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");
 213         } else {
 214             objtext(font, "/Subtype /Type1\n");
 215             objtext(font, "\n/Encoding <<\n/Type /Encoding\n/Differences [");
 216
 217             for (i = 0; i < 256; i++) {
 218                 char buf[20];
 219                 if (fe->vector[i] == NOGLYPH)
 220                     continue;
 221                 if (i != prev + 1) {
 222                     sprintf(buf, "\n%d", i);
 223                     objtext(font, buf);
 224                 }
 225                 objtext(font, i % 8 ? "/" : "\n/");
 226                 objtext(font, glyph_extern(fe->vector[i]));
 227                 prev = i;
 228             }
 229
 230             objtext(font, "\n]\n>>\n");
 231             if (!is_std_font(fe->font->info->name)){
 232                 object *widths = new_object(&olist);
 233                 int firstchar = -1, lastchar = -1;
 234                 for (i = 0; i < 256; i++)
 235                     if (fe->vector[i] != NOGLYPH) {
 236                         if (firstchar < 0) firstchar = i;
 237                         lastchar = i;
 238                     }
 239                 sprintf(buf, "/FirstChar %d\n/LastChar %d\n/Widths ",
 240                         firstchar, lastchar);
 241                 objtext(font, buf);
 242                 objref(font, widths);
 243                 objtext(font, "\n");
 244                 objtext(widths, "[\n");
 245                 for (i = firstchar; i <= lastchar; i++) {
 246                     double width;
 247                     if (fe->vector[i] == NOGLYPH)
 248                         width = 0.0;
 249                     else
 250                         width = find_width(fe->font, fe->vector[i]);
 251                     sprintf(buf, "%g\n", 1000.0 * width / FUNITS_PER_PT);
 252                     objtext(widths, buf);
 253                 }
 254                 objtext(widths, "]\n");
 255                 objtext(font, "/FontDescriptor ");
 256                 objref(font, fontdesc);
 257             }
 258
 259         }
 260
 261         if (!is_std_font(fe->font->info->name)) {
 262             if (fi->fontfile && fi->filetype == TYPE1) {
 263                 object *fontfile = new_object(&olist);
 264                 size_t len;
 265                 char *ffbuf;
 266
 267                 pf_part1((font_info *)fi, &ffbuf, &len);
 268                 objstream_len(fontfile, ffbuf, len);
 269                 sfree(ffbuf);
 270                 sprintf(buf, "<<\n/Length1 %lu\n", (unsigned long)len);
 271                 objtext(fontfile, buf);
 272                 pf_part2((font_info *)fi, &ffbuf, &len);
 273                 objstream_len(fontfile, ffbuf, len);
 274                 sfree(ffbuf);
 275                 sprintf(buf, "/Length2 %lu\n", (unsigned long)len);
 276                 objtext(fontfile, buf);
 277                 objtext(fontfile, "/Length3 0\n");
 278                 objtext(fontdesc, "/FontFile ");
 279                 objref(fontdesc, fontfile);
 280             } else if (fi->fontfile && fi->filetype == TRUETYPE) {
 281                 object *fontfile = new_object(&olist);
 282                 size_t len;
 283                 char *ffbuf;
 284
 285                 sfnt_data((font_info *)fi, &ffbuf, &len);
 286                 objstream_len(fontfile, ffbuf, len);
 287                 sprintf(buf, "<<\n/Length1 %lu\n", (unsigned long)len);
 288                 objtext(fontfile, buf);
 289                 objtext(fontdesc, "/FontFile2 ");
 290                 objref(fontdesc, fontfile);
 291             }
 292             objtext(fontdesc, "\n>>\n");
 293         }
 294
 295         objtext(font, "\n>>\n");
 296     }
 297     objtext(resources, ">>\n>>\n");
 298
 299     {
 300         char buf[255];
 301         mediabox = new_object(&olist);
 302         sprintf(buf, "[0 0 %g %g]\n",
 303                 doc->paper_width / FUNITS_PER_PT,
 304                 doc->paper_height / FUNITS_PER_PT);
 305         objtext(mediabox, buf);
 306     }
 307
 308     /*
 309      * Define the page objects for each page, and get each one
 310      * ready to have a `Parent' specification added to it.
