util.c

#ifndef lint
static char *RCSid = "$Id: util.c,v 1.9 1998/11/06 22:07:07 lhecking Exp $";
#endif

/* GNUPLOT - util.c */

/*[
 * Copyright 1986 - 1993, 1998   Thomas Williams, Colin Kelley
 *
 * Permission to use, copy, and distribute this software and its
 * documentation for any purpose with or without fee is hereby granted,
 * provided that the above copyright notice appear in all copies and
 * that both that copyright notice and this permission notice appear
 * in supporting documentation.
 *
 * Permission to modify the software is granted, but not the right to
 * distribute the complete modified source code.  Modifications are to
 * be distributed as patches to the released version.  Permission to
 * distribute binaries produced by compiling modified sources is granted,
 * provided you
 *   1. distribute the corresponding source modifications from the
 *    released version in the form of a patch file along with the binaries,
 *   2. add special version identification to distinguish your version
 *    in addition to the base release version number,
 *   3. provide your name and address as the primary contact for the
 *    support of your modified version, and
 *   4. retain our contact information in regard to use of the base
 *    software.
 * Permission to distribute the released version of the source code along
 * with corresponding source modifications in the form of a patch file is
 * granted with same provisions 2 through 4 for binary distributions.
 *
 * This software is provided "as is" without express or implied warranty
 * to the extent permitted by applicable law.
]*/


#include "plot.h"
#include "setshow.h"		/* for month names etc */


/* TRUE if command just typed; becomes FALSE whenever we
 * send some other output to screen.  If FALSE, the command line
 * will be echoed to the screen before the ^ error message.
 */
TBOOLEAN screen_ok;

static char *num_to_str __PROTO((double r));
static void parse_esc __PROTO((char *instr));

/*
 * chr_in_str() compares the characters in the string of token number t_num
 * with c, and returns TRUE if a match was found.
 */
int chr_in_str(t_num, c)
int t_num;
int c;
{
    register int i;

    if (!token[t_num].is_token)
	return (FALSE);		/* must be a value--can't be equal */
    for (i = 0; i < token[t_num].length; i++) {
	if (input_line[token[t_num].start_index + i] == c)
	    return (TRUE);
    }
    return FALSE;
}


/*
 * equals() compares string value of token number t_num with str[], and
 *   returns TRUE if they are identical.
 */
int equals(t_num, str)
int t_num;
char *str;
{
    register int i;

    if (!token[t_num].is_token)
	return (FALSE);		/* must be a value--can't be equal */
    for (i = 0; i < token[t_num].length; i++) {
	if (input_line[token[t_num].start_index + i] != str[i])
	    return (FALSE);
    }
    /* now return TRUE if at end of str[], FALSE if not */
    return (str[i] == NUL);
}



/*
 * almost_equals() compares string value of token number t_num with str[], and
 *   returns TRUE if they are identical up to the first $ in str[].
 */
int almost_equals(t_num, str)
int t_num;
char *str;
{
    register int i;
    register int after = 0;
    register int start = token[t_num].start_index;
    register int length = token[t_num].length;

    if (!token[t_num].is_token)
	return (FALSE);		/* must be a value--can't be equal */
    for (i = 0; i < length + after; i++) {
	if (str[i] != input_line[start + i]) {
	    if (str[i] != '$')
		return (FALSE);
	    else {
		after = 1;
		start--;	/* back up token ptr */
	    }
	}
    }

    /* i now beyond end of token string */

    return (after || str[i] == '$' || str[i] == NUL);
}



int isstring(t_num)
int t_num;
{

    return (token[t_num].is_token &&
	    (input_line[token[t_num].start_index] == '\'' ||
	     input_line[token[t_num].start_index] == '"'));
}


int isanumber(t_num)
int t_num;
{
    return (!token[t_num].is_token);
}


int isletter(t_num)
int t_num;
{
    return (token[t_num].is_token &&
	    ((isalpha((int)input_line[token[t_num].start_index])) ||
	     (input_line[token[t_num].start_index] == '_')));
}


/*
 * is_definition() returns TRUE if the next tokens are of the form
 *   identifier =
 *              -or-
 *   identifier ( identifer {,identifier} ) =
 */
int is_definition(t_num)
int t_num;
{
    /* variable? */
    if (isletter(t_num) && equals(t_num + 1, "="))
	return 1;

