/* sock.c
 * - General Socket Functions
 *
 * Copyright (c) 1999 Jack Moffitt, Barath Raghavan, and Alexander Haväng
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 */

#ifdef HAVE_CONFIG_H
#ifdef _WIN32
#include <win32config.h>
#else
#include <config.h>
#endif
#endif

#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <sys/types.h>
#include <sys/poll.h>
#include <ctype.h>

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

#include <string.h>
#include <errno.h>
#include <fcntl.h>

#ifndef _WIN32
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/time.h>
#include <netdb.h>
#else
#include <winsock.h>
#endif

#ifndef HAVE_SOCKLEN_T
#define socklen_t int
#endif

#ifndef _WIN32
extern int h_errno, errno;
#endif

#include "sock.h"

int sock_recoverable(int error)
{
	if (error == EAGAIN || error == EINTR || error == EINPROGRESS || error == EWOULDBLOCK) {
		return 1;
	}

	return 0;
}

int sock_valid_socket(SOCKET sockfd)
{
	return (sockfd >= 0);
}

#ifdef _WIN32
int inet_aton(const char *s, struct in_addr *a)
{
	int lsb, b2, b3, msb;

	if (sscanf(s, "%d.%d.%d.%d", &lsb, &b2, &b3, &msb) < 4) {
		return 0;
	}

#ifdef HAVE_INET_ADDR
	a->s_addr = inet_addr(s);
    
	if(a->s_addr == -1)
		return 0;
#else
	a->s_addr = lsb + (b2 << 8) + (b3 << 16) + (msb << 24);
#endif

	return 1;
}
#endif /* _WIN32 */

int sock_set_blocking(SOCKET sockfd, const int block)
{
#ifdef _WIN32
	int varblock = block;
#endif

	if ((!sock_valid_socket(sockfd)) || (block < 0) || (block > 1))
		return SOCKET_ERROR;

#ifdef _WIN32
	return ioctlsocket(sockfd, FIONBIO, &varblock);
#else
	return fcntl(sockfd, F_SETFL, (block == SOCK_BLOCK) ? 0 : O_NONBLOCK);
#endif
}

int sock_close(SOCKET sockfd)
{
#ifdef _WIN32
	return closesocket(sockfd);
#else
	return close(sockfd);
#endif
}

/* 
 *  Write len bytes from buf to the socket.
 */
int sock_write_bytes(SOCKET sockfd, const char *buff, const int len)
{
	int wrote, res, polled;
	struct pollfd socks;

	/* sanity check */
	if (!buff) {
		return SOCKET_ERROR;
	} else if (len <= 0) {
		return SOCKET_ERROR;
	} else if (!sock_valid_socket(sockfd)) {
		return SOCKET_ERROR;
	}

	socks.fd = sockfd;
	socks.events = POLLOUT;

	wrote = 0;
	while (wrote < len) {
		polled = poll(&socks, 1, 30000);

		if ((polled == -1) && sock_recoverable(errno))
			continue;
		if (polled != 1)
			return SOCKET_ERROR;
	
		res = send(sockfd, &buff[wrote], len - wrote, 0);

		if ((res < 0) && (!sock_recoverable(errno)))
			return SOCKET_ERROR;
		if (res > 0)
			wrote += res;
	}
	
	return wrote;
}

/*
 *  Write a string to a socket. 
 */
int sock_write_string(SOCKET sockfd, const char *buff)
{
	return (sock_write_bytes(sockfd, buff, strlen(buff)) > 0);
}