 311      */
 312     for (page = doc->pages; page; page = page->next) {
 313         object *opage;
 314
 315         opage = new_object(&olist);
 316         page->spare = opage;
 317         objtext(opage, "<<\n/Type /Page\n");
 318     }
 319
 320     /*
 321      * Recursively build the page tree.
 322      */
 323     make_pages_node(pages, NULL, doc->pages, NULL, resources, mediabox);
 324
 325     /*
 326      * Create and render the individual pages.
 327      */
 328     pageno = 0;
 329     for (page = doc->pages; page; page = page->next) {
 330         object *opage, *cstr;
 331         rect *r;
 332         text_fragment *frag, *frag_end;
 333         char buf[256];
 334         int x, y, lx, ly;
 335
 336         opage = (object *)page->spare;
 337         /*
 338          * At this point the page dictionary is already
 339          * half-written, with /Type and /Parent already present. We
 340          * continue from there.
 341          */
 342
 343         /*
 344          * The PDF spec says /Resources is required, but also says
 345          * that it's inheritable and may be omitted if it's present
 346          * in a Pages node. In our case it is: it's present in the
 347          * topmost /Pages node because we carefully put it there.
 348          * So we don't need a /Resources entry here.  The same applies
 349          * to /MediaBox.
 350          */
 351
 352         /*
 353          * Now we're ready to define a content stream containing
 354          * the actual text on the page.
 355          */
 356         cstr = new_object(&olist);
 357         objtext(opage, "/Contents ");
 358         objref(opage, cstr);
 359         objtext(opage, "\n");
 360
 361         /*
 362          * Render any rectangles on the page.
 363          */
 364         for (r = page->first_rect; r; r = r->next) {
 365             char buf[512];
 366             sprintf(buf, "%g %g %g %g re f\n",
 367                     r->x / FUNITS_PER_PT, r->y / FUNITS_PER_PT,
 368                     r->w / FUNITS_PER_PT, r->h / FUNITS_PER_PT);
 369             objstream(cstr, buf);
 370         }
 371
 372         objstream(cstr, "BT\n");
 373
 374         /*
 375          * PDF tracks two separate current positions: the position
 376          * given in the `line matrix' and the position given in the
 377          * `text matrix'. We must therefore track both as well.
 378          * They start off at -1 (unset).
 379          */
 380         lx = ly = -1;
 381         x = y = -1;
 382
 383         frag = page->first_text;
 384         while (frag) {
 385             /*
 386              * For compactness, I'm going to group text fragments
 387              * into subsequences that use the same font+size. So
 388              * first find the end of this subsequence.
 389              */
 390             for (frag_end = frag;
 391                  (frag_end &&
 392                   frag_end->fe == frag->fe &&
 393                   frag_end->fontsize == frag->fontsize);
 394                  frag_end = frag_end->next);
 395
 396             /*
 397              * Now select the text fragment, and prepare to display
 398              * the text.
 399              */
 400             objstream(cstr, "/");
 401             objstream(cstr, frag->fe->name);
 402             sprintf(buf, " %d Tf ", frag->fontsize);
 403             objstream(cstr, buf);
 404
 405             while (frag && frag != frag_end) {
 406                 /*
 407                  * Place the text position for the first piece of
 408                  * text.
 409                  */
 410                 if (lx < 0) {
 411                     sprintf(buf, "1 0 0 1 %g %g Tm ",
 412                             frag->x/FUNITS_PER_PT, frag->y/FUNITS_PER_PT);
 413                 } else {
 414                     sprintf(buf, "%g %g Td ",
 415                             (frag->x - lx)/FUNITS_PER_PT,
 416                             (frag->y - ly)/FUNITS_PER_PT);
 417                 }
 418                 objstream(cstr, buf);
 419                 lx = x = frag->x;
 420                 ly = y = frag->y;
 421
 422                 /*
 423                  * See if we're going to use Tj (show a single
 424                  * string) or TJ (show an array of strings with
 425                  * x-spacings between them). We determine this by
 426                  * seeing if there's more than one text fragment in
 427                  * sequence with the same y-coordinate.
 428                  */
 429                 if (frag->next && frag->next != frag_end &&
 430                     frag->next->y == y) {
 431                     /*
 432                      * The TJ strategy.
