eterm/libmej/snprintf.c

#include "config.h"
#include "../src/feature.h"

#include "global.h"
#include <errno.h>

static const char cvs_ident[] = "$Id$";

/* 
 * Shamelessly snarfed from Enlightenment...
 * which shamelessly snarfed from sane... 
 * which shamelessly snarfed from LPR 
 * which probably shamelessly snarfed from....
 * 
 * Moved comments to end so I can actually read the code.. cleaned out useless
 * junk....
 */

#if !defined(HAVE_SNPRINTF) || (HAVE_SNPRINTF_BUG == 1)

#ifdef HAVE_STDARG_H
#include <stdarg.h>
#endif

#define VA_LOCAL_DECL va_list ap
#define VA_START(f) va_start(ap, f)
#define VA_SHIFT(v,t) ;		/* no-op for ANSI */
#define VA_END va_end(ap)

/*
 * dopr(): poor man's version of doprintf
 */

static void dopr(char *buffer, const char *format, va_list args);
static void fmtstr(char *value, int ljust, int len, int zpad, int precision);
static void fmtnum(long value, int base, int dosign,
		   int ljust, int len, int zpad, int precision);
static void fmtdouble(int fmt, double value,
		      int ljust, int len, int zpad, int precision);
static void dostr(char *);
static char *output;
static void dopr_outch(int c);
static char *end;
int visible_control = 1;

int
vsnprintf(char *str, size_t count, const char *fmt, va_list args)
{
  str[0] = 0;
  end = str + count - 1;
  dopr(str, fmt, args);
  if (count > 0) {
    end[0] = 0;
  }
  return (strlen(str));
}

#ifdef HAVE_STDARG_H
int
snprintf(char *str, size_t count, const char *fmt,...)
#else
int
snprintf(va_alist)
     va_dcl

#endif
{
#ifndef HAVE_STDARG_H
  char *str;
  size_t count;
  char *fmt;

#endif
  VA_LOCAL_DECL;

  VA_START(fmt);
  VA_SHIFT(str, char *);

  VA_SHIFT(count, size_t);
  VA_SHIFT(fmt, char *);

  (void) vsnprintf(str, count, fmt, ap);
  VA_END;
  return (strlen(str));
}

static void
dopr(char *buffer, const char *format, va_list args)
{
  int ch;
  long value;
  int longflag = 0;
  char *strvalue;
  int ljust;
  int len;
  int zpad;
  int precision;
  int set_precision;
  double dval;

  output = buffer;
  while ((ch = *format++)) {
    switch (ch) {
      case '%':
	ljust = len = zpad = 0;
	precision = -1;
	set_precision = 0;
      nextch:
	ch = *format++;
	switch (ch) {
	  case 0:
	    dostr("**end of format**");
	    return;
	  case '-':
	    ljust = 1;
	    goto nextch;
	  case '.':
	    set_precision = 1;
	    precision = 0;
	    goto nextch;
	  case '*':
	    len = va_arg(args, int);

	    goto nextch;
	  case '0':		/* set zero padding if len not set */
	    if (len == 0 && set_precision == 0)
	      zpad = '0';
	  case '1':
	  case '2':
	  case '3':
	  case '4':
	  case '5':
	  case '6':
	  case '7':
	  case '8':
	  case '9':
	    if (set_precision) {
	      precision = precision * 10 + ch - '0';
	    } else {
	      len = len * 10 + ch - '0';
	    }
	    goto nextch;
	  case 'l':
	    longflag = 1;
	    goto nextch;
	  case 'u':
	  case 'U':
	    /*fmtnum(value,base,dosign,ljust,len, zpad, precision) */
	    if (longflag) {
	      value = va_arg(args, long);
	    } else {
	      value = va_arg(args, int);
	    }
	    fmtnum(value, 10, 0, ljust, len, zpad, precision);
	    break;
	  case 'o':
	  case 'O':
	    /*fmtnum(value,base,dosign,ljust,len, zpad, precision) */
	    if (longflag) {
	      value = va_arg(args, long);
	    } else {
	      value = va_arg(args, int);
	    }
	    fmtnum(value, 8, 0, ljust, len, zpad, precision);
	    break;
	  case 'd':
	  case 'i':
	  case 'D':
	    if (longflag) {
	      value = va_arg(args, long);
	    } else {
	      value = va_arg(args, int);
	    }
	    fmtnum(value, 10, 1, ljust, len, zpad, precision);
	    break;
	  case 'x':
	    if (longflag) {
	      value = va_arg(args, long);
	    } else {
	      value = va_arg(args, int);
	    }
	    fmtnum(value, 16, 0, ljust, len, zpad, precision);
	    break;
	  case 'X':
	    if (longflag) {
	      value = va_arg(args, long);
	    } else {
	      value = va_arg(args, int);
	    }
	    fmtnum(value, -16, 0, ljust, len, zpad, precision);
	    break;
	  case 's':
	    strvalue = va_arg(args, char *);

	    fmtstr(strvalue, ljust, len, zpad, precision);
	    break;
	  case 'c':
	    ch = va_arg(args, int);

