/*
 * Copyright (c) 1987-2017 by the citadel.org team
 *
 * This program is open source software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, version 3.
 * 
 * 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.
 */

/*
 * Uncomment this to log all communications with the Citadel server
#define SERV_TRACE 1
 */

#include "webcit.h"
#include "webserver.h"

long MaxRead = -1; /* should we do READ scattered or all at once? */

/*
 * register the timeout
 */
RETSIGTYPE timeout(int signum)
{
	syslog(LOG_WARNING, "Connection timed out; unable to reach citserver\n");
	/* no exit here, since we need to server the connection unreachable thing. exit(3); */
}


/*
 * Client side - connect to a unix domain socket
 */
int uds_connectsock(char *sockpath)
{
	struct sockaddr_un addr;
	int s;

	memset(&addr, 0, sizeof(addr));
	addr.sun_family = AF_UNIX;
	strncpy(addr.sun_path, sockpath, sizeof addr.sun_path);

	s = socket(AF_UNIX, SOCK_STREAM, 0);
	if (s < 0) {
		syslog(LOG_WARNING, "Can't create socket [%s]: %s\n", sockpath, strerror(errno));
		return(-1);
	}

	if (connect(s, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
		syslog(LOG_WARNING, "Can't connect [%s]: %s\n", sockpath, strerror(errno));
		close(s);
		return(-1);
	}
	return s;
}


/*
 * TCP client - connect to a host/port 
 */
int tcp_connectsock(char *host, char *service)
{
	struct in6_addr serveraddr;
	struct addrinfo hints;
	struct addrinfo *res = NULL;
	struct addrinfo *ai = NULL;
	int rc = (-1);
	int s = (-1);

	if ((host == NULL) || IsEmptyStr(host))
		return (-1);
	if ((service == NULL) || IsEmptyStr(service))
		return (-1);

	syslog(LOG_DEBUG, "tcp_connectsock(%s,%s)\n", host, service);

	memset(&hints, 0x00, sizeof(hints));
	hints.ai_flags = AI_NUMERICSERV;
	hints.ai_family = AF_UNSPEC;
	hints.ai_socktype = SOCK_STREAM;

	/*
	 * Handle numeric IPv4 and IPv6 addresses
	 */
	rc = inet_pton(AF_INET, host, &serveraddr);
	if (rc == 1) {						/* dotted quad */
		hints.ai_family = AF_INET;
		hints.ai_flags |= AI_NUMERICHOST;
	} else {
		rc = inet_pton(AF_INET6, host, &serveraddr);
		if (rc == 1) {					/* IPv6 address */
			hints.ai_family = AF_INET6;
			hints.ai_flags |= AI_NUMERICHOST;
		}
	}

	/* Begin the connection process */

	rc = getaddrinfo(host, service, &hints, &res);
	if (rc != 0) {
		syslog(LOG_DEBUG, "%s: %s\n", host, gai_strerror(rc));
		freeaddrinfo(res);
		return(-1);
	}

	/*
	 * Try all available addresses until we connect to one or until we run out.
	 */
	for (ai = res; ai != NULL; ai = ai->ai_next) {

		if (ai->ai_family == AF_INET) syslog(LOG_DEBUG, "Trying IPv4\n");
		else if (ai->ai_family == AF_INET6) syslog(LOG_DEBUG, "Trying IPv6\n");
		else syslog(LOG_WARNING, "This is going to fail.\n");

		s = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
		if (s < 0) {
			syslog(LOG_WARNING, "socket() failed: %s\n", strerror(errno));
			freeaddrinfo(res);
			return(-1);
		}
		rc = connect(s, ai->ai_addr, ai->ai_addrlen);
		if (rc >= 0) {
			int fdflags;
			freeaddrinfo(res);

			fdflags = fcntl(rc, F_GETFL);
			if (fdflags < 0) {
				syslog(LOG_ERR,
				       "unable to get socket %d flags! %s \n",
				       rc,
				       strerror(errno));
				close(rc);
				return -1;
			}
			fdflags = fdflags | O_NONBLOCK;
			if (fcntl(rc, F_SETFL, fdflags) < 0) {
				syslog(LOG_ERR,
				       "unable to set socket %d nonblocking flags! %s \n",
				       rc,
				       strerror(errno));
				close(s);
				return -1;
			}

			return(s);
		}
		else {
			syslog(LOG_WARNING, "connect() failed: %s\n", strerror(errno));
			close(s);
		}
	}
        freeaddrinfo(res);
	return(-1);
}


/*
 *  input string from pipe
 */
int serv_getln(char *strbuf, int bufsize)
{
	wcsession *WCC = WC;
	int len;

