#include <assert.h>
#include "halibut.h"
#include "paper.h"
+#include "deflate.h"
#define TREE_BRANCH 2 /* max branching factor in page tree */
paragraph *pdf_config_filename(char *filename)
{
- paragraph *p;
- wchar_t *ufilename, *up;
- int len;
-
- p = mknew(paragraph);
- memset(p, 0, sizeof(*p));
- p->type = para_Config;
- p->next = NULL;
- p->fpos.filename = "<command line>";
- p->fpos.line = p->fpos.col = -1;
-
- ufilename = ufroma_dup(filename);
- len = ustrlen(ufilename) + 2 + lenof(L"pdf-filename");
- p->keyword = mknewa(wchar_t, len);
- up = p->keyword;
- ustrcpy(up, L"pdf-filename");
- up = uadv(up);
- ustrcpy(up, ufilename);
- up = uadv(up);
- *up = L'\0';
- assert(up - p->keyword < len);
- sfree(ufilename);
-
- return p;
+ return cmdline_cfg_simple("pdf-filename", filename, NULL);
}
typedef struct object_Tag object;
static object *new_object(objlist *list);
static void objtext(object *o, char const *text);
static void objstream(object *o, char const *text);
+static void pdf_string(void (*add)(object *, char const *),
+ object *, char const *);
+static void pdf_string_len(void (*add)(object *, char const *),
+ object *, char const *, int);
static void objref(object *o, object *dest);
+static char *pdf_outline_convert(wchar_t *s, int *len);
+
+static int is_std_font(char const *name);
static void make_pages_node(object *node, object *parent, page_data *first,
- page_data *last, object *resources);
+ page_data *last, object *resources,
+ object *mediabox);
+static int make_outline(object *parent, outline_element *start, int n,
+ int open);
+static int pdf_versionid(FILE *fp, word *words);
void pdf_backend(paragraph *sourceform, keywordlist *keywords,
indexdata *idx, void *vdoc) {
char *filename;
paragraph *p;
objlist olist;
- object *o, *cat, *outlines, *pages, *resources;
+ object *o, *info, *cat, *outlines, *pages, *resources, *mediabox;
int fileoff;
IGNORE(keywords);
filename = dupstr("output.pdf");
for (p = sourceform; p; p = p->next) {
- p->private_data = NULL;
- if (p->type == para_Config && p->parent) {
+ if (p->type == para_Config) {
if (!ustricmp(p->keyword, L"pdf-filename")) {
sfree(filename);
- filename = utoa_dup(uadv(p->keyword));
+ filename = dupstr(adv(p->origkeyword));
}
}
}
olist.head = olist.tail = NULL;
olist.number = 1;
+ {
+ char buf[256];
+
+ info = new_object(&olist);
+ objtext(info, "<<\n");
+ if (doc->n_outline_elements > 0) {
+ char *title;
+ int titlelen;
+
+ title =
+ pdf_outline_convert(doc->outline_elements->pdata->outline_title,
+ &titlelen);
+ objtext(info, "/Title ");
+ pdf_string_len(objtext, info, title, titlelen);
+ sfree(title);
+ objtext(info, "\n");
+ }
+ objtext(info, "/Producer ");
+ sprintf(buf, "Halibut, %s", version);
+ pdf_string(objtext, info, buf);
+ objtext(info, "\n>>\n");
+ }
+
cat = new_object(&olist);
- outlines = new_object(&olist);
+ if (doc->n_outline_elements > 0)
+ outlines = new_object(&olist);
+ else
+ outlines = NULL;
pages = new_object(&olist);
resources = new_object(&olist);
/*
- * We currently don't support outlines, so here's a null
- * outlines dictionary.
- */
- objtext(outlines, "<<\n/Type Outlines\n/Count 0\n>>\n");
-
- /*
* The catalogue just contains references to the outlines and
- * pages objects.
+ * pages objects, and the pagelabels dictionary.
*/
- objtext(cat, "<<\n/Type /Catalog\n/Outlines ");
- objref(cat, outlines);
+ objtext(cat, "<<\n/Type /Catalog");
+ if (outlines) {
+ objtext(cat, "\n/Outlines ");
+ objref(cat, outlines);
+ }
objtext(cat, "\n/Pages ");
objref(cat, pages);
+ /* Halibut just numbers pages 1, 2, 3, ... */
+ objtext(cat, "\n/PageLabels<</Nums[0<</S/D>>]>>");
+ if (outlines)
+ objtext(cat, "\n/PageMode /UseOutlines");
objtext(cat, "\n>>\n");
/*
* providing all the font objects and names to call them by.
