plctrl.c

/* $Id: plctrl.c 10418 2009-09-17 01:56:26Z airwin $

    Misc. control routines, like begin, end, exit, change graphics/text
    mode, change color.  Includes some spillage from plcore.c.  If you
    don't know where it should go, put it here.

   Copyright (C) 2004  Joao Cardoso
   Copyright (C) 2004  Rafael Laboissiere
   Copyright (C) 2008  Hazen Babcock
   Copyright (C) 2009  Alan W. Irwin

   This file is part of PLplot.

   PLplot is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Library Public License as published
   by the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   PLplot 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 PLplot; if not, write to the Free Software
   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

*/

#define DEBUG

#define NEED_PLDEBUG
#include "plplotP.h"
#ifdef macintosh
#include "mac.h"
/* for plMacLibOpen prototype; used in plLibOpen */
#endif

#ifdef DJGPP            /* dos386/djgpp */
#ifdef __unix
#undef __unix
#endif
#endif

#ifdef __unix
#include <sys/types.h>
#include <sys/stat.h>
#ifdef PL_HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <errno.h>
#endif

/* Random number generator (Mersenne Twister) */
#include "mt19937ar.h"

#define BUFFER_SIZE 256

/* small epsilon for fuzzy range checks that is still large enough to
   work even in the single precision floating point case.*/
#define FUZZ_EPSILON 1.e-4

/* Static functions */

/* Used by any external init code to suggest a path */
char PLDLLIMPEXP * plplotLibDir = 0;

static void
color_set(PLINT i, U_CHAR r, U_CHAR g, U_CHAR b, PLFLT a, char *name );

static void
strcat_delim(char *dirspec);

static int
(*exit_handler) (const char *errormsg);

static void
(*abort_handler) (const char *errormsg);

static void
plcmap0_def(int imin, int imax);

static void
plcmap1_def(void);

static PLFLT
value(double n1, double n2, double hue);

static void
cmap0_palette_read(const char *filename,
                   int *number_colors, int **r, int **g, int **b, double **a);
/* An additional hardwired location for lib files. */
/* I have no plans to change these again, ever. */

#if defined(DJGPP)
#ifndef PLLIBDEV
#define PLLIBDEV "c:/plplot/lib"
#endif

#elif defined(MSDOS)
#ifndef PLLIBDEV
#define PLLIBDEV "c:\\plplot\\lib"
#endif

#else

/* Anything else is assumed to be Unix */

#ifndef PLLIBDEV
#define PLLIBDEV "/usr/local/plplot/lib"
#endif

#endif

/*--------------------------------------------------------------------------*\
 *  Routines that deal with colors & color maps.
\*--------------------------------------------------------------------------*/

/*--------------------------------------------------------------------------*\
 * plcol0()
 *
 * Set color, map 0.  Argument is integer between 0 and plsc->ncol0.
\*--------------------------------------------------------------------------*/

void
c_plcol0(PLINT icol0)
{
    if (plsc->level < 1) {
    plabort("plcol0: Please call plinit first");
    return;
    }
    if (icol0 < 0 || icol0 >= plsc->ncol0) {
    char buffer[BUFFER_SIZE];
    snprintf(buffer, BUFFER_SIZE, "plcol0: Invalid color map entry: %d", (int) icol0);
    plabort(buffer);
    return;
    }

    plsc->icol0 = icol0;
    plsc->curcolor.r = plsc->cmap0[icol0].r;
    plsc->curcolor.g = plsc->cmap0[icol0].g;
    plsc->curcolor.b = plsc->cmap0[icol0].b;
    plsc->curcolor.a = plsc->cmap0[icol0].a;

    plsc->curcmap = 0;
    plP_state(PLSTATE_COLOR0);
}

/*--------------------------------------------------------------------------*\
 * plcol1()
 *
 * Set color, map 1.  Argument is a float between 0. and 1.
\*--------------------------------------------------------------------------*/

void
c_plcol1(PLFLT col1)
{
    PLINT icol1;

    if (plsc->level < 1) {
    plabort("plcol1: Please call plinit first");
    return;
    }
    if (col1 < 0 || col1 > 1) {
    char buffer[BUFFER_SIZE];
    snprintf(buffer, BUFFER_SIZE, "plcol1: Invalid color map position: %f", (PLFLT) col1);
    plabort(buffer);
    return;
    }

    icol1 = (PLINT)(col1 * plsc->ncol1);
    icol1 = MIN(icol1, plsc->ncol1-1);

    plsc->icol1 = icol1;
    plsc->curcolor.r = plsc->cmap1[plsc->icol1].r;
    plsc->curcolor.g = plsc->cmap1[plsc->icol1].g;
    plsc->curcolor.b = plsc->cmap1[plsc->icol1].b;
    plsc->curcolor.a = plsc->cmap1[plsc->icol1].a;

    plsc->curcmap = 1;
    plP_state(PLSTATE_COLOR1);
}

/*--------------------------------------------------------------------------*\
 * plscolbg()
 *
 * Set the background color (cmap0[0]) by 8 bit RGB value
\*--------------------------------------------------------------------------*/

void
c_plscolbg(PLINT r, PLINT g, PLINT b)
{
    plscol0(0, r, g, b);
}

/*--------------------------------------------------------------------------*\
 * plscolbga()
 *
 * Set the background color (cmap0[0]) by 8 bit RGB value and alpha value
\*--------------------------------------------------------------------------*/

void
c_plscolbga(PLINT r, PLINT g, PLINT b, PLFLT a)
{
  plscol0a(0, r, g, b, a);
}

/*--------------------------------------------------------------------------*\
 * plgcolbg()
 *
 * Returns the background color (cmap0[0]) by 8 bit RGB value
\*--------------------------------------------------------------------------*/

void
c_plgcolbg(PLINT *r, PLINT *g, PLINT *b)
{
    plgcol0(0, r, g, b);
}

/*--------------------------------------------------------------------------*\
 * plgcolbga()
 *
 * Returns the background color (cmap0[0]) by 8 bit RGB value and alpha value
\*--------------------------------------------------------------------------*/

void
c_plgcolbga(PLINT *r, PLINT *g, PLINT *b, PLFLT *a)
{
  plgcol0a(0, r, g, b, a);
}

/*--------------------------------------------------------------------------*\
 * plscol0()
 *
 * Set a given color from color map 0 by 8 bit RGB value
 * Does not result in any additional cells to be allocated.
\*--------------------------------------------------------------------------*/

void
c_plscol0(PLINT icol0, PLINT r, PLINT g, PLINT b)
{
    if (plsc->cmap0 == NULL)
    plscmap0n(0);
    if (icol0 < 0 || icol0 >= plsc->ncol0) {
    char buffer[BUFFER_SIZE];
    snprintf(buffer, BUFFER_SIZE, "plscol0: Illegal color table value: %d", (int) icol0);
    plabort(buffer);
    return;
    }
    if ((r < 0 || r > 255) || (g < 0 || g > 255) || (b < 0 || b > 255)) {
    char buffer[BUFFER_SIZE];
    snprintf(buffer, BUFFER_SIZE, "plscol0: Invalid RGB color: %d, %d, %d",
        (int) r, (int) g, (int) b);
    plabort(buffer);
    return;
    }

    plscol0a(icol0, r, g, b, 1.0);
}

/*--------------------------------------------------------------------------*\
 * plscol0a()
 *
 * Set a given color from color map 0 by 8 bit RGB value and alpha value.
 * Does not result in any additional cells to be allocated.
\*--------------------------------------------------------------------------*/

void
c_plscol0a(PLINT icol0, PLINT r, PLINT g, PLINT b, PLFLT a)
{
    if (plsc->cmap0 == NULL)
    plscmap0n(0);
    if (icol0 < 0 || icol0 >= plsc->ncol0) {
    char buffer[BUFFER_SIZE];
    snprintf(buffer, BUFFER_SIZE, "plscol0a: Illegal color table value: %d", (int) icol0);
    plabort(buffer);
    return;
    }
    if ((r < 0 || r > 255) || (g < 0 || g > 255) || (b < 0 || b > 255) || (a < 0 || a > 1.0)) {
    char buffer[BUFFER_SIZE];
    snprintf(buffer, BUFFER_SIZE, "plscol0a: Invalid RGB color: %d, %d, %d, %f",
        (int) r, (int) g, (int) b, (double) a);
    plabort(buffer);
    return;
    }

    plsc->cmap0[icol0].r = r;
    plsc->cmap0[icol0].g = g;
    plsc->cmap0[icol0].b = b;
    plsc->cmap0[icol0].a = a;

    if (plsc->level > 0)
    plP_state(PLSTATE_CMAP0);
}

/*--------------------------------------------------------------------------*\
 * plgcol0()
 *
 * Returns 8 bit RGB values for given color from color map 0
 * Values are negative if an invalid color id is given
\*--------------------------------------------------------------------------*/

void
c_plgcol0(PLINT icol0, PLINT *r, PLINT *g, PLINT *b)
{
    if (plsc->cmap0 == NULL)
    plscmap0n(0);

    *r = -1;
    *g = -1;
    *b = -1;

    if (icol0 < 0 || icol0 > plsc->ncol0) {
    char buffer[BUFFER_SIZE];
    snprintf(buffer, BUFFER_SIZE, "plgcol0: Invalid color index: %d", (int) icol0);
    plabort(buffer);
    return;
    }

    *r = plsc->cmap0[icol0].r;
    *g = plsc->cmap0[icol0].g;
    *b = plsc->cmap0[icol0].b;

    return;
}

/*--------------------------------------------------------------------------*\
 * plgcol0a()
 *
 * Returns 8 bit RGB values for given color from color map 0 and alpha value
 * Values are negative if an invalid color id is given
\*--------------------------------------------------------------------------*/

void
c_plgcol0a(PLINT icol0, PLINT *r, PLINT *g, PLINT *b, PLFLT *a)
{
    if (plsc->cmap0 == NULL)
    plscmap0n(0);

    *r = -1;
    *g = -1;
    *b = -1;
    *a = -1.0;

    if (icol0 < 0 || icol0 > plsc->ncol0) {
    char buffer[BUFFER_SIZE];
    snprintf(buffer, BUFFER_SIZE, "plgcol0: Invalid color index: %d", (int) icol0);
    plabort(buffer);
    return;
    }

