mdw@git.distorted.org.uk Git - sgt/halibut/blob - bk_pdf.c

   1 /*
   2  * PDF backend for Halibut
   3  */
   4
   5 #include <assert.h>
   6 #include "halibut.h"
   7 #include "paper.h"
   8 #include "deflate.h"
   9
  10 #define TREE_BRANCH 8                  /* max branching factor in page tree */
  11
  12 paragraph *pdf_config_filename(char *filename)
  13 {
  14     return cmdline_cfg_simple("pdf-filename", filename, NULL);
  15 }
  16
  17 struct object_Tag {
  18     objlist *list;
  19     object *next;
  20     int number;
  21     rdstringc main, stream;
  22     int size, fileoff;
  23     char *final;
  24 };
  25
  26 struct objlist_Tag {
  27     int number;
  28     object *head, *tail;
  29 };
  30
  31 static void pdf_string(void (*add)(object *, char const *),
  32                        object *, char const *);
  33 static void pdf_string_len(void (*add)(object *, char const *),
  34                            object *, char const *, int);
  35 static void objref(object *o, object *dest);
  36 static void objdest(object *o, page_data *p);
  37
  38 static int is_std_font(char const *name);
  39
  40 static void make_pages_node(object *node, object *parent, page_data *first,
  41                             page_data *last, object *resources,
  42                             object *mediabox);
  43 static int make_outline(object *parent, outline_element *start, int n,
  44                         int open);
  45 static int pdf_versionid(FILE *fp, word *words);
  46
  47 void pdf_backend(paragraph *sourceform, keywordlist *keywords,
  48                  indexdata *idx, void *vdoc) {
  49     document *doc = (document *)vdoc;
  50     int font_index;
  51     font_encoding *fe;
  52     page_data *page;
  53     int pageno;
  54     FILE *fp;
  55     char *filename;
  56     paragraph *p;
  57     objlist olist;
  58     object *o, *info, *cat, *outlines, *pages, *resources, *mediabox;
  59     int fileoff;
  60
  61     IGNORE(keywords);
  62     IGNORE(idx);
  63
  64     filename = dupstr("output.pdf");
  65     for (p = sourceform; p; p = p->next) {
  66         if (p->type == para_Config) {
  67             if (!ustricmp(p->keyword, L"pdf-filename")) {
  68                 sfree(filename);
  69                 filename = dupstr(adv(p->origkeyword));
  70             }
  71         }
  72     }
  73
  74     olist.head = olist.tail = NULL;
  75     olist.number = 1;
  76
  77     {
  78         char buf[256];
  79
  80         info = new_object(&olist);
  81         objtext(info, "<<\n");
  82         if (doc->n_outline_elements > 0) {
  83             char *title;
  84             int titlelen;
  85
  86             title =
  87                pdf_outline_convert(doc->outline_elements->pdata->outline_title,
  88                                         &titlelen);
  89             objtext(info, "/Title ");
  90             pdf_string_len(objtext, info, title, titlelen);
  91             sfree(title);
  92             objtext(info, "\n");
  93         }
  94         objtext(info, "/Producer ");
  95         sprintf(buf, "Halibut, %s", version);
  96         pdf_string(objtext, info, buf);
  97         objtext(info, "\n>>\n");
  98     }
  99
 100     cat = new_object(&olist);
 101     if (doc->n_outline_elements > 0)
 102         outlines = new_object(&olist);
 103     else
 104         outlines = NULL;
 105     pages = new_object(&olist);
 106     resources = new_object(&olist);
 107
 108     /*
 109      * The catalogue just contains references to the outlines and
 110      * pages objects, and the pagelabels dictionary.
 111      */
 112     objtext(cat, "<<\n/Type /Catalog");
 113     if (outlines) {
 114         objtext(cat, "\n/Outlines ");
 115         objref(cat, outlines);
 116     }
 117     objtext(cat, "\n/Pages ");
 118     objref(cat, pages);
 119     /* Halibut just numbers pages 1, 2, 3, ... */
 120     objtext(cat, "\n/PageLabels<</Nums[0<</S/D>>]>>");
 121     if (outlines)
 122         objtext(cat, "\n/PageMode /UseOutlines");
 123     objtext(cat, "\n>>\n");
 124
 125     /*
 126      * Set up the resources dictionary, which mostly means
 127      * providing all the font objects and names to call them by.