*/
font_index = 0;
- objtext(resources, "<<\n/Font <<\n");
+ objtext(resources, "<<\n/ProcSet [/PDF/Text]\n/Font <<\n");
for (fe = doc->fonts->head; fe; fe = fe->next) {
char fname[40];
- int i;
+ int i, prev;
object *font;
sprintf(fname, "f%d", font_index++);
objtext(font, "<<\n/Type /Font\n/Subtype /Type1\n/Name /");
objtext(font, fe->name);
objtext(font, "\n/BaseFont /");
- objtext(font, fe->font->name);
+ objtext(font, fe->font->info->name);
objtext(font, "\n/Encoding <<\n/Type /Encoding\n/Differences [");
for (i = 0; i < 256; i++) {
char buf[20];
if (!fe->vector[i])
continue;
- sprintf(buf, "\n%d /", i);
- objtext(font, buf);
- objtext(font, fe->vector[i] ? fe->vector[i] : ".notdef");
+ if (i != prev + 1) {
+ sprintf(buf, "\n%d", i);
+ objtext(font, buf);
+ }
+ objtext(font, i % 8 ? "/" : "\n/");
+ objtext(font, fe->vector[i]);
+ prev = i;
}
objtext(font, "\n]\n>>\n");
- {
+#define FF_FIXEDPITCH 0x00000001
+#define FF_SERIF 0x00000002
+#define FF_SYMBOLIC 0x00000004
+#define FF_SCRIPT 0x00000008
+#define FF_NONSYMBOLIC 0x00000020
+#define FF_ITALIC 0x00000040
+#define FF_ALLCAP 0x00010000
+#define FF_SMALLCAP 0x00020000
+#define FF_FORCEBOLD 0x00040000
+
+ if (!is_std_font(fe->font->info->name)){
object *widths = new_object(&olist);
- objtext(font, "/FirstChar 0\n/LastChar 255\n/Widths ");
+ object *fontdesc = new_object(&olist);
+ int firstchar = -1, lastchar = -1;
+ char buf[80];
+ font_info const *fi = fe->font->info;
+ int flags;
+ for (i = 0; i < 256; i++)
+ if (fe->indices[i] >= 0) {
+ if (firstchar < 0) firstchar = i;
+ lastchar = i;
+ }
+ sprintf(buf, "/FirstChar %d\n/LastChar %d\n/Widths ",
+ firstchar, lastchar);
+ objtext(font, buf);
objref(font, widths);
objtext(font, "\n");
objtext(widths, "[\n");
- for (i = 0; i < 256; i++) {
- char buf[80];
+ for (i = firstchar; i <= lastchar; i++) {
double width;
if (fe->indices[i] < 0)
width = 0.0;
else
- width = fe->font->widths[fe->indices[i]];
- sprintf(buf, "%g\n", 1000.0 * width / 4096.0);
+ width = fi->widths[fe->indices[i]];
+ sprintf(buf, "%g\n", 1000.0 * width / FUNITS_PER_PT);
objtext(widths, buf);
}
objtext(widths, "]\n");
+ objtext(font, "/FontDescriptor ");
+ objref(font, fontdesc);
+ objtext(fontdesc, "<<\n/Type /FontDescriptor\n/Name /");
+ objtext(fontdesc, fi->name);
+ flags = 0;
+ if (fi->italicangle) flags |= FF_ITALIC;
+ flags |= FF_NONSYMBOLIC;
+ sprintf(buf, "\n/Flags %d\n", flags);
+ objtext(fontdesc, buf);
+ sprintf(buf, "/FontBBox [%g %g %g %g]\n", fi->fontbbox[0],
+ fi->fontbbox[1], fi->fontbbox[2], fi->fontbbox[3]);
+ objtext(fontdesc, buf);
+ sprintf(buf, "/ItalicAngle %g\n", fi->italicangle);
+ objtext(fontdesc, buf);
+ sprintf(buf, "/Ascent %g\n", fi->ascent);
+ objtext(fontdesc, buf);
+ sprintf(buf, "/Descent %g\n", fi->descent);
+ objtext(fontdesc, buf);
+ sprintf(buf, "/CapHeight %g\n", fi->capheight);
+ objtext(fontdesc, buf);
+ sprintf(buf, "/XHeight %g\n", fi->xheight);
+ objtext(fontdesc, buf);
+ sprintf(buf, "/StemH %g\n", fi->stemh);
+ objtext(fontdesc, buf);
+ sprintf(buf, "/StemV %g\n", fi->stemv);
+ objtext(fontdesc, buf);
+ if (fi->fp) {
+ object *fontfile = new_object(&olist);
