server");
		return NULL;
	}

	cli = malloc(sizeof(rpc_cli_t));
	if (!cli) {
		LOGERR;
		return NULL;
	} else
		memcpy(cli, rpccli, sizeof(rpc_cli_t));

	memcpy(&cli->cli_sa, &rpccli->cli_sa, sizeof(io_sockaddr_t));
	switch (cli->cli_sa.sa.sa_family) {
		case AF_INET:
			cli->cli_sa.sin.sin_port = 
				htons(Port ? Port : ntohs(cli->cli_sa.sin.sin_port) + 1);
			break;
		case AF_INET6:
			cli->cli_sa.sin6.sin6_port = 
				htons(Port ? Port : ntohs(cli->cli_sa.sin6.sin6_port) + 1);
			break;
		case AF_LOCAL:
			strlcat(cli->cli_sa.sun.sun_path, ".blob", sizeof cli->cli_sa.sun.sun_path);
			break;
		default:
			rpc_SetErr(EINVAL, "Invalid socket type %d", cli->cli_sa.sa.sa_family);
			return NULL;
	}

	AIT_COPY_VAL(&cli->cli_buf, &rpccli->cli_buf);

	/* connect to BLOB server */
	cli->cli_sock = socket(cli->cli_sa.sa.sa_family, SOCK_STREAM, 0);
	if (cli->cli_sock == -1) {
		LOGERR;
		free(cli);
		return NULL;
	}
	if (connect(cli->cli_sock, &cli->cli_sa.sa, cli->cli_sa.sa.sa_len) == -1) {
		LOGERR;
		close(cli->cli_sock);
		free(cli);
		return NULL;
	} else
		fcntl(cli->cli_sock, F_SETFL, fcntl(cli->cli_sock, F_GETFL) | O_NONBLOCK);

	return cli;
}

/*
 * rpc_cli_closeBLOBClient() - Close connection to BLOB server and free resources
 *
 * @cli = BLOB Client session
 * return: none
 */
void
rpc_cli_closeBLOBClient(rpc_cli_t ** __restrict cli)
{
	if (!cli || !*cli)
		return;

	shutdown((*cli)->cli_sock, SHUT_RDWR);
	close((*cli)->cli_sock);

	AIT_FREE_VAL(&(*cli)->cli_buf);

	free(*cli);
	*cli = NULL;
}

/* -------------------------------------------------------------- */

/*
 * rpc_cli_openClient() - Connect to RPC Server
 *
 * @ProgID = ProgramID for RPC session request
 * @ProcID = ProcessID for RPC session request
 * @netBuf = Network buffer length (min:512 bytes), if =0 == BUFSIZ (also meaning max RPC packet)
 * @csHost = Host name or IP address for bind server
 * @Port = Port for bind server, if Port == 0 default port is selected
 * return: NULL == error or !=NULL connection to RPC server established
 */
rpc_cli_t *
rpc_cli_openClient(u_int ProgID, u_char ProcID, int netBuf, const char *csHost, u_short Port)
{
	rpc_cli_t *cli = NULL;
	io_sockaddr_t sa;

	if (!io_gethostbyname(csHost, Port, &sa))
		return NULL;
	if (!Port)
		Port = RPC_DEFPORT;
	if (netBuf < RPC_MIN_BUFSIZ)
		netBuf = BUFSIZ;
	else
		netBuf = io_align(netBuf, 1);	/* align netBuf length */

#ifdef HAVE_SRANDOMDEV
	srandomdev();
#else
	time_t tim;

	srandom((time(&tim) ^ getpid()));
#endif

	cli = malloc(sizeof(rpc_cli_t));
	if (!cli) {
		LOGERR;
		return NULL;
	} else
		memset(cli, 0, sizeof(rpc_cli_t));

	/* build session */
	cli->cli_parent = malloc(sizeof(rpc_sess_t));
	if (!cli->cli_parent) {
		LOGERR;
		free(cli);
		return NULL;
	} else {
		((rpc_sess_t*) cli->cli_parent)->sess_version = RPC_VERSION;
		((rpc_sess_t*) cli->cli_parent)->sess_program = ProgID;
		((rpc_sess_t*) cli->cli_parent)->sess_process = ProcID;
	}

	memcpy(&cli->cli_sa, &sa, sizeof cli->cli_sa);
	AIT_SET_BUF2(&cli->cli_buf, 0, netBuf);

