/***************************************************************************/
/*									   */
/* ftplib.c - callable ftp access routines				   */
/* Copyright (C) 1996-2000 Thomas Pfau, pfau@cnj.digex.net		   */
/*	73 Catherine Street, South Bound Brook, NJ, 08880		   */
/*									   */
/* This library is free software; you can redistribute it and/or	   */
/* modify it under the terms of the GNU Library General Public		   */
/* License as published by the Free Software Foundation; either		   */
/* version 2 of the License, or (at your option) any later version.	   */
/* 									   */
/* This library 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	   */
/* Library General Public License for more details.			   */
/* 									   */
/* You should have received a copy of the GNU Library General Public	   */
/* License along with this progam; if not, write to the			   */
/* Free Software Foundation, Inc., 59 Temple Place - Suite 330,		   */
/* Boston, MA 02111-1307, USA.						   */
/* 									   */
/***************************************************************************/

#if defined(__unix__) || defined(__VMS) || defined (__APPLE__) || defined (unix)
#include <unistd.h>
#endif
#if defined(_WIN32)
#include <winsock2.h>
#include <windows.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <ctype.h>
#if defined(__unix__) || defined (__APPLE__) || defined (unix)
#include <sys/time.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <arpa/inet.h>
#elif defined(VMS)
#include <types.h>
#include <socket.h>
#include <in.h>
#include <netdb.h>
#include <inet.h>
#elif defined(_WIN32)
#include <ws2tcpip.h>
#endif

#define BUILDING_LIBRARY
#include "ftplib.h"

#if defined(_WIN32)
#define SETSOCKOPT_OPTVAL_TYPE (const char *)
#else
#define SETSOCKOPT_OPTVAL_TYPE (void *)
#endif

#if defined(__osf__)
#define SOCKLEN_TYPE int
#else
#define SOCKLEN_TYPE socklen_t
#endif

#define FTPLIB_BUFSIZ 8192
#define ACCEPT_TIMEOUT 30

#define FTPLIB_CONTROL 0
#define FTPLIB_READ 1
#define FTPLIB_WRITE 2

#if !defined FTPLIB_DEFMODE
#define FTPLIB_DEFMODE FTPLIB_PASSIVE
#endif

struct NetBuf {
    char *cput,*cget;
    int handle;
    int cavail,cleft;
    char *buf;
    int dir;
    netbuf *ctrl;
    netbuf *data;    
    int cmode;
    struct timeval idletime;
    FtpCallback idlecb;
    void *idlearg;
    int xfered;
    int cbbytes;
    int xfered1;
    char response[256];
};

static char *version =
    "ftplib Release 3.1-1 9/16/00, copyright 1996-2000 Thomas Pfau";

int ftplib_debug = 0;

#if defined(__unix__) || defined(VMS) || defined (__APPLE__) || defined (unix)
#define net_read read
#define net_write write
#define net_close close
#elif defined(_WIN32)
#define net_read(x,y,z) recv(x,y,z,0)
#define net_write(x,y,z) send(x,y,z,0)
#define net_close closesocket
#endif

#if defined(NEED_MEMCCPY)
/*
 * VAX C does not supply a memccpy routine so I provide my own
 */
void *memccpy(void *dest, const void *src, int c, size_t n)
{
    int i=0;
    const unsigned char *ip=src;
    unsigned char *op=dest;

    while (i < n)
    {
	if ((*op++ = *ip++) == c)
	    break;
	i++;
    }
    if (i == n)
	return NULL;
    return op;
}
#endif
#if defined(NEED_STRDUP)
/*
 * strdup - return a malloc'ed copy of a string
 */
char *strdup(const char *src)
{
    int l = strlen(src) + 1;
    char *dst = malloc(l);
    if (dst)
        strcpy(dst,src);
    return dst;
}
#endif

/*
 * socket_wait - wait for socket to receive or flush data
 *
 * return 1 if no user callback, otherwise, return value returned by
 * user callback
 */
static int socket_wait(netbuf *ctl)
{
    fd_set fd,*rfd = NULL,*wfd = NULL;
    struct timeval tv;
    int rv = 0;
    if ((ctl->dir == FTPLIB_CONTROL) || (ctl->idlecb == NULL))
	return 1;
    if (ctl->dir == FTPLIB_WRITE)
	wfd = &fd;
    else
	rfd = &fd;
    FD_ZERO(&fd);
    do
    {
	FD_SET(ctl->handle,&fd);
	tv = ctl->idletime;
	rv = select(ctl->handle+1, rfd, wfd, NULL, &tv);
	if (rv == -1)
	{
	    rv = 0;
	    strncpy(ctl->ctrl->response, strerror(errno),
                    sizeof(ctl->ctrl->response));
	    break;
	}
	else if (rv > 0)
	{
	    rv = 1;
	    break;
	}
    }
    while ((rv = ctl->idlecb(ctl, ctl->xfered, ctl->idlearg)));
    return rv;
}