+ char buf[513];
+ size_t len;
+ rewind(fi->fp);
+ do {
+ len = fread(buf, 1, sizeof(buf)-1, fi->fp);
+ buf[len] = 0;
+ objstream(fontfile, buf);
+ } while (len == sizeof(buf)-1);
+ objtext(fontdesc, "/FontFile ");
+ objref(fontdesc, fontfile);
+ }
+ objtext(fontdesc, "\n>>\n");
}
- objtext(font, ">>\n");
+ objtext(font, "\n>>\n");
}
objtext(resources, ">>\n>>\n");
+ {
+ char buf[255];
+ mediabox = new_object(&olist);
+ sprintf(buf, "[0 0 %g %g]\n",
+ doc->paper_width / FUNITS_PER_PT,
+ doc->paper_height / FUNITS_PER_PT);
+ objtext(mediabox, buf);
+ }
+
/*
* Define the page objects for each page, and get each one
* ready to have a `Parent' specification added to it.
/*
* Recursively build the page tree.
*/
- make_pages_node(pages, NULL, doc->pages, NULL, resources);
+ make_pages_node(pages, NULL, doc->pages, NULL, resources, mediabox);
/*
* Create and render the individual pages.
for (page = doc->pages; page; page = page->next) {
object *opage, *cstr;
rect *r;
- text_fragment *frag;
+ text_fragment *frag, *frag_end;
char buf[256];
+ int x, y, lx, ly;
opage = (object *)page->spare;
/*
* that it's inheritable and may be omitted if it's present
* in a Pages node. In our case it is: it's present in the
* topmost /Pages node because we carefully put it there.
- * So we don't need a /Resources entry here.
+ * So we don't need a /Resources entry here. The same applies
+ * to /MediaBox.
*/
- sprintf(buf, "/MediaBox [0 0 %g %g]\n",
- doc->paper_width / 4096.0, doc->paper_height / 4096.0);
- objtext(opage, buf);
/*
* Now we're ready to define a content stream containing
*/
for (r = page->first_rect; r; r = r->next) {
char buf[512];
- sprintf(buf, "%g %g %g %g re f\n", r->x / 4096.0,
- r->y / 4096.0, r->w / 4096.0, r->h / 4096.0);
+ sprintf(buf, "%g %g %g %g re f\n",
+ r->x / FUNITS_PER_PT, r->y / FUNITS_PER_PT,
+ r->w / FUNITS_PER_PT, r->h / FUNITS_PER_PT);
objstream(cstr, buf);
}
objstream(cstr, "BT\n");
- for (frag = page->first_text; frag; frag = frag->next) {
- char *c;
+ /*
+ * PDF tracks two separate current positions: the position
+ * given in the `line matrix' and the position given in the
+ * `text matrix'. We must therefore track both as well.
+ * They start off at -1 (unset).
+ */
+ lx = ly = -1;
+ x = y = -1;
+
+ frag = page->first_text;
+ while (frag) {
+ /*
+ * For compactness, I'm going to group text fragments
+ * into subsequences that use the same font+size. So
+ * first find the end of this subsequence.
+ */
+ for (frag_end = frag;
+ (frag_end &&
+ frag_end->fe == frag->fe &&
+ frag_end->fontsize == frag->fontsize);
+ frag_end = frag_end->next);
+
+ /*
+ * Now select the text fragment, and prepare to display
+ * the text.
+ */
objstream(cstr, "/");
objstream(cstr, frag->fe->name);
- sprintf(buf, " %d Tf 1 0 0 1 %g %g Tm (", frag->fontsize,
- frag->x/4096.0, frag->y/4096.0);
+ sprintf(buf, " %d Tf ", frag->fontsize);
objstream(cstr, buf);
- for (c = frag->text; *c; c++) {
- if (*c == '(' || *c == ')' || *c == '\\')
- objstream(cstr, "\\");
- buf[0] = *c;
- buf[1] = '\0';
+ while (frag && frag != frag_end) {
+ /*
+ * Place the text position for the first piece of
+ * text.
