| 1 | /* |
| 2 | * PostScript Type 1 font file support for Halibut |
| 3 | */ |
| 4 | /* |
| 5 | * Type 1 font file formats are specified by Adobe Technical Note |
| 6 | * #5040: "Supporting Downloadable PostScript Language Fonts". |
| 7 | * Halibut supports hexadecimal format (section 3.1) and IBM PC format |
| 8 | * (section 3.3), commonly called PFA and PFB respectively. |
| 9 | */ |
| 10 | |
| 11 | #include <assert.h> |
| 12 | #include <limits.h> |
| 13 | #include <stdio.h> |
| 14 | #include <stdlib.h> |
| 15 | #include "halibut.h" |
| 16 | #include "paper.h" |
| 17 | |
| 18 | #define PFB_ASCII 1 |
| 19 | #define PFB_BINARY 2 |
| 20 | #define PFB_EOF 3 |
| 21 | |
| 22 | typedef struct t1_font_Tag t1_font; |
| 23 | typedef struct t1_data_Tag t1_data; |
| 24 | |
| 25 | struct t1_font_Tag { |
| 26 | t1_data *data; |
| 27 | size_t length1; |
| 28 | size_t length2; |
| 29 | filepos pos; |
| 30 | }; |
| 31 | |
| 32 | struct t1_data_Tag { |
| 33 | char type; |
| 34 | size_t length; |
| 35 | unsigned char *data; |
| 36 | t1_data *next; |
| 37 | }; |
| 38 | |
| 39 | typedef struct pfstate_Tag { |
| 40 | t1_data *data; |
| 41 | t1_data *curblock; |
| 42 | size_t offset; |
| 43 | } pfstate; |
| 44 | |
| 45 | static void pf_identify(t1_font *tf); |
| 46 | |
| 47 | static t1_data *load_pfb_file(FILE *fp, filepos *pos) { |
| 48 | t1_data *head = NULL, *tail = NULL; |
| 49 | int c, i; |
| 50 | char type; |
| 51 | |
| 52 | pos->line = 0; |
| 53 | for (;;) { |
| 54 | if (fgetc(fp) != 128) abort(); |
| 55 | type = fgetc(fp); |
| 56 | if (type == PFB_EOF) return head; |
| 57 | if (tail) { |
| 58 | tail->next = snew(t1_data); |
| 59 | tail = tail->next; |
| 60 | } else { |
| 61 | head = snew(t1_data); |
| 62 | tail = head; |
| 63 | } |
| 64 | tail->type = type; |
| 65 | tail->length = 0; |
| 66 | for (i = 0; i < 4; i++) { |
| 67 | c = fgetc(fp); |
| 68 | if (c == EOF) abort(); |
| 69 | tail->length |= c << (8 * i); |
| 70 | } |
| 71 | tail->data = snewn(tail->length, unsigned char); |
| 72 | if (fread(tail->data, 1, tail->length, fp) != tail->length) abort(); |
| 73 | } |
| 74 | tail->next = NULL; |
| 75 | } |
| 76 | |
| 77 | static t1_data *load_pfa_file(FILE *fp, filepos *pos) { |
| 78 | t1_data *ret = snew(t1_data); |
| 79 | size_t off = 0, len, got; |
| 80 | |
| 81 | pos->line = 0; |
| 82 | ret->type = PFB_ASCII; |
| 83 | len = 32768; |
| 84 | ret->data = snewn(len, unsigned char); |
| 85 | for (;;) { |
| 86 | got = fread(ret->data + off, 1, len - off, fp); |
| 87 | off += got; |
| 88 | if (off != len) break; |
| 89 | len *= 2; |
| 90 | ret->data = sresize(ret->data, len, unsigned char); |
| 91 | } |
| 92 | ret->data = sresize(ret->data, off, unsigned char); |
| 93 | ret->length = off; |
| 94 | ret->next = NULL; |
| 95 | return ret; |
| 96 | } |
| 97 | |
| 98 | void read_pfa_file(input *in) { |
| 99 | t1_font *tf = snew(t1_font); |
| 100 | |
| 101 | tf->data = load_pfa_file(in->currfp, &in->pos); |
| 102 | tf->pos = in->pos; |
| 103 | tf->length1 = tf->length2 = 0; |
| 104 | fclose(in->currfp); |
| 105 | pf_identify(tf); |
| 106 | } |
| 107 | |
| 108 | void read_pfb_file(input *in) { |
| 109 | t1_font *tf = snew(t1_font); |
| 110 | |
| 111 | tf->data = load_pfb_file(in->currfp, &in->pos); |
| 112 | tf->pos = in->pos; |
| 113 | tf->length1 = tf->length2 = 0; |