	    {
	      char b[2];
	      int vsb = visible_control;

	      b[0] = ch;
	      b[1] = 0;
	      visible_control = 0;
	      fmtstr(b, ljust, len, zpad, precision);
	      visible_control = vsb;
	    }
	    break;
	  case 'f':
	  case 'g':
	    dval = va_arg(args, double);

	    fmtdouble(ch, dval, ljust, len, zpad, precision);
	    break;
	  case '%':
	    dopr_outch(ch);
	    continue;
	  default:
	    dostr("???????");
	}
	longflag = 0;
	break;
      default:
	dopr_outch(ch);
	break;
    }
  }
  *output = 0;
}

/*
 * Format '%[-]len[.precision]s'
 * -   = left justify (ljust)
 * len = minimum length
 * precision = numbers of chars in string to use
 */
static void
fmtstr(char *value, int ljust, int len, int zpad, int precision)
{
  int padlen, strlen, i, c;	/* amount to pad */

  zpad = 0;
  if (value == 0) {
    value = "<NULL>";
  }
  if (precision > 0) {
    strlen = precision;
  } else {
    /* cheap strlen so you do not have library call */
    for (strlen = 0; (c = value[strlen]); ++strlen) {
      if (visible_control && iscntrl(c) && !isspace(c)) {
	++strlen;
      }
    }
  }
  padlen = len - strlen;
  if (padlen < 0)
    padlen = 0;
  if (ljust)
    padlen = -padlen;
  while (padlen > 0) {
    dopr_outch(' ');
    --padlen;
  }
  /* output characters */
  for (i = 0; (c = value[i]); ++i) {
    if (visible_control && iscntrl(c) && !isspace(c)) {
      dopr_outch('^');
      c = ('@' | (c & 0x1F));
    }
    dopr_outch(c);
  }
  while (padlen < 0) {
    dopr_outch(' ');
    ++padlen;
  }
}

static void
fmtnum(long value, int base, int dosign, int ljust,
       int len, int zpad, int precision)
{
  int signvalue = 0;
  unsigned long uvalue;
  char convert[20];
  int place = 0;
  int padlen = 0;		/* amount to pad */
  int caps = 0;

  precision = 0;
  /* DEBUGP(("value 0x%x, base %d, dosign %d, ljust %d, len %d, zpad %d\n",
   * value, base, dosign, ljust, len, zpad )); */
  uvalue = value;
  if (dosign) {
    if (value < 0) {
      signvalue = '-';
      uvalue = -value;
    }
  }
  if (base < 0) {
    caps = 1;
    base = -base;
  }
  do {
    convert[place++] =
	(caps ? "0123456789ABCDEF" : "0123456789abcdef")
	[uvalue % (unsigned) base];
    uvalue = (uvalue / (unsigned) base);
  }
  while (uvalue);
  convert[place] = 0;
  padlen = len - place;
  if (padlen < 0)
    padlen = 0;
  if (ljust)
    padlen = -padlen;
  /* DEBUGP(( "str '%s', place %d, sign %c, padlen %d\n",
   * convert,place,signvalue,padlen)); */
  if (zpad && padlen > 0) {
    if (signvalue) {
      dopr_outch(signvalue);
      --padlen;
      signvalue = 0;
    }
    while (padlen > 0) {
      dopr_outch(zpad);
      --padlen;
    }
  }
  while (padlen > 0) {
    dopr_outch(' ');
    --padlen;
  }
  if (signvalue)
    dopr_outch(signvalue);
  while (place > 0)
    dopr_outch(convert[--place]);
  while (padlen < 0) {
    dopr_outch(' ');
    ++padlen;
  }
}

static void
fmtdouble(int fmt, double value, int ljust, int len, int zpad, int precision)
{
  char convert[128];
  char fmtstr[128];
  int l;