    /* function? */
    /* look for dummy variables */
    if (isletter(t_num) && equals(t_num + 1, "(") && isletter(t_num + 2)) {
	t_num += 3;		/* point past first dummy */
	while (equals(t_num, ",")) {
	    if (!isletter(++t_num))
		return 0;
	    t_num += 1;
	}
	return (equals(t_num, ")") && equals(t_num + 1, "="));
    }
    /* neither */
    return 0;
}



/*
 * copy_str() copies the string in token number t_num into str, appending
 *   a null.  No more than max chars are copied (including \0).
 */
void copy_str(str, t_num, max)
char str[];
int t_num;
int max;
{
    register int i = 0;
    register int start = token[t_num].start_index;
    register int count;

    if ((count = token[t_num].length) >= max) {
	count = max - 1;
	FPRINTF((stderr, "str buffer overflow in copy_str"));
    }
    do {
	str[i++] = input_line[start++];
    } while (i != count);
    str[i] = NUL;
}

/* length of token string */
int token_len(t_num)
int t_num;
{
    return (token[t_num].length);
}

/*
 * quote_str() does the same thing as copy_str, except it ignores the
 *   quotes at both ends.  This seems redundant, but is done for
 *   efficency.
 */
void quote_str(str, t_num, max)
char str[];
int t_num;
int max;
{
    register int i = 0;
    register int start = token[t_num].start_index + 1;
    register int count;

    if ((count = token[t_num].length - 2) >= max) {
	count = max - 1;
	FPRINTF((stderr, "str buffer overflow in quote_str"));
    }
    if (count > 0) {
	do {
	    str[i++] = input_line[start++];
	} while (i != count);
    }
    str[i] = NUL;
    /* convert \t and \nnn (octal) to char if in double quotes */
    if (input_line[token[t_num].start_index] == '"')
	parse_esc(str);
}


/*
 * capture() copies into str[] the part of input_line[] which lies between
 * the begining of token[start] and end of token[end].
 */
void capture(str, start, end, max)
char str[];
int start, end;
int max;
{
    register int i, e;

    e = token[end].start_index + token[end].length;
    if (e - token[start].start_index >= max) {
	e = token[start].start_index + max - 1;
	FPRINTF((stderr, "str buffer overflow in capture"));
    }
    for (i = token[start].start_index; i < e && input_line[i] != NUL; i++)
	*str++ = input_line[i];
    *str = NUL;
}


/*
 * m_capture() is similar to capture(), but it mallocs storage for the
 * string.
 */
void m_capture(str, start, end)
char **str;
int start, end;
{
    register int i, e;
    register char *s;

    if (*str)			/* previous pointer to malloc'd memory there */
	free(*str);
    e = token[end].start_index + token[end].length;
    *str = gp_alloc((unsigned long) (e - token[start].start_index + 1), "string");
    s = *str;
    for (i = token[start].start_index; i < e && input_line[i] != NUL; i++)
	*s++ = input_line[i];
    *s = NUL;
}


/*
 *    m_quote_capture() is similar to m_capture(), but it removes
 quotes from either end if the string.
 */
void m_quote_capture(str, start, end)
char **str;
int start, end;
{
    register int i, e, escflag = 0;
    register char *s;

    if (*str)			/* previous pointer to malloc'd memory there */
	free(*str);
    e = token[end].start_index + token[end].length - 1;
    *str = gp_alloc((unsigned long) (e - token[start].start_index + 1), "string");
    s = *str;
    for (i = token[start].start_index + 1; i < e && input_line[i] != NUL; i++)
	if ((*s++ = input_line[i]) == '\\') ++escflag;
    *s = NUL;
    if (escflag) parse_esc(*str);
}


void convert(val_ptr, t_num)
struct value *val_ptr;
int t_num;
{
    *val_ptr = token[t_num].l_val;
}

static char *num_to_str(r)
double r;
{
    static int i = 0;
    static char s[4][25];
    int j = i++;

    if (i > 3)
	i = 0;

    sprintf(s[j], "%.15g", r);
    if (strchr(s[j], '.') == NULL &&
	strchr(s[j], 'e') == NULL &&
	strchr(s[j], 'E') == NULL)
	strcat(s[j], ".0");

