post.c

   1 /*
   2  * neatpost troff postscript postprocessor
   3  *
   4  * Copyright (C) 2013 Ali Gholami Rudi <ali at rudi dot ir>
   5  *
   6  * This program is released under the Modified BSD license.
   7  */
   8 #include <ctype.h>
   9 #include <stdio.h>
  10 #include <string.h>
  11 #include "post.h"
  12
  13 static int o_pg;
  14
  15 static int next(void)
  16 {
  17         return getc(stdin);
  18 }
  19
  20 static void back(int c)
  21 {
  22         ungetc(c, stdin);
  23 }
  24
  25 static int utf8len(int c)
  26 {
  27         if (c <= 0x7f)
  28                 return 1;
  29         if (c >= 0xfc)
  30                 return 6;
  31         if (c >= 0xf8)
  32                 return 5;
  33         if (c >= 0xf0)
  34                 return 4;
  35         if (c >= 0xe0)
  36                 return 3;
  37         if (c >= 0xc0)
  38                 return 2;
  39         return 1;
  40 }
  41
  42 static int nextutf8(char *s)
  43 {
  44         int c = next();
  45         int l = utf8len(c);
  46         int i;
  47         if (c < 0)
  48                 return 0;
  49         s[0] = c;
  50         for (i = 1; i < l; i++)
  51                 s[i] = next();
  52         s[l] = '\0';
  53         return l;
  54 }
  55
  56 /* skip blanks */
  57 static void nextskip(void)
  58 {
  59         int c;
  60         do {
  61                 c = next();
  62         } while (isspace(c));
  63         back(c);
  64 }
  65
  66 static int nextnum(void)
  67 {
  68         int c;
  69         int n = 0;
  70         int neg = 0;
  71         nextskip();
  72         while (1) {
  73                 c = next();
  74                 if (!n && c == '-') {
  75                         neg = 1;
  76                         continue;
  77                 }
  78                 if (!isdigit(c))
  79                         back(c);
  80                 if (c < 0 || !isdigit(c))
  81                         break;
  82                 n = n * 10 + c - '0';
  83         }
  84         return neg ? -n : n;
  85 }
  86
  87 static int iseol(void)
  88 {
  89         int c;
  90         do {
  91                 c = next();
  92         } while (c == ' ');
  93         back(c);
  94         return c == '\n';
  95 }
  96
  97 /* skip until the end of line */
  98 static void nexteol(void)
  99 {
 100         int c;
 101         do {
 102                 c = next();
 103         } while (c >= 0 && c != '\n');
 104 }
 105
 106 static void nextword(char *s)
 107 {
 108         int c;
 109         nextskip();
 110         c = next();
 111         while (c >= 0 && !isspace(c)) {
 112                 *s++ = c;
 113                 c = next();
 114         }
 115         if (c >= 0)
 116                 back(c);
 117         *s = '\0';
 118 }
 119
 120 /* read until eol */
 121 static void readln(char *s)
 122 {
 123         int c;
 124         c = next();
 125         while (c > 0 && c != '\n') {
 126                 *s++ = c;
 127                 c = next();
 128         }
 129         if (c == '\n')
 130                 back(c);
 131         *s = '\0';
 132 }
 133
 134 static void postspline(int h1, int v1)
 135 {
 136         int h2, v2;
 137         while (!iseol()) {
 138                 h2 = nextnum();
 139                 v2 = nextnum();
 140                 draws(h1, v1, h2, v2);
 141                 h1 = h2;
 142                 v1 = v2;
 143         }
 144         draws(h1, v1, 0, 0);
 145 }
 146
 147 static void postdraw(void)
 148 {
 149         int h1, h2, v1, v2;
 150         int c = next();
 151         drawbeg(NULL);
 152         switch (c) {
 153         case 'l':
 154                 h1 = nextnum();
 155                 v1 = nextnum();
 156                 drawl(h1, v1);
 157                 break;
 158         case 'c':
 159                 drawc(nextnum());
 160                 break;
 161         case 'e':
 162                 h1 = nextnum();
 163                 v1 = nextnum();
 164                 drawe(h1, v1);
 165                 break;
 166         case 'a':
 167                 h1 = nextnum();
 168                 v1 = nextnum();
 169                 h2 = nextnum();