/* 
 * Write a printf() style formatted message to the socket 
 * Return 1 if all bytes where successfully written, and 0 if not.
 * Potential problems: Will truncate the string if longer than 1024 bytes.
 *                     Might fuck everything up if no vsnprintf is available 
 */
int sock_write(SOCKET sockfd, const char *fmt, ...)
{
	char buff[1024];
	va_list ap;

	va_start(ap, fmt);
#ifdef HAVE_VSNPRINTF
	vsnprintf(buff, 1024, fmt, ap);
#else
	vsprintf(buff, fmt, ap);
#endif
	va_end(ap);
	
	return (sock_write_bytes(sockfd, buff, strlen(buff)) > 0);
}

/*
 * Read one line of at max len bytes from sockfd into buff.
 * If ok, return 1 and nullterminate buff. Otherwize return 0.
 * Terminating \n is not put into the buffer.
 * Assert Class: 2
 */
int sock_read_line(SOCKET sockfd, char *buff, const int len)
{
	char c = '\0';
	int read_bytes, pos;
  
	if (!sock_valid_socket(sockfd)) {
		return 0;
	} else if (!buff) {
		return 0;
	} else if (len <= 0) {
		return 0;
	}

	pos = 0;
	read_bytes = recv(sockfd, &c, 1, 0);

	if (read_bytes < 0) {
		return 0;
	}

	while ((c != '\n') && (pos < len) && (read_bytes == 1)) {
		if (c != '\r')
			buff[pos++] = c;
		read_bytes = recv(sockfd, &c, 1, 0);
	}
	
	if (read_bytes == 1) {
		buff[pos] = '\0';
		return 1;
	} else {
		return 0;
	}
}

/*
 * Connect to hostname on specified port and return the created socket.
 */
SOCKET sock_connect_wto(const char *hostname, const int port, const int timeout)
{
	SOCKET sockfd;
	struct sockaddr_in sin, server;

	if (!hostname || !hostname[0]) {
		return INVALID_SOCKET;
	} else if (port <= 0) {
		return INVALID_SOCKET;
	}
		
	sockfd = socket(AF_INET, SOCK_STREAM, 0);
	if (sockfd == INVALID_SOCKET) { 
		sock_close(sockfd); 
		return INVALID_SOCKET; 
	}

	memset(&sin, 0, sizeof(sin));
	memset(&server, 0, sizeof(struct sockaddr_in));

	if (inet_aton(hostname, (struct in_addr *)&sin.sin_addr) == 0) {
		sock_close(sockfd);
		return INVALID_SOCKET;
	}

	memcpy(&server.sin_addr, &sin.sin_addr, sizeof(sin));

	server.sin_family = AF_INET;
	server.sin_port = htons(port);

	/* if we have a timeout, use select, if not, use connect straight. */
	/* dunno if this is portable, and it sure is complicated for such a 
	   simple thing to want to do.  damn BSD sockets! */
	if (timeout > 0) {
		fd_set wfds;
		struct timeval tv;
		int retval;
		int val;
		socklen_t valsize = sizeof(int);

		FD_ZERO(&wfds);
		FD_SET(sockfd, &wfds);
		tv.tv_sec = timeout;
		tv.tv_usec = 0;

		sock_set_blocking(sockfd, SOCK_NONBLOCK);
		retval = connect(sockfd, (struct sockaddr *)&server, sizeof(server));
		if (retval == 0) {
			sock_set_blocking(sockfd, SOCK_BLOCK);
			return sockfd;
		} else {
#ifdef _WIN32
			if (WSAGetLastError() == WSAEINPROGRESS) {
#else
			if (!sock_recoverable(errno)) {
#endif
				sock_close(sockfd);
				return SOCKET_ERROR;
			}
		}

		if (select(sockfd + 1, NULL, &wfds, NULL, &tv)) {
			retval = getsockopt (sockfd, SOL_SOCKET, SO_ERROR, (void *)&val, (socklen_t *)&valsize);
			if ((retval == 0) && (val == 0)) {
				sock_set_blocking(sockfd, SOCK_BLOCK);
				return sockfd;
			} else {
				sock_close(sockfd);
				return SOCKET_ERROR;
			}
		} else {
			sock_close(sockfd);
			return SOCKET_ERROR;
		}
       } else {
	  	if (connect(sockfd, (struct sockaddr *)&server, sizeof(server)) == 0) {
			return sockfd;
		} else {
			sock_close(sockfd);
			return SOCKET_ERROR;
		}
       }
}