	*strbuf = '\0';
	StrBuf_ServGetln(WCC->MigrateReadLineBuf);
	len = StrLength(WCC->MigrateReadLineBuf);
	if (len > bufsize)
		len = bufsize - 1;
	memcpy(strbuf, ChrPtr(WCC->MigrateReadLineBuf), len);
	FlushStrBuf(WCC->MigrateReadLineBuf);
	strbuf[len] = '\0';
#ifdef SERV_TRACE
	syslog(LOG_DEBUG, "%3d<<<%s\n", WCC->serv_sock, strbuf);
#endif
	return len;
}


int StrBuf_ServGetln(StrBuf *buf)
{
	wcsession *WCC = WC;
	const char *ErrStr = NULL;
	int rc;
	
	if (!WCC->connected)
		return -1;

	FlushStrBuf(buf);
	rc = StrBufTCP_read_buffered_line_fast(buf, 
					       WCC->ReadBuf, 
					       &WCC->ReadPos, 
					       &WCC->serv_sock, 
					       5, 1, 
					       &ErrStr);
	if (rc < 0)
	{
		syslog(LOG_INFO, "StrBuf_ServGetln(): Server connection broken: %s\n",
			(ErrStr)?ErrStr:"");
		wc_backtrace(LOG_INFO);
		if (WCC->serv_sock > 0) close(WCC->serv_sock);
		WCC->serv_sock = (-1);
		WCC->connected = 0;
		WCC->logged_in = 0;
	}
#ifdef SERV_TRACE
	else 
	{
		long pos = 0;
		if (WCC->ReadPos != NULL)
			pos = WCC->ReadPos - ChrPtr(WCC->ReadBuf);
		syslog(LOG_DEBUG, "%3d<<<[%ld]%s\n", WC->serv_sock, pos, ChrPtr(buf));
	}
#endif
	return rc;
}

int StrBuf_ServGetBLOBBuffered(StrBuf *buf, long BlobSize)
{
	wcsession *WCC = WC;
	const char *ErrStr;
	int rc;
	
	rc = StrBufReadBLOBBuffered(buf, 
				    WCC->ReadBuf, 
				    &WCC->ReadPos,
				    &WCC->serv_sock, 
				    1, 
				    BlobSize, 
				    NNN_TERM,
				    &ErrStr);
	if (rc < 0)
	{
		syslog(LOG_INFO, "StrBuf_ServGetBLOBBuffered(): Server connection broken: %s\n",
			(ErrStr)?ErrStr:"");
		wc_backtrace(LOG_INFO);
		if (WCC->serv_sock > 0) close(WCC->serv_sock);
		WCC->serv_sock = (-1);
		WCC->connected = 0;
		WCC->logged_in = 0;
	}
#ifdef SERV_TRACE
        else
                syslog(LOG_DEBUG, "%3d<<<BLOB: %d bytes\n", WC->serv_sock, StrLength(buf));
#endif

	return rc;
}

int StrBuf_ServGetBLOB(StrBuf *buf, long BlobSize)
{
	wcsession *WCC = WC;
	const char *ErrStr;
	int rc;
	
	WCC->ReadPos = NULL;
	rc = StrBufReadBLOB(buf, &WCC->serv_sock, 1, BlobSize, &ErrStr);
	if (rc < 0)
	{
		syslog(LOG_INFO, "StrBuf_ServGetBLOB(): Server connection broken: %s\n",
			(ErrStr)?ErrStr:"");
		wc_backtrace(LOG_INFO);
		if (WCC->serv_sock > 0) close(WCC->serv_sock);
		WCC->serv_sock = (-1);
		WCC->connected = 0;
		WCC->logged_in = 0;
	}
#ifdef SERV_TRACE
        else
                syslog(LOG_DEBUG, "%3d<<<BLOB: %d bytes\n", WC->serv_sock, StrLength(buf));
#endif

	return rc;
}


void FlushReadBuf (void)
{
	long len;
	const char *pch;
	const char *pche;
	wcsession *WCC = WC;

	len = StrLength(WCC->ReadBuf);
	if ((len > 0) &&
	    (WCC->ReadPos != NULL) && 
	    (WCC->ReadPos != StrBufNOTNULL))
		
	{
		pch = ChrPtr(WCC->ReadBuf);
		pche = pch + len;
		if (WCC->ReadPos != pche)
		{
			syslog(LOG_ERR,
				"ERROR: somebody didn't eat his soup! Remaing Chars: %ld [%s]\n", 
				(long)(pche - WCC->ReadPos),
				pche
			);
			syslog(LOG_ERR, 
				"--------------------------------------------------------------------------------\n"
				"Whole buf: [%s]\n"
				"--------------------------------------------------------------------------------\n", 
				pch);
			AppendImportantMessage(HKEY("Suppenkasper alert! watch your webcit logfile and get connected to your favourite opensource Crew."));
		}
	}

	FlushStrBuf(WCC->ReadBuf);
	WCC->ReadPos = NULL;