/*
 * read a line of text
 *
 * return -1 on error or bytecount
 */
static int readline(char *buf,int max,netbuf *ctl)
{
    int x,retval = 0;
    char *end,*bp=buf;
    int eof = 0;

    if ((ctl->dir != FTPLIB_CONTROL) && (ctl->dir != FTPLIB_READ))
	return -1;
    if (max == 0)
	return 0;
    do
    {
    	if (ctl->cavail > 0)
    	{
	    x = (max >= ctl->cavail) ? ctl->cavail : max-1;
	    end = (char *)memccpy(bp,ctl->cget,'\n',x);
	    if (end != NULL)
		x = end - bp;
	    retval += x;
	    bp += x;
	    *bp = '\0';
	    max -= x;
	    ctl->cget += x;
	    ctl->cavail -= x;
	    if (end != NULL)
	    {
		bp -= 2;
		if (strcmp(bp,"\r\n") == 0)
		{
		    *bp++ = '\n';
		    *bp++ = '\0';
		    --retval;
		}
	    	break;
	    }
    	}
    	if (max == 1)
    	{
	    *buf = '\0';
	    break;
    	}
    	if (ctl->cput == ctl->cget)
    	{
	    ctl->cput = ctl->cget = ctl->buf;
	    ctl->cavail = 0;
	    ctl->cleft = FTPLIB_BUFSIZ;
    	}
	if (eof)
	{
	    if (retval == 0)
		retval = -1;
	    break;
	}
	if (!socket_wait(ctl))
	    return retval;
    	if ((x = net_read(ctl->handle,ctl->cput,ctl->cleft)) == -1)
    	{
	    perror("read");
	    retval = -1;
	    break;
    	}
	if (x == 0)
	    eof = 1;
    	ctl->cleft -= x;
    	ctl->cavail += x;
    	ctl->cput += x;
    }
    while (1);
    return retval;
}

/*
 * write lines of text
 *
 * return -1 on error or bytecount
 */
static int writeline(char *buf, int len, netbuf *nData)
{
    int x, nb=0, w;
    char *ubp = buf, *nbp;
    char lc=0;

    if (nData->dir != FTPLIB_WRITE)
	return -1;
    nbp = nData->buf;
    for (x=0; x < len; x++)
    {
	if ((*ubp == '\n') && (lc != '\r'))
	{
	    if (nb == FTPLIB_BUFSIZ)
	    {
		if (!socket_wait(nData))
		    return x;
		w = net_write(nData->handle, nbp, FTPLIB_BUFSIZ);
		if (w != FTPLIB_BUFSIZ)
		{
		    printf("net_write(1) returned %d, errno = %d\n", w, errno);
		    return(-1);
		}
		nb = 0;
	    }
	    nbp[nb++] = '\r';
	}
	if (nb == FTPLIB_BUFSIZ)
	{
	    if (!socket_wait(nData))
		return x;
	    w = net_write(nData->handle, nbp, FTPLIB_BUFSIZ);
	    if (w != FTPLIB_BUFSIZ)
	    {
		printf("net_write(2) returned %d, errno = %d\n", w, errno);
		return(-1);
	    }
	    nb = 0;
	}
	nbp[nb++] = lc = *ubp++;
    }
    if (nb)
    {
	if (!socket_wait(nData))
	    return x;
	w = net_write(nData->handle, nbp, nb);
	if (w != nb)
	{
	    printf("net_write(3) returned %d, errno = %d\n", w, errno);
	    return(-1);
	}
    }
    return len;
}

/*
 * read a response from the server
 *
 * return 0 if first char doesn't match
 * return 1 if first char matches
 */
static int readresp(char c, netbuf *nControl)
{
    char match[5];
    if (readline(nControl->response,256,nControl) == -1)
    {
	perror("Control socket read failed");
	return 0;
    }
    if (ftplib_debug > 1)
	fprintf(stderr,"%s",nControl->response);
    if (nControl->response[3] == '-')
    {
	strncpy(match,nControl->response,3);
	match[3] = ' ';
	match[4] = '\0';
	do
	{
	    if (readline(nControl->response,256,nControl) == -1)
	    {
		perror("Control socket read failed");
		return 0;
	    }
	    if (ftplib_debug > 1)
		fprintf(stderr,"%s",nControl->response);
	}
	while (strncmp(nControl->response,match,4));
    }
    if (nControl->response[0] == c)
	return 1;
    return 0;
}

