Geografic-Information-System/lib/vector/diglib/portable.c

/*!
   \file diglib/file.c

   \brief Vector library - portability (lower level functions)

   Lower level functions for reading/writing/manipulating vectors.
   
   (C) 2001-2009 by the GRASS Development Team

   This program is free software under the GNU General Public License
   (>=v2).  Read the file COPYING that comes with GRASS for details.

   \author Original author CERL, probably Dave Gerdes
   \author Update to GRASS 5.7 Radim Blazek
*/

#include <sys/types.h>
#include <string.h>
#include <grass/vector.h>
#include <grass/glocale.h>

extern void port_init(void);

extern int nat_dbl;
extern int nat_flt;
extern int nat_lng;
extern int nat_off_t;
extern int nat_int;
extern int nat_shrt;

extern int dbl_order;
extern int flt_order;
extern int off_t_order;
extern int lng_order;
extern int int_order;
extern int shrt_order;

extern unsigned char dbl_cnvrt[sizeof(double)];
extern unsigned char flt_cnvrt[sizeof(float)];
extern unsigned char off_t_cnvrt[sizeof(off_t)];
extern unsigned char lng_cnvrt[sizeof(long)];
extern unsigned char int_cnvrt[sizeof(int)];
extern unsigned char shrt_cnvrt[sizeof(short)];

struct Port_info *Cur_Head;

static char *buffer = NULL;
static int buf_alloced = 0;

static int buf_alloc(int needed)
{
    char *p;
    int cnt;

    if (needed <= buf_alloced)
	return (0);
    cnt = buf_alloced;
    p = dig__alloc_space(needed, &cnt, 100, buffer, 1);
    if (p == NULL)
	return (dig_out_of_memory());
    buffer = p;
    buf_alloced = cnt;
    return (0);
}

/*!
  \brief Read doubles from the Portable Vector Format

   These routines must handle any type size conversions between the
   portable format and the native machine.

   \param[out] buf data buffer
   \param cnt number of members
   \param fp pointer to struct gvfile

   \return 0 error
   \return 1 OK
*/
int dig__fread_port_D(double *buf, size_t cnt, struct gvfile * fp)
{
    unsigned int i, j;
    int ret;
    unsigned char *c1, *c2;

    if (Cur_Head->dbl_quick) {
	ret = dig_fread(buf, PORT_DOUBLE, cnt, fp);
	if (ret != (int) cnt)
	    return 0;
    }
    else {
	/* read into buffer */
	buf_alloc(cnt * PORT_DOUBLE);
	ret = dig_fread(buffer, PORT_DOUBLE, cnt, fp);
	if (ret != (int) cnt)
	    return 0;
	/* read from buffer in changed order */
	c1 = (unsigned char *)buffer;
	c2 = (unsigned char *)buf;
	for (i = 0; i < cnt; i++) {
	    for (j = 0; j < PORT_DOUBLE; j++) {
		c2[Cur_Head->dbl_cnvrt[j]] = c1[j];
	    }
	    c1 += PORT_DOUBLE;
	    c2 += sizeof(double);
	}
    }
    return 1;
}

/*!
  \brief Read floats from the Portable Vector Format

   These routines must handle any type size conversions between the
   portable format and the native machine.

   \param[out] buf data buffer
   \param cnt number of members
   \param fp pointer to struct gvfile

   \return 0 error
   \return 1 OK
*/
int dig__fread_port_F(float *buf, size_t cnt, struct gvfile * fp)
{
    unsigned int i, j;
    int ret;
    unsigned char *c1, *c2;

    if (Cur_Head->flt_quick) {
	ret = dig_fread(buf, PORT_FLOAT, cnt, fp);
	if (ret != (int) cnt)
	    return 0;
    }
    else {
	/* read into buffer */
	buf_alloc(cnt * PORT_FLOAT);
	ret = dig_fread(buffer, PORT_FLOAT, cnt, fp);
	if (ret != (int) cnt)
	    return 0;
	/* read from buffer in changed order */
	c1 = (unsigned char *)buffer;
	c2 = (unsigned char *)buf;
	for (i = 0; i < cnt; i++) {
	    for (j = 0; j < PORT_FLOAT; j++) {
		c2[Cur_Head->flt_cnvrt[j]] = c1[j];
	    }
	    c1 += PORT_FLOAT;
	    c2 += sizeof(float);
	}
    }
    return 1;
}

/*!
  \brief Read off_ts from the Portable Vector Format

   These routines must handle any type size conversions between the
   portable format and the native machine.