    return s[j];
}

void disp_value(fp, val)
FILE *fp;
struct value *val;
{
    switch (val->type) {
    case INTGR:
	fprintf(fp, "%d", val->v.int_val);
	break;
    case CMPLX:
	if (val->v.cmplx_val.imag != 0.0)
	    fprintf(fp, "{%s, %s}",
		    num_to_str(val->v.cmplx_val.real),
		    num_to_str(val->v.cmplx_val.imag));
	else
	    fprintf(fp, "%s",
		    num_to_str(val->v.cmplx_val.real));
	break;
    default:
	int_error("unknown type in disp_value()", NO_CARET);
    }
}


double real(val)		/* returns the real part of val */
struct value *val;
{
    switch (val->type) {
    case INTGR:
	return ((double) val->v.int_val);
    case CMPLX:
	return (val->v.cmplx_val.real);
    }
    int_error("unknown type in real()", NO_CARET);
    /* NOTREACHED */
    return ((double) 0.0);
}


double imag(val)		/* returns the imag part of val */
struct value *val;
{
    switch (val->type) {
    case INTGR:
	return (0.0);
    case CMPLX:
	return (val->v.cmplx_val.imag);
    }
    int_error("unknown type in imag()", NO_CARET);
    /* NOTREACHED */
    return ((double) 0.0);
}



double magnitude(val)		/* returns the magnitude of val */
struct value *val;
{
    switch (val->type) {
    case INTGR:
	return ((double) abs(val->v.int_val));
    case CMPLX:
	return (sqrt(val->v.cmplx_val.real *
		     val->v.cmplx_val.real +
		     val->v.cmplx_val.imag *
		     val->v.cmplx_val.imag));
    }
    int_error("unknown type in magnitude()", NO_CARET);
    /* NOTREACHED */
    return ((double) 0.0);
}



double angle(val)		/* returns the angle of val */
struct value *val;
{
    switch (val->type) {
    case INTGR:
	return ((val->v.int_val >= 0) ? 0.0 : Pi);
    case CMPLX:
	if (val->v.cmplx_val.imag == 0.0) {
	    if (val->v.cmplx_val.real >= 0.0)
		return (0.0);
	    else
		return (Pi);
	}
	return (atan2(val->v.cmplx_val.imag,
		      val->v.cmplx_val.real));
    }
    int_error("unknown type in angle()", NO_CARET);
    /* NOTREACHED */
    return ((double) 0.0);
}


struct value *
 Gcomplex(a, realpart, imagpart)
struct value *a;
double realpart, imagpart;
{
    a->type = CMPLX;
    a->v.cmplx_val.real = realpart;
    a->v.cmplx_val.imag = imagpart;
    return (a);
}


struct value *
 Ginteger(a, i)
struct value *a;
int i;
{
    a->type = INTGR;
    a->v.int_val = i;
    return (a);
}


void os_error(str, t_num)
char str[];
int t_num;
{
#ifdef VMS
    static status[2] =
    {1, 0};			/* 1 is count of error msgs */
#endif /* VMS */

    register int i;

    /* reprint line if screen has been written to */

    if (t_num != NO_CARET) {	/* put caret under error */
	if (!screen_ok)
	    fprintf(stderr, "\n%s%s\n", PROMPT, input_line);

	for (i = 0; i < sizeof(PROMPT) - 1; i++)
	    (void) putc(' ', stderr);
	for (i = 0; i < token[t_num].start_index; i++) {
	    (void) putc((input_line[i] == '\t') ? '\t' : ' ', stderr);
	}
	(void) putc('^', stderr);
	(void) putc('\n', stderr);
    }
    for (i = 0; i < sizeof(PROMPT) - 1; i++)
	(void) putc(' ', stderr);
    fprintf(stderr, "%s\n", str);

    for (i = 0; i < sizeof(PROMPT) - 1; i++)
	(void) putc(' ', stderr);
    if (!interactive) {
	if (infile_name != NULL)
	    fprintf(stderr, "\"%s\", line %d: ", infile_name, inline_num);
	else
	    fprintf(stderr, "line %d: ", inline_num);
    }


#ifdef VMS
    status[1] = vaxc$errno;
    sys$putmsg(status);
    (void) putc('\n', stderr);
#else /* VMS */
    fprintf(stderr, "(%s)\n\n", strerror(errno));
#endif /* VMS */

    bail_to_command_line();
}


void int_error(str, t_num)
char str[];
int t_num;
{
    register int i;