	/* connect to RPC server */
	cli->cli_sock = socket(cli->cli_sa.sa.sa_family, SOCK_STREAM, 0);
	if (cli->cli_sock == -1) {
		LOGERR;
		AIT_FREE_VAL(&cli->cli_buf);
		free(cli->cli_parent);
		free(cli);
		return NULL;
	}
	if (connect(cli->cli_sock, &cli->cli_sa.sa, cli->cli_sa.sa.sa_len) == -1) {
		LOGERR;
		AIT_FREE_VAL(&cli->cli_buf);
		close(cli->cli_sock);
		free(cli->cli_parent);
		free(cli);
		return NULL;
	} else
		fcntl(cli->cli_sock, F_SETFL, fcntl(cli->cli_sock, F_GETFL) | O_NONBLOCK);

	return cli;
}

/*
 * rpc_cli_closeClient() - Close connection to RPC server and free resources
 *
 * @cli = RPC Client session
 * return: none
 */
void
rpc_cli_closeClient(rpc_cli_t ** __restrict cli)
{
	if (!cli || !*cli)
		return;

	shutdown((*cli)->cli_sock, SHUT_RDWR);
	close((*cli)->cli_sock);

	AIT_FREE_VAL(&(*cli)->cli_buf);

	if ((*cli)->cli_parent)
		free((*cli)->cli_parent);

	free(*cli);
	*cli = NULL;
}


/*
 * rpc_cli_execCall() - Execute RPC call
 *
 * @cli = RPC Client session
 * @noreply = We not want RPC reply
 * @tag = Function tag for execution
 * @in_vars = IN RPC call array of rpc values, may be NULL
 * @out_vars = OUT returned array of rpc values, if !=NULL must be free after use with io_freeVars()
 * return: -1 error or != -1 ok result
 */
int
rpc_cli_execCall(rpc_cli_t *cli, int noreply, u_short tag, 
		array_t * __restrict in_vars, array_t ** __restrict out_vars)
{
	struct tagRPCCall *rpc;
	int ret = 0, wlen = sizeof(struct tagRPCCall);
	uint16_t crc;
	u_char *buf;
	struct pollfd pfd;

	if (!cli) {
		rpc_SetErr(EINVAL, "Can`t execute call because parameter is null or invalid!");
		return -1;
	} else
		buf = AIT_GET_BUF(&cli->cli_buf);
	if (out_vars)
		*out_vars = NULL;

	/* prepare RPC call */
	rpc = (struct tagRPCCall*) buf;
	rpc_addPktSession(&rpc->call_session, cli->cli_parent);
	rpc->call_argc = htons(io_arraySize(in_vars));
	rpc->call_tag = htons(tag);
	rpc->call_seq = htons(random() % USHRT_MAX);

	/* set reply */
	rpc->call_req.flags = noreply ? RPC_NOREPLY : RPC_REPLY;

	if (io_arraySize(in_vars)) {
		/* marshaling variables */
		ret = io_vars2buffer(buf + wlen, AIT_LEN(&cli->cli_buf) - wlen, in_vars);
		if (ret == -1) {
			rpc_SetErr(EBADRPC, "Failed to prepare RPC packet values");
			return -1;
		} else
			wlen += ret;
	}

	/* total packet length */
	rpc->call_len = htons(wlen);