    *r = plsc->cmap0[icol0].r;
    *g = plsc->cmap0[icol0].g;
    *b = plsc->cmap0[icol0].b;
    *a = plsc->cmap0[icol0].a;

    return;
}

/*--------------------------------------------------------------------------*\
 * plscmap0()
 *
 * Set color map 0 colors by 8 bit RGB values.  This sets the entire color
 * map -- only as many colors as specified will be allocated.
\*--------------------------------------------------------------------------*/

void
c_plscmap0(PLINT *r, PLINT *g, PLINT *b, PLINT ncol0)
{
    int i;

    plscmap0n(ncol0);

    for (i = 0; i < plsc->ncol0; i++) {
    if ((r[i] < 0 || r[i] > 255) ||
        (g[i] < 0 || g[i] > 255) ||
        (b[i] < 0 || b[i] > 255)) {

        char buffer[BUFFER_SIZE];
        snprintf(buffer, BUFFER_SIZE, "plscmap0: Invalid RGB color: %d, %d, %d",
            (int) r[i], (int) g[i], (int) b[i]);
        plabort(buffer);
        return;
    }

    plsc->cmap0[i].r = r[i];
    plsc->cmap0[i].g = g[i];
    plsc->cmap0[i].b = b[i];
    plsc->cmap0[i].a = 1.0;
    }

    if (plsc->level > 0)
    plP_state(PLSTATE_CMAP0);
}

/*--------------------------------------------------------------------------*\
 * plscmap0a()
 *
 * Set color map 0 colors by 8 bit RGB and alpha value.  This sets the 
 * entire color map -- only as many colors as specified will be allocated.
\*--------------------------------------------------------------------------*/

void
c_plscmap0a(PLINT *r, PLINT *g, PLINT *b, PLFLT *a, PLINT ncol0)
{
    int i;

    plscmap0n(ncol0);

    for (i = 0; i < plsc->ncol0; i++) {
    if ((r[i] < 0 || r[i] > 255) ||
        (g[i] < 0 || g[i] > 255) ||
        (b[i] < 0 || b[i] > 255) ||
        (a[i] < 0.0 || a[i] > 1.0)) {

        char buffer[BUFFER_SIZE];
        snprintf(buffer, BUFFER_SIZE, "plscmap0a: Invalid RGB color: %d, %d, %d, %f",
            (int) r[i], (int) g[i], (int) b[i], (double) a[i]);
        plabort(buffer);
        return;
    }

    plsc->cmap0[i].r = r[i];
    plsc->cmap0[i].g = g[i];
    plsc->cmap0[i].b = b[i];
    plsc->cmap0[i].a = a[i];
    }

    if (plsc->level > 0)
    plP_state(PLSTATE_CMAP0);
}

/*--------------------------------------------------------------------------*\
 * plscmap1()
 *
 * Set color map 1 colors by 8 bit RGB values
 * This also sets the number of colors.
\*--------------------------------------------------------------------------*/

void
c_plscmap1(PLINT *r, PLINT *g, PLINT *b, PLINT ncol1)
{
    int i;

    plscmap1n(ncol1);

    for (i = 0; i < plsc->ncol1; i++) {
    if ((r[i] < 0 || r[i] > 255) ||
        (g[i] < 0 || g[i] > 255) ||
        (b[i] < 0 || b[i] > 255)) {

        char buffer[BUFFER_SIZE];
        snprintf(buffer, BUFFER_SIZE, "plscmap1: Invalid RGB color: %d, %d, %d",
            (int) r[i], (int) g[i], (int) b[i]);
        plabort(buffer);
        return;
    }
    plsc->cmap1[i].r = r[i];
    plsc->cmap1[i].g = g[i];
    plsc->cmap1[i].b = b[i];
    plsc->cmap1[i].a = 1.0;
    }

    if (plsc->level > 0)
    plP_state(PLSTATE_CMAP1);
}

/*--------------------------------------------------------------------------*\
 * plscmap1a()
 *
 * Set color map 1 colors by 8 bit RGB and alpha values
 * This also sets the number of colors.
\*--------------------------------------------------------------------------*/

void
c_plscmap1a(PLINT *r, PLINT *g, PLINT *b, PLFLT *a, PLINT ncol1)
{
    int i;

    plscmap1n(ncol1);

    for (i = 0; i < plsc->ncol1; i++) {
    if ((r[i] < 0 || r[i] > 255) ||
        (g[i] < 0 || g[i] > 255) ||
        (b[i] < 0 || b[i] > 255) ||
        (a[i] < 0.0 || a[i] > 1.0)) {

        char buffer[BUFFER_SIZE];
        snprintf(buffer, BUFFER_SIZE, "plscmap1a: Invalid RGB color: %d, %d, %d, %f",
            (int) r[i], (int) g[i], (int) b[i], (double) a[i]);
        plabort(buffer);
        return;
    }
    plsc->cmap1[i].r = r[i];
    plsc->cmap1[i].g = g[i];
    plsc->cmap1[i].b = b[i];
    plsc->cmap1[i].a = a[i];
    }

    if (plsc->level > 0)
    plP_state(PLSTATE_CMAP1);
}

/*--------------------------------------------------------------------------*\
 * plscmap1l()
 *
 * Set color map 1 colors using a piece-wise linear relationship between
 * position in the color map (from 0 to 1) and position in HLS or RGB color
 * space.  May be called at any time.
 *
 * The idea here is to specify a number of control points that specify the
 * mapping between HLS (or RGB or CMY) and palette 1 value.  Between these
 * points, linear interpolation is used.  By mapping position in the color
 * map to function value, this gives a smooth variation of color with
 * intensity.  Any number of control points may be specified, located at
 * arbitrary positions (intensities), although typically 2 - 4 are enough.
 * Another way of stating this is that we are traversing a given number of
 * lines through HLS (or RGB) space as we move through cmap 1 entries.  The
 * control points at the minimum and maximum intensity (0 and 1) must
 * always be specified.  By adding more control points you can get more
 * variation.  One good technique for plotting functions that vary about
 * some expected average is to use an additional 2 control points in the
 * center (intensity ~= 0.5) that are the same color as the background
 * (typically white for paper output, black for crt), and same hue as the
 * boundary control points.  This allows the highs and lows to be very
 * easily distinguished.
 *
 * Each control point must specify the position in cmap 1 as well as three
 * coordinates in HLS or RGB space.  The first point MUST correspond to
 * position = 0, and the last to position = 1.
 *
 * The hue is interpolated around the "front" of the color wheel
 * (red<->green<->blue<->red) unless the "rev" flag is set, in which case
 * interpolation proceeds around the back (reverse) side.  Specifying
 * rev=NULL is equivalent to setting rev[]=0 for every control point.
 *
 * Bounds on RGB coordinates:
 *  R,G,B       [0, 1]      magnitude
 *
 * Bounds on HLS coordinates:
 *  hue     [0, 360]    degrees
 *  lightness   [0, 1]      magnitude
 *  saturation  [0, 1]      magnitude
 *
 * The inputs are:
 *  itype       0: HLS, 1: RGB
 *  npts        number of control points
 *  pos[]       position for each control point
 *  coord1[]    first coordinate for each control point
 *  coord2[]    second coordinate for each control point
 *  coord3[]    third coordinate for each control point
 *  rev[]       reverse flag for each control point
\*--------------------------------------------------------------------------*/

void
c_plscmap1l(PLINT itype, PLINT npts, PLFLT *pos,
        PLFLT *coord1, PLFLT *coord2, PLFLT *coord3, PLINT *rev)
{
    int n;
    PLFLT h, l, s, r, g, b;

    if (npts < 2) {
    plabort("plscmap1l: Must specify at least two control points");
    return;
    }

    if ( (pos[0] != 0) || (pos[npts-1] != 1)) {
    plabort("plscmap1l: First, last control points must lie on boundary");
    return;
    }

    if ( npts > PL_MAX_CMAP1CP ) {
    plabort("plscmap1l: exceeded maximum number of control points");
    return;
    }

/* Allocate if not done yet */

    if (plsc->cmap1 == NULL)
    plscmap1n(0);

/* Save control points */

    plsc->ncp1 = npts;

    for (n = 0; n < npts; n++) {

    if (itype == 0) {
        h = coord1[n];
        l = coord2[n];
        s = coord3[n];
    }
    else {
        r = coord1[n];
        g = coord2[n];
        b = coord3[n];
        c_plrgbhls(r, g, b, &h, &l, &s);
    }

    plsc->cmap1cp[n].h = h;
    plsc->cmap1cp[n].l = l;
    plsc->cmap1cp[n].s = s;
    plsc->cmap1cp[n].p = pos[n];
    plsc->cmap1cp[n].a = 1.0;

    if (rev == NULL)
        plsc->cmap1cp[n].rev = 0;
    else
        plsc->cmap1cp[n].rev = rev[n];
    }

/* Calculate and set color map */

    plcmap1_calc();
}

/*--------------------------------------------------------------------------*\
 * plscmap1la()
 *
 * This is the same as plscmap1l, but also allows alpha value interpolation.
 *
 \*-------------------------------------------------------------------------*/

void
c_plscmap1la(PLINT itype, PLINT npts, PLFLT *pos,
         PLFLT *coord1, PLFLT *coord2, PLFLT *coord3, PLFLT *a, PLINT *rev)
{
    int n;
    PLFLT h, l, s, r, g, b;

    if (npts < 2) {
    plabort("plscmap1la: Must specify at least two control points");
    return;
    }

    if ( (pos[0] != 0) || (pos[npts-1] != 1)) {
    plabort("plscmap1la: First, last control points must lie on boundary");
    return;
    }

    if ( npts > PL_MAX_CMAP1CP ) {
    plabort("plscmap1la: exceeded maximum number of control points");
    return;
    }

/* Allocate if not done yet */

    if (plsc->cmap1 == NULL)
    plscmap1n(0);