   \param[out] buf data buffer
   \param cnt number of members
   \param fp pointer to struct gvfile
   \param port_off_t_size offset
   \return 0 error
   \return 1 OK
*/
int dig__fread_port_O(off_t *buf, size_t cnt, struct gvfile * fp, size_t port_off_t_size)
{
    unsigned int i, j;
    int ret;
    unsigned char *c1, *c2;

    if (Cur_Head->off_t_quick) {
	if (nat_off_t == port_off_t_size) {
	    ret = dig_fread(buf, port_off_t_size, cnt, fp);
	    if (ret != (int) cnt)
		return 0;
	}
	else if (nat_off_t > port_off_t_size) {
	    /* read into buffer */
	    buf_alloc(cnt * port_off_t_size);
	    ret = dig_fread(buffer, port_off_t_size, cnt, fp);
	    if (ret != (int) cnt)
		return 0;
	    /* set buffer to zero (positive numbers) */
	    memset(buf, 0, cnt * sizeof(off_t));
	    /* read from buffer in changed order */
	    c1 = (unsigned char *)buffer;
	    c2 = (unsigned char *)buf;
	    for (i = 0; i < cnt; i++) {
		/* set to FF if the value is negative */
		if (off_t_order == ENDIAN_LITTLE) {
		    if (c1[port_off_t_size - 1] & 0x80)
			memset(c2, 0xff, sizeof(off_t));
		    memcpy(c2, c1, port_off_t_size);
		}
		else {
		    if (c1[0] & 0x80)
			memset(c2, 0xff, sizeof(off_t));
		    memcpy(c2 + nat_off_t - port_off_t_size, c1, port_off_t_size);
		}
		c1 += port_off_t_size;
		c2 += sizeof(off_t);
	    }
	}
	else if (nat_off_t < port_off_t_size) {
	    /* should never happen */
	    G_fatal_error(_("Vector exceeds supported file size limit"));
	}
    }
    else {
	if (nat_off_t >= port_off_t_size) {
	    /* read into buffer */
	    buf_alloc(cnt * port_off_t_size);
	    ret = dig_fread(buffer, port_off_t_size, cnt, fp);
	    if (ret != (int) cnt)
		return 0;
	    /* set buffer to zero (positive numbers) */
	    memset(buf, 0, cnt * sizeof(off_t));
	    /* read from buffer in changed order */
	    c1 = (unsigned char *)buffer;
	    c2 = (unsigned char *)buf;
	    for (i = 0; i < cnt; i++) {
		/* set to FF if the value is negative */
		if (Cur_Head->byte_order == ENDIAN_LITTLE) {
		    if (c1[port_off_t_size - 1] & 0x80)
			memset(c2, 0xff, sizeof(off_t));
		}
		else {
		    if (c1[0] & 0x80)
			memset(c2, 0xff, sizeof(off_t));
		}
		for (j = 0; j < port_off_t_size; j++)
		    c2[Cur_Head->off_t_cnvrt[j]] = c1[j];
		c1 += port_off_t_size;
		c2 += sizeof(off_t);
	    }
	}
	else if (nat_off_t < port_off_t_size) {
	    /* should never happen */
	    G_fatal_error(_("Vector exceeds supported file size limit"));
	}
    }
    return 1;
}

/*!
  \brief Read longs from the Portable Vector Format

   These routines must handle any type size conversions between the
   portable format and the native machine.