}


/*
 *  send binary to server
 *  buf the buffer to write to citadel server
 *  nbytes how many bytes to send to citadel server
 */
int serv_write(const char *buf, int nbytes)
{
	wcsession *WCC = WC;
	int bytes_written = 0;
	int retval;

	FlushReadBuf();
	while (bytes_written < nbytes) {
		retval = write(WCC->serv_sock, &buf[bytes_written],
			       nbytes - bytes_written);
		if (retval < 1) {
			const char *ErrStr = strerror(errno);
			syslog(LOG_INFO, "serv_write(): Server connection broken: %s\n",
				(ErrStr)?ErrStr:"");
			if (WCC->serv_sock > 0) close(WCC->serv_sock);
			WCC->serv_sock = (-1);
			WCC->connected = 0;
			WCC->logged_in = 0;
			return 0;
		}
		bytes_written = bytes_written + retval;
	}
	return 1;
}


/*
 *  send line to server
 *  string the line to send to the citadel server
 */
int serv_puts(const char *string)
{
#ifdef SERV_TRACE
	syslog(LOG_DEBUG, "%3d>>>%s\n", WC->serv_sock, string);
#endif
	FlushReadBuf();

	if (!serv_write(string, strlen(string)))
		return 0;
	return serv_write("\n", 1);
}

/*
 *  send line to server
 *  string the line to send to the citadel server
 */
int serv_putbuf(const StrBuf *string)
{
#ifdef SERV_TRACE
	syslog(LOG_DEBUG, "%3d>>>%s\n", WC->serv_sock, ChrPtr(string));
#endif
	FlushReadBuf();

	if (!serv_write(ChrPtr(string), StrLength(string)))
		return 0;
	return serv_write("\n", 1);
}


/*
 *  convenience function to send stuff to the server
 *  format the formatstring
 *  ... the entities to insert into format 
 */
int serv_printf(const char *format,...)
{
	va_list arg_ptr;
	char buf[SIZ];
	size_t len;
	int rc;

	FlushReadBuf();

	va_start(arg_ptr, format);
	vsnprintf(buf, sizeof buf, format, arg_ptr);
	va_end(arg_ptr);

	len = strlen(buf);
	buf[len++] = '\n';
	buf[len] = '\0';
	rc = serv_write(buf, len);
#ifdef SERV_TRACE
	syslog(LOG_DEBUG, ">>>%s", buf);
#endif
	return rc;
}


/*
 * Read binary data from server into memory using a series of server READ commands.
 * returns the read content as StrBuf
 */
int serv_read_binary(StrBuf *Ret, size_t total_len, StrBuf *Buf) 
{
	wcsession *WCC = WC;
	size_t bytes_read = 0;
	size_t this_block = 0;
	int rc = 6;
	int ServerRc = 6;

	if (Ret == NULL) {
		return -1;
	}

	while ((bytes_read < total_len) && (ServerRc == 6)) {

		if (WCC->serv_sock==-1) {
			FlushStrBuf(Ret); 
			return -1; 
		}

		serv_printf("READ "SIZE_T_FMT"|"SIZE_T_FMT, bytes_read, total_len-bytes_read);
		if ( (rc = StrBuf_ServGetln(Buf) > 0) &&
		     (ServerRc = GetServerStatus(Buf, NULL), ServerRc == 6) ) 
		{
			if (rc < 0)
				return rc;
			StrBufCutLeft(Buf, 4);
			this_block = StrTol(Buf);
			rc = StrBuf_ServGetBLOBBuffered(Ret, this_block);
			if (rc < 0) {
				syslog(LOG_INFO, "Server connection broken during download\n");
				wc_backtrace(LOG_INFO);
				if (WCC->serv_sock > 0) close(WCC->serv_sock);
				WCC->serv_sock = (-1);
				WCC->connected = 0;
				WCC->logged_in = 0;
				return rc;
			}
			bytes_read += rc;
		}
	}

	return StrLength(Ret);
}


int client_write(StrBuf *ThisBuf)
{
	wcsession *WCC = WC;
        const char *ptr, *eptr;
        long count;
	ssize_t res = 0;
        fd_set wset;
        int fdflags;

	ptr = ChrPtr(ThisBuf);
	count = StrLength(ThisBuf);
	eptr = ptr + count;

	fdflags = fcntl(WC->Hdr->http_sock, F_GETFL);

        while ((ptr < eptr) && (WCC->Hdr->http_sock != -1)) {
                if ((fdflags & O_NONBLOCK) == O_NONBLOCK) {
                        FD_ZERO(&wset);
                        FD_SET(WCC->Hdr->http_sock, &wset);
                        if (select(WCC->Hdr->http_sock + 1, NULL, &wset, NULL, NULL) == -1) {
                                syslog(LOG_INFO, "client_write: Socket select failed (%s)\n", strerror(errno));
                                return -1;
                        }
                }

