[pango/private-vfuncs: 4/5] Add pango_font_get_languages

[Matthias Clasen <matthiasc src gnome org>]

commit 3555527ce39359e19594fc23c825e17f483f824e
Author: Matthias Clasen <mclasen redhat com>
Date:   Sat Jul 31 13:05:31 2021 -0400

    Add pango_font_get_languages
    
    Start using private vfuncs for PangoFont, and use it
    to replace the recently introduced pango_fc_font_get_languages
    with a frontend api.

 pango/fonts.c              | 44 +++++++++++++++++++++++++++++++++++++++++++-
 pango/pango-font-private.h |  4 ++++
 pango/pango-font.h         |  3 +++
 pango/pangofc-font.c       | 19 +++++++++++++++++--
 pango/pangofc-font.h       |  3 ++-
 5 files changed, 69 insertions(+), 4 deletions(-)
---
diff --git a/pango/fonts.c b/pango/fonts.c
index 79cf1251..27a973f8 100644
--- a/pango/fonts.c
+++ b/pango/fonts.c
@@ -1688,7 +1688,13 @@ typedef struct {
   hb_font_t *hb_font;
 } PangoFontPrivate;
 
-G_DEFINE_ABSTRACT_TYPE_WITH_PRIVATE (PangoFont, pango_font, G_TYPE_OBJECT)
+#define PANGO_FONT_GET_CLASS_PRIVATE(font) ((PangoFontClassPrivate *) \
+   g_type_class_get_private ((GTypeClass *) PANGO_FONT_GET_CLASS (font), \
+                            PANGO_TYPE_FONT))
+
+G_DEFINE_ABSTRACT_TYPE_WITH_CODE (PangoFont, pango_font, G_TYPE_OBJECT,
+                                  G_ADD_PRIVATE (PangoFont)
+                                  g_type_add_class_private (g_define_type_id, sizeof 
(PangoFontClassPrivate)))
 
 static void
 pango_font_finalize (GObject *object)
@@ -1701,12 +1707,22 @@ pango_font_finalize (GObject *object)
   G_OBJECT_CLASS (pango_font_parent_class)->finalize (object);
 }
 
+static PangoLanguage **
+pango_font_default_get_languages (PangoFont *font)
+{
+  return NULL;
+}
+
 static void
 pango_font_class_init (PangoFontClass *class G_GNUC_UNUSED)
 {
   GObjectClass *object_class = G_OBJECT_CLASS (class);
 
   object_class->finalize = pango_font_finalize;
+
+  pclass = g_type_class_get_private ((GTypeClass *) class, PANGO_TYPE_FONT);
+
+  pclass->get_languages = pango_font_default_get_languages;
 }
 
 static void
@@ -2625,3 +2641,29 @@ pango_font_get_features (PangoFont    *font,
   if (PANGO_FONT_GET_CLASS (font)->get_features)
     PANGO_FONT_GET_CLASS (font)->get_features (font, features, len, num_features);
 }
+
+/**
+ * pango_font_get_languages:
+ * @font: a `PangoFont`
+ *
+ * Returns the languages that are supported by @font.
+ *
+ * If the font backend does not provide this information,
+ * %NULL is returned. For the fontconfig backend, this
+ * corresponds to the FC_LANG member of the FcPattern.
+ *
+ * The returned array is only valid as long as the font
+ * and its fontmap are valid.
+ *
+ * Returns: (transfer none) (nullable): a %NULL-terminated
+ *   array of `PangoLanguage`*
+ *
+ * Since: 1.50
+ */
+PangoLanguage **
+pango_font_get_languages (PangoFont *font)
+{
+  PangoFontClassPrivate *pclass = PANGO_FONT_GET_CLASS_PRIVATE (font);
+
+  return pclass->get_languages (font);
+}
diff --git a/pango/pango-font-private.h b/pango/pango-font-private.h
index befa1b94..54de2c01 100644
--- a/pango/pango-font-private.h
+++ b/pango/pango-font-private.h
@@ -33,6 +33,10 @@ G_BEGIN_DECLS
 PANGO_AVAILABLE_IN_ALL
 PangoFontMetrics *pango_font_metrics_new (void);
 
+typedef struct {
+  PangoLanguage ** (* get_languages) (PangoFont *font);
+} PangoFontClassPrivate;
+
 G_END_DECLS
 
