#if !defined(lint)
static char rcsid[] = "$Id$";
#endif

/*
 * xdr_stdio.c, XDR implementation on standard i/o file.
 *
 * This set of routines implements a XDR on a stdio stream.
 * XDR_ENCODE serializes onto the stream, XDR_DECODE de-serializes
 * from the stream.
 *
 * Based on Sun sources from the portable distribution:
 *
 * @(#)xdr_stdio.c    1.1 87/11/04 3.9 RPCSRC
 * @(#)xdr_stdio.c 1.16 87/08/11 Copyr 1984 Sun Micro
 * Copyright (C) 1984, Sun Microsystems, Inc.
 *
 *  UCAR/Unidata modifications for netcdf:
 *      _destroy closes the stream.
 *      current stream position cached in x_public
 *             (assumes caddr_t can hold a long)
 *      last op cached in x_handy
 */

#include <stdio.h>

#include "local_nc.h" /* prototypes for NCadvis, nc_error */
            /* also obtains <stdio.h>, <rpc/types.h>, &
            * <rpc/xdr.h> */
#ifdef H4_HAVE_FCNTL_H
#include    <fcntl.h>   /* O_BINARY */
#endif
#ifdef DOS_FS
#define USE_BFLAG
#endif

#ifdef USE_XDRNCSTDIO


#define XDRNC_LASTOP(xdrs) (*((enum xdr_op*)&((xdrs)->x_handy)))
#define XDRNC_POS(xdrs) (*((long*)&((xdrs)->x_public)))


static bool_t    xdrNCstdio_getlong();
static bool_t    xdrNCstdio_putlong();
static bool_t    xdrNCstdio_getbytes();
static bool_t    xdrNCstdio_putbytes();
static u_long    xdrNCstdio_getpos();
static bool_t    xdrNCstdio_setpos();
static int32_t  *xdrNCstdio_inline();
static void      xdrNCstdio_destroy();

/*
 * Ops vector for stdio type XDR
 */
static struct xdr_ops    xdrNCstdio_ops = {
    xdrNCstdio_getlong,   /* deserialize a long int */
    xdrNCstdio_putlong,   /* serialize a long int */
    xdrNCstdio_getbytes,  /* deserialize counted bytes */
    xdrNCstdio_putbytes,  /* serialize counted bytes */
    xdrNCstdio_getpos,    /* get offset in the stream */
    xdrNCstdio_setpos,    /* set offset in the stream */
    xdrNCstdio_inline,    /* prime stream for inline macros */
    xdrNCstdio_destroy    /* destroy stream */
};

/*
 * Initialize a stdio xdr stream.
 * Sets the xdr stream handle xdrs for use on the stream file.
 * Operation flag is set to op.
 */
void
xdrNCstdio_create(xdrs, file, op)
    register XDR *xdrs;
    FILE *file;
    enum xdr_op op;
{
    xdrs->x_op = op;
    xdrs->x_ops = &xdrNCstdio_ops;
    xdrs->x_private = (caddr_t)file;
    xdrs->x_handy = 0;
    xdrs->x_base = 0;
    XDRNC_LASTOP(xdrs) = XDR_FREE ;
    XDRNC_POS(xdrs) = ftell(file) ;
}

/*
 * Destroy a NCstdio xdr stream.
 * Cleans up the xdr stream handle xdrs previously set up by xdrNCstdio_create.
 * This function closes the stream.
 */
static void
xdrNCstdio_destroy(xdrs)
    register XDR *xdrs;
{
    (void)fclose((FILE *)xdrs->x_private);
}

static bool_t
xdrNCstdio_getlong(xdrs, lp)
    XDR *xdrs;
    register long *lp;
{
    if (fread((caddr_t)lp, sizeof(long), 1, (FILE *)xdrs->x_private) != 1)
    {
        XDRNC_POS(xdrs) = ftell((FILE *)xdrs->x_private);
        return (FALSE);
    }
#ifndef H4_WORDS_BIGENDIAN
    *lp = ntohl(*lp);
#endif
    XDRNC_POS(xdrs) += sizeof(long) ;
    return (TRUE);
}

static bool_t
xdrNCstdio_putlong(xdrs, lp)
    XDR *xdrs;
    long *lp;
{
#ifndef H4_WORDS_BIGENDIAN
    long mycopy = htonl(*lp);
    lp = &mycopy;
#endif

    if (fwrite((caddr_t)lp, sizeof(long), 1, (FILE *)xdrs->x_private) != 1)
    {
        XDRNC_POS(xdrs) = ftell((FILE *)xdrs->x_private);
        return (FALSE);
    }
    XDRNC_POS(xdrs) += sizeof(long) ;
    return (TRUE);
}

static bool_t
xdrNCstdio_getbytes(xdrs, addr, len)
    XDR *xdrs;
    caddr_t addr;
    u_int len;
{
    if ((len != 0) && (fread(addr, (int)len, 1, (FILE *)xdrs->x_private) != 1))
    {
        XDRNC_POS(xdrs) = ftell((FILE *)xdrs->x_private);
        return (FALSE);
    }
    XDRNC_POS(xdrs) += len ;
    return (TRUE);
}

static bool_t
xdrNCstdio_putbytes(xdrs, addr, len)
    XDR *xdrs;
    caddr_t addr;
    u_int len;
{

    if ((len != 0) && (fwrite(addr, (int)len, 1, (FILE *)xdrs->x_private) != 1))
    {
        XDRNC_POS(xdrs) = ftell((FILE *)xdrs->x_private);
        return (FALSE);
    }
    XDRNC_POS(xdrs) += len ;
    return (TRUE);
}