 433                      */
 434                     objstream(cstr, "[");
 435                     while (frag && frag != frag_end && frag->y == y) {
 436                         if (frag->x != x) {
 437                             sprintf(buf, "%g",
 438                                     (x - frag->x) * 1000.0 /
 439                                     (FUNITS_PER_PT * frag->fontsize));
 440                             objstream(cstr, buf);
 441                         }
 442                         pdf_string(objstream, cstr, frag->text);
 443                         x = frag->x + frag->width;
 444                         frag = frag->next;
 445                     }
 446                     objstream(cstr, "]TJ\n");
 447                 } else
 448                 {
 449                     /*
 450                      * The Tj strategy.
 451                      */
 452                     pdf_string(objstream, cstr, frag->text);
 453                     objstream(cstr, "Tj\n");
 454                     frag = frag->next;
 455                 }
 456             }
 457         }
 458         objstream(cstr, "ET");
 459
 460         /*
 461          * Also, we want an annotation dictionary containing the
 462          * cross-references from this page.
 463          */
 464         if (page->first_xref) {
 465             xref *xr;
 466             objtext(opage, "/Annots [\n");
 467
 468             for (xr = page->first_xref; xr; xr = xr->next) {
 469                 char buf[256];
 470
 471                 objtext(opage, "<</Subtype/Link\n/Rect[");
 472                 sprintf(buf, "%g %g %g %g",
 473                         xr->lx / FUNITS_PER_PT, xr->by / FUNITS_PER_PT,
 474                         xr->rx / FUNITS_PER_PT, xr->ty / FUNITS_PER_PT);
 475                 objtext(opage, buf);
 476                 objtext(opage, "]/Border[0 0 0]\n");
 477
 478                 if (xr->dest.type == PAGE) {
 479                     objtext(opage, "/Dest");
 480                     objdest(opage, xr->dest.page);
 481                 } else {
 482                     objtext(opage, "/A<</S/URI/URI");
 483                     pdf_string(objtext, opage, xr->dest.url);
 484                     objtext(opage, ">>");
 485                 }
 486
 487                 objtext(opage, ">>\n");
 488             }
 489
 490             objtext(opage, "]\n");
 491         }
 492
 493         objtext(opage, ">>\n");
 494     }
 495
 496     /*
 497      * Set up the outlines dictionary.
 498      */
 499     if (outlines) {
 500         int topcount;
 501         char buf[80];
 502
 503         objtext(outlines, "<<\n/Type /Outlines\n");
 504         topcount = make_outline(outlines, doc->outline_elements,
 505                                 doc->n_outline_elements, TRUE);
 506         sprintf(buf, "/Count %d\n>>\n", topcount);
 507         objtext(outlines, buf);
 508     }
 509
 510     /*
 511      * Assemble the final linear form of every object.
 512      */
 513     for (o = olist.head; o; o = o->next) {
 514         rdstringc rs = {0, 0, NULL};
 515         char text[80];
 516         deflate_compress_ctx *zcontext;
 517         void *zbuf;
 518         int zlen;
 519
 520         sprintf(text, "%d 0 obj\n", o->number);
 521         rdaddsc(&rs, text);
 522
 523         if (o->stream.text) {
 524             if (!o->main.text)
 525                 rdaddsc(&o->main, "<<\n");
 526 #ifdef PDF_NOCOMPRESS
 527             zlen = o->stream.pos;
 528             zbuf = snewn(zlen, char);
 529             memcpy(zbuf, o->stream.text, zlen);
 530             sprintf(text, "/Length %d\n>>\n", zlen);
 531 #else
 532             zcontext = deflate_compress_new(DEFLATE_TYPE_ZLIB);
 533             deflate_compress_data(zcontext, o->stream.text, o->stream.pos,
 534                                   DEFLATE_END_OF_DATA, &zbuf, &zlen);
 535             deflate_compress_free(zcontext);
 536             sprintf(text, "/Filter/FlateDecode\n/Length %d\n>>\n", zlen);
 537 #endif
 538             rdaddsc(&o->main, text);
 539         }
 540
 541         assert(o->main.text);
 542         rdaddsc(&rs, o->main.text);
 543         sfree(o->main.text);
 544
 545         if (rs.text[rs.pos-1] != '\n')
 546             rdaddc(&rs, '\n');
 547
 548         if (o->stream.text) {
 549             rdaddsc(&rs, "stream\n");
 550             rdaddsn(&rs, zbuf, zlen);
 551             rdaddsc(&rs, "\nendstream\n");
 552             sfree(o->stream.text);
 553             sfree(zbuf);
 554         }
 555
 556         rdaddsc(&rs, "endobj\n");
 557
 558         o->final = rs.text;
 559         o->size = rs.pos;
 560     }
 561
 562     /*
 563      * Write out the PDF file.