 128      */
 129     font_index = 0;
 130     objtext(resources, "<<\n/ProcSet [/PDF/Text]\n/Font <<\n");
 131     for (fe = doc->fonts->head; fe; fe = fe->next) {
 132         char fname[40];
 133         char buf[80];
 134         int i, prev;
 135         object *font, *fontdesc;
 136         int flags;
 137         font_info const *fi = fe->font->info;
 138
 139         sprintf(fname, "f%d", font_index++);
 140         fe->name = dupstr(fname);
 141
 142         font = new_object(&olist);
 143
 144         objtext(resources, "/");
 145         objtext(resources, fe->name);
 146         objtext(resources, " ");
 147         objref(resources, font);
 148         objtext(resources, "\n");
 149
 150
 151         /*
 152          * Construct those parts of the font descriptor that don't dependd
 153          * on the file format.
 154          */
 155         if (!is_std_font(fe->font->info->name)) {
 156             fontdesc = new_object(&olist);
 157
 158 #define FF_FIXEDPITCH   0x00000001
 159 #define FF_SERIF        0x00000002
 160 #define FF_SYMBOLIC     0x00000004
 161 #define FF_SCRIPT       0x00000008
 162 #define FF_NONSYMBOLIC  0x00000020
 163 #define FF_ITALIC       0x00000040
 164 #define FF_ALLCAP       0x00010000
 165 #define FF_SMALLCAP     0x00020000
 166 #define FF_FORCEBOLD    0x00040000
 167
 168             objtext(fontdesc, "<<\n/Type /FontDescriptor\n/Name /");
 169             objtext(fontdesc, fi->name);
 170             flags = 0;
 171             if (fi->italicangle) flags |= FF_ITALIC;
 172             flags |= FF_NONSYMBOLIC;
 173             sprintf(buf, "\n/Flags %d\n", flags);
 174             objtext(fontdesc, buf);
 175             sprintf(buf, "/FontBBox [%g %g %g %g]\n", fi->fontbbox[0],
 176                     fi->fontbbox[1], fi->fontbbox[2], fi->fontbbox[3]);
 177             objtext(fontdesc, buf);
 178             sprintf(buf, "/ItalicAngle %g\n", fi->italicangle);
 179             objtext(fontdesc, buf);
 180             sprintf(buf, "/Ascent %g\n", fi->ascent);
 181             objtext(fontdesc, buf);
 182             sprintf(buf, "/Descent %g\n", fi->descent);
 183             objtext(fontdesc, buf);
 184             sprintf(buf, "/CapHeight %g\n", fi->capheight);
 185             objtext(fontdesc, buf);
 186             sprintf(buf, "/XHeight %g\n", fi->xheight);
 187             objtext(fontdesc, buf);
 188             sprintf(buf, "/StemH %g\n", fi->stemh);
 189             objtext(fontdesc, buf);
 190             sprintf(buf, "/StemV %g\n", fi->stemv);
 191             objtext(fontdesc, buf);
 192         }
 193
 194         objtext(font, "<<\n/Type /Font\n/BaseFont /");
 195         objtext(font, fe->font->info->name);
 196         if (fe->font->info->filetype == TRUETYPE) {
 197             object *cidfont = new_object(&olist);
 198             object *cmap = new_object(&olist);
 199             objtext(font, "/Subtype/Type0\n/Encoding ");
 200             sfnt_cmap(fe, cmap);
 201             objref(font, cmap);
 202             objtext(font, "\n/DescendantFonts[");
 203             objref(font, cidfont);
 204             objtext(font, "]\n");
 205             objtext(cidfont, "<<\n/Type/Font\n/Subtype/CIDFontType2\n"
 206                     "/BaseFont/");
 207             objtext(cidfont, fe->font->info->name);
 208             objtext(cidfont, "\n/CIDSystemInfo<</Registry(Adobe)"
 209                     "/Ordering(Identity)/Supplement 0>>\n");
 210             objtext(cidfont, "/FontDescriptor ");
 211             objref(cidfont, fontdesc);
 212             objtext(cidfont, "\n/W[0[");
 213             for (i = 0; i < sfnt_nglyphs(fe->font->info->fontfile); i++) {
 214                 char buf[20];
 215                 double width;
 216                 width = find_width(fe->font,
 217                                sfnt_indextoglyph(fe->font->info->fontfile, i));
 218                 sprintf(buf, "%g ", 1000.0 * width / FUNITS_PER_PT);
 219                 objtext(cidfont, buf);
 220             }
 221             objtext(cidfont, "]]>>\n");
 222         } else {
 223             objtext(font, "/Subtype /Type1\n");
