Rework handling of PDF names for speed and memory.

Currently, every PDF name is allocated in a pdf_obj structure, and
comparisons are done using strcmp. Given that we can predict most
of the PDF names we'll use in a given file, this seems wasteful.

The pdf_obj type is opaque outside the pdf-object.c file, so we can
abuse it slightly without anyone outside knowing.

We collect a sorted list of names used in PDF (resources/pdf/names.txt),
and we add a utility (namedump) that preprocesses this into 2 header
files.

The first (include/mupdf/pdf/pdf-names-table.h, included as part of
include/mupdf/pdf/object.h), defines a set of "PDF_NAME_xxxx"
entries. These are pdf_obj *'s that callers can use to mean "A PDF
object that means literal name 'xxxx'"

The second (source/pdf/pdf-name-impl.h) is a C array of names.

We therefore update the code so that rather than passing "xxxx" to
functions (such as pdf_dict_gets(...)) we now pass PDF_NAME_xxxx (to
pdf_dict_get(...)). This is a fairly natural (if widespread) change.

The pdf_dict_getp (and sibling) functions that take a path (e.g.
"foo/bar/baz") are therefore supplemented with equivalents that
take a list (pdf_dict_getl(... , PDF_NAME_foo, PDF_NAME_bar,
PDF_NAME_baz, NULL)).

The actual implementation of this relies on the fact that small
pointer values are never valid values. For a given pdf_obj *p,
if NULL < (intptr_t)p < PDF_NAME__LIMIT then p is a literal
entry in the name table.

This enables us to do fast pointer compares and to skip expensive
strcmps.

Also, bring "null", "true" and "false" into the same style as PDF names.

Rather than using full pdf_obj structures for null/true/false, use
special pointer values just above the PDF_NAME_ table. This saves
memory and makes comparisons easier.

1 files changed, 35 insertions, 35 deletions

diff --git a/source/pdf/pdf-annot-edit.c b/source/pdf/pdf-annot-edit.c
index 565e3171..aef14e6f 100644
--- a/source/pdf/pdf-annot-edit.c
+++ b/source/pdf/pdf-annot-edit.c
@@ -45,8 +45,8 @@ pdf_update_annot(fz_context *ctx, pdf_document *doc, pdf_annot *annot)
 
 	obj = annot->obj;
 
-	ap = pdf_dict_gets(ctx, obj, "AP");
-	as = pdf_dict_gets(ctx, obj, "AS");
+	ap = pdf_dict_get(ctx, obj, PDF_NAME_AP);
+	as = pdf_dict_get(ctx, obj, PDF_NAME_AS);
 
 	if (pdf_is_dict(ctx, ap))
 	{
@@ -58,11 +58,11 @@ pdf_update_annot(fz_context *ctx, pdf_document *doc, pdf_annot *annot)
 			&& hp->gen == pdf_to_gen(ctx, obj)
 			&& (hp->state & HOTSPOT_POINTER_DOWN))
 		{
-			n = pdf_dict_gets(ctx, ap, "D"); /* down state */
+			n = pdf_dict_get(ctx, ap, PDF_NAME_D); /* down state */
 		}
 
 		if (n == NULL)
-			n = pdf_dict_gets(ctx, ap, "N"); /* normal state */
+			n = pdf_dict_get(ctx, ap, PDF_NAME_N); /* normal state */
 
 		/* lookup current state in sub-dictionary */
 		if (!pdf_is_stream(ctx, doc, pdf_to_num(ctx, n), pdf_to_gen(ctx, n)))
@@ -102,20 +102,20 @@ pdf_create_annot(fz_context *ctx, pdf_document *doc, pdf_page *page, fz_annot_ty
 		int ind_obj_num;
 		fz_rect rect = {0.0, 0.0, 0.0, 0.0};
 		const char *type_str = annot_type_str(type);
-		pdf_obj *annot_arr = pdf_dict_gets(ctx, page->me, "Annots");
+		pdf_obj *annot_arr = pdf_dict_get(ctx, page->me, PDF_NAME_Annots);
 		if (annot_arr == NULL)
 		{
 			annot_arr = pdf_new_array(ctx, doc, 0);
-			pdf_dict_puts_drop(ctx, page->me, "Annots", annot_arr);
+			pdf_dict_put_drop(ctx, page->me, PDF_NAME_Annots, annot_arr);
 		}
 