/*
 * FtpInit for stupid operating systems that require it (Windows NT)
 */
void FtpInit(void)
{
#if defined(_WIN32)
    WORD wVersionRequested;
    WSADATA wsadata;
    int err;
    wVersionRequested = MAKEWORD(1,1);
    if ((err = WSAStartup(wVersionRequested,&wsadata)) != 0)
	fprintf(stderr,"Network failed to start: %d\n",err);
#endif
}

/*
 * FtpLastResponse - return a pointer to the last response received
 */
char *FtpLastResponse(netbuf *nControl)
{
    if ((nControl) && (nControl->dir == FTPLIB_CONTROL))
    	return nControl->response;
    return NULL;
}

/*
 * FtpConnect - connect to remote server
 *
 * return 1 if connected, 0 if not
 */
int FtpConnect(const char *host, netbuf **nControl)
{
    int sControl;
    struct sockaddr_in sin;
    struct hostent *phe;
    struct servent *pse;
    int on=1;
    netbuf *ctrl;
    char *lhost;
    char *pnum;

    memset(&sin,0,sizeof(sin));
    sin.sin_family = AF_INET;
    lhost = strdup(host);
    pnum = strchr(lhost,':');
    if (pnum == NULL)
    {
#if defined(VMS)
    	sin.sin_port = htons(21);
#else
    	if ((pse = getservbyname("ftp","tcp")) == NULL)
    	{
	    perror("getservbyname");
	    return 0;
    	}
    	sin.sin_port = pse->s_port;
#endif
    }
    else
    {
	*pnum++ = '\0';
	if (isdigit(*pnum))
	    sin.sin_port = htons(atoi(pnum));
	else
	{
	    pse = getservbyname(pnum,"tcp");
	    sin.sin_port = pse->s_port;
	}
    }
    if ((sin.sin_addr.s_addr = inet_addr(lhost)) == -1)
    {
    	if ((phe = gethostbyname(lhost)) == NULL)
    	{
	    perror("gethostbyname");
	    return 0;
    	}
    	memcpy((char *)&sin.sin_addr, phe->h_addr, phe->h_length);
    }
    free(lhost);
    sControl = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
    if (sControl == -1)
    {
	perror("socket");
	return 0;
    }
    if (setsockopt(sControl,SOL_SOCKET,SO_REUSEADDR,
		   SETSOCKOPT_OPTVAL_TYPE &on, sizeof(on)) == -1)
    {
	perror("setsockopt");
	net_close(sControl);
	return 0;
    }
    if (connect(sControl, (struct sockaddr *)&sin, sizeof(sin)) == -1)
    {
	perror("connect");
	net_close(sControl);
	return 0;
    }
    ctrl = (netbuf *)calloc(1,sizeof(netbuf));
    if (ctrl == NULL)
    {
	perror("calloc");
	net_close(sControl);
	return 0;
    }
    ctrl->buf = (char *)malloc(FTPLIB_BUFSIZ);
    if (ctrl->buf == NULL)
    {
	perror("calloc");
	net_close(sControl);
	free(ctrl);
	return 0;
    }
    ctrl->handle = sControl;
    ctrl->dir = FTPLIB_CONTROL;
    ctrl->ctrl = NULL;
    ctrl->cmode = FTPLIB_DEFMODE;
    ctrl->idlecb = NULL;
    ctrl->idletime.tv_sec = ctrl->idletime.tv_usec = 0;
    ctrl->idlearg = NULL;
    ctrl->xfered = 0;
    ctrl->xfered1 = 0;
    ctrl->cbbytes = 0;
    if (readresp('2', ctrl) == 0)
    {
	net_close(sControl);
	free(ctrl->buf);
	free(ctrl);
	return 0;
    }
    *nControl = ctrl;
    return 1;
}