 224             objtext(font, "\n/Encoding <<\n/Type /Encoding\n/Differences [");
 225
 226             for (i = 0; i < 256; i++) {
 227                 char buf[20];
 228                 if (fe->vector[i] == NOGLYPH)
 229                     continue;
 230                 if (i != prev + 1) {
 231                     sprintf(buf, "\n%d", i);
 232                     objtext(font, buf);
 233                 }
 234                 objtext(font, i % 8 ? "/" : "\n/");
 235                 objtext(font, glyph_extern(fe->vector[i]));
 236                 prev = i;
 237             }
 238
 239             objtext(font, "\n]\n>>\n");
 240             if (!is_std_font(fe->font->info->name)){
 241                 object *widths = new_object(&olist);
 242                 int firstchar = -1, lastchar = -1;
 243                 for (i = 0; i < 256; i++)
 244                     if (fe->vector[i] != NOGLYPH) {
 245                         if (firstchar < 0) firstchar = i;
 246                         lastchar = i;
 247                     }
 248                 sprintf(buf, "/FirstChar %d\n/LastChar %d\n/Widths ",
 249                         firstchar, lastchar);
 250                 objtext(font, buf);
 251                 objref(font, widths);
 252                 objtext(font, "\n");
 253                 objtext(widths, "[\n");
 254                 for (i = firstchar; i <= lastchar; i++) {
 255                     double width;
 256                     if (fe->vector[i] == NOGLYPH)
 257                         width = 0.0;
 258                     else
 259                         width = find_width(fe->font, fe->vector[i]);
 260                     sprintf(buf, "%g\n", 1000.0 * width / FUNITS_PER_PT);
 261                     objtext(widths, buf);
 262                 }
 263                 objtext(widths, "]\n");
 264                 objtext(font, "/FontDescriptor ");
 265                 objref(font, fontdesc);
 266             }
 267
 268         }
 269
 270         if (!is_std_font(fe->font->info->name)) {
 271             if (fi->fontfile && fi->filetype == TYPE1) {
 272                 object *fontfile = new_object(&olist);
 273                 size_t len;
 274                 char *ffbuf;
 275
 276                 pf_part1((font_info *)fi, &ffbuf, &len);
 277                 objstream_len(fontfile, ffbuf, len);
 278                 sfree(ffbuf);
 279                 sprintf(buf, "<<\n/Length1 %lu\n", (unsigned long)len);
 280                 objtext(fontfile, buf);
 281                 pf_part2((font_info *)fi, &ffbuf, &len);
 282                 objstream_len(fontfile, ffbuf, len);
 283                 sfree(ffbuf);
 284                 sprintf(buf, "/Length2 %lu\n", (unsigned long)len);
 285                 objtext(fontfile, buf);
 286                 objtext(fontfile, "/Length3 0\n");
 287                 objtext(fontdesc, "/FontFile ");
 288                 objref(fontdesc, fontfile);
 289             } else if (fi->fontfile && fi->filetype == TRUETYPE) {
 290                 object *fontfile = new_object(&olist);
 291                 size_t len;
 292                 char *ffbuf;
 293
 294                 sfnt_data((font_info *)fi, &ffbuf, &len);
 295                 objstream_len(fontfile, ffbuf, len);
 296                 sprintf(buf, "<<\n/Length1 %lu\n", (unsigned long)len);
 297                 objtext(fontfile, buf);
 298                 objtext(fontdesc, "/FontFile2 ");
 299                 objref(fontdesc, fontfile);
 300             }
 301             objtext(fontdesc, "\n>>\n");
 302         }
 303
 304         objtext(font, "\n>>\n");
 305     }
 306     objtext(resources, ">>\n>>\n");
 307
 308     {
 309         char buf[255];
 310         mediabox = new_object(&olist);
 311         sprintf(buf, "[0 0 %g %g]\n",
 312                 doc->paper_width / FUNITS_PER_PT,
 313                 doc->paper_height / FUNITS_PER_PT);
 314         objtext(mediabox, buf);
 315     }
 316
 317     /*
 318      * Define the page objects for each page, and get each one
 319      * ready to have a `Parent' specification added to it.