/* Save control points */

    plsc->ncp1 = npts;

    for (n = 0; n < npts; n++) {

    if (itype == 0) {
        h = coord1[n];
        l = coord2[n];
        s = coord3[n];
    }
    else {
        r = coord1[n];
        g = coord2[n];
        b = coord3[n];
        c_plrgbhls(r, g, b, &h, &l, &s);
    }

    plsc->cmap1cp[n].h = h;
    plsc->cmap1cp[n].l = l;
    plsc->cmap1cp[n].s = s;
    plsc->cmap1cp[n].p = pos[n];
    plsc->cmap1cp[n].a = a[n];

    if (rev == NULL)
        plsc->cmap1cp[n].rev = 0;
    else
        plsc->cmap1cp[n].rev = rev[n];
    }

/* Calculate and set color map */

    plcmap1_calc();
}

/*--------------------------------------------------------------------------*\
 * plcmap1_calc()
 *
 * Bin up cmap 1 space and assign colors to make inverse mapping easy.
 * Always do interpolation in HLS space.
\*--------------------------------------------------------------------------*/

void
plcmap1_calc(void)
{
    int i, n;
    PLFLT delta, dp, dh, dl, ds, da;
    PLFLT h, l, s, p, r, g, b, a;

/* Loop over all control point pairs */

    for (n = 0; n < plsc->ncp1-1; n++) {

    if ( plsc->cmap1cp[n].p == plsc->cmap1cp[n+1].p )
        continue;

    /* Differences in p, h, l, s between ctrl pts */

    dp = plsc->cmap1cp[n+1].p - plsc->cmap1cp[n].p;
    dh = plsc->cmap1cp[n+1].h - plsc->cmap1cp[n].h;
    dl = plsc->cmap1cp[n+1].l - plsc->cmap1cp[n].l;
    ds = plsc->cmap1cp[n+1].s - plsc->cmap1cp[n].s;
    da = plsc->cmap1cp[n+1].a - plsc->cmap1cp[n].a;

    /* Adjust dh if we are to go around "the back side" */

    if (plsc->cmap1cp[n].rev)
        dh = (dh > 0) ? dh-360 : dh+360;

    /* Loop over all color cells.  Only interested in cells located (in */
    /* cmap1 space)  between n_th and n+1_th control points */

    for (i = 0; i < plsc->ncol1; i++) {
        p = (double) i / (plsc->ncol1 - 1.0);
        if ( (p < plsc->cmap1cp[n].p) ||
         (p > plsc->cmap1cp[n+1].p) )
        continue;

    /* Interpolate based on position of color cell in cmap1 space */

        delta = (p - plsc->cmap1cp[n].p) / dp;

    /* Linearly interpolate to get color cell h, l, s values */

        h = plsc->cmap1cp[n].h + dh * delta;
        l = plsc->cmap1cp[n].l + dl * delta;
        s = plsc->cmap1cp[n].s + ds * delta;
        a = plsc->cmap1cp[n].a + da * delta;

        while (h >= 360.)
        h -= 360.;

        while (h < 0.)
        h += 360.;

        c_plhlsrgb(h, l, s, &r, &g, &b);

        plsc->cmap1[i].r = MAX(0, MIN(255, (int) (256. * r)));
        plsc->cmap1[i].g = MAX(0, MIN(255, (int) (256. * g)));
        plsc->cmap1[i].b = MAX(0, MIN(255, (int) (256. * b)));
        plsc->cmap1[i].a = a;
    }
    }

    if (plsc->level > 0)
    plP_state(PLSTATE_CMAP1);
}

/*--------------------------------------------------------------------------*\
 * plscmap0n()
 *
 * Set number of colors in cmap 0, (re-)allocate cmap 0, and fill with
 * default values for those colors not previously allocated (and less
 * than index 15, after that you just get grey).
 *
 * The driver is not guaranteed to support all of these.
\*--------------------------------------------------------------------------*/

void
c_plscmap0n(PLINT ncol0)
{
    int ncol, size, imin, imax;

/* No change */

    if (ncol0 > 0 && plsc->ncol0 == ncol0)
    return;

/* Handle all possible startup conditions */

    if (plsc->ncol0 <= 0 && ncol0 <= 0)
    ncol = 16;
    else if (ncol0 <= 0)
    ncol = plsc->ncol0;
    else
        ncol = ncol0;

    imax = ncol-1;
    size = ncol * sizeof(PLColor);

/* Allocate the space */

    if (plsc->cmap0 == NULL) {
      if ((plsc->cmap0 = (PLColor *) calloc(1, size))==NULL)
     {
       plexit("c_plscmap0n: Insufficient memory");
     }
    imin = 0;
    }
    else {
    if ((plsc->cmap0 = (PLColor *) realloc(plsc->cmap0, size))==NULL)
     {
       plexit("c_plscmap0n: Insufficient memory");
     }
    imin = plsc->ncol0;
    }

/* Fill in default entries */

    plsc->ncol0 = ncol;
    plcmap0_def(imin, imax);

    if (plsc->level > 0)
    plP_state(PLSTATE_CMAP0);
}

/*--------------------------------------------------------------------------*\
 * color_set()
 *
 * Initializes color table entry by RGB values.
\*--------------------------------------------------------------------------*/

void
color_set(PLINT i, U_CHAR r, U_CHAR g, U_CHAR b, PLFLT a, char *name )
{
    plsc->cmap0[i].r = r;
    plsc->cmap0[i].g = g;
    plsc->cmap0[i].b = b;
    plsc->cmap0[i].a = a;
    plsc->cmap0[i].name = name;
}

#define color_def(i, r, g, b, a, n)         \
  if (i >= imin && i <= imax) color_set(i, r, g, b, a, n);

/*--------------------------------------------------------------------------*\
 * plcmap0_def()
 *
 * Initializes specified color map 0 color entry to its default for
 * index range from imin to imax.
\*--------------------------------------------------------------------------*/

void
plcmap0_def(int imin, int imax)
{
  int i, *r, *g, *b;
  double *a;
  int number_colors;
  if(imin <= imax) {
    cmap0_palette_read("", &number_colors, &r, &g, &b, &a);
    for (i = imin; i <= MIN((number_colors-1),imax); i++)
      color_def(i, r[i], g[i], b[i], a[i],
              "colors defined by default cmap0 palette file");
    free(r);
    free(g);
    free(b);
    free(a);
    
  } else {
    number_colors = 0;
  }

  /* Initialize all colours undefined by the default colour palette file
     to opaque red as a warning. */
  for (i = MAX(number_colors, imin); i <= imax; i++)
    color_def(i, 255, 0, 0, 1.0,
              "opaque red colour to mark not defined by palette file");
}

/*--------------------------------------------------------------------------*\
 * plscmap1n()
 *
 * Set number of colors in cmap 1, (re-)allocate cmap 1, and set default
 * values if this is the first allocation.
 *
 * Note that the driver is allowed to disregard this number.
 * In particular, most use fewer than we use internally.
\*--------------------------------------------------------------------------*/

void
c_plscmap1n(PLINT ncol1)
{
    int ncol, size;

/* No change */

    if (ncol1 > 0 && plsc->ncol1 == ncol1)
    return;

/* Handle all possible startup conditions */

    if (plsc->ncol1 <= 0 && ncol1 <= 0)
    ncol = 128;
    else if (ncol1 <= 0)
    ncol = plsc->ncol1;
    else
        ncol = ncol1;

    size = ncol * sizeof(PLColor);

/* Allocate the space */

    if (plsc->ncol1 > 0)
      {
        if ((plsc->cmap1 = (PLColor *) realloc(plsc->cmap1, size))==NULL)
          {
            plexit("c_plscmap1n: Insufficient memory");
          }
      }
    else
      {
        if ((plsc->cmap1 = (PLColor *) calloc(ncol, sizeof(PLColor)))==NULL)
          {
            plexit("c_plscmap1n: Insufficient memory");
          }
      }

/* Fill in default entries */

    plsc->ncol1 = ncol;
    if (plsc->ncp1 == 0)
    plcmap1_def();
    else
    plcmap1_calc();
}

/*--------------------------------------------------------------------------*\
 * plcmap1_def()
 *
 * Initializes color map 1.
 *
 * The default initialization uses 6 control points in HLS space, the inner
 * ones being very close to one of the vertices of the HLS double cone.  The
 * vertex used (black or white) is chosen to be the closer to the background
 * color.  The 6 points were chosen over the older 4 points in order to make
 * weaker structures more easily visible, and give more control through the
 * palette editor.  If you don't like these settings.. change them!
\*--------------------------------------------------------------------------*/

void
plcmap1_def(void)
{
    PLFLT i[6], h[6], l[6], s[6], midpt = 0., vertex = 0.;

/* Positions of control points */

    i[0] = 0;       /* left boundary */
    i[1] = 0.44;    /* a little left of center */
    i[2] = 0.50;    /* at center */
    i[3] = 0.50;    /* at center */
    i[4] = 0.56;    /* a little right of center */
    i[5] = 1;       /* right boundary */

/* For center control points, pick black or white, whichever is closer to bg */
/* Be careful to pick just short of top or bottom else hue info is lost */

    if (plsc->cmap0 != NULL)
    vertex = ((PLFLT) plsc->cmap0[0].r +
          (PLFLT) plsc->cmap0[0].g +
          (PLFLT) plsc->cmap0[0].b) / 3. / 255.;

    if (vertex < 0.5) {
    vertex = 0.01;
    midpt  = 0.10;
    } else {
    vertex = 0.99;
    midpt  = 0.90;
    }

/* Set hue */

    h[0] = 260;     /* low: blue-violet */
    h[1] = 260;     /* only change as we go over vertex */
    h[2] = 260;     /* only change as we go over vertex */
    h[3] = 0;       /* high: red */
    h[4] = 0;       /* high: red */
    h[5] = 0;       /* keep fixed */

/* Set lightness */

    l[0] = 0.5;     /* low */
    l[1] = midpt;   /* midpoint value */
    l[2] = vertex;  /* bg */
    l[3] = vertex;  /* bg */
    l[4] = midpt;   /* midpoint value */
    l[5] = 0.5;     /* high */

/* Set saturation -- keep at maximum */

    s[0] = 1;
    s[1] = 1;
    s[2] = 1;
    s[3] = 1;
    s[4] = 1;
    s[5] = 1;

    c_plscmap1l(0, 6, i, h, l, s, NULL);

    if (plsc->level > 0)
    plP_state(PLSTATE_CMAP1);
}

/*--------------------------------------------------------------------------*\
 * plscolor()
 *
 * Used to globally turn color output on/off
\*--------------------------------------------------------------------------*/

void
c_plscolor(PLINT color)
{
    plsc->colorset = 1;
    plsc->color = color;
}