/*
 * FtpOptions - change connection options
 *
 * returns 1 if successful, 0 on error
 */
int FtpOptions(int opt, long val, netbuf *nControl)
{
    int v,rv=0;
    switch (opt)
    {
      case FTPLIB_CONNMODE:
	v = (int) val;
	if ((v == FTPLIB_PASSIVE) || (v == FTPLIB_PORT))
	{
	    nControl->cmode = v;
	    rv = 1;
	}
	break;
      case FTPLIB_CALLBACK:
	nControl->idlecb = (FtpCallback) val;
	rv = 1;
	break;
      case FTPLIB_IDLETIME:
	v = (int) val;
	rv = 1;
	nControl->idletime.tv_sec = v / 1000;
	nControl->idletime.tv_usec = (v % 1000) * 1000;
	break;
      case FTPLIB_CALLBACKARG:
	rv = 1;
	nControl->idlearg = (void *) val;
	break;
      case FTPLIB_CALLBACKBYTES:
        rv = 1;
        nControl->cbbytes = (int) val;
        break;
    }
    return rv;
}

/*
 * FtpSendCmd - send a command and wait for expected response
 *
 * return 1 if proper response received, 0 otherwise
 */
static int FtpSendCmd(const char *cmd, char expresp, netbuf *nControl)
{
    char buf[256];
    if (nControl->dir != FTPLIB_CONTROL)
	return 0;
    if (ftplib_debug > 2)
	fprintf(stderr,"%s\n",cmd);
    if ((strlen(cmd) + 3) > sizeof(buf))
        return 0;
    sprintf(buf,"%s\r\n",cmd);
    if (net_write(nControl->handle,buf,strlen(buf)) <= 0)
    {
	perror("write");
	return 0;
    }
    return readresp(expresp, nControl);
}

/*
 * FtpLogin - log in to remote server
 *
 * return 1 if logged in, 0 otherwise
 */
int FtpLogin(const char *user, const char *pass, netbuf *nControl)
{
    char tempbuf[64];

    if (((strlen(user) + 7) > sizeof(tempbuf)) ||
        ((strlen(pass) + 7) > sizeof(tempbuf)))
        return 0;
    sprintf(tempbuf,"USER %s",user);
    if (!FtpSendCmd(tempbuf,'3',nControl))
    {
	if (nControl->response[0] == '2')
	    return 1;
	return 0;
    }
    sprintf(tempbuf,"PASS %s",pass);
    return FtpSendCmd(tempbuf,'2',nControl);
}

/*
 * FtpOpenPort - set up data connection
 *
 * return 1 if successful, 0 otherwise
 */
static int FtpOpenPort(netbuf *nControl, netbuf **nData, int mode, int dir)
{
    int sData;
    union {
	struct sockaddr sa;
	struct sockaddr_in in;
    } sin;
    struct linger lng = { 0, 0 };
    SOCKLEN_TYPE l;
    int on=1;
    netbuf *ctrl;
    char *cp;
    unsigned int v[6];
    char buf[256];

