src/tparam.c

   1 /* Merge parameters into a termcap entry string.
   2    Copyright (C) 1985, 1987, 1993, 1995, 2000, 2001, 2002, 2003, 2004,
   3                  2005, 2006, 2007, 2008  Free Software Foundation, Inc.
   4
   5 This program is free software; you can redistribute it and/or modify
   6 it under the terms of the GNU General Public License as published by
   7 the Free Software Foundation; either version 2, or (at your option)
   8 any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with this program; see the file COPYING.  If not, write to
  17 the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  18 Boston, MA 02110-1301, USA.  */
  19
  20 /* Emacs config.h may rename various library functions such as malloc.  */
  21 #include <config.h>
  22 #include <setjmp.h>
  23 #include "lisp.h"               /* for xmalloc */
  24
  25 #ifndef NULL
  26 #define NULL (char *) 0
  27 #endif
  28 \f
  29 /* Assuming STRING is the value of a termcap string entry
  30    containing `%' constructs to expand parameters,
  31    merge in parameter values and store result in block OUTSTRING points to.
  32    LEN is the length of OUTSTRING.  If more space is needed,
  33    a block is allocated with `malloc'.
  34
  35    The value returned is the address of the resulting string.
  36    This may be OUTSTRING or may be the address of a block got with `malloc'.
  37    In the latter case, the caller must free the block.
  38
  39    The fourth and following args to tparam serve as the parameter values.  */
  40
  41 static char *tparam1 (char *string, char *outstring, int len, char *up, char *left, register int *argp);
  42
  43 /* VARARGS 2 */
  44 char *
  45 tparam (char *string, char *outstring, int len, int arg0, int arg1, int arg2, int arg3)
  46 {
  47   int arg[4];
  48
  49   arg[0] = arg0;
  50   arg[1] = arg1;
  51   arg[2] = arg2;
  52   arg[3] = arg3;
  53   return tparam1 (string, outstring, len, NULL, NULL, arg);
  54 }
  55
  56 char *BC;
  57 char *UP;
  58
  59 static char tgoto_buf[50];
  60
  61 char *
  62 tgoto (char *cm, int hpos, int vpos)
  63 {
  64   int args[2];
  65   if (!cm)
  66     return NULL;
  67   args[0] = vpos;
  68   args[1] = hpos;
  69   return tparam1 (cm, tgoto_buf, 50, UP, BC, args);
  70 }
  71
  72 static char *
  73 tparam1 (char *string, char *outstring, int len, char *up, char *left, register int *argp)
  74 {
  75   register int c;
  76   register char *p = string;
  77   register char *op = outstring;
  78   char *outend;
  79   int outlen = 0;
  80
  81   register int tem;
  82   int *old_argp = argp;                 /* can move */
  83   int *fixed_argp = argp;               /* never moves */
  84   int explicit_param_p = 0;             /* set by %p */
  85   int doleft = 0;
  86   int doup = 0;
  87
  88   outend = outstring + len;
  89
  90   while (1)
  91     {
  92       /* If the buffer might be too short, make it bigger.  */
  93       if (op + 5 >= outend)
  94         {
  95           register char *new;
  96           int offset = op - outstring;
  97
  98           if (outlen == 0)
  99             {
 100               outlen = len + 40;
 101               new = (char *) xmalloc (outlen);
 102               memcpy (new, outstring, offset);
 103             }
 104           else
 105             {
 106               outlen *= 2;
 107               new = (char *) xrealloc (outstring, outlen);
 108             }
 109
 110           op = new + offset;
 111           outend = new + outlen;
 112           outstring = new;
 113         }
 114       c = *p++;
 115       if (!c)
 116         break;
 117       if (c == '%')
 118         {
 119           c = *p++;
 120           if (explicit_param_p)
 121             explicit_param_p = 0;
 122           else
 123             tem = *argp;
 124           switch (c)
 125             {
 126             case 'd':           /* %d means output in decimal.  */
 127               if (tem < 10)
 128                 goto onedigit;
 129               if (tem < 100)
 130                 goto twodigit;
 131             case '3':           /* %3 means output in decimal, 3 digits.  */
 132               if (tem > 999)
 133                 {
 134                   *op++ = tem / 1000 + '0';
 135                   tem %= 1000;
 136                 }
 137               *op++ = tem / 100 + '0';
 138             case '2':           /* %2 means output in decimal, 2 digits.  */
 139             twodigit:
 140               tem %= 100;
 141               *op++ = tem / 10 + '0';
 142             onedigit:
 143               *op++ = tem % 10 + '0';
 144               argp++;
 145               break;
 146             case 'p':           /* %pN means use param N for next subst.  */
 147               tem = fixed_argp[(*p++) - '1'];
 148               explicit_param_p = 1;
 149               break;