| 114 | fclose(in->currfp); |
| 115 | pf_identify(tf); |
| 116 | } |
| 117 | static char *pf_read_token(pfstate *); |
| 118 | |
| 119 | /* |
| 120 | * Read a character from the initial plaintext part of a Type 1 font |
| 121 | */ |
| 122 | static int pf_getc(pfstate *pf) { |
| 123 | if (pf->offset == pf->curblock->length) { |
| 124 | if (pf->curblock->next == NULL) return EOF; |
| 125 | pf->curblock = pf->curblock->next; |
| 126 | pf->offset = 0; |
| 127 | } |
| 128 | if (pf->curblock->type != PFB_ASCII) return EOF; |
| 129 | return pf->curblock->data[pf->offset++]; |
| 130 | } |
| 131 | |
| 132 | static void pf_ungetc(int c, pfstate *pf) { |
| 133 | assert(pf->offset > 0); |
| 134 | pf->offset--; |
| 135 | assert(c == pf->curblock->data[pf->offset]); |
| 136 | } |
| 137 | |
| 138 | static void pf_rewind(pfstate *pf) { |
| 139 | pf->curblock = pf->data; |
| 140 | pf->offset = 0; |
| 141 | } |
| 142 | |
| 143 | static void pf_seek(pfstate *pf, size_t off) { |
| 144 | t1_data *td = pf->data; |
| 145 | |
| 146 | while (td->length < off) { |
| 147 | off -= td->length; |
| 148 | td = td->next; |
| 149 | } |
| 150 | pf->curblock = td; |
| 151 | pf->offset = off; |
| 152 | } |
| 153 | |
| 154 | static size_t pf_tell(pfstate *pf) { |
| 155 | t1_data *td = pf->data; |
| 156 | size_t o = 0; |
| 157 | |
| 158 | while (td != pf->curblock) { |
| 159 | o += td->length; |
| 160 | td = td->next; |
| 161 | } |
| 162 | return o + pf->offset; |
| 163 | } |
| 164 | |
| 165 | static void pf_identify(t1_font *tf) { |
| 166 | rdstringc rsc = { 0, 0, NULL }; |
| 167 | char *p; |
| 168 | size_t len; |
| 169 | char *fontname; |
| 170 | font_info *fi; |
| 171 | int c; |
| 172 | pfstate pfs, *pf = &pfs; |
| 173 | |
| 174 | pf->data = tf->data; |
| 175 | pf_rewind(pf); |
| 176 | do { |
| 177 | c = pf_getc(pf); |
| 178 | if (c == EOF) { |
| 179 | sfree(rsc.text); |
| 180 | err_pfeof(&tf->pos); |
| 181 | return; |
| 182 | } |
| 183 | rdaddc(&rsc, c); |
| 184 | } while (c != 012 && c != 015); |
| 185 | p = rsc.text; |
| 186 | if ((p = strchr(p, ':')) == NULL) { |
| 187 | sfree(rsc.text); |
| 188 | err_pfhead(&tf->pos); |
| 189 | return; |
| 190 | } |
| 191 | p++; |
| 192 | p += strspn(p, " \t"); |
| 193 | len = strcspn(p, " \t"); |
| 194 | fontname = snewn(len + 1, char); |
| 195 | memcpy(fontname, p, len); |
| 196 | fontname[len] = 0; |
| 197 | sfree(rsc.text); |
| 198 | |
| 199 | for (fi = all_fonts; fi; fi = fi->next) { |
| 200 | if (strcmp(fi->name, fontname) == 0) { |
| 201 | fi->fontfile = tf; |
| 202 | fi->filetype = TYPE1; |
| 203 | sfree(fontname); |
| 204 | return; |
| 205 | } |
| 206 | } |
| 207 | err_pfnoafm(&tf->pos, fontname); |
| 208 | sfree(fontname); |
| 209 | } |
| 210 | |
| 211 | /* |
| 212 | * PostScript white space characters; PLRM3 table 3.1 |
| 213 | */ |
| 214 | static int pf_isspace(int c) { |
| 215 | return c == 000 || c == 011 || c == 012 || c == 014 || c == 015 || |
| 216 | c == ' '; |
| 217 | } |
| 218 | |
| 219 | /* |
| 220 | * PostScript special characters; PLRM3 page 27 |
| 221 | */ |
| 222 | static int pf_isspecial(int c) { |
| 223 | return c == '(' || c == ')' || c == '<' || c == '>' || c == '[' || |
| 224 | c == ']' || c == '{' || c == '}' || c == '/' || c == '%'; |
| 225 | } |
| 226 | |
| 227 | static size_t pf_findtoken(t1_font *tf, size_t off, char const *needle) { |