    if (nControl->dir != FTPLIB_CONTROL)
	return -1;
    if ((dir != FTPLIB_READ) && (dir != FTPLIB_WRITE))
    {
	sprintf(nControl->response, "Invalid direction %d\n", dir);
	return -1;
    }
    if ((mode != FTPLIB_ASCII) && (mode != FTPLIB_IMAGE))
    {
	sprintf(nControl->response, "Invalid mode %c\n", mode);
	return -1;
    }
    l = sizeof(sin);
    if (nControl->cmode == FTPLIB_PASSIVE)
    {
	memset(&sin, 0, l);
	sin.in.sin_family = AF_INET;
	if (!FtpSendCmd("PASV",'2',nControl))
	    return -1;
	cp = strchr(nControl->response,'(');
	if (cp == NULL)
	    return -1;
	cp++;
	sscanf(cp,"%u,%u,%u,%u,%u,%u",&v[2],&v[3],&v[4],&v[5],&v[0],&v[1]);
	sin.sa.sa_data[2] = v[2];
	sin.sa.sa_data[3] = v[3];
	sin.sa.sa_data[4] = v[4];
	sin.sa.sa_data[5] = v[5];
	sin.sa.sa_data[0] = v[0];
	sin.sa.sa_data[1] = v[1];
    }
    else
    {
	if (getsockname(nControl->handle, &sin.sa, &l) < 0)
	{
	    perror("getsockname");
	    return 0;
	}
    }
    sData = socket(PF_INET,SOCK_STREAM,IPPROTO_TCP);
    if (sData == -1)
    {
	perror("socket");
	return -1;
    }
    if (setsockopt(sData,SOL_SOCKET,SO_REUSEADDR,
		   SETSOCKOPT_OPTVAL_TYPE &on,sizeof(on)) == -1)
    {
	perror("setsockopt");
	net_close(sData);
	return -1;
    }
    if (setsockopt(sData,SOL_SOCKET,SO_LINGER,
		   SETSOCKOPT_OPTVAL_TYPE &lng,sizeof(lng)) == -1)
    {
	perror("setsockopt");
	net_close(sData);
	return -1;
    }
    if (nControl->cmode == FTPLIB_PASSIVE)
    {
	if (connect(sData, &sin.sa, sizeof(sin.sa)) == -1)
	{
	    perror("connect");
	    net_close(sData);
	    return -1;
	}
    }
    else
    {
	sin.in.sin_port = 0;
	if (bind(sData, &sin.sa, sizeof(sin)) == -1)
	{
	    perror("bind");
	    net_close(sData);
	    return 0;
	}
	if (listen(sData, 1) < 0)
	{
	    perror("listen");
	    net_close(sData);
	    return 0;
	}
	if (getsockname(sData, &sin.sa, &l) < 0)
	    return 0;
	sprintf(buf, "PORT %d,%d,%d,%d,%d,%d",
		(unsigned char) sin.sa.sa_data[2],
		(unsigned char) sin.sa.sa_data[3],
		(unsigned char) sin.sa.sa_data[4],
		(unsigned char) sin.sa.sa_data[5],
		(unsigned char) sin.sa.sa_data[0],
		(unsigned char) sin.sa.sa_data[1]);
	if (!FtpSendCmd(buf,'2',nControl))
	{
	    net_close(sData);
	    return 0;
	}
    }
    ctrl = (netbuf *)calloc(1,sizeof(netbuf));
    if (ctrl == NULL)
    {
	perror("calloc");
	net_close(sData);
	return -1;
    }
    if ((mode == 'A') && ((ctrl->buf = (char *)malloc(FTPLIB_BUFSIZ)) == NULL))
    {
	perror("calloc");
	net_close(sData);
	free(ctrl);
	return -1;
    }
    ctrl->handle = sData;
    ctrl->dir = dir;
    ctrl->idletime = nControl->idletime;
    ctrl->idlearg = nControl->idlearg;
    ctrl->xfered = 0;
    ctrl->xfered1 = 0;
    ctrl->cbbytes = nControl->cbbytes;
    if (ctrl->idletime.tv_sec || ctrl->idletime.tv_usec || ctrl->cbbytes)
	ctrl->idlecb = nControl->idlecb;
    else
	ctrl->idlecb = NULL;
    *nData = ctrl;
    return 1;
}

/*
 * FtpAcceptConnection - accept connection from server
 *
 * return 1 if successful, 0 otherwise
 */
static int FtpAcceptConnection(netbuf *nData, netbuf *nControl)
{
    int sData;
    struct sockaddr addr;
    SOCKLEN_TYPE l;
    int i;
    struct timeval tv;
    fd_set mask;
    int rv;

    FD_ZERO(&mask);
    FD_SET(nControl->handle, &mask);
    FD_SET(nData->handle, &mask);
    tv.tv_usec = 0;
    tv.tv_sec = ACCEPT_TIMEOUT;
    i = nControl->handle;
    if (i < nData->handle)
	i = nData->handle;
    i = select(i+1, &mask, NULL, NULL, &tv);
    if (i == -1)
    {
        strncpy(nControl->response, strerror(errno),
                sizeof(nControl->response));
        net_close(nData->handle);
        nData->handle = 0;
        rv = 0;
    }
    else if (i == 0)
    {
	strcpy(nControl->response, "timed out waiting for connection");
	net_close(nData->handle);
	nData->handle = 0;
	rv = 0;
    }
    else
    {
	if (FD_ISSET(nData->handle, &mask))
	{
	    l = sizeof(addr);
	    sData = accept(nData->handle, &addr, &l);
	    i = errno;
	    net_close(nData->handle);
	    if (sData > 0)
	    {
		rv = 1;
		nData->handle = sData;
	    }
	    else
	    {
		strncpy(nControl->response, strerror(i),
                        sizeof(nControl->response));
		nData->handle = 0;
		rv = 0;
	    }
	}
	else if (FD_ISSET(nControl->handle, &mask))
	{
	    net_close(nData->handle);
	    nData->handle = 0;
	    readresp('2', nControl);
	    rv = 0;
	}
    }
    return rv;	
}