/*--------------------------------------------------------------------------*\
 * plrgb()
 *
 * Set line color by red, green, blue from  0. to 1.
 * Do NOT use this.  Only retained for backward compatibility
\*--------------------------------------------------------------------------*/

void
c_plrgb(PLFLT r, PLFLT g, PLFLT b)
{
    if (plsc->level < 1) {
    plabort("plrgb: Please call plinit first");
    return;
    }

    plsc->icol0 = PL_RGB_COLOR;
    plsc->curcolor.r = MAX(0, MIN(255, (int) (256. * r)));
    plsc->curcolor.g = MAX(0, MIN(255, (int) (256. * g)));
    plsc->curcolor.b = MAX(0, MIN(255, (int) (256. * b)));

    plsc->curcmap = 0;
    plP_state(PLSTATE_COLOR0);
}

/*--------------------------------------------------------------------------*\
 * plrgb1()
 *
 * Set line color by 8 bit RGB values.
 * Do NOT use this.  Only retained for backward compatibility
\*--------------------------------------------------------------------------*/

void
c_plrgb1(PLINT r, PLINT g, PLINT b)
{
    if (plsc->level < 1) {
    plabort("plrgb1: Please call plinit first");
    return;
    }
    if ((r < 0 || r > 255) || (g < 0 || g > 255) || (b < 0 || b > 255)) {
    plabort("plrgb1: Invalid color");
    return;
    }

    plsc->icol0 = PL_RGB_COLOR;
    plsc->curcolor.r = r;
    plsc->curcolor.g = g;
    plsc->curcolor.b = b;

    plsc->curcmap = 0;
    plP_state(PLSTATE_COLOR0);
}

/*--------------------------------------------------------------------------*\
 * void plhls()
 *
 * Set current color by hue, lightness, and saturation.
 * Convert hls color coordinates to rgb, then call plrgb.
 * Do NOT use this.  Only retained for backward compatibility
\*--------------------------------------------------------------------------*/

void
c_plhls(PLFLT h, PLFLT l, PLFLT s)
{
    PLFLT r, g, b;

    c_plhlsrgb(h, l, s, &r, &g, &b);
    plrgb(r, g, b);
}

/*--------------------------------------------------------------------------*\
 * void value()
 *
 * Auxiliary function used by c_plhlsrgb().
\*--------------------------------------------------------------------------*/

PLFLT
value(double n1, double n2, double hue)
{
    PLFLT val;

    while (hue >= 360.)
    hue -= 360.;
    while (hue < 0.)
    hue += 360.;

    if (hue < 60.)
    val = n1 + (n2 - n1) * hue / 60.;
    else if (hue < 180.)
    val = n2;
    else if (hue < 240.)
    val = n1 + (n2 - n1) * (240. - hue) / 60.;
    else
    val = n1;

    return (val);
}

/*--------------------------------------------------------------------------*\
 * void c_plhlsrgb()
 *
 * Convert HLS color to RGB color.
 * Bounds on HLS (input):
 *  hue     [0., 360.]  degrees
 *  lightness   [0., 1.]    magnitude
 *  saturation  [0., 1.]    magnitude
 *
 * Hue is always mapped onto the interval [0., 360.] regardless of input.
 * Bounds on RGB (output) is always [0., 1.].  Convert to RGB color values
 * by multiplying by 2**nbits (nbits typically 8).
\*--------------------------------------------------------------------------*/

void
c_plhlsrgb(PLFLT h, PLFLT l, PLFLT s, PLFLT *p_r, PLFLT *p_g, PLFLT *p_b)
{
    PLFLT m1, m2;

    if (l <= .5)
    m2 = l * (s + 1.);
    else
    m2 = l + s - l * s;

    m1 = 2 * l - m2;

    *p_r = value(m1, m2, h + 120.);
    *p_g = value(m1, m2, h);
    *p_b = value(m1, m2, h - 120.);
}

/*--------------------------------------------------------------------------*\
 * void c_plrgbhls()
 *
 * Convert RGB color to HLS color.
 * Bounds on RGB (input) is always [0., 1.].
 * Bounds on HLS (output):
 *  hue     [0., 360.]  degrees
 *  lightness   [0., 1.]    magnitude
 *  saturation  [0., 1.]    magnitude
\*--------------------------------------------------------------------------*/

void
c_plrgbhls(PLFLT r, PLFLT g, PLFLT b, PLFLT *p_h, PLFLT *p_l, PLFLT *p_s)
{
    PLFLT h, l, s, d, rc, gc, bc, rgb_min, rgb_max;

    rgb_min = MIN( r, MIN( g, b ));
    rgb_max = MAX( r, MAX( g, b ));

    l = (rgb_min+rgb_max) / 2.0;

    if (rgb_min == rgb_max) {
    s = 0;
    h = 0;
    }
    else {
    d = rgb_max - rgb_min;
    if (l < 0.5)
        s = 0.5 * d / l;
    else
        s = 0.5* d / (1.-l);

    rc = (rgb_max-r) / d;
    gc = (rgb_max-g) / d;
    bc = (rgb_max-b) / d;

    if (r == rgb_max)
        h = bc-gc;
    else if (g == rgb_max)
        h = rc-bc+2;
    else
        h = gc-rc-2;

    h = h*60;
    if (h <  0)
        h = h+360;
    else if (h >= 360)
        h = h-360;
    }
    *p_h = h;
    *p_l = l;
    *p_s = s;
}

/*--------------------------------------------------------------------------*\
 * cmap0_palette_read()
 *
 * Read and check r, g, b, a data from a cmap0*.pal format file.
 * The caller must free the returned malloc'ed space for r, g, b, and a.
\*--------------------------------------------------------------------------*/

void
cmap0_palette_read(const char *filename,
                   int *number_colors, int **r, int **g, int **b, double **a)
{
  int i, err = 0;
  char color_info[30];
  char msgbuf[1024];
  FILE *fp;
  char * save_locale = plsave_set_locale();

  if(strlen(filename) == 0) {
    fp = plLibOpen(PL_DEFAULT_CMAP0_FILE);
    if (fp == NULL) {
      snprintf(msgbuf,1024,"Unable to open cmap0 file %s\n",PL_DEFAULT_CMAP0_FILE);
      plwarn(msgbuf);
      err = 1;
    }
  } else {
    fp = plLibOpen(filename);
    if (fp == NULL) {
      snprintf(msgbuf,1024,"Unable to open cmap0 file %s\n",filename);
      plwarn(msgbuf);
      err = 1;
    }
  }
  if (!err &&(fscanf(fp, "%d\n", number_colors) != 1 || *number_colors < 1)) {
    fclose(fp);
    snprintf(msgbuf,1024,"Unrecognized cmap0 header\n");
    plwarn(msgbuf);
    err = 1;
  }

  if(!err) {
    /* Allocate arrays to hold r, g, b, and a data for calling routine.
       The caller must free these after it is finished with them. */
    if(((*r = (int *)malloc(*number_colors * sizeof(int))) == NULL) ||
       ((*g = (int *)malloc(*number_colors * sizeof(int))) == NULL) ||
       ((*b = (int *)malloc(*number_colors * sizeof(int))) == NULL) ||
       ((*a = (double *)malloc(*number_colors * sizeof(double))) == NULL)) {
      fclose(fp);
      plexit("cmap0_palette_read: insufficient memory");
    }
          
    for(i=0;i<*number_colors;i++){
      fgets(color_info, 30, fp);
      color_info[strlen(color_info)-1] = '\0'; /* remove return character */
      if(strlen(color_info) == 7){
        if (sscanf(color_info, "#%2x%2x%2x",
                   (int *) (*r+i), (int *) (*g+i), (int *) (*b+i)) != 3) {
          err = 1;
          break;
        }
        *(*a+i) = 1.0;
      } else if(strlen(color_info) > 9) {
        if (sscanf(color_info, "#%2x%2x%2x %lf",
                   (int *) (*r+i), (int *) (*g+i), (int *) (*b+i),
                   (double *) (*a+i)) != 4) {
          err = 1;
          break;
        }
        /* fuzzy range check. */
        if(*(*a+i) < -FUZZ_EPSILON || *(*a+i) > (1. + FUZZ_EPSILON)) {
          err = 1;
          break;
        } else if(*(*a+i) < 0.) {
          *(*a+i) = 0.;
        } else if(*(*a+i) > 1.) {
          *(*a+i) = 1.;
        }
      } else {
        err = 1;
        break;
      }
    }
    fclose(fp);
    if(err) {
      snprintf(msgbuf,1024,"Unrecognized cmap0 format data line.  Line is %s\n",
               color_info);
      plwarn(msgbuf);
      free(*r);
      free(*g);
      free(*b);
      free(*a);
    }
  }
  /* Fall back to opaque red on opaque white as visual warning of any
     error above. */
  if(err) {
    *number_colors = 16;
    if(((*r = (int *)malloc(*number_colors * sizeof(int))) == NULL) ||
       ((*g = (int *)malloc(*number_colors * sizeof(int))) == NULL) ||
       ((*b = (int *)malloc(*number_colors * sizeof(int))) == NULL) ||
       ((*a = (double *)malloc(*number_colors * sizeof(double))) == NULL)) {
      plexit("cmap0_palette_read: insufficient memory");
    }
    **r = 255;
    **g = 255;
    **b = 255;
    **a = 1.;
    for(i=1;i<*number_colors;i++){
        *(*r+i) = 255;
        *(*g+i) = 0;
        *(*b+i) = 0;
        *(*a+i) = 1.0;
    }
  }

  plrestore_locale(save_locale);
}

/*--------------------------------------------------------------------------*\
 * void c_plspal0(filename)
 *
 * Set the palette for color map 0 using a cmap0*.pal format file.
 * filename: the name of the cmap0*.pal file to use.
\*--------------------------------------------------------------------------*/

void
c_plspal0(const char *filename)
{
  int i, *r, *g, *b;
  double *a;
  int number_colors;
  cmap0_palette_read(filename, &number_colors, &r, &g, &b, &a);
  /* Allocate default number of cmap0 colours if cmap0 allocation not
     done already. */
  plscmap0n(0);
  /* Allocate sufficient cmap0 colours to contain present data. */
  if(number_colors > plsc->ncol0) {
    plscmap0n(number_colors);
  }
  for(i=0;i<number_colors;i++){
    c_plscol0a(i, r[i], g[i], b[i], a[i]);
  }
  free(r);
  free(g);
  free(b);
  free(a);
}

