pdf: page label API

5 files changed, 166 insertions, 0 deletions

diff --git a/doc/public/cairo-sections.txt b/doc/public/cairo-sections.txt
index 200c9b21d..51bf48c72 100644
--- a/doc/public/cairo-sections.txt
+++ b/doc/public/cairo-sections.txt
@@ -80,6 +80,7 @@ cairo_pdf_version_to_string
 cairo_pdf_surface_set_size
 cairo_pdf_surface_add_outline
 cairo_pdf_surface_set_metadata
+cairo_pdf_surface_set_page_label
 </SECTION>
 
 <SECTION>
diff --git a/src/cairo-pdf-interchange.c b/src/cairo-pdf-interchange.c
index a84f0ccfa..622f3b3f3 100644
--- a/src/cairo-pdf-interchange.c
+++ b/src/cairo-pdf-interchange.c
@@ -599,6 +599,117 @@ cairo_pdf_interchange_write_outline (cairo_pdf_surface_t *surface)
     return status;
 }
 
+/*
+ * Split a page label into a text prefix and numeric suffix. Leading '0's are
+ * included in the prefix. eg
+ *  "3"     => NULL,    3
+ *  "cover" => "cover", 0
+ *  "A-2"   => "A-",    2
+ *  "A-002" => "A-00",  2
+ */
+static char *
+split_label (const char* label, int *num)
+{
+    int len, i;
+
+    *num = 0;
+    len = strlen (label);
+    if (len == 0)
+	return NULL;
+
+    i = len;
+    while (i > 0 && _cairo_isdigit (label[i-1]))
+	   i--;
+
+    while (i < len && label[i] == '0')
+	i++;
+
+    if (i < len)
+	sscanf (label + i, "%d", num);
+
+    if (i > 0)
+	return strndup (label, i);
+
+    return NULL;
+}
+
+/* strcmp that handles NULL arguments */
+static cairo_bool_t
+strcmp_null (const char *s1, const char *s2)
+{
+    if (s1 && s2)
+	return strcmp (s1, s2) == 0;
+
+    if (!s1 && !s2)
+	return TRUE;
+
+    return FALSE;
+}
+
+static cairo_int_status_t
+cairo_pdf_interchange_write_page_labels (cairo_pdf_surface_t *surface)
+{
+    int num_elems, i;
+    char *label;
+    char *prefix;
+    char *prev_prefix;
+    int num, prev_num;
+    cairo_int_status_t status;
+
+    num_elems = _cairo_array_num_elements (&surface->page_labels);
+    if (num_elems > 0) {
+	surface->page_labels_res = _cairo_pdf_surface_new_object (surface);
+	_cairo_output_stream_printf (surface->output,
+				     "%d 0 obj\n"
+				     "<< /Nums [\n",
+				     surface->page_labels_res.id);
+	prefix = NULL;
+	prev_prefix = NULL;
+	num = 0;
+	prev_num = 0;
+	for (i = 0; i < num_elems; i++) {
+	    _cairo_array_copy_element (&surface->page_labels, i, &label);
+	    if (label) {
+		prefix = split_label (label, &num);
+	    } else {
+		prefix = NULL;
+		num = i + 1;
+	    }
+
+	    if (!strcmp_null (prefix, prev_prefix) || num != prev_num + 1) {
+		_cairo_output_stream_printf (surface->output,  "   %d << ", i);
+
+		if (num)
+		    _cairo_output_stream_printf (surface->output,  "/S /D /St %d ", num);
+
+		if (prefix) {
+		    char *s;
+		    status = _cairo_utf8_to_pdf_string (prefix, &s);
+		    if (unlikely (status))
+			return status;
+
+		    _cairo_output_stream_printf (surface->output,  "/P %s ", s);
+		    free (s);
+		}
+
+		_cairo_output_stream_printf (surface->output,  ">>\n");
+	    }
+	    free (prev_prefix);
+	    prev_prefix = prefix;
+	    prefix = NULL;
+	    prev_num = num;
+	}
+	free (prefix);
+	free (prev_prefix);
+	_cairo_output_stream_printf (surface->output,
+				     "  ]\n"
+				     ">>\n"
+				     "endobj\n");
+    }
+
+    return CAIRO_STATUS_SUCCESS;
+}
+
 static void
 _collect_dest (void *entry, void *closure)
 {
@@ -1077,6 +1188,10 @@ _cairo_pdf_interchange_write_document_objects (cairo_pdf_surface_t *surface)
     if (unlikely (status))
 	return status;
 