                if ((WCC->Hdr->http_sock == -1) || 
		    ((res = write(WCC->Hdr->http_sock, ptr, count)),
		     (res == -1)))
		{
                        syslog(LOG_INFO, "client_write: Socket write failed (%s)\n", strerror(errno));
			wc_backtrace(LOG_INFO);
                        return -1;
                }
                count -= res;
		ptr += res;
        }
	return 0;
}


int
read_serv_chunk(

	StrBuf *Buf,
	size_t total_len,
	size_t *bytes_read
	)
{
	int rc;
	int ServerRc;
	wcsession *WCC = WC;

	serv_printf("READ "SIZE_T_FMT"|"SIZE_T_FMT, *bytes_read, total_len-(*bytes_read));
	if ( (rc = StrBuf_ServGetln(Buf) > 0) &&
	     (ServerRc = GetServerStatus(Buf, NULL), ServerRc == 6) ) 
	{
		size_t this_block = 0;

		if (rc < 0)
			return rc;

		StrBufCutLeft(Buf, 4);
		this_block = StrTol(Buf);
		rc = StrBuf_ServGetBLOBBuffered(WCC->WBuf, this_block);
		if (rc < 0) {
			syslog(LOG_INFO, "Server connection broken during download\n");
			wc_backtrace(LOG_INFO);
			if (WCC->serv_sock > 0) close(WCC->serv_sock);
			WCC->serv_sock = (-1);
			WCC->connected = 0;
			WCC->logged_in = 0;
			return rc;
		}
		*bytes_read += rc;
	}
	return 6;
}

static inline int send_http(StrBuf *Buf)
{
#ifdef HAVE_OPENSSL
	if (is_https)
		return client_write_ssl(Buf);
	else
#endif
		return client_write(Buf);
}
/*
 * Read binary data from server into memory using a series of server READ commands.
 * returns the read content as StrBuf
 */
void serv_read_binary_to_http(StrBuf *MimeType, size_t total_len, int is_static, int detect_mime)
{
	int ServerRc = 6;
	wcsession *WCC = WC;
	size_t bytes_read = 0;
	int first = 1;
	int client_con_state = 0;
	int chunked = 0;
	int is_gzip = 0;
	const char *Err = NULL;
	StrBuf *BufHeader = NULL;
	StrBuf *Buf;
	StrBuf *pBuf = NULL;
	vStreamT *SC = NULL;
	IOBuffer ReadBuffer;
	IOBuffer WriteBuffer;
	

	Buf = NewStrBuf();

	if (WCC->Hdr->HaveRange)
	{
		WCC->Hdr->HaveRange++;
		WCC->Hdr->TotalBytes = total_len;
		/* open range? or beyound file border? correct the numbers. */
		if ((WCC->Hdr->RangeTil == -1) || (WCC->Hdr->RangeTil>= total_len))
			WCC->Hdr->RangeTil = total_len - 1;
		bytes_read = WCC->Hdr->RangeStart;
		total_len = WCC->Hdr->RangeTil;
	}
	else
		chunked = total_len > SIZ * 10; /* TODO: disallow for HTTP / 1.0 */

	if (chunked)
	{
		BufHeader = NewStrBuf();
	}

	if ((detect_mime != 0) && (bytes_read != 0))
	{
		/* need to read first chunk to detect mime, though the client doesn't care */
		size_t bytes_read = 0;
		const char *CT;

		ServerRc = read_serv_chunk(
			Buf,
			total_len,
			&bytes_read);

		if (ServerRc != 6)
		{
			FreeStrBuf(&BufHeader);
			FreeStrBuf(&Buf);
			return;
		}
		CT = GuessMimeType(SKEY(WCC->WBuf));
		FlushStrBuf(WCC->WBuf);
		StrBufPlain(MimeType, CT, -1);
		CheckGZipCompressionAllowed(SKEY(MimeType));
		detect_mime = 0;
		FreeStrBuf(&Buf);
	}

	memset(&WriteBuffer, 0, sizeof(IOBuffer));
	if (chunked && !DisableGzip && WCC->Hdr->HR.gzip_ok)
	{
		is_gzip = 1;
		SC = StrBufNewStreamContext (eZLibEncode, &Err);
		if (SC == NULL) {
			syslog(LOG_ERR, "Error while initializing stream context: %s", Err);
			FreeStrBuf(&Buf);
			return;
		}

		memset(&ReadBuffer, 0, sizeof(IOBuffer));
		ReadBuffer.Buf = WCC->WBuf;