| 228 | char *tok; |
| 229 | pfstate pfs, *pf = &pfs; |
| 230 | |
| 231 | pf->data = tf->data; |
| 232 | pf_seek(pf, off); |
| 233 | for (;;) { |
| 234 | tok = pf_read_token(pf); |
| 235 | if (tok == NULL) { |
| 236 | if (pf->offset == 0 && pf->curblock->type == PFB_BINARY) |
| 237 | pf->curblock = pf->curblock->next; |
| 238 | else |
| 239 | return (size_t)-1; |
| 240 | } else { |
| 241 | if (strcmp(tok, needle) == 0) { |
| 242 | sfree(tok); |
| 243 | return pf_tell(pf); |
| 244 | } |
| 245 | sfree(tok); |
| 246 | } |
| 247 | } |
| 248 | } |
| 249 | |
| 250 | static size_t pf_length1(t1_font *tf) { |
| 251 | size_t ret; |
| 252 | |
| 253 | ret = pf_findtoken(tf, 0, "eexec"); |
| 254 | if (ret == (size_t)-1) { |
| 255 | err_pfeof(&tf->pos); |
| 256 | return 0; |
| 257 | } |
| 258 | return ret; |
| 259 | } |
| 260 | |
| 261 | static size_t pf_length2(t1_font *tf) { |
| 262 | size_t ret; |
| 263 | |
| 264 | if (tf->length1 == 0) |
| 265 | tf->length1 = pf_length1(tf); |
| 266 | ret = pf_findtoken(tf, tf->length1, "cleartomark"); |
| 267 | if (ret == (size_t)-1) { |
| 268 | err_pfeof(&tf->pos); |
| 269 | return 0; |
| 270 | } |
| 271 | return ret - 12 - tf->length1; /* backspace over "cleartomark\n" */ |
| 272 | } |
| 273 | |
| 274 | static void pf_getascii(t1_font *tf, size_t off, size_t len, |
| 275 | char **bufp, size_t *lenp) { |
| 276 | t1_data *td = tf->data; |
| 277 | size_t blk, i; |
| 278 | char *p; |
| 279 | |
| 280 | while (td && off >= td->length) { |
| 281 | off -= td->length; |
| 282 | td = td->next; |
| 283 | } |
| 284 | *bufp = NULL; |
| 285 | *lenp = 0; |
| 286 | while (td && len) { |
| 287 | blk = len < td->length ? len : td->length; |
| 288 | if (td->type == PFB_ASCII) { |
| 289 | *bufp = sresize(*bufp, *lenp + blk, char); |
| 290 | memcpy(*bufp + *lenp, td->data + off, blk); |
| 291 | *lenp += blk; |
| 292 | } else { |
| 293 | *bufp = sresize(*bufp, *lenp + blk * 2 + blk / 39 + 3, char); |
| 294 | p = *bufp + *lenp; |
| 295 | for (i = 0; i < blk; i++) { |
| 296 | if (i % 39 == 0) p += sprintf(p, "\n"); |
| 297 | p += sprintf(p, "%02x", td->data[off + i]); |
| 298 | } |
| 299 | p += sprintf(p, "\n"); |
| 300 | *lenp = p - *bufp; |
| 301 | } |
| 302 | len -= blk; |
| 303 | td = td->next; |
| 304 | off = 0; |
| 305 | } |
| 306 | } |
| 307 | |
| 308 | void pf_writeps(font_info const *fi, FILE *ofp) { |
| 309 | char *buf; |
| 310 | size_t len; |
| 311 | |
| 312 | pf_getascii(fi->fontfile, 0, INT_MAX, &buf, &len); |
| 313 | fwrite(buf, 1, len, ofp); |
| 314 | sfree(buf); |
| 315 | } |
| 316 | |
| 317 | static int hexval(char c) { |
| 318 | if (c >= '0' && c <= '9') return c - '0'; |
| 319 | if (c >= 'A' && c <= 'F') return c - 'A' + 0xA; |
| 320 | if (c >= 'a' && c <= 'f') return c - 'a' + 0xa; |
| 321 | return 0; |
| 322 | } |
| 323 | |
| 324 | static void pf_getbinary(t1_font *tf, size_t off, size_t len, |
| 325 | char **bufp, size_t *lenp) { |
| 326 | t1_data *td = tf->data; |
| 327 | size_t blk, i; |
| 328 | int havenybble = 0; |
| 329 | char *p, nybble; |
| 330 | |
| 331 | while (td && off >= td->length) { |
| 332 | off -= td->length; |
| 333 | td = td->next; |
| 334 | } |
| 335 | *bufp = NULL; |
| 336 | *lenp = 0; |
| 337 | while (td && len) { |
| 338 | blk = len < td->length ? len : td->length; |
| 339 | if (td->type == PFB_BINARY) { |