   \param[out] buf data buffer
   \param cnt number of members
   \param fp pointer to struct gvfile

   \return 0 error
   \return 1 OK
*/
int dig__fread_port_L(long *buf, size_t cnt, struct gvfile * fp)
{
    unsigned int i, j;
    int ret;
    unsigned char *c1, *c2;

    if (Cur_Head->lng_quick) {
	if (nat_lng == PORT_LONG) {
	    ret = dig_fread(buf, PORT_LONG, cnt, fp);
	    if (ret != (int) cnt)
		return 0;
	}
	else {
	    /* read into buffer */
	    buf_alloc(cnt * PORT_LONG);
	    ret = dig_fread(buffer, PORT_LONG, cnt, fp);
	    if (ret != (int) cnt)
		return 0;
	    /* set buffer to zero (positive numbers) */
	    memset(buf, 0, cnt * sizeof(long));
	    /* read from buffer in changed order */
	    c1 = (unsigned char *)buffer;
	    c2 = (unsigned char *)buf;
	    for (i = 0; i < cnt; i++) {
		/* set to FF if the value is negative */
		if (lng_order == ENDIAN_LITTLE) {
		    if (c1[PORT_LONG - 1] & 0x80)
			memset(c2, 0xff, sizeof(long));
		    memcpy(c2, c1, PORT_LONG);
		}
		else {
		    if (c1[0] & 0x80)
			memset(c2, 0xff, sizeof(long));
		    memcpy(c2 + nat_lng - PORT_LONG, c1, PORT_LONG);
		}
		c1 += PORT_LONG;
		c2 += sizeof(long);
	    }
	}
    }
    else {
	/* read into buffer */
	buf_alloc(cnt * PORT_LONG);
	ret = dig_fread(buffer, PORT_LONG, cnt, fp);
	if (ret != (int) cnt)
	    return 0;
	/* set buffer to zero (positive numbers) */
	memset(buf, 0, cnt * sizeof(long));
	/* read from buffer in changed order */
	c1 = (unsigned char *)buffer;
	c2 = (unsigned char *)buf;
	for (i = 0; i < cnt; i++) {
	    /* set to FF if the value is negative */
	    if (Cur_Head->byte_order == ENDIAN_LITTLE) {
		if (c1[PORT_LONG - 1] & 0x80)
		    memset(c2, 0xff, sizeof(long));
	    }
	    else {
		if (c1[0] & 0x80)
		    memset(c2, 0xff, sizeof(long));
	    }
	    for (j = 0; j < PORT_LONG; j++)
		c2[Cur_Head->lng_cnvrt[j]] = c1[j];
	    c1 += PORT_LONG;
	    c2 += sizeof(long);
	}
    }
    return 1;
}

/*!
  \brief Read integers from the Portable Vector Format

   These routines must handle any type size conversions between the
   portable format and the native machine.

   \param[out] buf data buffer
   \param cnt number of members
   \param fp pointer to struct gvfile

   \return 0 error
   \return 1 OK
*/
int dig__fread_port_I(int *buf, size_t cnt, struct gvfile * fp)
{
    unsigned int i, j;
    int ret;
    unsigned char *c1, *c2;