		WriteBuffer.Buf = NewStrBufPlain(NULL, SIZ*2);;
		pBuf = WriteBuffer.Buf;
	}
	else
	{
		pBuf = WCC->WBuf;
	}

	if (!detect_mime)
	{
		http_transmit_headers(ChrPtr(MimeType), is_static, chunked, is_gzip);
		
		if (send_http(WCC->HBuf) < 0)
		{
			FreeStrBuf(&Buf);
			FreeStrBuf(&WriteBuffer.Buf);
			FreeStrBuf(&BufHeader);
			if (StrBufDestroyStreamContext(eZLibEncode, &SC, &Err) && Err) {
				syslog(LOG_ERR, "Error while destroying stream context: %s", Err);
			}
			return;
		}
	}

	while ((bytes_read < total_len) &&
	       (ServerRc == 6) &&
	       (client_con_state == 0))
	{

		if (WCC->serv_sock==-1) {
			FlushStrBuf(WCC->WBuf); 
			FreeStrBuf(&Buf);
			FreeStrBuf(&WriteBuffer.Buf);
			FreeStrBuf(&BufHeader);
			StrBufDestroyStreamContext(eZLibEncode, &SC, &Err);
			if (StrBufDestroyStreamContext(eZLibEncode, &SC, &Err) && Err) {
				syslog(LOG_ERR, "Error while destroying stream context: %s", Err);
			}
			return;
		}

		ServerRc = read_serv_chunk(
			Buf,
			total_len,
			&bytes_read);
		if (ServerRc != 6)
			break;

		if (detect_mime)
		{
			const char *CT;
			detect_mime = 0;
			
			CT = GuessMimeType(SKEY(WCC->WBuf));
			StrBufPlain(MimeType, CT, -1);
			if (is_gzip) {
				CheckGZipCompressionAllowed(SKEY(MimeType));
				is_gzip = WCC->Hdr->HR.gzip_ok;
			}
			http_transmit_headers(ChrPtr(MimeType), is_static, chunked, is_gzip);
			
			client_con_state = send_http(WCC->HBuf);
		}

		if (is_gzip)
		{
			int done = (bytes_read == total_len);
			while ((IOBufferStrLength(&ReadBuffer) > 0) && (client_con_state == 0)) {
				int rc;

				do {
					rc = StrBufStreamTranscode(eZLibEncode, &WriteBuffer, &ReadBuffer, NULL, -1, SC, done, &Err);

					if (StrLength (pBuf) > 0) {
						StrBufPrintf(BufHeader, "%s%x\r\n", 
						     (first)?"":"\r\n",
							     StrLength (pBuf));
						first = 0;
						client_con_state = send_http(BufHeader);
						if (client_con_state == 0) {
							client_con_state = send_http(pBuf);
						}
						FlushStrBuf(pBuf);
					}
				} while ((rc == 1) && (StrLength(pBuf) > 0));
			}
			FlushStrBuf(WCC->WBuf);
		}
		else {
			if ((chunked) && (client_con_state == 0))
			{
				StrBufPrintf(BufHeader, "%s%x\r\n", 
					     (first)?"":"\r\n",
					     StrLength (pBuf));
				first = 0;
				client_con_state = send_http(BufHeader);
			}

			if (client_con_state == 0)
				client_con_state = send_http(pBuf);

			FlushStrBuf(pBuf);
		}
	}

	if (SC && StrBufDestroyStreamContext(eZLibEncode, &SC, &Err) && Err) {
		syslog(LOG_ERR, "Error while destroying stream context: %s", Err);
	}
	FreeStrBuf(&WriteBuffer.Buf);
	if ((chunked) && (client_con_state == 0))
	{
		StrBufPlain(BufHeader, HKEY("\r\n0\r\n\r\n"));
		if (send_http(BufHeader) < 0)
		{
			FreeStrBuf(&Buf);
		        FreeStrBuf(&BufHeader);
			return;
		}
	}
	FreeStrBuf(&BufHeader);
	FreeStrBuf(&Buf);
}

int ClientGetLine(ParsedHttpHdrs *Hdr, StrBuf *Target)
{
	const char *Error;
#ifdef HAVE_OPENSSL
	const char *pch, *pchs;
	int rlen, len, retval = 0;

	if (is_https) {
		int ntries = 0;
		if (StrLength(Hdr->ReadBuf) > 0)
		{
			pchs = ChrPtr(Hdr->ReadBuf);
			pch = strchr(pchs, '\n');
			if (pch != NULL) {
				rlen = 0;
				len = pch - pchs;
				if (len > 0 && (*(pch - 1) == '\r') )
					rlen ++;
				StrBufSub(Target, Hdr->ReadBuf, 0, len - rlen);
				StrBufCutLeft(Hdr->ReadBuf, len + 1);
				return len - rlen;
			}
		}

		while (retval == 0) { 
				pch = NULL;
				pchs = ChrPtr(Hdr->ReadBuf);
				if (*pchs != '\0')
					pch = strchr(pchs, '\n');
				if (pch == NULL) {
					retval = client_read_sslbuffer(Hdr->ReadBuf, SLEEPING);
					pchs = ChrPtr(Hdr->ReadBuf);
					pch = strchr(pchs, '\n');
					if (pch == NULL)
						retval = 0;
				}
				if (retval == 0) {
					sleeeeeeeeeep(1);
					ntries ++;
				}
				if (ntries > 10)
					return 0;
		}
		if ((retval > 0) && (pch != NULL)) {
			rlen = 0;
			len = pch - pchs;
			if (len > 0 && (*(pch - 1) == '\r') )
				rlen ++;
			StrBufSub(Target, Hdr->ReadBuf, 0, len - rlen);
			StrBufCutLeft(Hdr->ReadBuf, len + 1);
			return len - rlen;

