doprnt.c 5.06 KB
Newer Older
Joseph Arceneaux's avatar
Joseph Arceneaux committed
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
/* Output like sprintf to a buffer of specified size.
   Also takes args differently: pass one pointer to an array of strings
   in addition to the format string which is separate.
   Copyright (C) 1985 Free Software Foundation, Inc.

This file is part of GNU Emacs.

GNU Emacs is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 1, or (at your option)
any later version.

GNU Emacs 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 General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU Emacs; see the file COPYING.  If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */


#include <stdio.h>
#include <ctype.h>

26 27 28 29 30 31 32 33
/* Generate output from a format-spec FORMAT,
   terminated at position FORMAT_END.
   Output goes in BUFFER, which has room for BUFSIZE chars.
   If the output does not fit, truncate it to fit.
   Returns the number of characters stored into BUFFER.
   ARGS points to the vector of arguments, and NARGS says how many.
   A double counts as two arguments.  */

Joseph Arceneaux's avatar
Joseph Arceneaux committed
34 35 36 37 38 39 40 41 42 43 44
doprnt (buffer, bufsize, format, format_end, nargs, args)
     char *buffer;
     register int bufsize;
     char *format;
     char *format_end;
     int nargs;
     char **args;
{
  int cnt = 0;			/* Number of arg to gobble next */
  register char *fmt = format;	/* Pointer into format string */
  register char *bufptr = buffer; /* Pointer into output buffer.. */
45 46 47 48 49 50 51 52
  /* Use this for sprintf unless we need something really big.  */
  char tembuf[100];
  /* Size of sprintf_buffer.  */
  int size_allocated = 100;
  /* Buffer to use for sprintf.  Either tembuf or same as BIG_BUFFER.  */
  char *sprintf_buffer = tembuf;
  /* Buffer we have got with malloc.  */
  char *big_buffer = 0;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
53 54 55 56 57 58 59 60 61 62
  register int tem;
  char *string;
  char fmtcpy[20];
  int minlen;
  int size;			/* Field width factor; e.g., %90d */

  if (format_end == 0)
    format_end = format + strlen (format);

  bufsize--;
Jim Blandy's avatar
Jim Blandy committed
63 64
  while (fmt != format_end && bufsize > 0)	/* Loop until end of format
						   string or buffer full */
Joseph Arceneaux's avatar
Joseph Arceneaux committed
65 66 67
    {
      if (*fmt == '%')	/* Check for a '%' character */
	{
68 69
	  int size_bound;

Joseph Arceneaux's avatar
Joseph Arceneaux committed
70 71 72 73 74 75 76 77 78 79 80 81
	  fmt++;
	  /* Copy this one %-spec into fmtcopy.  */
	  string = fmtcpy;
	  *string++ = '%';
	  while (1)
	    {
	      *string++ = *fmt;
	      if (! (*fmt >= '0' && *fmt <= '9') && *fmt != '-' && *fmt != ' ')
		break;
	      fmt++;
	    }
	  *string = 0;
82 83 84 85 86 87 88 89 90 91 92 93
	  /* Get an idea of how much space we might need.  */
	  size_bound = atoi (&fmtcpy[1]) + 50;
	  /* Make sure we have that much.  */
	  if (size_bound > size_allocated)
	    {
	      if (big_buffer)
		big_buffer = (char *) xrealloc (big_buffer, size_bound);
	      else
		big_buffer = (char *) xmalloc (size_bound);
	      sprintf_buffer = big_buffer;
	      size_allocated = size_bound;
	    }
Joseph Arceneaux's avatar
Joseph Arceneaux committed
94 95 96 97 98 99 100 101 102 103 104 105
	  minlen = 0;
	  switch (*fmt++)
	    {
	    default:
	      error ("Invalid format operation %%%c", fmt[-1]);

/*	    case 'b': */
	    case 'd':
	    case 'o':
	    case 'x':
	      if (cnt == nargs)
		error ("Format string wants too many arguments");
106 107 108
	      sprintf (sprintf_buffer, fmtcpy, args[cnt++]);
	      /* Now copy into final output, truncating as nec.  */
	      string = sprintf_buffer;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
109 110
	      goto doit;

111 112 113 114 115 116 117 118 119 120 121 122 123 124 125
	    case 'f':
	    case 'e':
	    case 'g':
	      {
		union { double d; char *half[2]; } u;
		if (cnt + 1 == nargs)
		  error ("Format string wants too many arguments");
		u.half[0] = args[cnt++];
		u.half[1] = args[cnt++];
		sprintf (sprintf_buffer, fmtcpy, u.d);
		/* Now copy into final output, truncating as nec.  */
		string = sprintf_buffer;
		goto doit;
	      }

Joseph Arceneaux's avatar
Joseph Arceneaux committed
126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178
	    case 'S':
	      string[-1] = 's';
	    case 's':
	      if (cnt == nargs)
		error ("Format string wants too many arguments");
	      string = args[cnt++];
	      if (fmtcpy[1] != 's')
		minlen = atoi (&fmtcpy[1]);
	      /* Copy string into final output, truncating if no room.  */
	    doit:
	      tem = strlen (string);
	      if (minlen > 0)
		{
		  while (minlen > tem && bufsize > 0)
		    {
		      *bufptr++ = ' ';
		      bufsize--;
		      minlen--;
		    }
		  minlen = 0;
		}
	      if (tem > bufsize)
		tem = bufsize;
	      strncpy (bufptr, string, tem);
	      bufptr += tem;
	      bufsize -= tem;
	      if (minlen < 0)
		{
		  while (minlen < - tem && bufsize > 0)
		    {
		      *bufptr++ = ' ';
		      bufsize--;
		      minlen++;
		    }
		  minlen = 0;
		}
	      continue;

	    case 'c':
	      if (cnt == nargs)
		error ("Format string wants too many arguments");
	      *bufptr++ = (int) args[cnt++];
	      bufsize--;
	      continue;

	    case '%':
	      fmt--;    /* Drop thru and this % will be treated as normal */
	    }
	}
      *bufptr++ = *fmt++;	/* Just some characters; Copy 'em */
      bufsize--;
    };

179 180 181 182
  /* If we had to malloc something, free it.  */
  if (big_buffer)
    free (big_buffer);

Joseph Arceneaux's avatar
Joseph Arceneaux committed
183 184 185
  *bufptr = 0;		/* Make sure our string end with a '\0' */
  return bufptr - buffer;
}