-		pdf_dict_puts_drop(ctx, annot_obj, "Type", pdf_new_name(ctx, doc, "Annot"));
+		pdf_dict_put_drop(ctx, annot_obj, PDF_NAME_Type, PDF_NAME_Annot);
 
-		pdf_dict_puts_drop(ctx, annot_obj, "Subtype", pdf_new_name(ctx, doc, type_str));
-		pdf_dict_puts_drop(ctx, annot_obj, "Rect", pdf_new_rect(ctx, doc, &rect));
+		pdf_dict_put_drop(ctx, annot_obj, PDF_NAME_Subtype, pdf_new_name(ctx, doc, type_str));
+		pdf_dict_put_drop(ctx, annot_obj, PDF_NAME_Rect, pdf_new_rect(ctx, doc, &rect));
 
 		/* Make printable as default */
-		pdf_dict_puts_drop(ctx, annot_obj, "F", pdf_new_int(ctx, doc, F_Print));
+		pdf_dict_put_drop(ctx, annot_obj, PDF_NAME_F, pdf_new_int(ctx, doc, F_Print));
 
 		annot = fz_malloc_struct(ctx, pdf_annot);
 		annot->page = page;
@@ -194,7 +194,7 @@ pdf_delete_annot(fz_context *ctx, pdf_document *doc, pdf_page *page, pdf_annot *
 	annot->ap = NULL;
 
 	/* Recreate the "Annots" array with this annot removed */
-	old_annot_arr = pdf_dict_gets(ctx, page->me, "Annots");
+	old_annot_arr = pdf_dict_get(ctx, page->me, PDF_NAME_Annots);
 
 	if (old_annot_arr)
 	{
@@ -214,7 +214,7 @@ pdf_delete_annot(fz_context *ctx, pdf_document *doc, pdf_page *page, pdf_annot *
 			if (pdf_is_indirect(ctx, old_annot_arr))
 				pdf_update_object(ctx, doc, pdf_to_num(ctx, old_annot_arr), annot_arr);
 			else
-				pdf_dict_puts(ctx, page->me, "Annots", annot_arr);
+				pdf_dict_put(ctx, page->me, PDF_NAME_Annots, annot_arr);
 
 			if (pdf_is_indirect(ctx, annot->obj))
 				pdf_delete_object(ctx, doc, pdf_to_num(ctx, annot->obj));
@@ -243,7 +243,7 @@ pdf_set_markup_annot_quadpoints(fz_context *ctx, pdf_document *doc, pdf_annot *a
 
 	fz_invert_matrix(&ctm, &annot->page->ctm);
 
-	pdf_dict_puts_drop(ctx, annot->obj, "QuadPoints", arr);
+	pdf_dict_put_drop(ctx, annot->obj, PDF_NAME_QuadPoints, arr);
 
 	for (i = 0; i < n; i++)
 	{
@@ -260,7 +260,7 @@ pdf_set_markup_annot_quadpoints(fz_context *ctx, pdf_document *doc, pdf_annot *a
 
 static void update_rect(fz_context *ctx, pdf_annot *annot)
 {
-	pdf_to_rect(ctx, pdf_dict_gets(ctx, annot->obj, "Rect"), &annot->rect);
+	pdf_to_rect(ctx, pdf_dict_get(ctx, annot->obj, PDF_NAME_Rect), &annot->rect);
 	annot->pagerect = annot->rect;
 	fz_transform_rect(&annot->pagerect, &annot->page->ctm);
 }
@@ -276,7 +276,7 @@ pdf_set_ink_annot_list(fz_context *ctx, pdf_document *doc, pdf_annot *annot, fz_
 
 	fz_invert_matrix(&ctm, &annot->page->ctm);
 