/* This code fragment used a lot in plspal1 to deal with
   floating-point range checking of a value and the adjustment of that
   value when close to the range when there is floating-point errors.
*/
#define fuzzy_range_check(value, min, max, fuzz, err_number)            \
  if(value < (min - fuzz) || value > (max + fuzz)) {                    \
    snprintf(msgbuf,1024,"Unrecognized cmap1 format data line.  Error number is %d. Line is %s\n", err_number, color_info);                                   \
    plwarn(msgbuf);                                                     \
    err = 1;                                                            \
    break;                                                              \
  } else if (value < min) {                                             \
    value = min;                                                        \
  } else if (value > max) {                                             \
    value = max;                                                        \
  }
/*--------------------------------------------------------------------------*\
 * void c_plspal1(filename)
 *
 * Set the palette for color map 1 using a cmap1*.pal format file.
 * filename: the name of the cmap1*.pal file to use.
\*--------------------------------------------------------------------------*/

void
c_plspal1(const char *filename, PLBOOL interpolate)
{
  int i;
  int number_colors;
  int format_version, err;
  PLBOOL rgb;
  char color_info[160];
  int r_i, g_i, b_i, pos_i, rev_i;
  double r_d, g_d, b_d, a_d, pos_d;
  PLFLT *r, *g, *b, *a, *pos;
  PLINT *ri, *gi, *bi;
  PLBOOL *rev;
  FILE *fp;
  char msgbuf[1024];
  char * save_locale = plsave_set_locale();

  rgb = TRUE;
  err = 0;
  format_version = 0;
  if(strlen(filename) == 0) {
    fp = plLibOpen(PL_DEFAULT_CMAP1_FILE);
    if (fp == NULL) {
      snprintf(msgbuf,1024,"Unable to open cmap1 .pal file %s\n",PL_DEFAULT_CMAP1_FILE);
      plwarn(msgbuf);
      goto finish;
    }
  } else {
    fp = plLibOpen(filename);
    if (fp == NULL) {
      snprintf(msgbuf,1024,"Unable to open cmap1 .pal file %s\n",filename);
      plwarn(msgbuf);
      goto finish;
    }
  }
  /* Check for new file format */
  fgets(color_info, 160, fp);
  if (strncmp(color_info,"v2 ",2) == 0) {
    format_version = 1;
    if (strncmp(&color_info[3],"hls",3) == 0)
      rgb = FALSE;
    else if (strncmp(&color_info[3],"rgb",3) == 0)
      rgb = TRUE;
    else {
      snprintf(msgbuf,1024,"Invalid color space %s - assuming RGB\n",&color_info[3]);
      plwarn(msgbuf);
      rgb = TRUE;
    }
    fgets(color_info, 160, fp);
  }

  if (sscanf(color_info, "%d\n", &number_colors) != 1 || number_colors < 2) {
    snprintf(msgbuf,1024,"Unrecognized cmap1 format (wrong number of colors) %s\n", color_info);
    plwarn(msgbuf);
    fclose(fp);
    goto finish;
  }

  r = (PLFLT *)malloc(number_colors * sizeof(PLFLT));
  g = (PLFLT *)malloc(number_colors * sizeof(PLFLT));
  b = (PLFLT *)malloc(number_colors * sizeof(PLFLT));
  ri = (PLINT *)malloc(number_colors * sizeof(PLINT));
  gi = (PLINT *)malloc(number_colors * sizeof(PLINT));
  bi = (PLINT *)malloc(number_colors * sizeof(PLINT));
  a = (PLFLT *)malloc(number_colors * sizeof(PLFLT));
  pos = (PLFLT *)malloc(number_colors * sizeof(PLFLT));
  rev = (PLBOOL *)malloc(number_colors * sizeof(PLBOOL));

  if (format_version == 0) {
    int return_sscanf, return_sscanf_old=0;
    /* Old tk file format */
    for(i=0;i<number_colors;i++){
      fgets(color_info, 160, fp);
      /* Ensure string is null terminated if > 160 characters */
      color_info[159] = '\0';
      return_sscanf = sscanf(color_info, "#%2x%2x%2x %d %d", &r_i, &g_i, &b_i, &pos_i, &rev_i);
      if(return_sscanf < 4 || (return_sscanf_old != 0 && return_sscanf != return_sscanf_old)) {
    snprintf(msgbuf,1024,"Unrecognized cmap1 format (wrong number of items for version 1 of format) %s\n", color_info);
    plwarn(msgbuf);
    err = 1;
    break;
      }
      return_sscanf_old = return_sscanf;
      /* For old format, input colours range from 0 to 255 and
         need to be renormalized to the range from 0. to 1.. */
      r[i] = (PLFLT)r_i/255.;
      g[i] = (PLFLT)g_i/255.;
      b[i] = (PLFLT)b_i/255.;
      a[i] = 1.0;
      pos[i] = 0.01*(PLFLT)pos_i;
      fuzzy_range_check(r[i], 0., 1., FUZZ_EPSILON, 1);
      fuzzy_range_check(g[i], 0., 1., FUZZ_EPSILON, 2);
      fuzzy_range_check(b[i], 0., 1., FUZZ_EPSILON, 3);
      fuzzy_range_check(pos[i], 0., 1., FUZZ_EPSILON, 4);
      if(return_sscanf == 5) {
        /* Next to oldest tk format with rev specified. */
        rev[i] = (PLBOOL)rev_i;
      }
    }
    if(return_sscanf == 4) {
      /* Oldest tk format.  No rev specified. */
      free(rev);
      rev = NULL;
    }
  }
  else {
    /* New floating point file version with support for alpha and rev values */
    for(i=0;i<number_colors;i++){
      fgets(color_info, 160, fp);
      if (sscanf(color_info, "%lf %lf %lf %lf %lf %d", &pos_d, &r_d, &g_d, &b_d, &a_d, &rev_i) != 6) {
    snprintf(msgbuf,1024,"Unrecognized cmap1 format (wrong number of items for version 2 of format) %s\n", color_info);
    plwarn(msgbuf);
    err = 1;
    break;
      }
             
      r[i] = (PLFLT)r_d;
      g[i] = (PLFLT)g_d;
      b[i] = (PLFLT)b_d;
      a[i] = (PLFLT)a_d;
      pos[i] = (PLFLT)pos_d;
      /* Check that all rgba and pos data within range from 0. to
         1. except for the hls colour space case where the first
         coordinate is checked within range from 0. to 360.*/
      if(rgb) {
        fuzzy_range_check(r[i], 0., 1., FUZZ_EPSILON, 5);
      } else {
        fuzzy_range_check(r[i], 0., 360., (360.*FUZZ_EPSILON), 6);
      }
      fuzzy_range_check(g[i], 0., 1., FUZZ_EPSILON, 7);
      fuzzy_range_check(b[i], 0., 1., FUZZ_EPSILON, 8);
      fuzzy_range_check(a[i], 0., 1., FUZZ_EPSILON, 9);
      fuzzy_range_check(pos[i], 0., 1., FUZZ_EPSILON, 10);
      
      rev[i] = (PLBOOL)rev_i;
    }
  }
  fclose(fp);

  if (!err) {
    if (interpolate) {
        c_plscmap1la(rgb, number_colors, pos, r, g, b, a, rev);
    }
    else {
        for (i = 0; i < number_colors; i++) {
            ri[i] = r[i] * 255.0;
            gi[i] = g[i] * 255.0;
            bi[i] = b[i] * 255.0;
        }
        c_plscmap1a(ri, gi, bi, a, number_colors);
    }
  } else {
    /* Fall back to red scale as visual warning if some problem occurred
       above. */
    free(r);
    free(g);
    free(b);
    free(pos);
    number_colors = 2;
    r = (PLFLT *)malloc(number_colors * sizeof(PLFLT));
    g = (PLFLT *)malloc(number_colors * sizeof(PLFLT));
    b = (PLFLT *)malloc(number_colors * sizeof(PLFLT));
    pos = (PLFLT *)malloc(number_colors * sizeof(PLFLT));
    r[0] = 0.;
    r[1] = 1.;
    g[0] = 0.;
    g[1] = 0.;
    b[0] = 0.;
    b[1] = 0.;
    pos[0] = 0.;
    pos[1] = 1.;
    c_plscmap1l(TRUE, number_colors, pos, r, g, b, NULL);
  }

  free(r);
  free(g);
  free(b);
  free(ri);
  free(gi);
  free(bi);
  free(a);
  free(pos);
  free(rev);

finish: plrestore_locale(save_locale);
}

/*--------------------------------------------------------------------------*\
 * A grab-bag of various control routines.
\*--------------------------------------------------------------------------*/

/*--------------------------------------------------------------------------*\
 * void plwarn()
 *
 * A handy way to issue warnings, if need be.
\*--------------------------------------------------------------------------*/

void
plwarn(const char *errormsg)
{
    int was_gfx = 0;

    if (plsc->graphx == 1) {
    was_gfx = 1;
    pltext();
    }

    fprintf(stderr, "\n*** PLPLOT WARNING ***\n");
    if (*errormsg != '\0')
    fprintf(stderr, "%s\n", errormsg);

    if (was_gfx == 1)
    plgra();
}

/*--------------------------------------------------------------------------*\
 * void plabort()
 *
 * Much the same as plwarn(), but appends ", aborting operation" to the
 * error message.  Helps to keep source code uncluttered and provides a
 * convention for error aborts.
 *
 * If cleanup needs to be done in the main program, the user should write
 * his/her own exit handler and pass it in via plsabort().
\*--------------------------------------------------------------------------*/

void
plabort(const char *errormsg)
{

    if (abort_handler != NULL)
         (*abort_handler)(errormsg);

    if (plsc->errcode != NULL)
    *(plsc->errcode) = 1;

    if (plsc->errmsg != NULL) {
    sprintf(plsc->errmsg, "\n*** PLPLOT ERROR, ABORTING OPERATION ***\n");
    if (*errormsg != '\0')
        sprintf(plsc->errmsg, "%s, aborting operation\n", errormsg);