    if (Cur_Head->int_quick) {
	if (nat_int == PORT_INT) {
	    ret = dig_fread(buf, PORT_INT, cnt, fp);
	    if (ret != (int) cnt)
		return 0;
	}
	else {
	    /* read into buffer */
	    buf_alloc(cnt * PORT_INT);
	    ret = dig_fread(buffer, PORT_INT, cnt, fp);
	    if (ret != (int) cnt)
		return 0;
	    /* set buffer to zero (positive numbers) */
	    memset(buf, 0, cnt * sizeof(int));
	    /* read from buffer in changed order */
	    c1 = (unsigned char *)buffer;
	    c2 = (unsigned char *)buf;
	    for (i = 0; i < cnt; i++) {
		/* set to FF if the value is negative */
		if (int_order == ENDIAN_LITTLE) {
		    if (c1[PORT_INT - 1] & 0x80)
			memset(c2, 0xff, sizeof(int));
		    memcpy(c2, c1, PORT_INT);
		}
		else {
		    if (c1[0] & 0x80)
			memset(c2, 0xff, sizeof(int));
		    memcpy(c2 + nat_int - PORT_INT, c1, PORT_INT);
		}
		c1 += PORT_INT;
		c2 += sizeof(int);
	    }
	}
    }
    else {
	/* read into buffer */
	buf_alloc(cnt * PORT_INT);
	ret = dig_fread(buffer, PORT_INT, cnt, fp);
	if (ret != (int) cnt)
	    return 0;
	/* set buffer to zero (positive numbers) */
	memset(buf, 0, cnt * sizeof(int));
	/* read from buffer in changed order */
	c1 = (unsigned char *)buffer;
	c2 = (unsigned char *)buf;
	for (i = 0; i < cnt; i++) {
	    /* set to FF if the value is negative */
	    if (Cur_Head->byte_order == ENDIAN_LITTLE) {
		if (c1[PORT_INT - 1] & 0x80)
		    memset(c2, 0xff, sizeof(int));
	    }
	    else {
		if (c1[0] & 0x80)
		    memset(c2, 0xff, sizeof(int));
	    }
	    for (j = 0; j < PORT_INT; j++)
		c2[Cur_Head->int_cnvrt[j]] = c1[j];
	    c1 += PORT_INT;
	    c2 += sizeof(int);
	}
    }
    return 1;
}

/*!
  \brief Read shorts from the Portable Vector Format

   These routines must handle any type size conversions between the
   portable format and the native machine.

   \param[out] buf data buffer
   \param cnt number of members
   \param fp pointer to struct gvfile

   \return 0 error
   \return 1 OK
*/
int dig__fread_port_S(short *buf, size_t cnt, struct gvfile * fp)
{
    unsigned int i, j;
    int ret;
    unsigned char *c1, *c2;

    if (Cur_Head->shrt_quick) {
	if (nat_shrt == PORT_SHORT) {
	    ret = dig_fread(buf, PORT_SHORT, cnt, fp);
	    if (ret != (int) cnt)
		return 0;
	}
	else {
	    /* read into buffer */
	    buf_alloc(cnt * PORT_SHORT);
	    if (0 >= (ret = dig_fread(buffer, PORT_SHORT, cnt, fp)))
		if (ret != (int) cnt)
		    return 0;
	    /* set buffer to zero (positive numbers) */
	    memset(buf, 0, cnt * sizeof(short));
	    /* read from buffer in changed order */
	    c1 = (unsigned char *)buffer;
	    c2 = (unsigned char *)buf;
	    for (i = 0; i < cnt; i++) {
		/* set to FF if the value is negative */
		if (shrt_order == ENDIAN_LITTLE) {
		    if (c1[PORT_SHORT - 1] & 0x80)
			memset(c2, 0xff, sizeof(short));
		    memcpy(c2, c1, PORT_SHORT);
		}
		else {
		    if (c1[0] & 0x80)
			memset(c2, 0xff, sizeof(short));
		    memcpy(c2 + nat_shrt - PORT_SHORT, c1, PORT_SHORT);
		}
		c1 += PORT_SHORT;
		c2 += sizeof(short);
	    }
	}
    }
    else {
	/* read into buffer */
	buf_alloc(cnt * PORT_SHORT);
	ret = dig_fread(buffer, PORT_SHORT, cnt, fp);
	if (ret != (int) cnt)
	    return 0;
	/* set buffer to zero (positive numbers) */
	memset(buf, 0, cnt * sizeof(short));
	/* read from buffer in changed order */
	c1 = (unsigned char *)buffer;
	c2 = (unsigned char *)buf;
	for (i = 0; i < cnt; i++) {
	    /* set to FF if the value is negative */
	    if (Cur_Head->byte_order == ENDIAN_LITTLE) {
		if (c1[PORT_SHORT - 1] & 0x80)
		    memset(c2, 0xff, sizeof(short));
	    }
	    else {
		if (c1[0] & 0x80)
		    memset(c2, 0xff, sizeof(short));
	    }
	    for (j = 0; j < PORT_SHORT; j++)
		c2[Cur_Head->shrt_cnvrt[j]] = c1[j];
	    c1 += PORT_SHORT;
	    c2 += sizeof(short);
	}
    }
    return 1;
}

/*!
  \brief Read chars from the Portable Vector Format

   These routines must handle any type size conversions between the
   portable format and the native machine.