| 340 | *bufp = sresize(*bufp, *lenp + blk, char); |
| 341 | memcpy(*bufp + *lenp, td->data + off, blk); |
| 342 | *lenp += blk; |
| 343 | } else { |
| 344 | *bufp = sresize(*bufp, *lenp + blk / 2 + 1, char); |
| 345 | p = *bufp + *lenp; |
| 346 | for (i = 0; i < blk; i++) { |
| 347 | if (pf_isspace(td->data[off + i])) continue; |
| 348 | if (!havenybble) |
| 349 | nybble = hexval(td->data[off+i]); |
| 350 | else |
| 351 | *p++ = (nybble << 4) | hexval(td->data[off+i]); |
| 352 | havenybble = !havenybble; |
| 353 | } |
| 354 | *lenp = p - *bufp; |
| 355 | } |
| 356 | len -= blk; |
| 357 | td = td->next; |
| 358 | off = 0; |
| 359 | } |
| 360 | } |
| 361 | |
| 362 | |
| 363 | /* |
| 364 | * Return the initial, unencrypted, part of a font. |
| 365 | */ |
| 366 | void pf_part1(font_info *fi, char **bufp, size_t *lenp) { |
| 367 | t1_font *tf = fi->fontfile; |
| 368 | |
| 369 | if (tf->length1 == 0) |
| 370 | tf->length1 = pf_length1(tf); |
| 371 | pf_getascii(tf, 0, tf->length1, bufp, lenp); |
| 372 | } |
| 373 | |
| 374 | /* |
| 375 | * Return the middle, encrypted, part of a font. |
| 376 | */ |
| 377 | void pf_part2(font_info *fi, char **bufp, size_t *lenp) { |
| 378 | t1_font *tf = fi->fontfile; |
| 379 | |
| 380 | if (tf->length2 == 0) |
| 381 | tf->length2 = pf_length2(tf); |
| 382 | pf_getbinary(tf, tf->length1, tf->length2, bufp, lenp); |
| 383 | if (*lenp >= 256) |
| 384 | *lenp -= 256; |
| 385 | } |
| 386 | |
| 387 | static char *pf_read_litstring(pfstate *pf) { |
| 388 | rdstringc rsc = { 0, 0, NULL }; |
| 389 | int depth = 1; |
| 390 | int c; |
| 391 | |
| 392 | rdaddc(&rsc, '('); |
| 393 | do { |
| 394 | c = pf_getc(pf); |
| 395 | switch (c) { |
| 396 | case '(': |
| 397 | depth++; break; |
| 398 | case ')': |
| 399 | depth--; break; |
| 400 | case '\\': |
| 401 | rdaddc(&rsc, '\\'); |
| 402 | c = pf_getc(pf); |
| 403 | break; |
| 404 | } |
| 405 | if (c != EOF) rdaddc(&rsc, c); |
| 406 | } while (depth > 0 && c != EOF); |
| 407 | return rsc.text; |
| 408 | } |
| 409 | |
| 410 | static char *pf_read_hexstring(pfstate *pf) { |
| 411 | rdstringc rsc = { 0, 0, NULL }; |
| 412 | int c; |
| 413 | |
| 414 | rdaddc(&rsc, '<'); |
| 415 | do { |
| 416 | c = pf_getc(pf); |
| 417 | if (c != EOF) rdaddc(&rsc, c); |
| 418 | } while (c != '>' && c != EOF); |
| 419 | return rsc.text; |
| 420 | } |
| 421 | |
| 422 | static char *pf_read_word(pfstate *pf, int c) { |
| 423 | rdstringc rsc = { 0, 0, NULL }; |
| 424 | |
| 425 | rdaddc(&rsc, c); |
| 426 | if (c == '{' || c == '}' || c == '[' || c == ']') |
| 427 | return rsc.text; |
| 428 | for (;;) { |
| 429 | c = pf_getc(pf); |
| 430 | if (pf_isspecial(c) || pf_isspace(c) || c == EOF) break; |
| 431 | rdaddc(&rsc, c); |
| 432 | } |
| 433 | if (pf_isspecial(c)) pf_ungetc(c, pf); |
| 434 | return rsc.text; |
| 435 | } |
| 436 | |
| 437 | static char *pf_read_token(pfstate *pf) { |
| 438 | int c; |
| 439 | |
| 440 | do { |
| 441 | c = pf_getc(pf); |
| 442 | } while (pf_isspace(c)); |
| 443 | if (c == EOF) return NULL; |
| 444 | if (c == '%') { |
| 445 | do { |
| 446 | c = pf_getc(pf); |
| 447 | } while (c != 012 && c != 015); |
| 448 | return pf_read_token(pf); |
| 449 | } |
| 450 | if (c == '(') return pf_read_litstring(pf); |
| 451 | if (c == '<') return pf_read_hexstring(pf); |
| 452 | return pf_read_word(pf, c); |
| 453 | } |