zio.c

Calc Software Package for Number Calc

/*
 * zio - scanf and printf routines for arbitrary precision integers
 *
 * Copyright (C) 1999-2006  David I. Bell
 *
 * Calc is open software; you can redistribute it and/or modify it under
 * the terms of the version 2.1 of the GNU Lesser General Public License
 * as published by the Free Software Foundation.
 *
 * Calc 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 Lesser General
 * Public License for more details.
 *
 * A copy of version 2.1 of the GNU Lesser General Public License is
 * distributed with calc under the filename COPYING-LGPL.  You should have
 * received a copy with calc; if not, write to Free Software Foundation, Inc.
 * 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
 *
 * @(#) $Revision: 29.8 $
 * @(#) $Id: zio.c,v 29.8 2006/06/01 16:21:37 chongo Exp $
 * @(#) $Source: /usr/local/src/cmd/calc/RCS/zio.c,v $
 *
 * Under source code control:	1993/07/30 19:42:48
 * File existed as early as:	1993
 *
 * Share and enjoy!  :-)	http://www.isthe.com/chongo/tech/comp/calc/
 */


#include <stdio.h>
#include "config.h"
#include "zmath.h"
#include "args.h"


#define OUTBUFSIZE	200		/* realloc size for output buffers */

#define PUTCHAR(ch)		math_chr(ch)
#define PUTSTR(str)		math_str(str)
#define PRINTF1(fmt, a1)		math_fmt(fmt, a1)
#define PRINTF2(fmt, a1, a2)		math_fmt(fmt, a1, a2)
#define PRINTF3(fmt, a1, a2, a3)	math_fmt(fmt, a1, a2, a3)
#define PRINTF4(fmt, a1, a2, a3, a4)	math_fmt(fmt, a1, a2, a3, a4)


/*
 * Output state that has been saved when diversions are done.
 */
typedef struct iostate IOSTATE;
struct iostate {
	IOSTATE *oldiostates;		/* previous saved state */
	long outdigits;			/* digits for output */
	int outmode;			/* output mode */
	int outmode2;			/* secondary output mode */
	FILE *outfp;			/* file unit for output (if any) */
	char *outbuf;			/* output string buffer (if any) */
	size_t outbufsize;		/* current size of string buffer */
	size_t outbufused;		/* space used in string buffer */
	BOOL outputisstring;		/* TRUE if output is to string buffer */
};


static IOSTATE	*oldiostates = NULL;	/* list of saved output states */
static FILE	*outfp = NULL;		/* file unit for output */
static char	*outbuf = NULL;		/* current diverted buffer */
static BOOL	outputisstring = FALSE;
static size_t	outbufsize;
static size_t	outbufused;


/*
 * zio_init - perform needed initilization work
 *
 * On some systems, one cannot initialize a pointer to a FILE *.
 * This routine, called once at startup is a work-a-round for
 * systems with such bogons.
 */
void
zio_init(void)
{
	static int done = 0;	/* 1 => routine already called */

	if (!done) {
		outfp = stdout;
		done = 1;
	}
}


/*
 * Routine to output a character either to a FILE
 * handle or into a string.
 */
void
math_chr(int ch)
{
	char	*cp;

	if (!outputisstring) {
		fputc(ch, outfp);
		return;
	}
	if (outbufused >= outbufsize) {
		cp = (char *)realloc(outbuf, outbufsize + OUTBUFSIZE + 1);
		if (cp == NULL) {
			math_error("Cannot realloc output string");
			/*NOTREACHED*/
		}
		outbuf = cp;
		outbufsize += OUTBUFSIZE;
	}
	outbuf[outbufused++] = (char)ch;
}


/*
 * Routine to output a null-terminated string either
 * to a FILE handle or into a string.
 */
void
math_str(char *str)
{
	char	*cp;
	size_t	len;

	if (!outputisstring) {
		fputs(str, outfp);
		return;
	}
	len = strlen(str);
	if ((outbufused + len) > outbufsize) {
		cp = (char *)realloc(outbuf, outbufsize + len + OUTBUFSIZE + 1);
		if (cp == NULL) {
			math_error("Cannot realloc output string");
			/*NOTREACHED*/
		}
		outbuf = cp;
		outbufsize += (len + OUTBUFSIZE);
	}
	memcpy(&outbuf[outbufused], str, len);
	outbufused += len;
}


/*
 * Output a null-terminated string either to a FILE handle or into a string,
 * padded with spaces as needed so as to fit within the specified width.
 * If width is positive, the spaces are added at the front of the string.
 * If width is negative, the spaces are added at the end of the string.
 * The complete string is always output, even if this overflows the width.
 * No characters within the string are handled specially.
 */
void
math_fill(char *str, long width)
{
	if (width > 0) {
		width -= (long)strlen(str);
		while (width-- > 0)
			PUTCHAR(' ');
		PUTSTR(str);
	} else {
		width += (long)strlen(str);
		PUTSTR(str);
		while (width++ < 0)
			PUTCHAR(' ');
	}
}


/*
 * Routine to output a printf-style formatted string either
 * to a FILE handle or into a string.
 */
void
math_fmt(char *fmt, ...)
{
	va_list ap;
	char buf[BUFSIZ+1];

	va_start(ap, fmt);
	vsnprintf(buf, BUFSIZ, fmt, ap);
	va_end(ap);
	buf[BUFSIZ] = '\0';
	math_str(buf);
}