    } else {
    int was_gfx = 0;

    if (plsc->graphx == 1) {
        was_gfx = 1;
        pltext();
    }

    fprintf(stderr, "\n*** PLPLOT ERROR, ABORTING OPERATION ***\n");
    if (*errormsg != '\0')
        fprintf(stderr, "%s, aborting operation\n", errormsg);

    if (was_gfx == 1)
        plgra();
    }
}


/*--------------------------------------------------------------------------*\
 * void plsabort()
 *
 * Sets an optional user abort handler.
\*--------------------------------------------------------------------------*/

void
plsabort(void (*handler) (const char *))
{
    abort_handler = handler;
}

/*--------------------------------------------------------------------------*\
 * void plexit()
 *
 * In case of an abort this routine is called.  It just prints out an error
 * message and tries to clean up as much as possible.  It's best to turn
 * off pause and then restore previous setting before returning.
 *
 * If cleanup needs to be done in the main program, the user should write
 * his/her own exit handler and pass it in via plsexit().  This function
 * should should either call plend() before exiting, or simply return.
\*--------------------------------------------------------------------------*/

void
plexit(const char *errormsg)
{
    int status = 1;

    if (exit_handler != NULL)
    status = (*exit_handler)(errormsg);

    plsc->nopause = 1;
    if (*errormsg != '\0') {
    fprintf(stderr, "\n*** PLPLOT ERROR, IMMEDIATE EXIT ***\n");
    fprintf(stderr, "%s\n", errormsg);
    }
    plend();

    fprintf(stderr, "Program aborted\n");
    exit(status);
}

/*--------------------------------------------------------------------------*\
 * void plsexit()
 *
 * Sets an optional user exit handler.
\*--------------------------------------------------------------------------*/

void
plsexit(int (*handler) (const char *))
{
    exit_handler = handler;
}

/*--------------------------------------------------------------------------*\
 * void plgra()
 *
 * Switches to graphics screen.
 *
 * Here and in pltext() it's a good idea to return silently if plinit()
 * hasn't yet been called, since plwarn() calls pltext() and plgra(), and
 * plwarn() may be called at any time.
\*--------------------------------------------------------------------------*/

void
c_plgra(void)
{
    if (plsc->level > 0)
    plP_esc(PLESC_GRAPH, NULL);
}

void
c_plxormod(PLINT mode, PLINT *status)   /* xor mode */
{
  static int ostate = 0;

  if (!plsc->dev_xor) {
    *status = 0;
    return;
  }

  if (plsc->level > 0) {
    plP_esc(PLESC_XORMOD, &mode);
    if (mode) {
      ostate = plsc->plbuf_write;
      plsc->plbuf_write = 0;
    } else
      plsc->plbuf_write = ostate;
  }
  *status = 1;
}

/*--------------------------------------------------------------------------*\
 * void pltext()
 *
 * Switches to text screen.
\*--------------------------------------------------------------------------*/

void
c_pltext(void)
{
    if (plsc->level > 0)
    plP_esc(PLESC_TEXT, NULL);
}

/*--------------------------------------------------------------------------*\
 * void pl_cmd()
 *
 * Front-end to driver escape function.
 * In principle this can be used to pass just about anything directly
 * to the driver.
\*--------------------------------------------------------------------------*/

void
pl_cmd(PLINT op, void *ptr)
{
    plP_esc(op, ptr);
}

/*--------------------------------------------------------------------------*\
 * char *plFindCommand
 *
 * Looks for the specified executable file.  Search path:
 *      if command invoked in the build tree:
 *         build_tree/tk (plserver lies there - needed for the tk driver)
 *         build_tree/scripts (plpr lies there - needed for the tk driver)
 *      else
 *  PLPLOT_BIN_ENV = $(PLPLOT_BIN)
 *  current directory
 *  PLPLOT_HOME_ENV/bin = $(PLPLOT_HOME)/bin
 *  BIN_DIR
 *
 * The caller must free the returned pointer (points to malloc'ed memory)
 * when finished with it.
\*--------------------------------------------------------------------------*/

char *
plFindCommand(const char *fn)
{
    char *fs = NULL, *dn;

    /**** see if in build tree ***/
    if (plInBuildTree() == 1) {
        plGetName(BUILD_DIR, "bindings/tk", fn, &fs);
        if ( ! plFindName(fs))
            return fs;
    else {
      plGetName(BUILD_DIR, "scripts", fn, &fs);
      if ( ! plFindName(fs))
            return fs;
    }
    }

/* PLPLOT_BIN_ENV = $(PLPLOT_BIN) */

#if defined(PLPLOT_BIN_ENV)
    if ((dn = getenv(PLPLOT_BIN_ENV)) != NULL) {
        plGetName(dn, "", fn, &fs);
        if ( ! plFindName(fs))
            return fs;
        fprintf(stderr, PLPLOT_BIN_ENV"=\"%s\"\n", dn); /* what IS set? */
    }
#endif  /* PLPLOT_BIN_ENV */

/* Current directory */

    plGetName(".", "", fn, &fs);
    if ( ! plFindName(fs))
    return fs;

/* PLPLOT_HOME_ENV/bin = $(PLPLOT_HOME)/bin */

#if defined(PLPLOT_HOME_ENV)
    if ((dn = getenv(PLPLOT_HOME_ENV)) != NULL) {
        plGetName(dn, "bin", fn, &fs);
        if ( ! plFindName(fs))
            return fs;
        fprintf(stderr, PLPLOT_HOME_ENV"=\"%s\"\n",dn); /* what IS set? */
    }
#endif  /* PLPLOT_HOME_ENV */

/* BIN_DIR */

#if defined (BIN_DIR)
    plGetName(BIN_DIR, "", fn, &fs);
    if ( ! plFindName(fs))
    return fs;
#endif

/* Crapped out */

    free_mem(fs);
    fprintf(stderr, "plFindCommand: cannot locate command: %s\n", fn);
#if defined (BIN_DIR)
    fprintf(stderr, "bin dir=\"" BIN_DIR "\"\n" );      /* what WAS set? */
#endif  /* BIN_DIR */
    return NULL;
}

/*--------------------------------------------------------------------------*\
 * FILE *plLibOpen(fn)
 *
 * Return file pointer to lib file.
 * Locations checked:
 *  PLPLOT_LIB_ENV = $(PLPLOT_LIB)
 *  current directory
 *  PLPLOT_HOME_ENV/lib = $(PLPLOT_HOME)/lib
 *  DATA_DIR
 *  PLLIBDEV
\*--------------------------------------------------------------------------*/

FILE *
plLibOpen(const char *fn)
{
    FILE *ret = NULL;

    PDFstrm *pdfs = plLibOpenPdfstrm(fn);
    if (pdfs == NULL) {
        return NULL;
    }
    if (pdfs->file != NULL) {
        ret = pdfs->file;
    pdfs->file = NULL;
    }
    pdf_close(pdfs);
    return ret;
}

PDFstrm *
plLibOpenPdfstrm(const char *fn)
{
    PDFstrm *file;
    char *fs = NULL, *dn = NULL;

/****   search build tree               ****/

    if (plInBuildTree() == 1) {
      plGetName(SOURCE_DIR, "data", fn, &fs);

      if ((file = pdf_fopen(fs, "rb")) != NULL)
        goto done;
    }

/****   search PLPLOT_LIB_ENV = $(PLPLOT_LIB)   ****/

#if defined(PLPLOT_LIB_ENV)
    if ((dn = getenv(PLPLOT_LIB_ENV)) != NULL) {
        plGetName(dn, "", fn, &fs);

        if ((file = pdf_fopen(fs, "rb")) != NULL)
            goto done;
        fprintf(stderr, PLPLOT_LIB_ENV"=\"%s\"\n", dn); /* what IS set? */
    }
#endif  /* PLPLOT_LIB_ENV */

/****   search current directory    ****/

    if ((file = pdf_fopen(fn, "rb")) != NULL){
      pldebug("plLibOpenPdfstr", "Found file %s in current directory.\n", fn);
      free_mem(fs);
      return (file);
    }

/****   search PLPLOT_HOME_ENV/lib = $(PLPLOT_HOME)/lib ****/

#if defined (PLPLOT_HOME_ENV)
    if ((dn = getenv(PLPLOT_HOME_ENV)) != NULL) {
        plGetName(dn, "lib", fn, &fs);

        if ((file = pdf_fopen(fs, "rb")) != NULL)
            goto done;
        fprintf(stderr, PLPLOT_HOME_ENV"=\"%s\"\n",dn); /* what IS set? */
    }
#endif  /* PLPLOT_HOME_ENV/lib */

/****   search installed location   ****/

#if defined (DATA_DIR)
    plGetName(DATA_DIR, "", fn, &fs);

    if ((file = pdf_fopen(fs, "rb")) != NULL)
        goto done;
#endif  /* DATA_DIR */

/****   search hardwired location   ****/

#ifdef PLLIBDEV
    plGetName(PLLIBDEV, "", fn, &fs);

    if ((file = pdf_fopen(fs, "rb")) != NULL)
    goto done;
#endif  /* PLLIBDEV */

#ifdef macintosh
    file = plMacLibOpen(fn);
    if (file != NULL)
        goto done;
#endif /* macintosh */

    if (plplotLibDir != NULL) {
    plGetName(plplotLibDir, "", fn, &fs);
    if ((file = pdf_fopen(fs, "rb")) != NULL)
        goto done;
    }

/****   not found, give up  ****/
    pldebug("plLibOpenPdfstr", "File %s not found.\n", fn);
    free_mem(fs);
    return NULL;

done:
    pldebug("plLibOpenPdfstr", "Found file %s\n", fs);
    free_mem(fs);
    return (file);
}