   \param[out] buf data buffer
   \param cnt number of members
   \param fp pointer to gvfile structure

   \return 0 error
   \return 1 OK
*/
int dig__fread_port_C(char *buf, size_t cnt, struct gvfile * fp)
{
    int ret;

    ret = dig_fread(buf, PORT_CHAR, cnt, fp);
    if (ret != (int) cnt)
	return 0;
    return 1;
}

/*!
  \brief Read plus_t from the Portable Vector Format

   These routines must handle any type size conversions between the
   portable format and the native machine.
   
   plus_t is defined as int so we only retype pointer and use int
   function.

   \param[out] buf data buffer
   \param cnt number of members
   \param fp pointer to struct gvfile

   \return 0 error
   \return 1 OK
*/
int dig__fread_port_P(plus_t * buf, size_t cnt, struct gvfile * fp)
{
    int *ibuf;

    ibuf = (int *)buf;

    return (dig__fread_port_I(ibuf, cnt, fp));
}

/*!
  \brief Write doubles to the Portable Vector Format

   These routines must handle any type size conversions between the
   portable format and the native machine.

   \param buf data buffer
   \param cnt number of members
   \param[in,out] fp pointer to struct gvfile

   \return 0 error
   \return 1 OK
*/
int dig__fwrite_port_D(const double *buf,
		       size_t cnt, struct gvfile * fp)
{
    unsigned int i, j;
    unsigned char *c1, *c2;

    if (Cur_Head->dbl_quick) {
	if (dig_fwrite(buf, PORT_DOUBLE, cnt, fp) == cnt)
	    return 1;
    }
    else {
	buf_alloc(cnt * PORT_DOUBLE);
	c1 = (unsigned char *)buf;
	c2 = (unsigned char *)buffer;
	for (i = 0; i < cnt; i++) {
	    for (j = 0; j < PORT_DOUBLE; j++)
		c2[j] = c1[Cur_Head->dbl_cnvrt[j]];
	    c1 += sizeof(double);
	    c2 += PORT_DOUBLE;
	}
	if (dig_fwrite(buffer, PORT_DOUBLE, cnt, fp) == cnt)
	    return 1;
    }
    return 0;
}

/*!
  \brief Write floats to the Portable Vector Format

   These routines must handle any type size conversions between the
   portable format and the native machine.

   \param buf data buffer
   \param cnt number of members
   \param[in,out] fp pointer to struct gvfile

   \return 0 error
   \return 1 OK
*/
int dig__fwrite_port_F(const float *buf,
		       size_t cnt, struct gvfile * fp)
{
    unsigned int i, j;
    unsigned char *c1, *c2;

    if (Cur_Head->flt_quick) {
	if (dig_fwrite(buf, PORT_FLOAT, cnt, fp) == cnt)
	    return 1;
    }
    else {
	buf_alloc(cnt * PORT_FLOAT);
	c1 = (unsigned char *)buf;
	c2 = (unsigned char *)buffer;
	for (i = 0; i < cnt; i++) {
	    for (j = 0; j < PORT_FLOAT; j++)
		c2[j] = c1[Cur_Head->flt_cnvrt[j]];
	    c1 += sizeof(float);
	    c2 += PORT_FLOAT;
	}
	if (dig_fwrite(buffer, PORT_FLOAT, cnt, fp) == cnt)
	    return 1;
    }
    return 0;
}

/*!
  \brief Write off_ts to the Portable Vector Format

   These routines must handle any type size conversions between the
   portable format and the native machine.