 564      */
 565
 566     fp = fopen(filename, "wb");
 567     if (!fp) {
 568         error(err_cantopenw, filename);
 569         return;
 570     }
 571
 572     /*
 573      * Header. I'm going to put the version IDs in the header as
 574      * well, simply in PDF comments.  The PDF Reference also suggests
 575      * that binary PDF files contain four top-bit-set characters in
 576      * the second line.
 577      */
 578     fileoff = fprintf(fp, "%%PDF-1.3\n%% L\xc3\xba\xc3\xb0""a\n");
 579     for (p = sourceform; p; p = p->next)
 580         if (p->type == para_VersionID)
 581             fileoff += pdf_versionid(fp, p->words);
 582
 583     /*
 584      * Body
 585      */
 586     for (o = olist.head; o; o = o->next) {
 587         o->fileoff = fileoff;
 588         fwrite(o->final, 1, o->size, fp);
 589         fileoff += o->size;
 590     }
 591
 592     /*
 593      * Cross-reference table
 594      */
 595     fprintf(fp, "xref\n");
 596     assert(olist.head->number == 1);
 597     fprintf(fp, "0 %d\n", olist.tail->number + 1);
 598     fprintf(fp, "0000000000 65535 f \n");
 599     for (o = olist.head; o; o = o->next) {
 600         char entry[40];
 601         sprintf(entry, "%010d 00000 n \n", o->fileoff);
 602         assert(strlen(entry) == 20);
 603         fputs(entry, fp);
 604     }
 605
 606     /*
 607      * Trailer
 608      */
 609     fprintf(fp, "trailer\n<<\n/Size %d\n/Root %d 0 R\n/Info %d 0 R\n>>\n",
 610             olist.tail->number + 1, cat->number, info->number);
 611     fprintf(fp, "startxref\n%d\n%%%%EOF\n", fileoff);
 612
 613     fclose(fp);
 614
 615     sfree(filename);
 616 }
 617
 618 object *new_object(objlist *list)
 619 {
 620     object *obj = snew(object);
 621
 622     obj->list = list;
 623
 624     obj->main.text = NULL;
 625     obj->main.pos = obj->main.size = 0;
 626     obj->stream.text = NULL;
 627     obj->stream.pos = obj->stream.size = 0;
 628
 629     obj->number = list->number++;
 630
 631     obj->next = NULL;
 632     if (list->tail)
 633         list->tail->next = obj;
 634     else
 635         list->head = obj;
 636     list->tail = obj;
 637
 638     obj->size = 0;
 639     obj->final = NULL;
 640
 641     return obj;
 642 }
 643
 644 void objtext(object *o, char const *text)
 645 {
 646     rdaddsc(&o->main, text);
 647 }
 648
 649 void objstream_len(object *o, char const *text, size_t len)
 650 {
 651     rdaddsn(&o->stream, text, len);
 652 }
 653
 654 void objstream(object *o, char const *text)
 655 {
 656     rdaddsc(&o->stream, text);
 657 }
 658
 659 static void objref(object *o, object *dest)
 660 {
 661     char buf[40];
 662     sprintf(buf, "%d 0 R", dest->number);
 663     rdaddsc(&o->main, buf);
 664 }
 665
 666 static void objdest(object *o, page_data *p) {
 667     objtext(o, "[");
 668     objref(o, (object *)p->spare);
 669     objtext(o, "/XYZ null null null]");
 670 }
 671
 672 static char const * const stdfonts[] = {
 673     "Times-Roman", "Times-Bold", "Times-Italic", "Times-BoldItalic",
 674     "Helvetica", "Helvetica-Bold", "Helvetica-Oblique","Helvetica-BoldOblique",
 675     "Courier", "Courier-Bold", "Courier-Oblique", "Courier-BoldOblique",
 676     "Symbol", "ZapfDingbats"
 677 };
 678
 679 static int is_std_font(char const *name) {
 680     unsigned i;
 681     for (i = 0; i < lenof(stdfonts); i++)
 682         if (strcmp(name, stdfonts[i]) == 0)
 683             return TRUE;
 684     return FALSE;
 685 }
 686
 687 static void make_pages_node(object *node, object *parent, page_data *first,
 688                             page_data *last, object *resources,
 689                             object *mediabox)
 690 {
 691     int count;
 692     page_data *page;
 693     char buf[80];
 694
 695     objtext(node, "<<\n/Type /Pages\n");
 696     if (parent) {
 697         objtext(node, "/Parent ");
 698         objref(node, parent);
 699         objtext(node, "\n");
 700     }
 701
 702     /*
 703      * Count the pages in this stretch, to see if there are few
 704      * enough to reference directly.