 320      */
 321     for (page = doc->pages; page; page = page->next) {
 322         object *opage;
 323
 324         opage = new_object(&olist);
 325         page->spare = opage;
 326         objtext(opage, "<<\n/Type /Page\n");
 327     }
 328
 329     /*
 330      * Recursively build the page tree.
 331      */
 332     make_pages_node(pages, NULL, doc->pages, NULL, resources, mediabox);
 333
 334     /*
 335      * Create and render the individual pages.
 336      */
 337     pageno = 0;
 338     for (page = doc->pages; page; page = page->next) {
 339         object *opage, *cstr;
 340         rect *r;
 341         text_fragment *frag, *frag_end;
 342         char buf[256];
 343         int x, y, lx, ly;
 344
 345         opage = (object *)page->spare;
 346         /*
 347          * At this point the page dictionary is already
 348          * half-written, with /Type and /Parent already present. We
 349          * continue from there.
 350          */
 351
 352         /*
 353          * The PDF spec says /Resources is required, but also says
 354          * that it's inheritable and may be omitted if it's present
 355          * in a Pages node. In our case it is: it's present in the
 356          * topmost /Pages node because we carefully put it there.
 357          * So we don't need a /Resources entry here.  The same applies
 358          * to /MediaBox.
 359          */
 360
 361         /*
 362          * Now we're ready to define a content stream containing
 363          * the actual text on the page.
 364          */
 365         cstr = new_object(&olist);
 366         objtext(opage, "/Contents ");
 367         objref(opage, cstr);
 368         objtext(opage, "\n");
 369
 370         /*
 371          * Render any rectangles on the page.
 372          */
 373         for (r = page->first_rect; r; r = r->next) {
 374             char buf[512];
 375             sprintf(buf, "%g %g %g %g re f\n",
 376                     r->x / FUNITS_PER_PT, r->y / FUNITS_PER_PT,
 377                     r->w / FUNITS_PER_PT, r->h / FUNITS_PER_PT);
 378             objstream(cstr, buf);
 379         }
 380
 381         objstream(cstr, "BT\n");
 382
 383         /*
 384          * PDF tracks two separate current positions: the position
 385          * given in the `line matrix' and the position given in the
 386          * `text matrix'. We must therefore track both as well.
 387          * They start off at -1 (unset).
 388          */
 389         lx = ly = -1;
 390         x = y = -1;
 391
 392         frag = page->first_text;
 393         while (frag) {
 394             /*
 395              * For compactness, I'm going to group text fragments
 396              * into subsequences that use the same font+size. So
 397              * first find the end of this subsequence.
 398              */
 399             for (frag_end = frag;
 400                  (frag_end &&
 401                   frag_end->fe == frag->fe &&
 402                   frag_end->fontsize == frag->fontsize);
 403                  frag_end = frag_end->next);
 404
 405             /*
 406              * Now select the text fragment, and prepare to display
 407              * the text.
 408              */
 409             objstream(cstr, "/");
 410             objstream(cstr, frag->fe->name);
 411             sprintf(buf, " %d Tf ", frag->fontsize);
 412             objstream(cstr, buf);
 413
 414             while (frag && frag != frag_end) {
 415                 /*
 416                  * Place the text position for the first piece of
 417                  * text.
 418                  */
 419                 if (lx < 0) {
 420                     sprintf(buf, "1 0 0 1 %g %g Tm ",
 421                             frag->x/FUNITS_PER_PT, frag->y/FUNITS_PER_PT);
 422                 } else {
 423                     sprintf(buf, "%g %g Td ",
 424                             (frag->x - lx)/FUNITS_PER_PT,
 425                             (frag->y - ly)/FUNITS_PER_PT);
 426                 }
 427                 objstream(cstr, buf);
 428                 lx = x = frag->x;
 429                 ly = y = frag->y;
 430
 431                 /*
 432                  * See if we're going to use Tj (show a single
 433                  * string) or TJ (show an array of strings with
 434                  * x-spacings between them). We determine this by
 435                  * seeing if there's more than one text fragment in
 436                  * sequence with the same y-coordinate.