+ */
+ if (lx < 0) {
+ sprintf(buf, "1 0 0 1 %g %g Tm ",
+ frag->x/FUNITS_PER_PT, frag->y/FUNITS_PER_PT);
+ } else {
+ sprintf(buf, "%g %g Td ",
+ (frag->x - lx)/FUNITS_PER_PT,
+ (frag->y - ly)/FUNITS_PER_PT);
+ }
objstream(cstr, buf);
+ lx = x = frag->x;
+ ly = y = frag->y;
+
+ /*
+ * See if we're going to use Tj (show a single
+ * string) or TJ (show an array of strings with
+ * x-spacings between them). We determine this by
+ * seeing if there's more than one text fragment in
+ * sequence with the same y-coordinate.
+ */
+ if (frag->next && frag->next != frag_end &&
+ frag->next->y == y) {
+ /*
+ * The TJ strategy.
+ */
+ objstream(cstr, "[");
+ while (frag && frag != frag_end && frag->y == y) {
+ if (frag->x != x) {
+ sprintf(buf, "%g",
+ (x - frag->x) * 1000.0 /
+ (FUNITS_PER_PT * frag->fontsize));
+ objstream(cstr, buf);
+ }
+ pdf_string(objstream, cstr, frag->text);
+ x = frag->x + frag->width;
+ frag = frag->next;
+ }
+ objstream(cstr, "]TJ\n");
+ } else
+ {
+ /*
+ * The Tj strategy.
+ */
+ pdf_string(objstream, cstr, frag->text);
+ objstream(cstr, "Tj\n");
+ frag = frag->next;
+ }
}
-
- objstream(cstr, ") Tj\n");
}
objstream(cstr, "ET");
objtext(opage, "/Annots [\n");
for (xr = page->first_xref; xr; xr = xr->next) {
- object *annot;
char buf[256];
- annot = new_object(&olist);
- objref(opage, annot);
- objtext(opage, "\n");
-
- objtext(annot, "<<\n/Type /Annot\n/Subtype /Link\n/Rect [");
+ objtext(opage, "<</Subtype/Link\n/Rect[");
sprintf(buf, "%g %g %g %g",
- xr->lx / 4096.0, xr->by / 4096.0,
- xr->rx / 4096.0, xr->ty / 4096.0);
- objtext(annot, buf);
- objtext(annot, "]\n/Border [0 0 0]\n");
+ xr->lx / FUNITS_PER_PT, xr->by / FUNITS_PER_PT,
+ xr->rx / FUNITS_PER_PT, xr->ty / FUNITS_PER_PT);
+ objtext(opage, buf);
+ objtext(opage, "]/Border[0 0 0]\n");
if (xr->dest.type == PAGE) {
- objtext(annot, "/Dest [");
- objref(annot, (object *)xr->dest.page->spare);
- objtext(annot, " /XYZ null null null]\n");
+ objtext(opage, "/Dest[");
+ objref(opage, (object *)xr->dest.page->spare);
+ objtext(opage, "/XYZ null null null]");
} else {
- char *p;
-
- objtext(annot, "/A <<\n/Type /Action\n/S /URI\n/URI (");
- for (p = xr->dest.url; *p; p++) {
- char c[2];
- c[0] = *p;
- c[1] = '\0';
- if (*p == '(' || *p == ')' || *p == '\\')
- objtext(annot, "\\");
- objtext(annot, c);
- }
- objtext(annot, ")\n>>\n");
+ objtext(opage, "/A<</S/URI/URI");
+ pdf_string(objtext, opage, xr->dest.url);
+ objtext(opage, ">>");
}
- objtext(annot, ">>\n");
+ objtext(opage, ">>\n");
}
objtext(opage, "]\n");
}
/*
+ * Set up the outlines dictionary.
+ */
+ if (outlines) {
+ int topcount;
+ char buf[80];
+
+ objtext(outlines, "<<\n/Type /Outlines\n");
+ topcount = make_outline(outlines, doc->outline_elements,
+ doc->n_outline_elements, TRUE);
+ sprintf(buf, "/Count %d\n>>\n", topcount);
+ objtext(outlines, buf);
+ }
+
+ /*
* Assemble the final linear form of every object.