 705      */
 706     count = 0;
 707     for (page = first; page; page = page->next) {
 708         count++;
 709         if (page == last)
 710             break;
 711     }
 712
 713     sprintf(buf, "/Count %d\n/Kids [\n", count);
 714     objtext(node, buf);
 715
 716     if (count > TREE_BRANCH) {
 717         int i;
 718         page_data *thisfirst, *thislast;
 719
 720         page = first;
 721
 722         for (i = 0; i < TREE_BRANCH; i++) {
 723             int number = (i+1) * count / TREE_BRANCH - i * count / TREE_BRANCH;
 724             thisfirst = page;
 725             while (number--) {
 726                 thislast = page;
 727                 page = page->next;
 728             }
 729
 730             if (thisfirst == thislast) {
 731                 objref(node, (object *)thisfirst->spare);
 732                 objtext((object *)thisfirst->spare, "/Parent ");
 733                 objref((object *)thisfirst->spare, node);
 734                 objtext((object *)thisfirst->spare, "\n");
 735             } else {
 736                 object *newnode = new_object(node->list);
 737                 make_pages_node(newnode, node, thisfirst, thislast,
 738                                 NULL, NULL);
 739                 objref(node, newnode);
 740             }
 741             objtext(node, "\n");
 742         }
 743
 744         assert(thislast == last || page == NULL);
 745
 746     } else {
 747         for (page = first; page; page = page->next) {
 748             objref(node, (object *)page->spare);
 749             objtext(node, "\n");
 750             objtext((object *)page->spare, "/Parent ");
 751             objref((object *)page->spare, node);
 752             objtext((object *)page->spare, "\n");
 753             if (page == last)
 754                 break;
 755         }
 756     }
 757
 758     objtext(node, "]\n");
 759
 760     if (resources) {
 761         objtext(node, "/Resources ");
 762         objref(node, resources);
 763         objtext(node, "\n");
 764     }
 765     if (mediabox) {
 766         objtext(node, "/MediaBox ");
 767         objref(node, mediabox);
 768         objtext(node, "\n");
 769     }
 770
 771     objtext(node, ">>\n");
 772 }
 773
 774 /*
 775  * In text on the page, PDF uses the PostScript font model, which
 776  * means that glyphs are identified by PS strings and hence font
 777  * encoding can be managed independently of the supplied encoding
 778  * of the font. However, in the document outline, the PDF spec
 779  * encodes in either PDFDocEncoding (a custom superset of
 780  * ISO-8859-1) or UTF-16BE.
 781  */
 782 char *pdf_outline_convert(wchar_t *s, int *len) {
 783     char *ret;
 784
 785     ret = utoa_careful_dup(s, CS_PDF);
 786
 787     /*
 788      * Very silly special case: if the returned string begins with
 789      * FE FF, then the PDF reader will mistake it for a UTF-16BE
 790      * string. So in this case we give up on PDFDocEncoding and
 791      * encode it in UTF-16 straight away.