    /* reprint line if screen has been written to */

    if (t_num != NO_CARET) {	/* put caret under error */
	if (!screen_ok)
	    fprintf(stderr, "\n%s%s\n", PROMPT, input_line);

	for (i = 0; i < sizeof(PROMPT) - 1; i++)
	    (void) putc(' ', stderr);
	for (i = 0; i < token[t_num].start_index; i++) {
	    (void) putc((input_line[i] == '\t') ? '\t' : ' ', stderr);
	}
	(void) putc('^', stderr);
	(void) putc('\n', stderr);
    }
    for (i = 0; i < sizeof(PROMPT) - 1; i++)
	(void) putc(' ', stderr);
    if (!interactive) {
	if (infile_name != NULL)
	    fprintf(stderr, "\"%s\", line %d: ", infile_name, inline_num);
	else
	    fprintf(stderr, "line %d: ", inline_num);
    }
    fprintf(stderr, "%s\n\n", str);

    bail_to_command_line();
}

/* Warn without bailing out to command line. Not a user error */
void int_warn(str, t_num)
char str[];
int t_num;
{
    register int i;

    /* reprint line if screen has been written to */

    if (t_num != NO_CARET) {	/* put caret under error */
	if (!screen_ok)
	    fprintf(stderr, "\n%s%s\n", PROMPT, input_line);

	for (i = 0; i < sizeof(PROMPT) - 1; i++)
	    (void) putc(' ', stderr);
	for (i = 0; i < token[t_num].start_index; i++) {
	    (void) putc((input_line[i] == '\t') ? '\t' : ' ', stderr);
	}
	(void) putc('^', stderr);
	(void) putc('\n', stderr);
    }
    for (i = 0; i < sizeof(PROMPT) - 1; i++)
	(void) putc(' ', stderr);
    if (!interactive) {
	if (infile_name != NULL)
	    fprintf(stderr, "\"%s\", line %d: ", infile_name, inline_num);
	else
	    fprintf(stderr, "line %d: ", inline_num);
    }
    fprintf(stderr, "warning: %s\n", str);

}				/* int_warn */

/* Lower-case the given string (DFK) */
/* Done in place. */
void lower_case(s)
char *s;
{
    register char *p = s;

    while (*p != NUL) {
	if (isupper((int)*p))
	    *p = tolower(*p);
	p++;
    }
}

/* Squash spaces in the given string (DFK) */
/* That is, reduce all multiple white-space chars to single spaces */
/* Done in place. */
void squash_spaces(s)
char *s;
{
    register char *r = s;	/* reading point */
    register char *w = s;	/* writing point */
    TBOOLEAN space = FALSE;	/* TRUE if we've already copied a space */

    for (w = r = s; *r != NUL; r++) {
	if (isspace((int)*r)) {
	    /* white space; only copy if we haven't just copied a space */
	    if (!space) {
		space = TRUE;
		*w++ = ' ';
	    }			/* else ignore multiple spaces */
	} else {
	    /* non-space character; copy it and clear flag */
	    *w++ = *r;
	    space = FALSE;
	}
    }
    *w = NUL;			/* null terminate string */
}


static void parse_esc(instr)
char *instr;
{
    char *s = instr, *t = instr;

    /* the string will always get shorter, so we can do the
     * conversion in situ
     */

    while (*s != NUL) {
	if (*s == '\\') {
	    s++;
	    if (*s == '\\') {
		*t++ = '\\';
		s++;
	    } else if (*s == 'n') {
		*t++ = '\n';
		s++;
	    } else if (*s == 'r') {
		*t++ = '\r';
		s++;
	    } else if (*s == 't') {
		*t++ = '\t';
		s++;
	    } else if (*s == '\"') {
		*t++ = '\"';
		s++;
	    } else if (*s >= '0' && *s <= '7') {
		int i, n;
		if (sscanf(s, "%o%n", &i, &n) > 0) {
		    *t++ = i;
		    s += n;
		} else {
		    /* int_error("illegal octal number ", c_token); */
		    *t++ = '\\';
		    *t++ = *s++;
		}
	    }
	} else {
	    *t++ = *s++;
	}
    }
    *t = NUL;
}