*/
for (o = olist.head; o; o = o->next) {
rdstringc rs = {0, 0, NULL};
char text[80];
+ deflate_compress_ctx *zcontext;
+ void *zbuf;
+ int zlen;
sprintf(text, "%d 0 obj\n", o->number);
rdaddsc(&rs, text);
if (!o->main.text && o->stream.text) {
- sprintf(text, "<<\n/Length %d\n>>\n", o->stream.pos);
+ zcontext = deflate_compress_new(DEFLATE_TYPE_ZLIB);
+ deflate_compress_data(zcontext, o->stream.text, o->stream.pos,
+ DEFLATE_END_OF_DATA, &zbuf, &zlen);
+ deflate_compress_free(zcontext);
+ sprintf(text, "<<\n/Filter/FlateDecode\n/Length %d\n>>\n", zlen);
rdaddsc(&o->main, text);
}
rdaddc(&rs, '\n');
if (o->stream.text) {
- /*
- * FIXME: If we ever start compressing stream data then
- * it will have zero bytes in it, so we'll have to be
- * more careful than this.
- */
rdaddsc(&rs, "stream\n");
- rdaddsc(&rs, o->stream.text);
+ rdaddsn(&rs, zbuf, zlen);
rdaddsc(&rs, "\nendstream\n");
sfree(o->stream.text);
+ sfree(zbuf);
}
rdaddsc(&rs, "endobj\n");
}
/*
- * Header
+ * Header. I'm going to put the version IDs in the header as
+ * well, simply in PDF comments. The PDF Reference also suggests
+ * that binary PDF files contain four top-bit-set characters in
+ * the second line.
*/
- fileoff = fprintf(fp, "%%PDF-1.3\n");
+ fileoff = fprintf(fp, "%%PDF-1.3\n%% L\xc3\xba\xc3\xb0""a\n");
+ for (p = sourceform; p; p = p->next)
+ if (p->type == para_VersionID)
+ fileoff += pdf_versionid(fp, p->words);
/*
* Body
/*
* Trailer
*/
- fprintf(fp, "trailer\n<<\n/Size %d\n/Root %d 0 R\n>>\n",
- olist.tail->number + 1, cat->number);
+ fprintf(fp, "trailer\n<<\n/Size %d\n/Root %d 0 R\n/Info %d 0 R\n>>\n",
+ olist.tail->number + 1, cat->number, info->number);
fprintf(fp, "startxref\n%d\n%%%%EOF\n", fileoff);
fclose(fp);
static object *new_object(objlist *list)
{
- object *obj = mknew(object);
+ object *obj = snew(object);
obj->list = list;
rdaddsc(&o->main, buf);
}
+static char const * const stdfonts[] = {
+ "Times-Roman", "Times-Bold", "Times-Italic", "Times-BoldItalic",
+ "Helvetica", "Helvetica-Bold", "Helvetica-Oblique","Helvetica-BoldOblique",
+ "Courier", "Courier-Bold", "Courier-Oblique", "Courier-BoldOblique",
+ "Symbol", "ZapfDingbats"
+};
+
+static int is_std_font(char const *name) {
+ unsigned i;
+ for (i = 0; i < lenof(stdfonts); i++)
+ if (strcmp(name, stdfonts[i]) == 0)
+ return TRUE;
+ return FALSE;
+}
+
static void make_pages_node(object *node, object *parent, page_data *first,
- page_data *last, object *resources)
+ page_data *last, object *resources,
+ object *mediabox)
{
int count;
page_data *page;
objtext((object *)thisfirst->spare, "\n");
} else {
object *newnode = new_object(node->list);
- make_pages_node(newnode, node, thisfirst, thislast, NULL);
+ make_pages_node(newnode, node, thisfirst, thislast,
+ NULL, NULL);
objref(node, newnode);
}
objtext(node, "\n");
objref(node, resources);
objtext(node, "\n");
}
+ if (mediabox) {
+ objtext(node, "/MediaBox ");
+ objref(node, mediabox);
+ objtext(node, "\n");
+ }
objtext(node, ">>\n");
}
+
+/*
+ * In text on the page, PDF uses the PostScript font model, which
+ * means that glyphs are identified by PS strings and hence font
+ * encoding can be managed independently of the supplied encoding
+ * of the font. However, in the document outline, the PDF spec
+ * encodes in either PDFDocEncoding (a custom superset of
+ * ISO-8859-1) or UTF-16BE.
+ */
+static char *pdf_outline_convert(wchar_t *s, int *len) {
+ char *ret;
+
+ ret = utoa_careful_dup(s, CS_PDF);
+
+ /*
+ * Very silly special case: if the returned string begins with
+ * FE FF, then the PDF reader will mistake it for a UTF-16BE
+ * string. So in this case we give up on PDFDocEncoding and
+ * encode it in UTF-16 straight away.