/*
 * FtpAccess - return a handle for a data stream
 *
 * return 1 if successful, 0 otherwise
 */
int FtpAccess(const char *path, int typ, int mode, netbuf *nControl,
    netbuf **nData)
{
    char buf[256];
    int dir;
    if ((path == NULL) &&
        ((typ == FTPLIB_FILE_WRITE) || (typ == FTPLIB_FILE_READ)))
    {
	sprintf(nControl->response,
                "Missing path argument for file transfer\n");
	return 0;
    }
    sprintf(buf, "TYPE %c", mode);
    if (!FtpSendCmd(buf, '2', nControl))
	return 0;
    switch (typ)
    {
      case FTPLIB_DIR:
	strcpy(buf,"NLST");
	dir = FTPLIB_READ;
	break;
      case FTPLIB_DIR_VERBOSE:
	strcpy(buf,"LIST");
	dir = FTPLIB_READ;
	break;
      case FTPLIB_FILE_READ:
	strcpy(buf,"RETR");
	dir = FTPLIB_READ;
	break;
      case FTPLIB_FILE_WRITE:
	strcpy(buf,"STOR");
	dir = FTPLIB_WRITE;
	break;
      default:
	sprintf(nControl->response, "Invalid open type %d\n", typ);
	return 0;
    }
    if (path != NULL)
    {
        int i = strlen(buf);
        buf[i++] = ' ';
        if ((strlen(path) + i) >= sizeof(buf))
            return 0;
        strcpy(&buf[i],path);
    }
    if (FtpOpenPort(nControl, nData, mode, dir) == -1)
	return 0;
    if (!FtpSendCmd(buf, '1', nControl))
    {
	FtpClose(*nData);
	*nData = NULL;
	return 0;
    }
    (*nData)->ctrl = nControl;
    nControl->data = *nData;
    if (nControl->cmode == FTPLIB_PORT)
    {
	if (!FtpAcceptConnection(*nData,nControl))
	{
	    FtpClose(*nData);
	    *nData = NULL;
	    nControl->data = NULL;
	    return 0;
	}
    }
    return 1;
}

/*
 * FtpRead - read from a data connection
 */
int FtpRead(void *buf, int max, netbuf *nData)
{
    int i;
    if (nData->dir != FTPLIB_READ)
	return 0;
    if (nData->buf)
        i = readline((char *)buf, max, nData);
    else
    {
        i = socket_wait(nData);
	if (i != 1)
	    return 0;
        i = net_read(nData->handle, buf, max);
    }
    if (i == -1)
	return 0;
    nData->xfered += i;
    if (nData->idlecb && nData->cbbytes)
    {
        nData->xfered1 += i;
        if (nData->xfered1 > nData->cbbytes)
        {
	    if (nData->idlecb(nData, nData->xfered, nData->idlearg) == 0)
		return 0;
            nData->xfered1 = 0;
        }
    }
    return i;
}

/*
 * FtpWrite - write to a data connection
 */
int FtpWrite(void *buf, int len, netbuf *nData)
{
    int i;
    if (nData->dir != FTPLIB_WRITE)
	return 0;
    if (nData->buf)
    	i = writeline((char *)buf, len, nData);
    else
    {
        socket_wait(nData);
        i = net_write(nData->handle, buf, len);
    }
    if (i == -1)
	return 0;
    nData->xfered += i;
    if (nData->idlecb && nData->cbbytes)
    {
        nData->xfered1 += i;
        if (nData->xfered1 > nData->cbbytes)
        {
            nData->idlecb(nData, nData->xfered, nData->idlearg);
            nData->xfered1 = 0;
        }
    }
    return i;
}

/*
 * FtpClose - close a data connection
 */
int FtpClose(netbuf *nData)
{
    netbuf *ctrl;
    switch (nData->dir)
    {
      case FTPLIB_WRITE:
	/* potential problem - if buffer flush fails, how to notify user? */
	if (nData->buf != NULL)
	    writeline(NULL, 0, nData);
      case FTPLIB_READ:
	if (nData->buf)
	    free(nData->buf);
	shutdown(nData->handle,2);
	net_close(nData->handle);
	ctrl = nData->ctrl;
	free(nData);
	if (ctrl)
	{
	    ctrl->data = NULL;
	    return(readresp('2', ctrl));
	}
	return 1;
      case FTPLIB_CONTROL:
	if (nData->data)
	{
	    nData->ctrl = NULL;
	    FtpClose(nData);
	}
	net_close(nData->handle);
	free(nData);
	return 0;
    }
    return 1;
}