	/* calculate CRC */
	rpc->call_crc ^= rpc->call_crc;
	rpc->call_crc = htons(crcFletcher16((u_short*) buf, wlen / 2));

	pfd.fd = cli->cli_sock;
	pfd.events = POLLOUT;
	do {
		if ((ret = poll(&pfd, 1, DEF_RPC_TIMEOUT * 1000)) < 1 || 
				pfd.revents & (POLLERR | POLLHUP | POLLNVAL)) {
			if (ret) {
				if (errno == EAGAIN)
					continue;
				else
					LOGERR;
			} else
				rpc_SetErr(ETIMEDOUT, "Timeout, can't send to RPC server");
			return -1;
		}
	} while (0);
	if ((ret = send(cli->cli_sock, buf, wlen, MSG_NOSIGNAL)) == -1) {
		LOGERR;
		return -1;
	} else if (ret != wlen) {
		rpc_SetErr(EPROCUNAVAIL, "RPC request, should be send %d bytes, "
				"really sended %d bytes", wlen, ret);
		return -1;
	}

	if (noreply)	/* we not want reply */
		return 0;

	/* reply from RPC server */
	pfd.events = POLLIN | POLLPRI;
	do {
		if ((ret = poll(&pfd, 1, DEF_RPC_TIMEOUT * 1000)) < 1 || 
				pfd.revents & (POLLERR | POLLHUP | POLLNVAL)) {
			if (ret) {
				if (errno == EAGAIN)
					continue;
				else
					LOGERR;
			} else
				rpc_SetErr(ETIMEDOUT, "Timeout, no answer from RPC server");
			return -1;
		}
	} while (0);
	memset(buf, 0, AIT_LEN(&cli->cli_buf));
	if ((ret = recv(cli->cli_sock, buf, AIT_LEN(&cli->cli_buf), 0)) < 1) {
		if (ret)
			LOGERR;
		return -1;
	}
	if (ret < sizeof(struct tagRPCCall)) {
		rpc_SetErr(ERPCMISMATCH, "Short RPC packet");
		return -1;
	}

	/* calculate CRC */
	crc = ntohs(rpc->call_crc);
	rpc->call_crc ^= rpc->call_crc;
	if (crc != crcFletcher16((u_short*) buf, ret / 2)) {
		rpc_SetErr(ERPCMISMATCH, "Bad CRC RPC packet");
		return -1;
	}

	/* check RPC packet session info */
	if (rpc_chkPktSession(&rpc->call_session, cli->cli_parent)) {
		rpc_SetErr(ERPCMISMATCH, "Get invalid RPC session");
		return -1;
	} else
		wlen = sizeof(struct tagRPCCall);
	if (ntohs(rpc->call_tag) != tag) {
		rpc_SetErr(ERPCMISMATCH, "Get wrong RPC reply");
		return -1;
	}
	if (ntohl(rpc->call_rep.eno) && ntohl(rpc->call_rep.ret) == -1) {
		rpc_SetErr(ntohl(rpc->call_rep.eno), "Server side: retcode=%d #%d %s", 
				ntohl(rpc->call_rep.ret), ntohl(rpc->call_rep.eno), 
				strerror(ntohl(rpc->call_rep.eno)));
		return -1;
	}
	if (ntohs(rpc->call_argc) * sizeof(ait_val_t) > AIT_LEN(&cli->cli_buf) - wlen) {
		rpc_SetErr(EMSGSIZE, "Reply RPC packet is too long ...");
		return -1;
	}

	/* RPC is OK! Go de-marshaling variables ... */
	if (out_vars && ntohs(rpc->call_argc)) {
		*out_vars = io_buffer2vars(buf + wlen, AIT_LEN(&cli->cli_buf) - wlen, 
				ntohs(rpc->call_argc), 0);
		if (!*out_vars) {
			rpc_SetErr(io_GetErrno(), "%s", io_GetError());
			return -1;
		}
	}

	ret = ntohl(rpc->call_rep.ret);
	return ret;
}

/*
 * rpc_cli_ping() - Ping RPC server
 *
 * @cli = connected client
 * return: -1 error or !=-1 ping seq id
 */
inline int
rpc_cli_ping(rpc_cli_t *cli)
{
	int ret = 0;
	array_t *arr = NULL;

	if (!cli)
		return -1;

	if (rpc_cli_execCall(cli, RPC_REPLY, CALL_SRVPING, NULL, &arr))
		return -1;
	else
		ret = AIT_GET_U16(io_getVars(arr, 0));
	io_freeVars(&arr);

	return ret;
}