-	pdf_dict_puts_drop(ctx, annot->obj, "InkList", list);
+	pdf_dict_put_drop(ctx, annot->obj, PDF_NAME_InkList, list);
 
 	for (i = 0; i < ncount; i++)
 	{
@@ -320,15 +320,15 @@ pdf_set_ink_annot_list(fz_context *ctx, pdf_document *doc, pdf_annot *annot, fz_
 		rect.y1 += thickness;
 	}
 
-	pdf_dict_puts_drop(ctx, annot->obj, "Rect", pdf_new_rect(ctx, doc, &rect));
+	pdf_dict_put_drop(ctx, annot->obj, PDF_NAME_Rect, pdf_new_rect(ctx, doc, &rect));
 	update_rect(ctx, annot);
 
 	bs = pdf_new_dict(ctx, doc, 1);
-	pdf_dict_puts_drop(ctx, annot->obj, "BS", bs);
-	pdf_dict_puts_drop(ctx, bs, "W", pdf_new_real(ctx, doc, thickness));
+	pdf_dict_put_drop(ctx, annot->obj, PDF_NAME_BS, bs);
+	pdf_dict_put_drop(ctx, bs, PDF_NAME_W, pdf_new_real(ctx, doc, thickness));
 
 	col = pdf_new_array(ctx, doc, 3);
-	pdf_dict_puts_drop(ctx, annot->obj, "C", col);
+	pdf_dict_put_drop(ctx, annot->obj, PDF_NAME_C, col);
 	for (i = 0; i < 3; i++)
 		pdf_array_push_drop(ctx, col, pdf_new_real(ctx, doc, color[i]));
 }
@@ -360,23 +360,23 @@ void pdf_set_text_annot_position(fz_context *ctx, pdf_document *doc, pdf_annot *
 	rect.y1 = pt.y + TEXT_ANNOT_SIZE;
 	fz_transform_rect(&rect, &ctm);
 
-	pdf_dict_puts_drop(ctx, annot->obj, "Rect", pdf_new_rect(ctx, doc, &rect));
+	pdf_dict_put_drop(ctx, annot->obj, PDF_NAME_Rect, pdf_new_rect(ctx, doc, &rect));
 
-	flags = pdf_to_int(ctx, pdf_dict_gets(ctx, annot->obj, "F"));
+	flags = pdf_to_int(ctx, pdf_dict_get(ctx, annot->obj, PDF_NAME_F));
 	flags |= (F_NoZoom|F_NoRotate);
-	pdf_dict_puts_drop(ctx, annot->obj, "F", pdf_new_int(ctx, doc, flags));
+	pdf_dict_put_drop(ctx, annot->obj, PDF_NAME_F, pdf_new_int(ctx, doc, flags));
 
 	update_rect(ctx, annot);
 }
 
 void pdf_set_annot_contents(fz_context *ctx, pdf_document *doc, pdf_annot *annot, char *text)
 {
-	pdf_dict_puts_drop(ctx, annot->obj, "Contents", pdf_new_string(ctx, doc, text, strlen(text)));
+	pdf_dict_put_drop(ctx, annot->obj, PDF_NAME_Contents, pdf_new_string(ctx, doc, text, strlen(text)));
 }
 
 char *pdf_annot_contents(fz_context *ctx, pdf_document *doc, pdf_annot *annot)
 {
-	return pdf_to_str_buf(ctx, pdf_dict_getp(ctx, annot->obj, "Contents"));
+	return pdf_to_str_buf(ctx, pdf_dict_get(ctx, annot->obj, PDF_NAME_Contents));
 }
 
 void pdf_set_free_text_details(fz_context *ctx, pdf_document *doc, pdf_annot *annot, fz_point *pos, char *text, char *font_name, float font_size, float color[3])
@@ -394,19 +394,19 @@ void pdf_set_free_text_details(fz_context *ctx, pdf_document *doc, pdf_annot *an
 
 	fz_invert_matrix(&ctm, &annot->page->ctm);
 