 437                  */
 438                 if (frag->next && frag->next != frag_end &&
 439                     frag->next->y == y) {
 440                     /*
 441                      * The TJ strategy.
 442                      */
 443                     objstream(cstr, "[");
 444                     while (frag && frag != frag_end && frag->y == y) {
 445                         if (frag->x != x) {
 446                             sprintf(buf, "%g",
 447                                     (x - frag->x) * 1000.0 /
 448                                     (FUNITS_PER_PT * frag->fontsize));
 449                             objstream(cstr, buf);
 450                         }
 451                         pdf_string(objstream, cstr, frag->text);
 452                         x = frag->x + frag->width;
 453                         frag = frag->next;
 454                     }
 455                     objstream(cstr, "]TJ\n");
 456                 } else
 457                 {
 458                     /*
 459                      * The Tj strategy.
 460                      */
 461                     pdf_string(objstream, cstr, frag->text);
 462                     objstream(cstr, "Tj\n");
 463                     frag = frag->next;
 464                 }
 465             }
 466         }
 467         objstream(cstr, "ET");
 468
 469         /*
 470          * Also, we want an annotation dictionary containing the
 471          * cross-references from this page.
 472          */
 473         if (page->first_xref) {
 474             xref *xr;
 475             objtext(opage, "/Annots [\n");
 476
 477             for (xr = page->first_xref; xr; xr = xr->next) {
 478                 char buf[256];
 479
 480                 objtext(opage, "<</Subtype/Link\n/Rect[");
 481                 sprintf(buf, "%g %g %g %g",
 482                         xr->lx / FUNITS_PER_PT, xr->by / FUNITS_PER_PT,
 483                         xr->rx / FUNITS_PER_PT, xr->ty / FUNITS_PER_PT);
 484                 objtext(opage, buf);
 485                 objtext(opage, "]/Border[0 0 0]\n");
 486
 487                 if (xr->dest.type == PAGE) {
 488                     objtext(opage, "/Dest");
 489                     objdest(opage, xr->dest.page);
 490                 } else {
 491                     objtext(opage, "/A<</S/URI/URI");
 492                     pdf_string(objtext, opage, xr->dest.url);
 493                     objtext(opage, ">>");
 494                 }
 495
 496                 objtext(opage, ">>\n");
 497             }
 498
 499             objtext(opage, "]\n");
 500         }
 501
 502         objtext(opage, ">>\n");
 503     }
 504
 505     /*
 506      * Set up the outlines dictionary.
 507      */
 508     if (outlines) {
 509         int topcount;
 510         char buf[80];
 511
 512         objtext(outlines, "<<\n/Type /Outlines\n");
 513         topcount = make_outline(outlines, doc->outline_elements,
 514                                 doc->n_outline_elements, TRUE);
 515         sprintf(buf, "/Count %d\n>>\n", topcount);
 516         objtext(outlines, buf);
 517     }
 518
 519     /*
 520      * Assemble the final linear form of every object.
 521      */
 522     for (o = olist.head; o; o = o->next) {
 523         rdstringc rs = {0, 0, NULL};
 524         char text[80];
 525         deflate_compress_ctx *zcontext;
 526         void *zbuf;
 527         int zlen;
 528
 529         sprintf(text, "%d 0 obj\n", o->number);
 530         rdaddsc(&rs, text);
 531
 532         if (o->stream.text) {
 533             if (!o->main.text)
 534                 rdaddsc(&o->main, "<<\n");
 535 #ifdef PDF_NOCOMPRESS
 536             zlen = o->stream.pos;
 537             zbuf = snewn(zlen, char);
 538             memcpy(zbuf, o->stream.text, zlen);
 539             sprintf(text, "/Length %d\n>>\n", zlen);
 540 #else
 541             zcontext = deflate_compress_new(DEFLATE_TYPE_ZLIB);
 542             deflate_compress_data(zcontext, o->stream.text, o->stream.pos,
 543                                   DEFLATE_END_OF_DATA, &zbuf, &zlen);
 544             deflate_compress_free(zcontext);
 545             sprintf(text, "/Filter/FlateDecode\n/Length %d\n>>\n", zlen);
 546 #endif
 547             rdaddsc(&o->main, text);
 548         }
 549
 550         assert(o->main.text);
 551         rdaddsc(&rs, o->main.text);
 552         sfree(o->main.text);
 553
 554         if (rs.text[rs.pos-1] != '\n')
 555             rdaddc(&rs, '\n');
 556
 557         if (o->stream.text) {
 558             rdaddsc(&rs, "stream\n");
 559             rdaddsn(&rs, zbuf, zlen);
 560             rdaddsc(&rs, "\nendstream\n");
 561             sfree(o->stream.text);
 562             sfree(zbuf);
 563         }
 564
 565         rdaddsc(&rs, "endobj\n");
 566
 567         o->final = rs.text;
 568         o->size = rs.pos;
 569     }
 570
 571     /*
 572      * Write out the PDF file.