   \param buf data buffer
   \param cnt number of members
   \param[in,out] fp pointer to struct gvfile
   \param port_off_t_size

   \return 0 error
   \return 1 OK
*/
int dig__fwrite_port_O(const off_t *buf,
		       size_t cnt, struct gvfile * fp, size_t port_off_t_size)
{
    unsigned int i, j;
    unsigned char *c1, *c2;

    if (Cur_Head->off_t_quick) {
	if (nat_off_t == port_off_t_size) {
	    if (dig_fwrite(buf, port_off_t_size, cnt, fp) == cnt)
		return 1;
	}
	else if (nat_off_t > port_off_t_size) {
	    buf_alloc(cnt * port_off_t_size);
	    c1 = (unsigned char *)buf;
	    c2 = (unsigned char *)buffer;
	    for (i = 0; i < cnt; i++) {
		if (off_t_order == ENDIAN_LITTLE)
		    memcpy(c2, c1, port_off_t_size);
		else
		    memcpy(c2, c1 + nat_off_t - port_off_t_size, port_off_t_size);
		c1 += sizeof(off_t);
		c2 += port_off_t_size;
	    }
	    if (dig_fwrite(buffer, port_off_t_size, cnt, fp) == cnt)
		return 1;
	}
	else if (nat_off_t < port_off_t_size) {
	    /* should never happen */
	    G_fatal_error("Vector exceeds supported file size limit");
	}
    }
    else {
	if (nat_off_t >= port_off_t_size) {
    	    buf_alloc(cnt * port_off_t_size);
	    c1 = (unsigned char *)buf;
	    c2 = (unsigned char *)buffer;
	    for (i = 0; i < cnt; i++) {
		for (j = 0; j < port_off_t_size; j++)
		    c2[j] = c1[Cur_Head->off_t_cnvrt[j]];
		c1 += sizeof(off_t);
		c2 += port_off_t_size;
	    }
	    if (dig_fwrite(buffer, port_off_t_size, cnt, fp) == cnt)
		return 1;
	}
	else if (nat_off_t < port_off_t_size) {
	    /* should never happen */
	    G_fatal_error(_("Vector exceeds supported file size limit"));
	}
    }
    return 0;
}

/*!
  \brief Write longs to the Portable Vector Format

   These routines must handle any type size conversions between the
   portable format and the native machine.

   \param buf data buffer
   \param cnt number of members
   \param[in,out] fp pointer to struct gvfile

   \return 0 error
   \return 1 OK
*/
int dig__fwrite_port_L(const long *buf,
		       size_t cnt, struct gvfile * fp)
{
    unsigned int i, j;
    unsigned char *c1, *c2;

    if (Cur_Head->lng_quick) {
	if (nat_lng == PORT_LONG) {
	    if (dig_fwrite(buf, PORT_LONG, cnt, fp) == cnt)
		return 1;
	}
	else {
	    buf_alloc(cnt * PORT_LONG);
	    c1 = (unsigned char *)buf;
	    c2 = (unsigned char *)buffer;
	    for (i = 0; i < cnt; i++) {
		if (lng_order == ENDIAN_LITTLE)
		    memcpy(c2, c1, PORT_LONG);
		else
		    memcpy(c2, c1 + nat_lng - PORT_LONG, PORT_LONG);
		c1 += sizeof(long);
		c2 += PORT_LONG;
	    }
	    if (dig_fwrite(buffer, PORT_LONG, cnt, fp) == cnt)
		return 1;
	}
    }
    else {
	buf_alloc(cnt * PORT_LONG);
	c1 = (unsigned char *)buf;
	c2 = (unsigned char *)buffer;
	for (i = 0; i < cnt; i++) {
	    for (j = 0; j < PORT_LONG; j++)
		c2[j] = c1[Cur_Head->lng_cnvrt[j]];
	    c1 += sizeof(long);
	    c2 += PORT_LONG;
	}
	if (dig_fwrite(buffer, PORT_LONG, cnt, fp) == cnt)
	    return 1;
    }
    return 0;
}

/*!
  \brief Write integers to the Portable Vector Format

   These routines must handle any type size conversions between the
   portable format and the native machine.