		}
		else 
			return -1;
	}
	else 
#endif
		return StrBufTCP_read_buffered_line_fast(Target, 
							 Hdr->ReadBuf,
							 &Hdr->Pos,
							 &Hdr->http_sock,
							 5,
							 1,
							 &Error);
}


/* 
 * This is a generic function to set up a master socket for listening on
 * a TCP port.  The server shuts down if the bind fails.  (IPv4/IPv6 version)
 *
 * ip_addr 	IP address to bind
 * port_number	port number to bind
 * queue_len	number of incoming connections to allow in the queue
 */
int webcit_tcp_server(const char *ip_addr, int port_number, int queue_len)
{
	const char *ipv4broadcast = "0.0.0.0";
	int IsDefault = 0;
	struct protoent *p;
	struct sockaddr_in6 sin6;
	struct sockaddr_in sin4;
	int s, i, b;
	int ip_version = 6;

retry:
	memset(&sin6, 0, sizeof(sin6));
	memset(&sin4, 0, sizeof(sin4));
	sin6.sin6_family = AF_INET6;
	sin4.sin_family = AF_INET;

	if (	(ip_addr == NULL)							/* any IPv6 */
		|| (IsEmptyStr(ip_addr))
		|| (!strcmp(ip_addr, "*"))
	) {
		IsDefault = 1;
		ip_version = 6;
		sin6.sin6_addr = in6addr_any;
	}
	else if (!strcmp(ip_addr, "0.0.0.0"))						/* any IPv4 */
	{
		ip_version = 4;
		sin4.sin_addr.s_addr = INADDR_ANY;
	}
	else if ((strchr(ip_addr, '.')) && (!strchr(ip_addr, ':')))			/* specific IPv4 */
	{
		ip_version = 4;
		if (inet_pton(AF_INET, ip_addr, &sin4.sin_addr) <= 0) {
			syslog(LOG_WARNING, "Error binding to [%s] : %s\n", ip_addr, strerror(errno));
			return (-WC_EXIT_BIND);
		}
	}
	else										/* specific IPv6 */
	{
		ip_version = 6;
		if (inet_pton(AF_INET6, ip_addr, &sin6.sin6_addr) <= 0) {
			syslog(LOG_WARNING, "Error binding to [%s] : %s\n", ip_addr, strerror(errno));
			return (-WC_EXIT_BIND);
		}
	}

	if (port_number == 0) {
		syslog(LOG_WARNING, "Cannot start: no port number specified.\n");
		return (-WC_EXIT_BIND);
	}
	sin6.sin6_port = htons((u_short) port_number);
	sin4.sin_port = htons((u_short) port_number);

	p = getprotobyname("tcp");

	s = socket( ((ip_version == 6) ? PF_INET6 : PF_INET), SOCK_STREAM, (p->p_proto));
	if (s < 0) {
		if (IsDefault && (errno == EAFNOSUPPORT))
		{
			s = 0;
			ip_addr = ipv4broadcast;
			goto retry;
		}
		syslog(LOG_WARNING, "Can't create a listening socket: %s\n", strerror(errno));
		return (-WC_EXIT_BIND);
	}
	/* Set some socket options that make sense. */
	i = 1;
	setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &i, sizeof(i));

	if (ip_version == 6) {
		b = bind(s, (struct sockaddr *) &sin6, sizeof(sin6));
	}
	else {
		b = bind(s, (struct sockaddr *) &sin4, sizeof(sin4));
	}

	if (b < 0) {
		syslog(LOG_ERR, "Can't bind: %s\n", strerror(errno));
		close(s);
		return (-WC_EXIT_BIND);
	}

	if (listen(s, queue_len) < 0) {
		syslog(LOG_ERR, "Can't listen: %s\n", strerror(errno));
		close(s);
		return (-WC_EXIT_BIND);
	}
	return (s);
}