  zpad = 0;
  if (len == 0)
    len = 10;
  if (len > (int) sizeof(convert) - 10) {
    len = (int) sizeof(convert) - 10;
  }
  if (precision > (int) sizeof(convert) - 10) {
    precision = (int) sizeof(convert) - 10;
  }
  if (precision > len)
    precision = len;
  strcpy(fmtstr, "%");
  if (ljust)
    strcat(fmtstr, "-");
  if (len) {
    sprintf(fmtstr + strlen(fmtstr), "%d", len);
  }
  if (precision > 0) {
    sprintf(fmtstr + strlen(fmtstr), ".%d", precision);
  }
  l = strlen(fmtstr);
  fmtstr[l] = fmt;
  fmtstr[l + 1] = 0;
  sprintf(convert, fmtstr, value);
  dostr(convert);
}

static void
dostr(char *str)
{
  while (*str)
    dopr_outch(*str++);
}

static void
dopr_outch(int c)
{
  if (end == 0 || output < end) {
    *output++ = c;
  }
}

/**************************************************************
 * Original:
 * Patrick Powell Tue Apr 11 09:48:21 PDT 1995
 * A bombproof version of doprnt (dopr) included.
 * Sigh.  This sort of thing is always nasty do deal with.  Note that
 * the version here does not include floating point...
 *
 * plp_snprintf() is used instead of sprintf() as it does limit checks
 * for string length.  This covers a nasty loophole.
 *
 * The other functions are there to prevent NULL pointers from
 * causing nast effects.
 **************************************************************/

/***************************************************************************
 * LPRng - An Extended Print Spooler System
 *
 * Copyright 1988-1997, Patrick Powell, San Diego, CA
 *     papowell@sdsu.edu
 * See below for conditions of use.
 *
 ***************************************************************************
 * MODULE: snprintf.c
 * PURPOSE: LPRng version of printf - absolutely bombproof (hopefully!)
 **************************************************************************/

/*
 * The "Artistic License"
 * 
 * Preamble
 * 
 * The intent of this document is to state the conditions under which a
 * Package may be copied, such that the Copyright Holder maintains some
 * semblance of artistic control over the development of the package,
 * while giving the users of the package the right to use and distribute
 * the Package in a more-or-less customary fashion, plus the right to make
 * reasonable modifications.
 * 
 * Definitions:
 * 
 * "Package" refers to the collection of files distributed by the
 * Copyright Holder, and derivatives of that collection of files
 * created through textual modification.
 * 
 * "Standard Version" refers to such a Package if it has not been
 * modified, or has been modified in accordance with the wishes
 * of the Copyright Holder as specified below.
 * 
 * "Copyright Holder" is whoever is named in the copyright or
 * copyrights for the package.
 * 
 * "You" is you, if you are thinking about copying or distributing
 * this Package.
 * 
 * "Reasonable copying fee" is whatever you can justify on the
 * basis of media cost, duplication charges, time of people involved,
 * and so on.  (You will not be required to justify it to the
 * Copyright Holder, but only to the computing community at large
 * as a market that must bear the fee.)
 * 
 * "Freely Available" means that no fee is charged for the item
 * itself, though there may be fees involved in handling the item.
 * It also means that recipients of the item may redistribute it
 * under the same conditions they received it.
 * 
 * 1. You may make and give away verbatim copies of the source form of the
 * Standard Version of this Package without restriction, provided that you
 * duplicate all of the original copyright notices and associated disclaimers.
 * 
 * 2. You may apply bug fixes, portability fixes and other modifications
 * derived from the Public Domain or from the Copyright Holder.  A Package
 * modified in such a way shall still be considered the Standard Version.
 * 
 * 3. You may otherwise modify your copy of this Package in any way, provided
 * that you insert a prominent notice in each changed file stating how and
 * when you changed that file, and provided that you do at least ONE of the
 * following:
 * 
 * a) place your modifications in the Public Domain or otherwise make them
 * Freely Available, such as by posting said modifications to Usenet or
 * an equivalent medium, or placing the modifications on a major archive
 * site such as uunet.uu.net, or by allowing the Copyright Holder to include
 * your modifications in the Standard Version of the Package.
 * 
 * b) use the modified Package only within your corporation or organization.
 * 
 * c) rename any non-standard executables so the names do not conflict
 * with standard executables, which must also be provided, and provide
 * a separate manual page for each non-standard executable that clearly
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 * 
 * d) make other distribution arrangements with the Copyright Holder.
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 * 4. You may distribute the programs of this Package in object code or
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 * a) distribute a Standard Version of the executables and library files,
 * together with instructions (in the manual page or equivalent) on where
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 * you may distribute this Package in aggregate with other (possibly
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 * 
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 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 * 
 * The End
 */

#endif /* HAVE_SNPRINTF */