/*--------------------------------------------------------------------------*\
 * int plFindName
 *
 * Authors: Paul Dubois (LLNL), others?
 * This function is in the public domain.
 *
 * Given a pathname, determine if it is a symbolic link.  If so, continue
 * searching to the ultimate terminus - there may be more than one link.
 * Use the error value to determine when the terminus is reached, and to
 * determine if the pathname really exists.  Then stat it to determine
 * whether it's executable.  Return 0 for an executable, errno otherwise.
 * Note that 'p' _must_ have at least one '/' character - it does by
 * construction in this program.  The contents of the array pointed to by
 * 'p' are changed to the actual pathname if findname is successful.
 *
 * This function is only defined under Unix for now.
\*--------------------------------------------------------------------------*/

#ifdef __unix
int
plFindName(char *p)
{
    int n;
    char buf[PLPLOT_MAX_PATH], *cp;
    extern int errno;
    struct stat sbuf;

    pldebug("plFindName", "Trying to find %s\n", p);
    while ((n = readlink(p, buf, PLPLOT_MAX_PATH)) > 0) {
    pldebug("plFindName", "Readlink read %d chars at: %s\n", n, p);
    if (buf[0] == '/') {
    /* Link is an absolute path */

        strncpy(p, buf, n);
        p[n] = '\0';
        pldebug("plFindName", "Link is absolute: %s\n", p);
    }
    else {
    /* Link is relative to its directory; make it absolute */

        cp = 1 + strrchr(p, '/');
        strncpy(cp, buf, n);
        cp[n] = '\0';
        pldebug("plFindName",
            "Link is relative: %s\n\tTotal path:%s\n", cp, p);
    }
    }

/* This macro not defined on the NEC SX-3 */

#ifdef SX
#define S_ISREG(mode)   (mode & S_IFREG)
#endif

/* SGI machines return ENXIO instead of EINVAL Dubois 11/92 */

    if (errno == EINVAL || errno == ENXIO) {
    pldebug("plFindName", "%s may be the one...\n", p);
    if ((stat(p, &sbuf) == 0) && S_ISREG(sbuf.st_mode)) {
        pldebug("plFindName", "%s is a regular file\n", p);
        return (access(p, X_OK));
    }
    }
    pldebug("plFindName", "%s found but is not executable\n", p);
    return (errno ? errno : -1);
}

#else
int
plFindName(char *p)
{
    return 1;
}
#endif

/*--------------------------------------------------------------------------*\
 * void plGetName()
 *
 * Gets search name for file by concatenating the dir, subdir, and file
 * name, allocating memory as needed.  The appropriate delimiter is added
 * after the dir specification as necessary.  The caller is responsible
 * for freeing the malloc'ed memory.
\*--------------------------------------------------------------------------*/

void
plGetName(const char *dir, const char *subdir, const char *filename, char **filespec)
{
    int lfilespec;

/* Malloc space for filespec */

    free_mem(*filespec);
    lfilespec = strlen(dir) + strlen(subdir) + strlen(filename) + 10;
    if ((*filespec = (char *) malloc(lfilespec))==NULL)
      {
        plexit("plGetName: Insufficient memory");
      }

    strcpy(*filespec, dir);

    if (*subdir != '\0') {
    strcat_delim(*filespec);
    strcat(*filespec, subdir);
    }
    if (*filename != '\0') {
    strcat_delim(*filespec);
    strcat(*filespec, filename);
    }
    pldebug("plGetName", "Length of full pathname of file to be found is %d\n", lfilespec);
    pldebug("plGetName", "Full pathname of file to be found is %s\n", *filespec);
}

/*--------------------------------------------------------------------------*\
 * void strcat_delim()
 *
 * Append path name deliminator if necessary (does not add one if one's
 * there already, or if dealing with a colon-terminated device name).
\*--------------------------------------------------------------------------*/

void
strcat_delim(char *dirspec)
{
    int ldirspec = strlen(dirspec);
#if defined (MSDOS) || defined(WIN32)
    if (dirspec[ldirspec-1] != '\\')
    strcat(dirspec, "\\");
#elif defined (macintosh)
    if (dirspec[ldirspec-1] != ':')
        strcat(dirspec, ":");
#else           /* unix is the default */
    if (dirspec[ldirspec-1] != '/')
    strcat(dirspec, "/");
#endif
}

/*--------------------------------------------------------------------------*\
 * plcol_interp()
 *
 * Initializes device cmap 1 entry by interpolation from pls->cmap1
 * entries.  Returned PLColor is supposed to represent the i_th color
 * out of a total of ncol colors in the current color scheme.
\*--------------------------------------------------------------------------*/

void
plcol_interp(PLStream *pls, PLColor *newcolor, int i, int ncol)
{
    PLFLT x, delta;
    int il, ir;

    x = (double) (i * (pls->ncol1-1)) / (double) (ncol-1);
    il = (int)x;
    ir = il + 1;
    delta = x - il;

    if (ir > pls->ncol1 || il < 0)
    fprintf(stderr, "Invalid color\n");

    else if (ir == pls->ncol1 || (delta == 0.)) {
    newcolor->r = pls->cmap1[il].r;
    newcolor->g = pls->cmap1[il].g;
    newcolor->b = pls->cmap1[il].b;
    newcolor->a = pls->cmap1[il].a;
    }
    else {
    newcolor->r = (unsigned char)((1.-delta) * pls->cmap1[il].r + delta * pls->cmap1[ir].r);
    newcolor->g = (unsigned char)((1.-delta) * pls->cmap1[il].g + delta * pls->cmap1[ir].g);
    newcolor->b = (unsigned char)((1.-delta) * pls->cmap1[il].b + delta * pls->cmap1[ir].b);
    newcolor->a = (1.-delta) * pls->cmap1[il].a + delta * pls->cmap1[ir].a;
    }
}

/*--------------------------------------------------------------------------*\
 * plOpenFile()
 *
 * Opens file for output, prompting if not set.
 * Prints extra newline at end to make output look better in batch runs.
 * A file name of "-" indicates output to stdout.
\*--------------------------------------------------------------------------*/

#define MAX_NUM_TRIES   10
void
plOpenFile(PLStream *pls)
{
    int i = 0, count = 0;
    size_t len;
    char line[BUFFER_SIZE];

    while (pls->OutFile == NULL) {

/* Setting pls->FileName = NULL forces creation of a new family member */
/* You should also free the memory associated with it if you do this */

    if (pls->family && pls->BaseName != NULL)
        plP_getmember(pls);

/* Prompt if filename still not known */

    if (pls->FileName == NULL) {
        do {
        fprintf(stdout, "Enter graphics output file name: ");
        plio_fgets(line, sizeof(line), stdin);
        len = strlen(line);
        if (len)
            len--;
        line[len] = '\0';   /* strip new-line */
        count++;        /* count zero entries */
        } while (!len && count < MAX_NUM_TRIES);
        plP_sfnam(pls, line);
    }

/* If name is "-", send to stdout */

    if ( ! strcmp(pls->FileName, "-")) {
        pls->OutFile = stdout;
        pls->output_type = 1;
        break;
    }

/* Need this here again, for prompted family initialization */

    if (pls->family && pls->BaseName != NULL)
        plP_getmember(pls);

    if (i++ > 10)
        plexit("Too many tries.");

    if ((pls->OutFile = fopen(pls->FileName, "wb+")) == NULL)
        fprintf(stderr, "Can't open %s.\n", pls->FileName);
    else
        pldebug("plOpenFile", "Opened %s\n", pls->FileName);
    }
}

/*--------------------------------------------------------------------------*\
 * plP_getmember()
 *
 * Sets up next file member name (in pls->FileName), but does not open it.
\*--------------------------------------------------------------------------*/

void
plP_getmember(PLStream *pls)
{
    char tmp[BUFFER_SIZE];
    char prefix[BUFFER_SIZE];
    char* suffix;
    char num[BUFFER_SIZE];
    int maxlen;

    maxlen = strlen(pls->BaseName) + 10;
    if (pls->FileName == NULL)
      {
        if ((pls->FileName = (char *) malloc(maxlen))==NULL)
          {
            plexit("plP_getmember: Insufficient memory");
          }
      }

    suffix = strstr (pls->BaseName, "%n");

    snprintf(tmp, BUFFER_SIZE, "%%0%1ii", (int) pls->fflen);
    snprintf(num, BUFFER_SIZE, tmp, pls->member);

    if (suffix == NULL)
      snprintf (pls->FileName, maxlen, "%s.%s", pls->BaseName, num);
    else {
      strncpy (prefix, pls->BaseName, BUFFER_SIZE-1);
      prefix [(suffix - pls->BaseName<BUFFER_SIZE)?(suffix-pls->BaseName):BUFFER_SIZE-1] = '\0';
      snprintf (pls->FileName, maxlen, "%s%s%s", prefix, num, suffix + 2);
    }

}

/*--------------------------------------------------------------------------*\
 * plP_sfnam()
 *
 * Sets up file name (with "%n" removed if present) & family stem name.
 * Reserve some extra space (10 chars) to hold an optional member number.
\*--------------------------------------------------------------------------*/

void
plP_sfnam(PLStream *pls, const char *fnam)
{
    char prefix[BUFFER_SIZE];
    char* suffix;
    int maxlen;
    pls->OutFile = NULL;

    if (pls->FileName != NULL)
    free((void *) pls->FileName);

    maxlen = 10 + strlen(fnam);
    if ((pls->FileName = (char *) malloc(maxlen))==NULL)
      {
        plexit("plP_sfnam: Insufficient memory");
      }

    suffix = strstr (fnam, "%n");

    if (suffix == NULL) {
      strncpy(pls->FileName, fnam, maxlen-1);
      pls->FileName[maxlen-1] = '\0';
    }
    else {
      strncpy (prefix, fnam, BUFFER_SIZE-1);
      prefix [(suffix - fnam)<BUFFER_SIZE?(suffix-fnam):BUFFER_SIZE-1] = '\0';
      snprintf (pls->FileName, maxlen, "%s%s", prefix, suffix + 2);
    }

    if (pls->BaseName != NULL)
    free((void *) pls->BaseName);

    if ((pls->BaseName = (char *) malloc(maxlen))==NULL)
      {
        plexit("plP_sfnam: Insufficient memory");
      }

    strncpy(pls->BaseName, fnam, maxlen-1);
    pls->BaseName[maxlen-1] = '\0';
}

/*--------------------------------------------------------------------------*\
 * plFamInit()
 *
 * Initializes family file parameters.
\*--------------------------------------------------------------------------*/

void
plFamInit(PLStream *pls)
{
    if (pls->family) {
    pls->bytecnt = 0;
    if ( ! pls->member)
        pls->member = 1;
    if ( ! pls->finc)
        pls->finc = 1;
    if ( ! pls->fflen)
        pls->fflen = 1;
    if ( ! pls->bytemax)
        pls->bytemax = PL_FILESIZE_KB * 1000;
    }
}