/*
 * Create a Unix domain socket and listen on it
 * sockpath - file name of the unix domain socket
 * queue_len - Number of incoming connections to allow in the queue
 */
int webcit_uds_server(char *sockpath, int queue_len)
{
	struct sockaddr_un addr;
	int s;
	int i;
	int actual_queue_len;

	actual_queue_len = queue_len;
	if (actual_queue_len < 5) actual_queue_len = 5;

	i = unlink(sockpath);
	if ((i != 0) && (errno != ENOENT)) {
		syslog(LOG_WARNING, "webcit: can't unlink %s: %s\n",
			sockpath, strerror(errno));
		return (-WC_EXIT_BIND);
	}

	memset(&addr, 0, sizeof(addr));
	addr.sun_family = AF_UNIX;
	safestrncpy(addr.sun_path, sockpath, sizeof addr.sun_path);

	s = socket(AF_UNIX, SOCK_STREAM, 0);
	if (s < 0) {
		syslog(LOG_WARNING, "webcit: Can't create a unix domain socket: %s\n", strerror(errno));
		return (-WC_EXIT_BIND);
	}

	if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
		syslog(LOG_WARNING, "webcit: Can't bind: %s\n", strerror(errno));
		close(s);
		return (-WC_EXIT_BIND);
	}

	if (listen(s, actual_queue_len) < 0) {
		syslog(LOG_WARNING, "webcit: Can't listen: %s\n", strerror(errno));
		close(s);
		return (-WC_EXIT_BIND);
	}

	chmod(sockpath, 0777);
	return(s);
}




/*
 * Read data from the client socket.
 *
 * sock		socket fd to read from
 * buf		buffer to read into 
 * bytes	number of bytes to read
 * timeout	Number of seconds to wait before timing out
 *
 * Possible return values:
 *      1       Requested number of bytes has been read.
 *      0       Request timed out.
 *	-1   	Connection is broken, or other error.
 */
int client_read_to(ParsedHttpHdrs *Hdr, StrBuf *Target, int bytes, int timeout)
{
	const char *Error;
	int retval = 0;

#ifdef HAVE_OPENSSL
	if (is_https) {
		long bufremain = 0;
		long baselen;

		baselen = StrLength(Target);

		if (Hdr->Pos == NULL)
			Hdr->Pos = ChrPtr(Hdr->ReadBuf);

		if (StrLength(Hdr->ReadBuf) > 0)
		{
			bufremain = StrLength(Hdr->ReadBuf) - (Hdr->Pos - ChrPtr(Hdr->ReadBuf));
			
			if (bytes < bufremain)
				bufremain = bytes;
			StrBufAppendBufPlain(Target, Hdr->Pos, bufremain, 0);
			StrBufCutLeft(Hdr->ReadBuf, bufremain);
		}

		if (bytes > bufremain) 
		{
			while ((StrLength(Hdr->ReadBuf) + StrLength(Target) < bytes + baselen) &&
			       (retval >= 0))
				retval = client_read_sslbuffer(Hdr->ReadBuf, timeout);
			if (retval >= 0) {
				StrBufAppendBuf(Target, Hdr->ReadBuf, 0); /* todo: Buf > bytes? */
				return 1;
			}
			else {
				syslog(LOG_INFO, "client_read_ssl() failed\n");
				return -1;
			}
		}
		else 
			return 1;
	}
#endif

	retval = StrBufReadBLOBBuffered(Target, 
					Hdr->ReadBuf, 
					&Hdr->Pos, 
					&Hdr->http_sock, 
					1, 
					bytes,
					O_TERM,
					&Error);
	if (retval < 0) {
		syslog(LOG_INFO, "client_read() failed: %s\n",
			Error);
		wc_backtrace(LOG_DEBUG);
		return retval;
	}

	return 1;
}


/*
 * Begin buffering HTTP output so we can transmit it all in one write operation later.
 */
void begin_burst(void)
{
	if (WC->WBuf == NULL) {
		WC->WBuf = NewStrBufPlain(NULL, 32768);
	}
}


/*
 * Finish buffering HTTP output.  [Compress using zlib and] output with a Content-Length: header.
 */
long end_burst(void)
{
	wcsession *WCC = WC;
        const char *ptr, *eptr;
        long count;
	ssize_t res = 0;
        fd_set wset;
        int fdflags;

	if (!DisableGzip && (WCC->Hdr->HR.gzip_ok))
	{
		if (CompressBuffer(WCC->WBuf) > 0)
			hprintf("Content-encoding: gzip\r\n");
		else {
			syslog(LOG_ALERT, "Compression failed: %d [%s] sending uncompressed\n", errno, strerror(errno));
			wc_backtrace(LOG_INFO);
		}
	}

	if (WCC->WFBuf != NULL) {
		WildFireSerializePayload(WCC->WFBuf, WCC->HBuf, &WCC->Hdr->nWildfireHeaders, NULL);
		FreeStrBuf(&WCC->WFBuf);
	}

	if (WCC->Hdr->HR.prohibit_caching)
		hprintf("Pragma: no-cache\r\nCache-Control: no-store\r\nExpires:-1\r\n");
	hprintf("Content-length: %d\r\n\r\n", StrLength(WCC->WBuf));

	ptr = ChrPtr(WCC->HBuf);
	count = StrLength(WCC->HBuf);
	eptr = ptr + count;

