/*
 * Copyright © 2005,2008 Red Hat, Inc. All rights reserved.
 *
 * This copyrighted material is made available to anyone wishing to use,
 * modify, copy, or redistribute it subject to the terms and conditions of the
 * GNU General Public License v.2.  This program is distributed in the hope
 * that it will be useful, but WITHOUT ANY WARRANTY expressed or implied,
 * including the implied warranties of MERCHANTABILITY or FITNESS FOR A
 * PARTICULAR PURPOSE. See the GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc., 51
 * Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. Any Red Hat
 * trademarks that are incorporated in the source code or documentation are not
 * subject to the GNU General Public License and may only be used or replicated
 * with the express permission of Red Hat, Inc.
 *
 * Red Hat Author(s): Nathan Straz <nstraz@redhat.com>
 *                    Dean Jansa <djansa@redhat.com>
 */
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/uio.h>
#include <netinet/in.h>
#include <stdio.h>
#include <string.h>
#include <netdb.h>
#include <errno.h>
#include <syslog.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>

#include "qarsh_packet.h"

static int packet_seq = 1;
/* Some generic socket related functions to make things easier */

int
getsockport(int sd)
{
	struct sockaddr_storage addr;
	socklen_t addrlen;

	addrlen = sizeof addr;
	if (getsockname(sd, (struct sockaddr *)&addr, &addrlen) == 0) {
		if (addr.ss_family == AF_INET) {
			struct sockaddr_in *ipv4p = (struct sockaddr_in *)&addr;
			return ntohs(ipv4p->sin_port);
		} else {
			struct sockaddr_in6 *ipv6p = (struct sockaddr_in6 *)&addr;
			return ntohs(ipv6p->sin6_port);
		}
	} else {
		return -1;
	}
}

int
bind_any(int minport, unsigned short ss_family)
{
	static int lastminport = 0;
	static int nextport = 0;
	int sd;
	struct sockaddr_storage addr;

	if (minport == lastminport) {
		minport = nextport;
	} else {
		lastminport = minport;
	}
	
	sd = socket(ss_family, SOCK_STREAM, 0);
	if (sd == -1) return -1;

	if (ss_family == AF_INET) {
		struct sockaddr_in *ipv4p = (struct sockaddr_in *)&addr;
		ipv4p->sin_family = AF_INET;
		ipv4p->sin_addr.s_addr = htonl(INADDR_ANY);
		do {
			ipv4p->sin_port = htons(minport++);
		} while (bind(sd, (struct sockaddr *)&addr, sizeof addr) != 0);
	} else {
		struct sockaddr_in6 *ipv6p = (struct sockaddr_in6 *)&addr;
		ipv6p->sin6_family = AF_INET6;
		ipv6p->sin6_addr = in6addr_any;
		do {
			ipv6p->sin6_port = htons(minport++);
		} while (bind(sd, (struct sockaddr *)&addr, sizeof addr) != 0);
	}
	nextport = minport;

	if (listen(sd, 0) == -1) {
		syslog(LOG_WARNING, "listen error %d, %s", errno,
				strerror(errno));
	}
	return sd;
}

int
connect_to_host(char *hostname, int port, unsigned short *ss_family)
{
	struct addrinfo *ail;
	struct addrinfo *aip;
	struct addrinfo hints;
	char portstr[NI_MAXSERV];
	int sd;
	int err;

	memset(&hints, 0, sizeof hints);
	hints.ai_family = AF_UNSPEC;
	hints.ai_socktype = SOCK_STREAM;

	memset(portstr, 0, sizeof portstr);
	snprintf(portstr, NI_MAXSERV, "%d", port);

	if ((err = getaddrinfo(hostname, portstr, &hints, &ail)) != 0) {
		fprintf(stderr, "Could not resolve hostname %s: %s\n", 
		        hostname, gai_strerror(err));
		return -1;
	}