 573      */
 574
 575     fp = fopen(filename, "wb");
 576     if (!fp) {
 577         error(err_cantopenw, filename);
 578         return;
 579     }
 580
 581     /*
 582      * Header. I'm going to put the version IDs in the header as
 583      * well, simply in PDF comments.  The PDF Reference also suggests
 584      * that binary PDF files contain four top-bit-set characters in
 585      * the second line.
 586      */
 587     fileoff = fprintf(fp, "%%PDF-1.3\n%% L\xc3\xba\xc3\xb0""a\n");
 588     for (p = sourceform; p; p = p->next)
 589         if (p->type == para_VersionID)
 590             fileoff += pdf_versionid(fp, p->words);
 591
 592     /*
 593      * Body
 594      */
 595     for (o = olist.head; o; o = o->next) {
 596         o->fileoff = fileoff;
 597         fwrite(o->final, 1, o->size, fp);
 598         fileoff += o->size;
 599     }
 600
 601     /*
 602      * Cross-reference table
 603      */
 604     fprintf(fp, "xref\n");
 605     assert(olist.head->number == 1);
 606     fprintf(fp, "0 %d\n", olist.tail->number + 1);
 607     fprintf(fp, "0000000000 65535 f \n");
 608     for (o = olist.head; o; o = o->next) {
 609         char entry[40];
 610         sprintf(entry, "%010d 00000 n \n", o->fileoff);
 611         assert(strlen(entry) == 20);
 612         fputs(entry, fp);
 613     }
 614
 615     /*
 616      * Trailer
 617      */
 618     fprintf(fp, "trailer\n<<\n/Size %d\n/Root %d 0 R\n/Info %d 0 R\n>>\n",
 619             olist.tail->number + 1, cat->number, info->number);
 620     fprintf(fp, "startxref\n%d\n%%%%EOF\n", fileoff);
 621
 622     fclose(fp);
 623
 624     sfree(filename);
 625 }
 626
 627 object *new_object(objlist *list)
 628 {
 629     object *obj = snew(object);
 630
 631     obj->list = list;
 632
 633     obj->main.text = NULL;
 634     obj->main.pos = obj->main.size = 0;
 635     obj->stream.text = NULL;
 636     obj->stream.pos = obj->stream.size = 0;
 637
 638     obj->number = list->number++;
 639
 640     obj->next = NULL;
 641     if (list->tail)
 642         list->tail->next = obj;
 643     else
 644         list->head = obj;
 645     list->tail = obj;
 646
 647     obj->size = 0;
 648     obj->final = NULL;
 649
 650     return obj;
 651 }
 652
 653 void objtext(object *o, char const *text)
 654 {
 655     rdaddsc(&o->main, text);
 656 }
 657
 658 void objstream_len(object *o, char const *text, size_t len)
 659 {
 660     rdaddsn(&o->stream, text, len);
 661 }
 662
 663 void objstream(object *o, char const *text)
 664 {
 665     rdaddsc(&o->stream, text);
 666 }
 667
 668 static void objref(object *o, object *dest)
 669 {
 670     char buf[40];
 671     sprintf(buf, "%d 0 R", dest->number);
 672     rdaddsc(&o->main, buf);
 673 }
 674
 675 static void objdest(object *o, page_data *p) {
 676     objtext(o, "[");
 677     objref(o, (object *)p->spare);
 678     objtext(o, "/XYZ null null null]");
 679 }
 680
 681 static char const * const stdfonts[] = {
 682     "Times-Roman", "Times-Bold", "Times-Italic", "Times-BoldItalic",
 683     "Helvetica", "Helvetica-Bold", "Helvetica-Oblique","Helvetica-BoldOblique",
 684     "Courier", "Courier-Bold", "Courier-Oblique", "Courier-BoldOblique",
 685     "Symbol", "ZapfDingbats"
 686 };
 687
 688 static int is_std_font(char const *name) {
 689     unsigned i;
 690     for (i = 0; i < lenof(stdfonts); i++)
 691         if (strcmp(name, stdfonts[i]) == 0)
 692             return TRUE;
 693     return FALSE;
 694 }
 695
 696 static void make_pages_node(object *node, object *parent, page_data *first,
 697                             page_data *last, object *resources,
 698                             object *mediabox)
 699 {
 700     int count;
 701     page_data *page;
 702     char buf[80];
 703
 704     objtext(node, "<<\n/Type /Pages\n");
 705     if (parent) {
 706         objtext(node, "/Parent ");
 707         objref(node, parent);
 708         objtext(node, "\n");
 709     }
 710
 711     /*
 712      * Count the pages in this stretch, to see if there are few
 713      * enough to reference directly.