static u_long
xdrNCstdio_getpos(xdrs)
    XDR *xdrs;
{
    XDRNC_POS(xdrs) = ftell((FILE *)xdrs->x_private);
    return ((u_long)XDRNC_POS(xdrs));
}

static bool_t
xdrNCstdio_setpos(xdrs, pos)
    XDR *xdrs;
    u_int pos;
{
    if(xdrs->x_op == XDRNC_LASTOP(xdrs) && pos == XDRNC_POS(xdrs))
        return TRUE ;
    /* else */
    XDRNC_LASTOP(xdrs) = xdrs->x_op ;
    if (fseek((FILE *)xdrs->x_private,(long)pos, 0) < 0)
    {
        XDRNC_POS(xdrs) = ftell((FILE *)xdrs->x_private);
        return (FALSE);
    }
    /* else */
    XDRNC_POS(xdrs) = pos ;
    return TRUE ;
}

/*ARGSUSED*/
static int32_t *
xdrNCstdio_inline(xdrs, len)
    XDR *xdrs;
    u_int len;
{

    /*
     * Must do some work to implement this: must insure
     * enough data in the underlying stdio buffer,
     * that the buffer is aligned so that we can indirect through a
     * long *, and stuff this pointer in xdrs->x_buf.  Doing
     * a fread or fwrite to a scratch buffer would defeat
     * most of the gains to be had here and require storage
     * management on this buffer, so we don't do this.
     */
    return (NULL);
}
#else

/*
 * Destroy a stdio xdr stream.
 * Cleans up the xdr stream handle xdrs previously set up by xdrstdio_create.
 * This function closes the stream, while the default
 * library function, xdrstdio_destroy() which merely flushes it.
 */
static void
xdrNCstdio_destroy(xdrs)
    XDR *xdrs;
{
    (void)fclose((FILE *)xdrs->x_private);
}

static bool_t
xdrNCstdio_setpos(xdrs, pos)
    XDR *xdrs;
    u_int pos;
{

    static XDR *last = NULL ;
    static enum xdr_op lastop = XDR_FREE ;

    if(xdrs == last && xdrs->x_op == lastop && pos == xdr_getpos(xdrs))
        return TRUE ;
    /* else */
    last = xdrs ;
    lastop = xdrs->x_op ;
    if (fseek((FILE *)xdrs->x_private,(long)pos, 0) < 0)
    {
        return (FALSE);
    }
    /* else */
    return TRUE ;
}

#endif /* USE_XDRNCSTDIO */


/********/

#ifdef H4_HAVE_UNISTD_H
#include <unistd.h> /* access(), F_OK */
#endif

#ifndef F_OK
#define F_OK    0
#endif

#include "netcdf.h" /* NC_ */
#include "local_nc.h" /* prototypes for NCadvis, nc_error */

#ifndef USE_BFLAG     /* Doesn't Understand the "b" (binary flag to fopen) */
#define CREAT_FOPENFLAGS "w+"
#define WRITE_FOPENFLAGS "r+"
#define NOWRITE_FOPENFLAGS "r"
#else
#define CREAT_FOPENFLAGS "w+b"
#define WRITE_FOPENFLAGS "r+b"
#define NOWRITE_FOPENFLAGS "rb"
#endif /* !USE_BFLAG */


/*
 * "sync" (flush) xdr stream.
 */
int
NCxdrfile_sync(xdrs)
    XDR *xdrs;
{
    /* assumes xdrstdio, violates layering */
    FILE *fp = (FILE *)xdrs->x_private ;
    if(fflush(fp) == 0)
        return 0 ; /* success */
    /* else, failure */
    return -1 ;
}


int
NCxdrfile_create(xdrs, path, ncmode)
XDR *xdrs ;
const char *path ;
int ncmode ;
{
    char *fmode ;
    FILE *fp ;
    enum xdr_op op ;

    switch(ncmode & 0x0f) {
    case NC_NOCLOBBER :
        if( access(path, F_OK) != -1 )
        {
            NCadvise(NC_EEXIST, "\"%s\": File exists", path) ;
            return(-1) ;
        }
        /* fall into */
    case NC_CLOBBER :
        fmode = CREAT_FOPENFLAGS ;
        break ;
    case NC_WRITE :
        fmode = WRITE_FOPENFLAGS ;
        break ;
    case NC_NOWRITE :
        fmode = NOWRITE_FOPENFLAGS ;
        break ;
    default:
        NCadvise(NC_EINVAL, "Bad flag %0x", ncmode & 0x0f) ;
        return(-1) ;
    }

#ifdef DOS_FS
    /*
    * set default mode to binary to suppress the expansion of
    * 0x0f into CRLF
    */
    if(_fmode != O_BINARY)
        _fmode = O_BINARY ;
#endif
    fp = fopen(path, fmode) ;
    if( fp == NULL )
    {
        nc_serror("filename \"%s\"", path) ;
        return(-1) ;
    } /* else */

    if( ncmode & NC_CREAT )
    {
        op = XDR_ENCODE ;
    } else {
        op = XDR_DECODE ;
    }

#ifndef USE_XDRNCSTDIO
    xdrstdio_create(xdrs, fp, op) ;
    xdrs->x_ops->x_destroy = xdrNCstdio_destroy ;
    xdrs->x_ops->x_setpostn = xdrNCstdio_setpos ;
#else
    xdrNCstdio_create(xdrs, fp, op) ;
#endif

    return fileno(fp) ;
}