   \param buf data buffer
   \param cnt number of members
   \param[in,out] fp pointer to struct gvfile

   \return 0 error
   \return 1 OK
*/
int dig__fwrite_port_I(const int *buf,
		       size_t cnt, struct gvfile * fp)
{
    unsigned int i, j;
    unsigned char *c1, *c2;

    if (Cur_Head->int_quick) {
	if (nat_int == PORT_INT) {
	    if (dig_fwrite(buf, PORT_INT, cnt, fp) == cnt)
		return 1;
	}
	else {
	    buf_alloc(cnt * PORT_INT);
	    c1 = (unsigned char *)buf;
	    c2 = (unsigned char *)buffer;
	    for (i = 0; i < cnt; i++) {
		if (int_order == ENDIAN_LITTLE)
		    memcpy(c2, c1, PORT_INT);
		else
		    memcpy(c2, c1 + nat_int - PORT_INT, PORT_INT);
		c1 += sizeof(int);
		c2 += PORT_INT;
	    }
	    if (dig_fwrite(buffer, PORT_INT, cnt, fp) == cnt)
		return 1;
	}
    }
    else {
	buf_alloc(cnt * PORT_INT);
	c1 = (unsigned char *)buf;
	c2 = (unsigned char *)buffer;
	for (i = 0; i < cnt; i++) {
	    for (j = 0; j < PORT_INT; j++)
		c2[j] = c1[Cur_Head->int_cnvrt[j]];
	    c1 += sizeof(int);
	    c2 += PORT_INT;
	}
	if (dig_fwrite(buffer, PORT_INT, cnt, fp) == cnt)
	    return 1;
    }
    return 0;
}

/*!
  \brief Write shorts to the Portable Vector Format

   These routines must handle any type size conversions between the
   portable format and the native machine.

   \param buf data buffer
   \param cnt number of members
   \param[in,out] fp pointer to struct gvfile

   \return 0 error
   \return 1 OK
*/
int dig__fwrite_port_S(const short *buf,
		       size_t cnt, struct gvfile * fp)
{
    unsigned int i, j;
    unsigned char *c1, *c2;

    if (Cur_Head->shrt_quick) {
	if (nat_shrt == PORT_SHORT) {
	    if (dig_fwrite(buf, PORT_SHORT, cnt, fp) == cnt)
		return 1;
	}
	else {
	    buf_alloc(cnt * PORT_SHORT);
	    c1 = (unsigned char *)buf;
	    c2 = (unsigned char *)buffer;
	    for (i = 0; i < cnt; i++) {
		if (shrt_order == ENDIAN_LITTLE)
		    memcpy(c2, c1, PORT_SHORT);
		else
		    memcpy(c2, c1 + nat_shrt - PORT_SHORT, PORT_SHORT);
		c1 += sizeof(short);
		c2 += PORT_SHORT;
	    }
	    if (dig_fwrite(buffer, PORT_SHORT, cnt, fp) == cnt)
		return 1;
	}
    }
    else {
	buf_alloc(cnt * PORT_SHORT);
	c1 = (unsigned char *)buf;
	c2 = (unsigned char *)buffer;
	for (i = 0; i < cnt; i++) {
	    for (j = 0; j < PORT_SHORT; j++)
		c2[j] = c1[Cur_Head->shrt_cnvrt[j]];
	    c1 += sizeof(short);
	    c2 += PORT_SHORT;
	}
	if (dig_fwrite(buffer, PORT_SHORT, cnt, fp) == cnt)
	    return 1;
    }
    return 0;
}


/*!
  \brief Write plus_t to the Portable Vector Format

   These routines must handle any type size conversions between the
   portable format and the native machine.

   \param buf data buffer
   \param cnt number of members
   \param[in,out] fp pointer to struct gvfile

   \return 0 error
   \return 1 OK
*/
int dig__fwrite_port_P(const plus_t * buf,
		       size_t cnt, struct gvfile * fp)
{
    return (dig__fwrite_port_I((int *)buf, cnt, fp));
}

/*!
  \brief Write chars to the Portable Vector Format

   These routines must handle any type size conversions between the
   portable format and the native machine.