 792      */
 793     if (ret && ret[0] == '\xFE' && ret[1] == '\xFF') {
 794         sfree(ret);
 795         ret = NULL;
 796     }
 797
 798     if (!ret) {
 799         ret = utoa_dup_len(s, CS_UTF16BE, len);
 800     } else {
 801         *len = strlen(ret);
 802     }
 803
 804     return ret;
 805 }
 806
 807 static int make_outline(object *parent, outline_element *items, int n,
 808                         int open)
 809 {
 810     int level, totalcount = 0;
 811     outline_element *itemp;
 812     object *curr, *prev = NULL, *first = NULL, *last = NULL;
 813
 814     assert(n > 0);
 815
 816     level = items->level;
 817
 818     while (n > 0) {
 819         char *title;
 820         int titlelen;
 821
 822         /*
 823          * Here we expect to be sitting on an item at the given
 824          * level. So we start by constructing an outline entry for
 825          * that item.
 826          */
 827         assert(items->level == level);
 828
 829         title = pdf_outline_convert(items->pdata->outline_title, &titlelen);
 830
 831         totalcount++;
 832         curr = new_object(parent->list);
 833         if (!first) first = curr;
 834         last = curr;
 835         objtext(curr, "<<\n/Title ");
 836         pdf_string_len(objtext, curr, title, titlelen);
 837         sfree(title);
 838         objtext(curr, "\n/Parent ");
 839         objref(curr, parent);
 840         objtext(curr, "\n/Dest");
 841         objdest(curr, items->pdata->first->page);
 842         objtext(curr, "\n");
 843         if (prev) {
 844             objtext(curr, "/Prev ");
 845             objref(curr, prev);
 846             objtext(curr, "\n");
 847
 848             objtext(prev, "/Next ");
 849             objref(prev, curr);
 850             objtext(prev, "\n>>\n");
 851         }
 852         prev = curr;
 853
 854         items++, n--;
 855         for (itemp = items; itemp < items+n && itemp->level > level;
 856              itemp++);
 857
 858         if (itemp > items) {
 859             char buf[80];
 860             int count = make_outline(curr, items, itemp - items, FALSE);
 861             if (!open)
 862                 count = -count;
 863             else
 864                 totalcount += count;
 865             sprintf(buf, "/Count %d\n", count);
 866             objtext(curr, buf);
 867         }
 868
 869         n -= itemp - items;
 870         items = itemp;
 871     }
 872     objtext(prev, ">>\n");
 873
 874     assert(first && last);
 875     objtext(parent, "/First ");
 876     objref(parent, first);
 877     objtext(parent, "\n/Last ");
 878     objref(parent, last);
 879     objtext(parent, "\n");
 880
 881     return totalcount;
 882 }
 883
 884 static int pdf_versionid(FILE *fp, word *words)
 885 {
 886     int ret;
 887
 888     ret = fprintf(fp, "%% ");
 889
 890     for (; words; words = words->next) {
 891         char *text;
 892         int type;
 893
 894         switch (words->type) {
 895           case word_HyperLink:
 896           case word_HyperEnd:
 897           case word_UpperXref:
 898           case word_LowerXref:
 899           case word_XrefEnd:
 900           case word_IndexRef:
 901             continue;
 902         }
 903
 904         type = removeattr(words->type);
 905
 906         switch (type) {
 907           case word_Normal:
 908             text = utoa_dup(words->text, CS_ASCII);
 909             break;
 910           case word_WhiteSpace:
 911             text = dupstr(" ");
 912             break;
 913           case word_Quote:
 914             text = dupstr("'");
 915             break;
 916         }
 917
 918         fputs(text, fp);
 919         ret += strlen(text);
 920         sfree(text);
 921     }
 922
 923     ret += fprintf(fp, "\n");
 924
 925     return ret;
 926 }
 927
 928 static void pdf_string_len(void (*add)(object *, char const *),
 929                            object *o, char const *str, int len)
 930 {
 931     char const *p;
 932
 933     add(o, "(");
 934     for (p = str; len > 0; p++, len--) {
 935         char c[10];
 936         if (*p < ' ' || *p > '~') {
 937             sprintf(c, "\\%03o", 0xFF & (int)*p);
 938         } else {
 939             int n = 0;
 940             if (*p == '\\' || *p == '(' || *p == ')')
 941                 c[n++] = '\\';
 942             c[n++] = *p;
 943             c[n] = '\0';
 944         }
 945         add(o, c);
 946     }
 947     add(o, ")");
 948 }
 949
 950 static void pdf_string(void (*add)(object *, char const *),
 951                        object *o, char const *str)
 952 {
 953     pdf_string_len(add, o, str, strlen(str));
 954 }