#ifdef HAVE_OPENSSL
	if (is_https) {
		client_write_ssl(WCC->HBuf);
		client_write_ssl(WCC->WBuf);
		return (count);
	}
#endif

	if (WCC->Hdr->http_sock == -1)
		return -1;
	fdflags = fcntl(WC->Hdr->http_sock, F_GETFL);

	while ((ptr < eptr) && (WCC->Hdr->http_sock != -1)){
                if ((fdflags & O_NONBLOCK) == O_NONBLOCK) {
                        FD_ZERO(&wset);
                        FD_SET(WCC->Hdr->http_sock, &wset);
                        if (select(WCC->Hdr->http_sock + 1, NULL, &wset, NULL, NULL) == -1) {
                                syslog(LOG_DEBUG, "client_write: Socket select failed (%s)\n", strerror(errno));
                                return -1;
                        }
                }

                if ((WCC->Hdr->http_sock == -1) || 
		    (res = write(WCC->Hdr->http_sock, 
				 ptr,
				 count)) == -1) {
                        syslog(LOG_DEBUG, "client_write: Socket write failed (%s)\n", strerror(errno));
		        wc_backtrace(LOG_INFO);
                        return res;
                }
                count -= res;
		ptr += res;
        }

	ptr = ChrPtr(WCC->WBuf);
	count = StrLength(WCC->WBuf);
	eptr = ptr + count;

        while ((ptr < eptr) && (WCC->Hdr->http_sock != -1)) {
                if ((fdflags & O_NONBLOCK) == O_NONBLOCK) {
                        FD_ZERO(&wset);
                        FD_SET(WCC->Hdr->http_sock, &wset);
                        if (select(WCC->Hdr->http_sock + 1, NULL, &wset, NULL, NULL) == -1) {
                                syslog(LOG_INFO, "client_write: Socket select failed (%s)\n", strerror(errno));
                                return -1;
                        }
                }

                if ((WCC->Hdr->http_sock == -1) || 
		    (res = write(WCC->Hdr->http_sock, 
				 ptr,
				 count)) == -1) {
                        syslog(LOG_INFO, "client_write: Socket write failed (%s)\n", strerror(errno));
			wc_backtrace(LOG_INFO);
                        return res;
                }
                count -= res;
		ptr += res;
        }

	return StrLength(WCC->WBuf);
}


/*
 * lingering_close() a`la Apache. see
 * http://httpd.apache.org/docs/2.0/misc/fin_wait_2.html for rationale
 */
int lingering_close(int fd)
{
	char buf[SIZ];
	int i;
	fd_set set;
	struct timeval tv, start;

	gettimeofday(&start, NULL);
	if (fd == -1)
		return -1;
	shutdown(fd, 1);
	do {
		do {
			gettimeofday(&tv, NULL);
			tv.tv_sec = SLEEPING - (tv.tv_sec - start.tv_sec);
			tv.tv_usec = start.tv_usec - tv.tv_usec;
			if (tv.tv_usec < 0) {
				tv.tv_sec--;
				tv.tv_usec += 1000000;
			}
			FD_ZERO(&set);
			FD_SET(fd, &set);
			i = select(fd + 1, &set, NULL, NULL, &tv);
		} while (i == -1 && errno == EINTR);

		if (i <= 0)
			break;

		i = read(fd, buf, sizeof buf);
	} while (i != 0 && (i != -1 || errno == EINTR));

	return close(fd);
}

void
HttpNewModule_TCPSOCKETS
(ParsedHttpHdrs *httpreq)
{

	httpreq->ReadBuf = NewStrBufPlain(NULL, SIZ * 4);
}

void
HttpDetachModule_TCPSOCKETS
(ParsedHttpHdrs *httpreq)
{

	FlushStrBuf(httpreq->ReadBuf);
	ReAdjustEmptyBuf(httpreq->ReadBuf, 4 * SIZ, SIZ);
}

void
HttpDestroyModule_TCPSOCKETS
(ParsedHttpHdrs *httpreq)
{

	FreeStrBuf(&httpreq->ReadBuf);
}


void
SessionNewModule_TCPSOCKETS
(wcsession *sess)
{
	sess->CLineBuf = NewStrBuf();
	sess->MigrateReadLineBuf = NewStrBuf();
}

void 
SessionDestroyModule_TCPSOCKETS
(wcsession *sess)
{
	FreeStrBuf(&sess->CLineBuf);
	FreeStrBuf(&sess->ReadBuf);
	sess->connected = 0;
	sess->ReadPos = NULL;
	FreeStrBuf(&sess->MigrateReadLineBuf);
	if (sess->serv_sock > 0) {
		syslog(LOG_DEBUG, "Closing socket %d", sess->serv_sock);
		close(sess->serv_sock);
	}
	sess->serv_sock = -1;
}