+ */
+ if (ret && ret[0] == '\xFE' && ret[1] == '\xFF') {
+ sfree(ret);
+ ret = NULL;
+ }
+
+ if (!ret) {
+ ret = utoa_dup_len(s, CS_UTF16BE, len);
+ } else {
+ *len = strlen(ret);
+ }
+
+ return ret;
+}
+
+static int make_outline(object *parent, outline_element *items, int n,
+ int open)
+{
+ int level, totalcount = 0;
+ outline_element *itemp;
+ object *curr, *prev = NULL, *first = NULL, *last = NULL;
+
+ assert(n > 0);
+
+ level = items->level;
+
+ while (n > 0) {
+ char *title;
+ int titlelen;
+
+ /*
+ * Here we expect to be sitting on an item at the given
+ * level. So we start by constructing an outline entry for
+ * that item.
+ */
+ assert(items->level == level);
+
+ title = pdf_outline_convert(items->pdata->outline_title, &titlelen);
+
+ totalcount++;
+ curr = new_object(parent->list);
+ if (!first) first = curr;
+ last = curr;
+ objtext(curr, "<<\n/Title ");
+ pdf_string_len(objtext, curr, title, titlelen);
+ sfree(title);
+ objtext(curr, "\n/Parent ");
+ objref(curr, parent);
+ objtext(curr, "\n/Dest [");
+ objref(curr, (object *)items->pdata->first->page->spare);
+ objtext(curr, " /XYZ null null null]\n");
+ if (prev) {
+ objtext(curr, "/Prev ");
+ objref(curr, prev);
+ objtext(curr, "\n");
+
+ objtext(prev, "/Next ");
+ objref(prev, curr);
+ objtext(prev, "\n>>\n");
+ }
+ prev = curr;
+
+ items++, n--;
+ for (itemp = items; itemp < items+n && itemp->level > level;
+ itemp++);
+
+ if (itemp > items) {
+ char buf[80];
+ int count = make_outline(curr, items, itemp - items, FALSE);
+ if (!open)
+ count = -count;
+ else
+ totalcount += count;
+ sprintf(buf, "/Count %d\n", count);
+ objtext(curr, buf);
+ }
+
+ n -= itemp - items;
+ items = itemp;
+ }
+ objtext(prev, ">>\n");
+
+ assert(first && last);
+ objtext(parent, "/First ");
+ objref(parent, first);
+ objtext(parent, "\n/Last ");
+ objref(parent, last);
+ objtext(parent, "\n");
+
+ return totalcount;
+}
+
+static int pdf_versionid(FILE *fp, word *words)
+{
+ int ret;
+
+ ret = fprintf(fp, "%% ");
+
+ for (; words; words = words->next) {
+ char *text;
+ int type;
+
+ switch (words->type) {
+ case word_HyperLink:
+ case word_HyperEnd:
+ case word_UpperXref:
+ case word_LowerXref:
+ case word_XrefEnd:
+ case word_IndexRef:
+ continue;
+ }
+
+ type = removeattr(words->type);
+
+ switch (type) {
+ case word_Normal:
+ text = utoa_dup(words->text, CS_ASCII);
+ break;
+ case word_WhiteSpace:
+ text = dupstr(" ");
+ break;
+ case word_Quote:
+ text = dupstr("'");
+ break;
+ }
+
+ fputs(text, fp);
+ ret += strlen(text);
+ sfree(text);
+ }
+
+ ret += fprintf(fp, "\n");
+
+ return ret;
+}
+
+static void pdf_string_len(void (*add)(object *, char const *),
+ object *o, char const *str, int len)
+{
+ char const *p;
+
+ add(o, "(");
+ for (p = str; len > 0; p++, len--) {
+ char c[10];
+ if (*p < ' ' || *p > '~') {
+ sprintf(c, "\\%03o", 0xFF & (int)*p);
+ } else {
+ int n = 0;
+ if (*p == '\\' || *p == '(' || *p == ')')
+ c[n++] = '\\';
+ c[n++] = *p;
+ c[n] = '\0';
+ }
+ add(o, c);
+ }
+ add(o, ")");
+}
+
+static void pdf_string(void (*add)(object *, char const *),
+ object *o, char const *str)
+{
+ pdf_string_len(add, o, str, strlen(str));
+}