 714      */
 715     count = 0;
 716     for (page = first; page; page = page->next) {
 717         count++;
 718         if (page == last)
 719             break;
 720     }
 721
 722     sprintf(buf, "/Count %d\n/Kids [\n", count);
 723     objtext(node, buf);
 724
 725     if (count > TREE_BRANCH) {
 726         int i;
 727         page_data *thisfirst, *thislast;
 728
 729         page = first;
 730
 731         for (i = 0; i < TREE_BRANCH; i++) {
 732             int number = (i+1) * count / TREE_BRANCH - i * count / TREE_BRANCH;
 733             thisfirst = page;
 734             while (number--) {
 735                 thislast = page;
 736                 page = page->next;
 737             }
 738
 739             if (thisfirst == thislast) {
 740                 objref(node, (object *)thisfirst->spare);
 741                 objtext((object *)thisfirst->spare, "/Parent ");
 742                 objref((object *)thisfirst->spare, node);
 743                 objtext((object *)thisfirst->spare, "\n");
 744             } else {
 745                 object *newnode = new_object(node->list);
 746                 make_pages_node(newnode, node, thisfirst, thislast,
 747                                 NULL, NULL);
 748                 objref(node, newnode);
 749             }
 750             objtext(node, "\n");
 751         }
 752
 753         assert(thislast == last || page == NULL);
 754
 755     } else {
 756         for (page = first; page; page = page->next) {
 757             objref(node, (object *)page->spare);
 758             objtext(node, "\n");
 759             objtext((object *)page->spare, "/Parent ");
 760             objref((object *)page->spare, node);
 761             objtext((object *)page->spare, "\n");
 762             if (page == last)
 763                 break;
 764         }
 765     }
 766
 767     objtext(node, "]\n");
 768
 769     if (resources) {
 770         objtext(node, "/Resources ");
 771         objref(node, resources);
 772         objtext(node, "\n");
 773     }
 774     if (mediabox) {
 775         objtext(node, "/MediaBox ");
 776         objref(node, mediabox);
 777         objtext(node, "\n");
 778     }
 779
 780     objtext(node, ">>\n");
 781 }
 782
 783 /*
 784  * In text on the page, PDF uses the PostScript font model, which
 785  * means that glyphs are identified by PS strings and hence font
 786  * encoding can be managed independently of the supplied encoding
 787  * of the font. However, in the document outline, the PDF spec
 788  * encodes in either PDFDocEncoding (a custom superset of
 789  * ISO-8859-1) or UTF-16BE.
 790  */
 791 char *pdf_outline_convert(wchar_t *s, int *len) {
 792     char *ret;
 793
 794     ret = utoa_careful_dup(s, CS_PDF);
 795
 796     /*
 797      * Very silly special case: if the returned string begins with
 798      * FE FF, then the PDF reader will mistake it for a UTF-16BE
 799      * string. So in this case we give up on PDFDocEncoding and
 800      * encode it in UTF-16 straight away.