/*
 * FtpSite - send a SITE command
 *
 * return 1 if command successful, 0 otherwise
 */
int FtpSite(const char *cmd, netbuf *nControl)
{
    char buf[256];
    
    if ((strlen(cmd) + 7) > sizeof(buf))
        return 0;
    sprintf(buf,"SITE %s",cmd);
    if (!FtpSendCmd(buf,'2',nControl))
	return 0;
    return 1;
}

/*
 * FtpSysType - send a SYST command
 *
 * Fills in the user buffer with the remote system type.  If more
 * information from the response is required, the user can parse
 * it out of the response buffer returned by FtpLastResponse().
 *
 * return 1 if command successful, 0 otherwise
 */
int FtpSysType(char *buf, int max, netbuf *nControl)
{
    int l = max;
    char *b = buf;
    char *s;
    if (!FtpSendCmd("SYST",'2',nControl))
	return 0;
    s = &nControl->response[4];
    while ((--l) && (*s != ' '))
	*b++ = *s++;
    *b++ = '\0';
    return 1;
}

/*
 * FtpMkdir - create a directory at server
 *
 * return 1 if successful, 0 otherwise
 */
int FtpMkdir(const char *path, netbuf *nControl)
{
    char buf[256];

    if ((strlen(path) + 6) > sizeof(buf))
        return 0;
    sprintf(buf,"MKD %s",path);
    if (!FtpSendCmd(buf,'2', nControl))
	return 0;
    return 1;
}

/*
 * FtpChdir - change path at remote
 *
 * return 1 if successful, 0 otherwise
 */
int FtpChdir(const char *path, netbuf *nControl)
{
    char buf[256];

    if ((strlen(path) + 6) > sizeof(buf))
        return 0;
    sprintf(buf,"CWD %s",path);
    if (!FtpSendCmd(buf,'2',nControl))
	return 0;
    return 1;
}

/*
 * FtpCDUp - move to parent directory at remote
 *
 * return 1 if successful, 0 otherwise
 */
int FtpCDUp(netbuf *nControl)
{
    if (!FtpSendCmd("CDUP",'2',nControl))
	return 0;
    return 1;
}

/*
 * FtpRmdir - remove directory at remote
 *
 * return 1 if successful, 0 otherwise
 */
int FtpRmdir(const char *path, netbuf *nControl)
{
    char buf[256];

    if ((strlen(path) + 6) > sizeof(buf))
        return 0;
    sprintf(buf,"RMD %s",path);
    if (!FtpSendCmd(buf,'2',nControl))
	return 0;
    return 1;
}

/*
 * FtpPwd - get working directory at remote
 *
 * return 1 if successful, 0 otherwise
 */
int FtpPwd(char *path, int max, netbuf *nControl)
{
    int l = max;
    char *b = path;
    char *s;
    if (!FtpSendCmd("PWD",'2',nControl))
	return 0;
    s = strchr(nControl->response, '"');
    if (s == NULL)
	return 0;
    s++;
    while ((--l) && (*s) && (*s != '"'))
	*b++ = *s++;
    *b++ = '\0';
    return 1;
}

/*
 * FtpXfer - issue a command and transfer data
 *
 * return 1 if successful, 0 otherwise
 */
static int FtpXfer(const char *localfile, const char *path,
	netbuf *nControl, int typ, int mode)
{
    int l,c;
    char *dbuf;
    FILE *local = NULL;
    netbuf *nData;
    int rv=1;

    if (localfile != NULL)
    {
	char ac[4] = "w";
	if (typ == FTPLIB_FILE_WRITE)
	    ac[0] = 'r';
	if (mode == FTPLIB_IMAGE)
	    ac[1] = 'b';
	local = fopen(localfile, ac);
	if (local == NULL)
	{
	    strncpy(nControl->response, strerror(errno),
                    sizeof(nControl->response));
	    return 0;
	}
    }
    if (local == NULL)
	local = (typ == FTPLIB_FILE_WRITE) ? stdin : stdout;
    if (!FtpAccess(path, typ, mode, nControl, &nData))
	return 0;
    dbuf = (char *)malloc(FTPLIB_BUFSIZ);
    if (typ == FTPLIB_FILE_WRITE)
    {
	while ((l = fread(dbuf, 1, FTPLIB_BUFSIZ, local)) > 0)
	    if ((c = FtpWrite(dbuf, l, nData)) < l)
	    {
		printf("short write: passed %d, wrote %d\n", l, c);
		rv = 0;
		break;
	    }
    }
    else
    {
    	while ((l = FtpRead(dbuf, FTPLIB_BUFSIZ, nData)) > 0)
	    if (fwrite(dbuf, 1, l, local) <= 0)
	    {
		perror("localfile write");
		rv = 0;
		break;
	    }
    }
    free(dbuf);
    fflush(local);
    if (localfile != NULL)
	fclose(local);
    FtpClose(nData);
    return rv;
}