 #endif /* __PANGO_FONT_PRIVATE_H__ */
diff --git a/pango/pango-font.h b/pango/pango-font.h
index 13f8a222..498338b2 100644
--- a/pango/pango-font.h
+++ b/pango/pango-font.h
@@ -601,6 +601,9 @@ void                  pango_font_get_features      (PangoFont        *font,
 PANGO_AVAILABLE_IN_1_44
 hb_font_t *           pango_font_get_hb_font       (PangoFont        *font);
 
+PANGO_AVAILABLE_IN_1_50
+PangoLanguage **      pango_font_get_languages     (PangoFont        *font);
+
 /**
  * PANGO_GLYPH_EMPTY:
  *
diff --git a/pango/pangofc-font.c b/pango/pangofc-font.c
index cd063854..2546e663 100644
--- a/pango/pangofc-font.c
+++ b/pango/pangofc-font.c
@@ -21,6 +21,7 @@
 
 #include "config.h"
 
+#include "pango-font-private.h"
 #include "pangofc-font-private.h"
 #include "pangofc-fontmap.h"
 #include "pangofc-private.h"
@@ -69,6 +70,7 @@ static void                  pango_fc_font_get_features (PangoFont        *font,
                                                          guint             len,
                                                          guint            *num_features);
 static hb_font_t *           pango_fc_font_create_hb_font (PangoFont        *font);
+static PangoLanguage **     _pango_fc_font_get_languages  (PangoFont        *font);
 
 #define PANGO_FC_FONT_LOCK_FACE(font)  (PANGO_FC_FONT_GET_CLASS (font)->lock_face (font))
 #define PANGO_FC_FONT_UNLOCK_FACE(font)        (PANGO_FC_FONT_GET_CLASS (font)->unlock_face (font))
@@ -81,6 +83,7 @@ pango_fc_font_class_init (PangoFcFontClass *class)
 {
   GObjectClass *object_class = G_OBJECT_CLASS (class);
   PangoFontClass *font_class = PANGO_FONT_CLASS (class);
+  PangoFontClassPrivate *pclass;
 
   class->has_char = pango_fc_font_real_has_char;
   class->get_glyph = pango_fc_font_real_get_glyph;
@@ -98,6 +101,10 @@ pango_fc_font_class_init (PangoFcFontClass *class)
   font_class->create_hb_font = pango_fc_font_create_hb_font;
   font_class->get_features = pango_fc_font_get_features;
 
+  pclass = g_type_class_get_private ((GTypeClass *) class, PANGO_TYPE_FONT);
+
+  pclass->get_languages = _pango_fc_font_get_languages;
+
   /**
    * PangoFcFont:pattern:
    *
@@ -1046,18 +1053,26 @@ done:
  *   array of `PangoLanguage`*
  *
  * Since: 1.48
+ * Deprecated: 1.50: Use pango_font_get_language()
  */
 PangoLanguage **
 pango_fc_font_get_languages (PangoFcFont *font)
 {
+  return pango_font_get_languages (PANGO_FONT (font));
+}
+
+static PangoLanguage **
+_pango_fc_font_get_languages (PangoFont *font)
+{
+  PangoFcFont * fcfont = PANGO_FC_FONT (font);
   PangoFcFontMap *fontmap;
   PangoLanguage **languages;
 
-  fontmap = g_weak_ref_get ((GWeakRef *) &font->fontmap);
+  fontmap = g_weak_ref_get ((GWeakRef *) &fcfont->fontmap);
   if (!fontmap)
     return NULL;
 
-  languages  = _pango_fc_font_map_get_languages (fontmap, font);
+  languages  = _pango_fc_font_map_get_languages (fontmap, fcfont);
   g_object_unref (fontmap);
 
   return languages;
diff --git a/pango/pangofc-font.h b/pango/pangofc-font.h
index b4aa399e..89b0cc79 100644
--- a/pango/pangofc-font.h
+++ b/pango/pangofc-font.h
@@ -95,7 +95,8 @@ gboolean   pango_fc_font_has_char          (PangoFcFont      *font,
 PANGO_AVAILABLE_IN_1_4
 guint      pango_fc_font_get_glyph         (PangoFcFont      *font,
                                             gunichar          wc);
-PANGO_AVAILABLE_IN_1_48
+
+PANGO_DEPRECATED_IN_1_50_FOR(pango_font_get_language)
 PangoLanguage **
            pango_fc_font_get_languages     (PangoFcFont      *font);