 801      */
 802     if (ret && ret[0] == '\xFE' && ret[1] == '\xFF') {
 803         sfree(ret);
 804         ret = NULL;
 805     }
 806
 807     if (!ret) {
 808         ret = utoa_dup_len(s, CS_UTF16BE, len);
 809     } else {
 810         *len = strlen(ret);
 811     }
 812
 813     return ret;
 814 }
 815
 816 static int make_outline(object *parent, outline_element *items, int n,
 817                         int open)
 818 {
 819     int level, totalcount = 0;
 820     outline_element *itemp;
 821     object *curr, *prev = NULL, *first = NULL, *last = NULL;
 822
 823     assert(n > 0);
 824
 825     level = items->level;
 826
 827     while (n > 0) {
 828         char *title;
 829         int titlelen;
 830
 831         /*
 832          * Here we expect to be sitting on an item at the given
 833          * level. So we start by constructing an outline entry for
 834          * that item.
 835          */
 836         assert(items->level == level);
 837
 838         title = pdf_outline_convert(items->pdata->outline_title, &titlelen);
 839
 840         totalcount++;
 841         curr = new_object(parent->list);
 842         if (!first) first = curr;
 843         last = curr;
 844         objtext(curr, "<<\n/Title ");
 845         pdf_string_len(objtext, curr, title, titlelen);
 846         sfree(title);
 847         objtext(curr, "\n/Parent ");
 848         objref(curr, parent);
 849         objtext(curr, "\n/Dest");
 850         objdest(curr, items->pdata->first->page);
 851         objtext(curr, "\n");
 852         if (prev) {
 853             objtext(curr, "/Prev ");
 854             objref(curr, prev);
 855             objtext(curr, "\n");
 856
 857             objtext(prev, "/Next ");
 858             objref(prev, curr);
 859             objtext(prev, "\n>>\n");
 860         }
 861         prev = curr;
 862
 863         items++, n--;
 864         for (itemp = items; itemp < items+n && itemp->level > level;
 865              itemp++);
 866
 867         if (itemp > items) {
 868             char buf[80];
 869             int count = make_outline(curr, items, itemp - items, FALSE);
 870             if (!open)
 871                 count = -count;
 872             else
 873                 totalcount += count;
 874             sprintf(buf, "/Count %d\n", count);
 875             objtext(curr, buf);
 876         }
 877
 878         n -= itemp - items;
 879         items = itemp;
 880     }
 881     objtext(prev, ">>\n");
 882
 883     assert(first && last);
 884     objtext(parent, "/First ");
 885     objref(parent, first);
 886     objtext(parent, "\n/Last ");
 887     objref(parent, last);
 888     objtext(parent, "\n");
 889
 890     return totalcount;
 891 }
 892
 893 static int pdf_versionid(FILE *fp, word *words)
 894 {
 895     int ret;
 896
 897     ret = fprintf(fp, "%% ");
 898
 899     for (; words; words = words->next) {
 900         char *text;
 901         int type;
 902
 903         switch (words->type) {
 904           case word_HyperLink:
 905           case word_HyperEnd:
 906           case word_UpperXref:
 907           case word_LowerXref:
 908           case word_XrefEnd:
 909           case word_IndexRef:
 910             continue;
 911         }
 912
 913         type = removeattr(words->type);
 914
 915         switch (type) {
 916           case word_Normal:
 917             text = utoa_dup(words->text, CS_ASCII);
 918             break;
 919           case word_WhiteSpace:
 920             text = dupstr(" ");
 921             break;
 922           case word_Quote:
 923             text = dupstr("'");
 924             break;
 925         }
 926
 927         fputs(text, fp);
 928         ret += strlen(text);
 929         sfree(text);
 930     }
 931
 932     ret += fprintf(fp, "\n");
 933
 934     return ret;
 935 }
 936
 937 static void pdf_string_len(void (*add)(object *, char const *),
 938                            object *o, char const *str, int len)
 939 {
 940     char const *p;
 941
 942     add(o, "(");
 943     for (p = str; len > 0; p++, len--) {
 944         char c[10];
 945         if (*p < ' ' || *p > '~') {
 946             sprintf(c, "\\%03o", 0xFF & (int)*p);
 947         } else {
 948             int n = 0;
 949             if (*p == '\\' || *p == '(' || *p == ')')
 950                 c[n++] = '\\';
 951             c[n++] = *p;
 952             c[n] = '\0';
 953         }
 954         add(o, c);
 955     }
 956     add(o, ")");
 957 }
 958
 959 static void pdf_string(void (*add)(object *, char const *),
 960                        object *o, char const *str)
 961 {
 962     pdf_string_len(add, o, str, strlen(str));
 963 }