/*--------------------------------------------------------------------------*\
 * plGetFam()
 *
 * Starts new member file of family file set if necessary.
 *
 * Note each member file is a complete graphics file (can be printed
 * individually), although 'plrender' will treat a family as a single
 * logical file if given the family name instead of the member name.
\*--------------------------------------------------------------------------*/

void
plGetFam(PLStream *pls)
{
    PLFLT xpmm_loc, ypmm_loc;
    if (pls->family) {
    if (pls->bytecnt > pls->bytemax || pls->famadv) {
        PLINT local_page_status = pls->page_status;
        plP_tidy();
        pls->member += pls->finc;
        pls->famadv = 0;
        plP_init();
        /* Restore page status (normally AT_BOP) that was changed
         * to AT_EOP by plP_init. */
        pls->page_status = local_page_status;
        
       /* Apply compensating factor to original xpmm and ypmm so that
        * character aspect ratio is preserved when overall aspect ratio
        * is changed. */
        plP_gpixmm(&xpmm_loc, &ypmm_loc);
        plP_setpxl(xpmm_loc*plsc->caspfactor, ypmm_loc/plsc->caspfactor);
        return;
    }
    }
}

/*--------------------------------------------------------------------------*\
 * plRotPhy()
 *
 * Rotates physical coordinates if necessary for given orientation.
 * Each time orient is incremented, the plot is rotated 90 deg clockwise.
 * Note: this is now used only to rotate by 90 degrees for devices that
 * expect portrait mode.
\*--------------------------------------------------------------------------*/

void
plRotPhy(PLINT orient, PLINT xmin, PLINT ymin, PLINT xmax, PLINT ymax,
     PLINT *px, PLINT *py)
{
    int x, y;

    x = *px;
    y = *py;

    switch (orient%4) {

    case 1:
    *px = xmin + (y - ymin);
    *py = ymin + (xmax - x);
    break;

    case 2:
    *px = xmin + (xmax - x);
    *py = ymin + (ymax - y);
    break;

    case 3:
    *px = xmin + (ymax - y);
    *py = ymin + (x - xmin);
    break;

    default:
    break;          /* do nothing */
    }
}

/*--------------------------------------------------------------------------*\
 * plAllocDev()
 *
 * Allocates a standard PLDev structure for device-specific data, stores
 * the address in pls->dev, and returns the address as well.
\*--------------------------------------------------------------------------*/

PLDev *
plAllocDev(PLStream *pls)
{
    if (pls->dev != NULL)
    free((void *) pls->dev);

    pls->dev = calloc(1, (size_t) sizeof(PLDev));
    if (pls->dev == NULL)
    plexit("plAllocDev: cannot allocate memory\n");

    return (PLDev *) pls->dev;
}

/*--------------------------------------------------------------------------*\
 * plGinInit()
 *
 * Just fills in the PLGraphicsIn with appropriate initial values.
\*--------------------------------------------------------------------------*/

void
plGinInit(PLGraphicsIn *gin)
{
    gin->type = 0;
    gin->state = 0;
    gin->keysym = 0;
    gin->button = 0;
    gin->string[0] = '\0';
    gin->pX = gin->pY = -1;
    gin->dX = gin->dY = 0.;
    gin->wX = gin->wY = 0.;
}

/*--------------------------------------------------------------------------*\
 * plGetInt()
 *
 * Prompts human to input an integer in response to given message.
\*--------------------------------------------------------------------------*/

PLINT
plGetInt(const char *s)
{
    int m;
    int i = 0;
    char line[BUFFER_SIZE];

    while (i++ < 10) {
    fputs(s, stdout);
    plio_fgets(line, sizeof(line), stdin);

#ifdef MSDOS
    m = atoi(line);
    return (m);
#else
    if (sscanf(line, "%d", &m) == 1)
        return (m);
    fprintf(stdout, "No value or value out of range; please try again\n");
#endif
    }
    plexit("Too many tries.");
    return (0);
}

/*--------------------------------------------------------------------------*\
 * plGetFlt()
 *
 * Prompts human to input a float in response to given message.
\*--------------------------------------------------------------------------*/

PLFLT
plGetFlt(const char *s)
{
    PLFLT m;
    double m1;
    int i = 0;
    char line[BUFFER_SIZE];

    while (i++ < 10) {
    fputs(s, stdout);
    plio_fgets(line, sizeof(line), stdin);

#ifdef MSDOS
    m = atof(line);
    return (m);
#else
    if (sscanf(line, "%lf", &m1) == 1) {
        m = (PLFLT) m1;
        return (m);
    }
    fprintf(stdout, "No value or value out of range; please try again\n");
#endif
    }
    plexit("Too many tries.");
    return (0.);
}

/*--------------------------------------------------------------------------*\
 * plstrdup()
 *
 * A replacement for strdup(), which isn't portable.
 * Caller responsible for freeing the allocated memory.
\*--------------------------------------------------------------------------*/

char PLDLLIMPEXP *
plstrdup(const char *src)
{
    char *dest = (char *) malloc( (strlen(src) + 1) * sizeof(char) );
    if (dest != NULL)
    strcpy(dest, src);
    else
    plabort("Out of memory");

    return dest;
}

#ifndef PL_HAVE_SNPRINTF
/*--------------------------------------------------------------------------*\
 * plsnprintf()
 *
 * Dummy function for snprintf(). This function just calls
 * the unsafe function ignoring the string size. This function will
 * rarely be needed if ever.
\*--------------------------------------------------------------------------*/

int 
plsnprintf(char *buffer, int n, const char *format, ...)
{
  int ret;

  va_list args;             
  va_start(args, format);
    ret=vsprintf(buffer, fmt, args);
  va_end( argptr );
 
  /* Check if overrun occured */
  if (ret > n-1) 
    plabort("plsnprintf: buffer overrun");
  
  return ret;
}

/*--------------------------------------------------------------------------*\
 * plsnscanf()
 *
 * Dummy function for snscanf(). This function just calls
 * the unsafe function ignoring the string size. This function will
 * rarely be needed if ever.
\*--------------------------------------------------------------------------*/

int
plsnscanf( const char *buffer, int n, const char *format, ... )
{
  int ret;
  
  va_list argptr;             
  va_start(argptr, format);
    ret=vsscanf(buffer, fmt, args);  
  va_end(argptr);
  
  return ret;
}

#endif /* PL_HAVE_SNPRINTF */

/*--------------------------------------------------------------------------*\
 * plseed()
 *
 * Set the seed for the random number generator included.
\*--------------------------------------------------------------------------*/

void
c_plseed(unsigned int s)
{
  init_genrand(s);
}

/*--------------------------------------------------------------------------*\
 * plrandd()
 *
 * Returns a random number on [0,1]-interval.
\*--------------------------------------------------------------------------*/

PLFLT
c_plrandd(void)
{
  return (PLFLT)(genrand_real1());
}

/*--------------------------------------------------------------------------*\
 * plsave_set_locale()
 *
 * Save LC_NUMERIC locale in a string.  The pointer to that string is
 * returned. Then set LC_NUMERIC to "C" locale.
 * n.b. plsave_set_locale and plrestore_locale should always be used as
 * a pair to surround PLplot code that absolutely requires the
 * LC_NUMERIC "C" locale to be in effect.  It is one of plrestore_locale's
 * responsibilities to free the memory allocated here for the locale
 * string.
\*--------------------------------------------------------------------------*/

char *
plsave_set_locale(void) {
  char * setlocale_ptr;
  char * saved_lc_numeric_locale;

  if(!(saved_lc_numeric_locale = (char *) malloc(100*sizeof(char)))) {
    plexit("plsave_set_locale: out of memory");
  }

  /*save original LC_NUMERIC locale for restore below. */
  if(!(setlocale_ptr = setlocale(LC_NUMERIC, NULL))) {
    plexit("plsave_set_locale: LC_NUMERIC locale could not be determined for NULL locale.\n");
  }
  strncpy(saved_lc_numeric_locale, setlocale_ptr, 100);
  saved_lc_numeric_locale[99] = '\0';

  /* Do not use pldebug since get overflowed stack (infinite recursion)
     if device is interactive (i.e., pls->termin is set). */
  /* comment out fprintf (unless there is some emergency debugging to do)
     because output is too voluminous. */
  /*
fprintf(stderr, "plsave_set_locale: saved LC_NUMERIC locale is \"%s\"\n", saved_lc_numeric_locale);
  */

  if(!(setlocale(LC_NUMERIC, "C"))) {
    plexit("plsave_set_locale: LC_NUMERIC locale could not be set to \"C\"");
  }
  return saved_lc_numeric_locale;
}

/*--------------------------------------------------------------------------*\
 * plrestore_locale()
 *
 * Restore LC_NUMERIC locale string that was determined by
 * plsave_set_locale with the pointer to that string as the argument.
 * Also, free the memory for that string.
\*--------------------------------------------------------------------------*/

void
plrestore_locale(char *saved_lc_numeric_locale) {

  /* Do not use pldebug since get overflowed stack (infinite recursion)
     if device is interactive (i.e., pls->termin is set). */
  /* comment out fprintf (unless there is some emergency debugging to do)
     because output is too voluminous. */
  /*
    fprintf(stderr, "plrestore_locale: restored LC_NUMERIC locale is \"%s\"\n", saved_lc_numeric_locale);
  */

  if(!(setlocale(LC_NUMERIC, saved_lc_numeric_locale))) {
    char msgbuf[1024];
    snprintf(msgbuf,1024,"plrestore_locale: LC_NUMERIC could not be restored to the default \"%s\" locale.\n", saved_lc_numeric_locale);
    plexit(msgbuf);
  }
  free(saved_lc_numeric_locale);
}

---