 150             case 'C':
 151               /* For c-100: print quotient of value by 96, if nonzero,
 152                  then do like %+.  */
 153               if (tem >= 96)
 154                 {
 155                   *op++ = tem / 96;
 156                   tem %= 96;
 157                 }
 158             case '+':           /* %+x means add character code of char x.  */
 159               tem += *p++;
 160             case '.':           /* %. means output as character.  */
 161               if (left)
 162                 {
 163                   /* If want to forbid output of 0 and \n and \t,
 164                      and this is one of them, increment it.  */
 165                   while (tem == 0 || tem == '\n' || tem == '\t')
 166                     {
 167                       tem++;
 168                       if (argp == old_argp)
 169                         doup++, outend -= strlen (up);
 170                       else
 171                         doleft++, outend -= strlen (left);
 172                     }
 173                 }
 174               *op++ = tem ? tem : 0200;
 175             case 'f':           /* %f means discard next arg.  */
 176               argp++;
 177               break;
 178
 179             case 'b':           /* %b means back up one arg (and re-use it).  */
 180               argp--;
 181               break;
 182
 183             case 'r':           /* %r means interchange following two args.  */
 184               argp[0] = argp[1];
 185               argp[1] = tem;
 186               old_argp++;
 187               break;
 188
 189             case '>':           /* %>xy means if arg is > char code of x, */
 190               if (argp[0] > *p++) /* then add char code of y to the arg, */
 191                 argp[0] += *p;  /* and in any case don't output.  */
 192               p++;              /* Leave the arg to be output later.  */
 193               break;
 194
 195             case 'a':           /* %a means arithmetic.  */
 196               /* Next character says what operation.
 197                  Add or subtract either a constant or some other arg.  */
 198               /* First following character is + to add or - to subtract
 199                  or = to assign.  */
 200               /* Next following char is 'p' and an arg spec
 201                  (0100 plus position of that arg relative to this one)
 202                  or 'c' and a constant stored in a character.  */
 203               tem = p[2] & 0177;
 204               if (p[1] == 'p')
 205                 tem = argp[tem - 0100];
 206               if (p[0] == '-')
 207                 argp[0] -= tem;
 208               else if (p[0] == '+')
 209                 argp[0] += tem;
 210               else if (p[0] == '*')
 211                 argp[0] *= tem;
 212               else if (p[0] == '/')
 213                 argp[0] /= tem;
 214               else
 215                 argp[0] = tem;
 216
 217               p += 3;
 218               break;
 219
 220             case 'i':           /* %i means add one to arg, */
 221               argp[0] ++;       /* and leave it to be output later.  */
 222               argp[1] ++;       /* Increment the following arg, too!  */
 223               break;
 224
 225             case '%':           /* %% means output %; no arg.  */
 226               goto ordinary;
 227
 228             case 'n':           /* %n means xor each of next two args with 140.  */
 229               argp[0] ^= 0140;
 230               argp[1] ^= 0140;
 231               break;
 232
 233             case 'm':           /* %m means xor each of next two args with 177.  */
 234               argp[0] ^= 0177;
 235               argp[1] ^= 0177;
 236               break;
 237
 238             case 'B':           /* %B means express arg as BCD char code.  */
 239               argp[0] += 6 * (tem / 10);
 240               break;
 241
 242             case 'D':           /* %D means weird Delta Data transformation.  */
 243               argp[0] -= 2 * (tem % 16);
 244               break;
 245
 246             default:
 247               abort ();
 248             }
 249         }
 250       else
 251         /* Ordinary character in the argument string.  */
 252       ordinary:
 253         *op++ = c;
 254     }
 255   *op = 0;
 256   while (doup-- > 0)
 257     strcat (op, up);
 258   while (doleft-- > 0)
 259     strcat (op, left);
 260   return outstring;
 261 }
 262 \f
 263 #ifdef DEBUG
 264
 265 main (argc, argv)
 266      int argc;
 267      char **argv;
 268 {
 269   char buf[50];
 270   int args[3];
 271   args[0] = atoi (argv[2]);
 272   args[1] = atoi (argv[3]);
 273   args[2] = atoi (argv[4]);
 274   tparam1 (argv[1], buf, "LEFT", "UP", args);
 275   printf ("%s\n", buf);
 276   return 0;
 277 }
 278
 279 #endif /* DEBUG */
 280