+    status = cairo_pdf_interchange_write_page_labels (surface);
+    if (unlikely (status))
+	return status;
+
     status = cairo_pdf_interchange_write_names_dict (surface);
     if (unlikely (status))
 	return status;
diff --git a/src/cairo-pdf-surface-private.h b/src/cairo-pdf-surface-private.h
index a3d45d0ad..960e07cd9 100644
--- a/src/cairo-pdf-surface-private.h
+++ b/src/cairo-pdf-surface-private.h
@@ -323,9 +323,12 @@ struct _cairo_pdf_surface {
     int page_parent_tree; /* -1 if not used */
     cairo_array_t page_annots;
     cairo_bool_t tagged;
+    char *current_page_label;
+    cairo_array_t page_labels;
     cairo_pdf_resource_t outlines_dict_res;
     cairo_pdf_resource_t names_dict_res;
     cairo_pdf_resource_t docinfo_res;
+    cairo_pdf_resource_t page_labels_res;
 
     cairo_surface_t *paginated_surface;
 };
diff --git a/src/cairo-pdf-surface.c b/src/cairo-pdf-surface.c
index 3a125e74f..900055431 100644
--- a/src/cairo-pdf-surface.c
+++ b/src/cairo-pdf-surface.c
@@ -447,8 +447,12 @@ _cairo_pdf_surface_create_for_stream_internal (cairo_output_stream_t	*output,
     surface->page_parent_tree = -1;
     _cairo_array_init (&surface->page_annots, sizeof (cairo_pdf_resource_t));
     surface->tagged = FALSE;
+    surface->current_page_label = NULL;
+    _cairo_array_init (&surface->page_labels, sizeof (char *));
     surface->outlines_dict_res.id = 0;
     surface->names_dict_res.id = 0;
+    surface->docinfo_res.id = 0;
+    surface->page_labels_res.id = 0;
 
     surface->paginated_surface =  _cairo_paginated_surface_create (
 	                                  &surface->base,
@@ -806,6 +810,28 @@ cairo_pdf_surface_set_metadata (cairo_surface_t      *surface,
 	status = _cairo_surface_set_error (surface, status);
 }
 
+/**
+ * cairo_pdf_surface_set_page_label:
+ * @surface: a PDF #cairo_surface_t
+ * @utf8: The page label.
+ *
+ * Set page label for the current page.
+ *
+ * Since: 1.16
+ **/
+void
+cairo_pdf_surface_set_page_label (cairo_surface_t *surface,
+                                  const char      *utf8)
+{
+    cairo_pdf_surface_t *pdf_surface = NULL; /* hide compiler warning */
+
+    if (! _extract_pdf_surface (surface, &pdf_surface))
+	return;
+
+    free (pdf_surface->current_page_label);
+    pdf_surface->current_page_label = utf8 ? strdup (utf8) : NULL;
+}
+
 static void
 _cairo_pdf_surface_clear (cairo_pdf_surface_t *surface)
 {
@@ -2158,6 +2184,7 @@ _cairo_pdf_surface_finish (void *abstract_surface)
     cairo_status_t status, status2;
     int size, i;
     cairo_pdf_jbig2_global_t *global;
+    char *label;
 
     status = surface->base.status;
     if (status == CAIRO_STATUS_SUCCESS)
@@ -2255,6 +2282,13 @@ _cairo_pdf_surface_finish (void *abstract_surface)
     }
     _cairo_array_fini (&surface->jbig2_global);
 
+    size = _cairo_array_num_elements (&surface->page_labels);
+    for (i = 0; i < size; i++) {
+	_cairo_array_copy_element (&surface->page_labels, i, &label);
+	free (label);
+    }
+    _cairo_array_fini (&surface->page_labels);
+
     _cairo_array_truncate (&surface->page_surfaces, 0);
 
     _cairo_surface_clipper_reset (&surface->clipper);
@@ -4783,6 +4817,9 @@ _cairo_pdf_surface_show_page (void *abstract_surface)
     cairo_pdf_surface_t *surface = abstract_surface;
     cairo_int_status_t status;
 
+    status = _cairo_array_append (&surface->page_labels, &surface->current_page_label);
+    surface->current_page_label = NULL;
+
     status = _cairo_pdf_interchange_end_page_content (surface);
     if (unlikely (status))
 	return status;
@@ -6173,6 +6210,12 @@ _cairo_pdf_surface_write_catalog (cairo_pdf_surface_t *surface)
 				     surface->outlines_dict_res.id);
     }
 
+    if (surface->page_labels_res.id != 0) {
+	_cairo_output_stream_printf (surface->output,
+				     "   /PageLabels %d 0 R\n",
+				     surface->page_labels_res.id);
+    }
+
     if (surface->names_dict_res.id != 0) {
 	_cairo_output_stream_printf (surface->output,
 				     "   /Names %d 0 R\n",
diff --git a/src/cairo-pdf.h b/src/cairo-pdf.h
index 0589ba53a..9bf69fedd 100644
--- a/src/cairo-pdf.h
+++ b/src/cairo-pdf.h
@@ -144,6 +144,10 @@ cairo_pdf_surface_set_metadata (cairo_surface_t	     *surface,
 				cairo_pdf_metadata_t  metadata,
                                 const char           *utf8);
 
+void
+cairo_pdf_surface_set_page_label (cairo_surface_t *surface,
+                                  const char      *utf8);
+
 CAIRO_END_DECLS
 
 #else  /* CAIRO_HAS_PDF_SURFACE */