	/* TBD -- do we loop over all of the addrinfos returned trying to 
  	 * connect, or just pick the first one? */ 

	for (aip = ail; aip != NULL; aip = aip->ai_next) {
#if 0
		char hname[NI_MAXHOST] = "";
		char nname[NI_MAXHOST] = "";
		
		err = getnameinfo(aip->ai_addr, aip->ai_addrlen, hname, NI_MAXHOST, NULL, 0, 0); 
		err = getnameinfo(aip->ai_addr, aip->ai_addrlen, nname, NI_MAXHOST, NULL, 0, NI_NUMERICHOST); 
 
		if (err != 0) {
			printf("error in getnameinfo: %s\n", gai_strerror(err));
			continue;
		}
 
		if (*hname && *nname) {
			printf("Trying: %s (%s) -- ", hname, nname);
			if (aip->ai_family == AF_INET6) puts("IPv6");
			if (aip->ai_family == AF_INET) puts("IPv4");
		}
#endif

		sd = socket(aip->ai_family, aip->ai_socktype, aip->ai_protocol);
		if (sd == -1) return -1;
		if (connect(sd, aip->ai_addr, aip->ai_addrlen) == -1) {
			close(sd);
			continue;
		} else {
			*ss_family=aip->ai_family;
			freeaddrinfo(ail);
			return sd;
		}
	}

	freeaddrinfo(ail);
	return -1;
}

int
connect_to_peer(struct sockaddr_storage *peer, int port)
{
	int sd;
	int fdflags;
	struct sockaddr_in ipv4;
	struct sockaddr_in6 ipv6;
	struct sockaddr_storage *peeraddr;

	if (peer->ss_family == AF_INET) {
		ipv4.sin_family = AF_INET;
		ipv4.sin_port=htons(port);
		ipv4.sin_addr = ((struct sockaddr_in *)peer)->sin_addr;
		peeraddr = (struct sockaddr_storage *)&ipv4;
	} else {
		ipv6.sin6_family = AF_INET6;
		ipv6.sin6_port=htons(port);
		ipv6.sin6_addr = ((struct sockaddr_in6 *)peer)->sin6_addr;
		peeraddr = (struct sockaddr_storage *)&ipv6;
	}
       
	sd = socket(peer->ss_family, SOCK_STREAM, 0);
	if (sd == -1) return -1;

	/* Set close-on-exec for these sds */
	if ((fdflags = fcntl(sd, F_GETFD, 0)) < 0) {
		return -1;
	}

	fdflags |= FD_CLOEXEC;
	if (fcntl(sd, F_SETFD, fdflags) < 0) {
		return -1;
	}

	if (connect(sd, (struct sockaddr *)peeraddr, sizeof *peeraddr) == -1) {
		return -1;
	}
	return sd;
}

/* 
 * All incoming and outgoing packets go through this function.
 * Caller should make sure the fd is ready to read.
 */
struct qa_packet *
recv_packet(int fd)
{
	char buf[QARSH_MAX_PACKET_SIZE];
	uint32_t packetsize;
	int bufused = 0;
	int ret = 0;

	if ((ret = read(fd, &packetsize, sizeof packetsize)) < 0) {
		if (errno != ECONNRESET) {
		       	fprintf(stderr, "Read error while reading packet size: %s\n", strerror(errno));
		}
		return NULL;
	} else if (ret == 0) {
		return NULL;
	} else if (ret != sizeof packetsize) {
		fprintf(stderr, "Did not read packet size");
		return NULL;
	}
	packetsize = ntohl(packetsize);
	if (packetsize > QARSH_MAX_PACKET_SIZE) {
		fprintf(stderr, "Packet size too large, %d > %d\n", packetsize, QARSH_MAX_PACKET_SIZE);
		return NULL;
	}
	/* Keep reading until we get the whole packet and nothing but the packet, so help me socket */
	do {
		if ((ret = read(fd, buf+bufused, packetsize-bufused)) < 0) {
			fprintf(stderr, "Read error while reading packet data: %s\n", strerror(errno));
			return NULL;
		}
		bufused += ret;
	} while (bufused < packetsize);

	return parse_packet(buf, packetsize);
}

int
send_packet(int fd, struct qa_packet *qp)
{
	char buf[QARSH_MAX_PACKET_SIZE];
	uint32_t netsize;
	int len;
	ssize_t ret = -1;
	struct iovec iovs[2];

	qp->qp_seq = packet_seq++;

	len = qptostr(qp, buf, QARSH_MAX_PACKET_SIZE - sizeof netsize);

	if (len > 0) {
		netsize = htonl(len);
		iovs[0].iov_base = &netsize;
		iovs[0].iov_len = sizeof netsize;
		iovs[1].iov_base = buf;
		iovs[1].iov_len = len;

		ret = writev(fd, iovs, 2);
	}
	return ret;
}