   \param buf data buffer
   \param cnt number of members
   \param[in,out] fp pointer to struct gvfile

   \return 0 error
   \return 1 OK
*/
int dig__fwrite_port_C(const char *buf,
		       size_t cnt, struct gvfile * fp)
{
    if (dig_fwrite(buf, PORT_CHAR, cnt, fp) == cnt)
	return 1;

    return 0;
}

/*!
  \brief Set Port_info structure to byte order of file

  \param port pointer to Port_info structure
  \param byte_order ENDIAN_BIG or ENDIAN_LITTLE
*/
void dig_init_portable(struct Port_info *port, int byte_order)
{
    unsigned int i;

    port_init();

    port->byte_order = byte_order;

    /* double */
    if (port->byte_order == dbl_order)
	port->dbl_quick = TRUE;
    else
	port->dbl_quick = FALSE;

    for (i = 0; i < PORT_DOUBLE; i++) {
	if (port->byte_order == ENDIAN_BIG)
	    port->dbl_cnvrt[i] = dbl_cnvrt[i];
	else
	    port->dbl_cnvrt[i] = dbl_cnvrt[PORT_DOUBLE - i - 1];
    }

    /* float */
    if (port->byte_order == flt_order)
	port->flt_quick = TRUE;
    else
	port->flt_quick = FALSE;

    for (i = 0; i < PORT_FLOAT; i++) {
	if (port->byte_order == ENDIAN_BIG)
	    port->flt_cnvrt[i] = flt_cnvrt[i];
	else
	    port->flt_cnvrt[i] = flt_cnvrt[PORT_FLOAT - i - 1];
    }

    /* long */
    if (port->byte_order == lng_order)
	port->lng_quick = TRUE;
    else
	port->lng_quick = FALSE;

    for (i = 0; i < PORT_LONG; i++) {
	if (port->byte_order == ENDIAN_BIG)
	    port->lng_cnvrt[i] = lng_cnvrt[i];
	else
	    port->lng_cnvrt[i] = lng_cnvrt[PORT_LONG - i - 1];
    }

    /* int */
    if (port->byte_order == int_order)
	port->int_quick = TRUE;
    else
	port->int_quick = FALSE;

    for (i = 0; i < PORT_INT; i++) {
	if (port->byte_order == ENDIAN_BIG)
	    port->int_cnvrt[i] = int_cnvrt[i];
	else
	    port->int_cnvrt[i] = int_cnvrt[PORT_INT - i - 1];
    }

    /* short */
    if (port->byte_order == shrt_order)
	port->shrt_quick = TRUE;
    else
	port->shrt_quick = FALSE;

    for (i = 0; i < PORT_SHORT; i++) {
	if (port->byte_order == ENDIAN_BIG)
	    port->shrt_cnvrt[i] = shrt_cnvrt[i];
	else
	    port->shrt_cnvrt[i] = shrt_cnvrt[PORT_SHORT - i - 1];
    }

    /* off_t */
    if (port->byte_order == off_t_order)
	port->off_t_quick = TRUE;
    else
	port->off_t_quick = FALSE;

    for (i = 0; i < nat_off_t; i++) {
	if (port->byte_order == ENDIAN_BIG)
	    port->off_t_cnvrt[i] = off_t_cnvrt[i];
	else
	    port->off_t_cnvrt[i] = off_t_cnvrt[nat_off_t - i - 1];
    }

    return;
}

/*!
  \brief Set current Port_info structure

  \param port pointer to Port_info structure

  \return 0
*/
int dig_set_cur_port(struct Port_info *port)
{
    Cur_Head = port;
    return 0;
}

/*!
  \brief Get byte order

  \return ENDIAN_LITTLE
  \return ENDIAN_BIG
*/
int dig__byte_order_out()
{
    if (dbl_order == ENDIAN_LITTLE)
	return (ENDIAN_LITTLE);
    else
	return (ENDIAN_BIG);
}