/*
 * FtpNlst - issue an NLST command and write response to output
 *
 * return 1 if successful, 0 otherwise
 */
int FtpNlst(const char *outputfile, const char *path,
	netbuf *nControl)
{
    return FtpXfer(outputfile, path, nControl, FTPLIB_DIR, FTPLIB_ASCII);
}

/*
 * FtpDir - issue a LIST command and write response to output
 *
 * return 1 if successful, 0 otherwise
 */
int FtpDir(const char *outputfile, const char *path, netbuf *nControl)
{
    return FtpXfer(outputfile, path, nControl, FTPLIB_DIR_VERBOSE, FTPLIB_ASCII);
}

/*
 * FtpSize - determine the size of a remote file
 *
 * return 1 if successful, 0 otherwise
 */
int FtpSize(const char *path, int *size, char mode, netbuf *nControl)
{
    char cmd[256];
    int resp,sz,rv=1;

    if ((strlen(path) + 7) > sizeof(cmd))
        return 0;
    sprintf(cmd, "TYPE %c", mode);
    if (!FtpSendCmd(cmd, '2', nControl))
	return 0;
    sprintf(cmd,"SIZE %s",path);
    if (!FtpSendCmd(cmd,'2',nControl))
	rv = 0;
    else
    {
	if (sscanf(nControl->response, "%d %d", &resp, &sz) == 2)
	    *size = sz;
	else
	    rv = 0;
    }   
    return rv;
}

/*
 * FtpModDate - determine the modification date of a remote file
 *
 * return 1 if successful, 0 otherwise
 */
int FtpModDate(const char *path, char *dt, int max, netbuf *nControl)
{
    char buf[256];
    int rv = 1;

    if ((strlen(path) + 7) > sizeof(buf))
        return 0;
    sprintf(buf,"MDTM %s",path);
    if (!FtpSendCmd(buf,'2',nControl))
	rv = 0;
    else
	strncpy(dt, &nControl->response[4], max);
    return rv;
}

/*
 * FtpGet - issue a GET command and write received data to output
 *
 * return 1 if successful, 0 otherwise
 */
int FtpGet(const char *outputfile, const char *path,
	char mode, netbuf *nControl)
{
    return FtpXfer(outputfile, path, nControl, FTPLIB_FILE_READ, mode);
}

/*
 * FtpPut - issue a PUT command and send data from input
 *
 * return 1 if successful, 0 otherwise
 */
int FtpPut(const char *inputfile, const char *path, char mode,
	netbuf *nControl)
{
    return FtpXfer(inputfile, path, nControl, FTPLIB_FILE_WRITE, mode);
}

/*
 * FtpRename - rename a file at remote
 *
 * return 1 if successful, 0 otherwise
 */
int FtpRename(const char *src, const char *dst, netbuf *nControl)
{
    char cmd[256];

    if (((strlen(src) + 7) > sizeof(cmd)) ||
        ((strlen(dst) + 7) > sizeof(cmd)))
        return 0;
    sprintf(cmd,"RNFR %s",src);
    if (!FtpSendCmd(cmd,'3',nControl))
	return 0;
    sprintf(cmd,"RNTO %s",dst);
    if (!FtpSendCmd(cmd,'2',nControl))
	return 0;
    return 1;
}

/*
 * FtpDelete - delete a file at remote
 *
 * return 1 if successful, 0 otherwise
 */
int FtpDelete(const char *fnm, netbuf *nControl)
{
    char cmd[256];

    if ((strlen(fnm) + 7) > sizeof(cmd))
        return 0;
    sprintf(cmd,"DELE %s",fnm);
    if (!FtpSendCmd(cmd,'2', nControl))
	return 0;
    return 1;
}

/*
 * FtpQuit - disconnect from remote
 *
 * return 1 if successful, 0 otherwise
 */
void FtpQuit(netbuf *nControl)
{
    if (nControl->dir != FTPLIB_CONTROL)
	return;
    FtpSendCmd("QUIT",'2',nControl);
    net_close(nControl->handle);
    free(nControl->buf);
    free(nControl);
}