/*
 * Flush the current output stream.
 */
void
math_flush(void)
{
	if (!outputisstring)
		fflush(outfp);
}


/*
 * Divert further output so that it is saved into a string that will be
 * returned later when the diversion is completed.  The current state of
 * output is remembered for later restoration.	Diversions can be nested.
 * Output diversion is only intended for saving output to "stdout".
 */
void
math_divertio(void)
{
	register IOSTATE *sp;

	sp = (IOSTATE *) malloc(sizeof(IOSTATE));
	if (sp == NULL) {
		math_error("No memory for diverting output");
		/*NOTREACHED*/
	}
	sp->oldiostates = oldiostates;
	sp->outdigits = conf->outdigits;
	sp->outmode = conf->outmode;
	sp->outmode2 = conf->outmode2;
	sp->outfp = outfp;
	sp->outbuf = outbuf;
	sp->outbufsize = outbufsize;
	sp->outbufused = outbufused;
	sp->outputisstring = outputisstring;

	outbufused = 0;
	outbufsize = 0;
	outbuf = (char *) malloc(OUTBUFSIZE + 1);
	if (outbuf == NULL) {
		math_error("Cannot allocate divert string");
		/*NOTREACHED*/
	}
	outbufsize = OUTBUFSIZE;
	outputisstring = TRUE;
	oldiostates = sp;
}


/*
 * Undivert output and return the saved output as a string.  This also
 * restores the output state to what it was before the diversion began.
 * The string needs freeing by the caller when it is no longer needed.
 */
char *
math_getdivertedio(void)
{
	register IOSTATE *sp;
	char *cp;

	sp = oldiostates;
	if (sp == NULL) {
		math_error("No diverted state to restore");
		/*NOTREACHED*/
	}
	cp = outbuf;
	cp[outbufused] = '\0';
	oldiostates = sp->oldiostates;
	conf->outdigits = sp->outdigits;
	conf->outmode = sp->outmode;
	conf->outmode2 = sp->outmode2;
	outfp = sp->outfp;
	outbuf = sp->outbuf;
	outbufsize = sp->outbufsize;
	outbufused = sp->outbufused;
	outbuf = sp->outbuf;
	outputisstring = sp->outputisstring;
	free(sp);
	return cp;
}


/*
 * Clear all diversions and set output back to the original destination.
 * This is called when resetting the global state of the program.
 */
void
math_cleardiversions(void)
{
	while (oldiostates)
		free(math_getdivertedio());
}


/*
 * Set the output routines to output to the specified FILE stream.
 * This interacts with output diversion in the following manner.
 *	STDOUT	diversion	action
 *	----	---------	------
 *	yes	yes		set output to diversion string again.
 *	yes	no		set output to stdout.
 *	no	yes		set output to specified file.
 *	no	no		set output to specified file.
 */
void
math_setfp(FILE *newfp)
{
	outfp = newfp;
	outputisstring = (oldiostates && (newfp == stdout));
}


/*
 * Set the output mode for numeric output.
 * This also returns the previous mode.
 */
int
math_setmode(int newmode)
{
	int oldmode;

	if ((newmode <= MODE_DEFAULT) || (newmode > MODE_MAX)) {
		math_error("Setting illegal output mode");
		/*NOTREACHED*/
	}
	oldmode = conf->outmode;
	conf->outmode = newmode;
	return oldmode;
}


/*
 * Set the secondary output mode for numeric output.
 * This also returns the previous mode.
 */
int
math_setmode2(int newmode)
{
	int oldmode;

	if (newmode != MODE2_OFF && ((newmode <= MODE_DEFAULT) || (newmode > MODE_MAX))) {
		math_error("Setting illegal secondary output mode");
		/*NOTREACHED*/
	}
	oldmode = conf->outmode2;
	conf->outmode2 = newmode;
	return oldmode;
}


/*
 * Set the number of digits for float or exponential output.
 * This also returns the previous number of digits.
 */
LEN
math_setdigits(LEN newdigits)
{
	LEN olddigits;

	if (newdigits < 0) {
		math_error("Setting illegal number of digits");
		/*NOTREACHED*/
	}
	olddigits = conf->outdigits;
	conf->outdigits = newdigits;
	return olddigits;
}


/*
 * Print an integer value as a hex number.
 * Width is the number of columns to print the number in, including the
 * sign if required.  If zero, no extra output is done.	 If positive,
 * leading spaces are typed if necessary. If negative, trailing spaces are
 * typed if necessary.	The special characters 0x appear to indicate the
 * number is hex.
 */
/*ARGSUSED*/
void
zprintx(ZVALUE z, long width)
{
	register HALF *hp;	/* current word to print */
	int len;		/* number of halfwords to type */
	char *str;

	if (width) {
		math_divertio();
		zprintx(z, 0L);
		str = math_getdivertedio();
		math_fill(str, width);
		free(str);
		return;
	}
	len = z.len - 1;
	if (zisneg(z))
		PUTCHAR('-');
	if ((len == 0) && (*z.v <= (HALF) 9)) {
		len = '0' + (int)(*z.v);
		PUTCHAR(len & 0xff);
		return;
	}
	hp = z.v + len;
#if BASEB == 32
	PRINTF1("0x%lx", (PRINT) *hp--);
	while (--len >= 0) {
		PRINTF1("%08lx", (PRINT) *hp--);
	}
#else /* BASEB == 32 */