-	dr = pdf_dict_gets(ctx, annot->page->me, "Resources");
+	dr = pdf_dict_get(ctx, annot->page->me, PDF_NAME_Resources);
 	if (!dr)
 	{
 		dr = pdf_new_dict(ctx, doc, 1);
-		pdf_dict_putp_drop(ctx, annot->page->me, "Resources", dr);
+		pdf_dict_put_drop(ctx, annot->page->me, PDF_NAME_Resources, dr);
 	}
 
 	/* Ensure the resource dictionary includes a font dict */
-	form_fonts = pdf_dict_gets(ctx, dr, "Font");
+	form_fonts = pdf_dict_get(ctx, dr, PDF_NAME_Font);
 	if (!form_fonts)
 	{
 		form_fonts = pdf_new_dict(ctx, doc, 1);
-		pdf_dict_puts_drop(ctx, dr, "Font", form_fonts);
+		pdf_dict_put_drop(ctx, dr, PDF_NAME_Font, form_fonts);
 		/* form_fonts is still valid if execution continues past the above call */
 	}
 
@@ -424,10 +424,10 @@ void pdf_set_free_text_details(fz_context *ctx, pdf_document *doc, pdf_annot *an
 		ref = pdf_new_ref(ctx, doc, font);
 		pdf_dict_puts_drop(ctx, form_fonts, nbuf, ref);
 
-		pdf_dict_puts_drop(ctx, font, "Type", pdf_new_name(ctx, doc, "Font"));
-		pdf_dict_puts_drop(ctx, font, "Subtype", pdf_new_name(ctx, doc, "Type1"));
-		pdf_dict_puts_drop(ctx, font, "BaseFont", pdf_new_name(ctx, doc, font_name));
-		pdf_dict_puts_drop(ctx, font, "Encoding", pdf_new_name(ctx, doc, "WinAnsiEncoding"));
+		pdf_dict_put_drop(ctx, font, PDF_NAME_Type, PDF_NAME_Font);
+		pdf_dict_put_drop(ctx, font, PDF_NAME_Subtype, PDF_NAME_Type1);
+		pdf_dict_put_drop(ctx, font, PDF_NAME_BaseFont, pdf_new_name(ctx, doc, font_name));
+		pdf_dict_put_drop(ctx, font, PDF_NAME_Encoding, PDF_NAME_WinAnsiEncoding);
 
 		memcpy(da_info.col, color, sizeof(float)*3);
 		da_info.col_size = 3;
@@ -438,10 +438,10 @@ void pdf_set_free_text_details(fz_context *ctx, pdf_document *doc, pdf_annot *an
 		pdf_fzbuf_print_da(ctx, fzbuf, &da_info);
 
 		da_len = fz_buffer_storage(ctx, fzbuf, &da_str);
-		pdf_dict_puts_drop(ctx, annot->obj, "DA", pdf_new_string(ctx, doc, (char *)da_str, da_len));
+		pdf_dict_put_drop(ctx, annot->obj, PDF_NAME_DA, pdf_new_string(ctx, doc, (char *)da_str, da_len));
 
 		/* FIXME: should convert to WinAnsiEncoding */
-		pdf_dict_puts_drop(ctx, annot->obj, "Contents", pdf_new_string(ctx, doc, text, strlen(text)));
+		pdf_dict_put_drop(ctx, annot->obj, PDF_NAME_Contents, pdf_new_string(ctx, doc, text, strlen(text)));
 
 		font_desc = pdf_load_font(ctx, doc, NULL, font, 0);
 		pdf_measure_text(ctx, font_desc, (unsigned char *)text, strlen(text), &bounds);
@@ -459,7 +459,7 @@ void pdf_set_free_text_details(fz_context *ctx, pdf_document *doc, pdf_annot *an
 		bounds.y0 += page_pos.y;
 		bounds.y1 += page_pos.y;
 
-		pdf_dict_puts_drop(ctx, annot->obj, "Rect", pdf_new_rect(ctx, doc, &bounds));
+		pdf_dict_put_drop(ctx, annot->obj, PDF_NAME_Rect, pdf_new_rect(ctx, doc, &bounds));
 		update_rect(ctx, annot);
 	}
 	fz_always(ctx)