 170                 v2 = nextnum();
 171                 drawa(h1, v1, h2, v2);
 172                 break;
 173         case '~':
 174                 h1 = nextnum();
 175                 v1 = nextnum();
 176                 if (iseol())
 177                         drawl(h1, v1);
 178                 else
 179                         postspline(h1, v1);
 180                 break;
 181         }
 182         drawend(NULL);
 183         nexteol();
 184 }
 185
 186 static void postps(void)
 187 {
 188         char cmd[ILNLEN];
 189         char arg[ILNLEN];
 190         nextword(cmd);
 191         readln(arg);
 192         if (!strcmp("PS", cmd) || !strcmp("ps", cmd))
 193                 out("%s\n", arg);
 194         if (!strcmp("BeginObject", cmd))
 195                 drawbeg(arg);
 196         if (!strcmp("EndObject", cmd))
 197                 drawend(arg);
 198 }
 199
 200 static char devpath[PATHLEN] = "devutf";
 201
 202 static void postx(void)
 203 {
 204         char cmd[128];
 205         char dev[128];
 206         int pos;
 207         nextword(cmd);
 208         switch (cmd[0]) {
 209         case 'f':
 210                 pos = nextnum();
 211                 nextword(dev);
 212                 dev_mnt(pos, dev, dev);
 213                 outmnt(pos);
 214                 break;
 215         case 'i':
 216                 dev_open(devpath);
 217                 break;
 218         case 'T':
 219                 nextword(dev);
 220                 sprintf(devpath, "%s/font/dev%s", TROFFROOT, dev);
 221                 break;
 222         case 's':
 223                 break;
 224         case 'X':
 225                 postps();
 226                 break;
 227         }
 228         nexteol();
 229 }
 230
 231 static void postcmd(int c)
 232 {
 233         char cs[GNLEN];
 234         if (isdigit(c)) {
 235                 outrel((c - '0') * 10 + next() - '0', 0);
 236                 nextutf8(cs);
 237                 outc(cs);
 238                 return;
 239         }
 240         switch (c) {
 241         case 's':
 242                 outsize(nextnum());
 243                 break;
 244         case 'f':
 245                 outfont(nextnum());
 246                 break;
 247         case 'H':
 248                 outh(nextnum());
 249                 break;
 250         case 'V':
 251                 outv(nextnum());
 252                 break;
 253         case 'h':
 254                 outrel(nextnum(), 0);
 255                 break;
 256         case 'v':
 257                 outrel(0, nextnum());
 258                 break;
 259         case 'c':
 260                 nextutf8(cs);
 261                 outc(cs);
 262                 break;
 263         case 'm':
 264                 nextword(cs);
 265                 outcolor(clr_get(cs));
 266                 break;
 267         case 'N':
 268                 nextnum();
 269                 break;
 270         case 'C':
 271                 nextword(cs);
 272                 outc(cs);
 273                 break;
 274         case 'p':
 275                 if (o_pg)
 276                         ps_pageend(o_pg);
 277                 o_pg = nextnum();
 278                 ps_pagebeg(o_pg);
 279                 outpage();
 280                 break;
 281         case 'w':
 282                 break;
 283         case 'n':
 284                 nextnum();
 285                 nextnum();
 286                 break;
 287         case 'D':
 288                 postdraw();
 289                 break;
 290         case 'x':
 291                 postx();
 292                 break;
 293         case '#':
 294                 nexteol();
 295                 break;
 296         default:
 297                 fprintf(stderr, "unknown command: %c\n", c);
 298         }
 299 }
 300
 301 static void post(void)
 302 {
 303         int c;
 304         while ((c = next()) >= 0)
 305                 if (!isspace(c))
 306                         postcmd(c);
 307         if (o_pg)
 308                 ps_pageend(o_pg);
 309 }
 310
 311 int main(void)
 312 {
 313         ps_header();
 314         post();
 315         ps_trailer(o_pg, o_fonts);
 316         return 0;
 317 }