Merge pull request #4046 from harfbuzz/hb-features-docs

[doc] Try to fix generating hb-features docs

docs/harfbuzz-docs.xml

@@ -56,6 +56,7 @@
         <xi:include href="xml/hb-blob.xml"/>
         <xi:include href="xml/hb-buffer.xml"/>
         <xi:include href="xml/hb-common.xml"/>
+        <xi:include href="xml/hb-features.xml"/>
         <xi:include href="xml/hb-draw.xml"/>
         <xi:include href="xml/hb-paint.xml"/>
         <xi:include href="xml/hb-deprecated.xml"/>

docs/harfbuzz-sections.txt

@@ -166,16 +166,6 @@ HB_TAG_MAX_SIGNED
 HB_LANGUAGE_INVALID
 HB_FEATURE_GLOBAL_END
 HB_FEATURE_GLOBAL_START
-HB_HAS_CAIRO
-HB_HAS_CORETEXT
-HB_HAS_DIRECTWRITE
-HB_HAS_FREETYPE
-HB_HAS_GDI
-HB_HAS_GLIB
-HB_HAS_GOBJECT
-HB_HAS_GRAPHITE
-HB_HAS_ICU
-HB_HAS_UNISCRIBE
 <SUBSECTION Private>
 HB_BEGIN_DECLS
 HB_END_DECLS
@@ -194,6 +184,20 @@ HB_DEPRECATED
 HB_DEPRECATED_FOR
 </SECTION>
 
+<SECTION>
+<FILE>hb-features</FILE>
+HB_HAS_CAIRO
+HB_HAS_CORETEXT
+HB_HAS_DIRECTWRITE
+HB_HAS_FREETYPE
+HB_HAS_GDI
+HB_HAS_GLIB
+HB_HAS_GOBJECT
+HB_HAS_GRAPHITE
+HB_HAS_ICU
+HB_HAS_UNISCRIBE
+</SECTION>
+
 <SECTION>
 <FILE>hb-draw</FILE>
 hb_draw_funcs_create

docs/meson.build

@@ -36,6 +36,7 @@ html_images = [
 ]
 
 ignore_headers = [
+  'hb-features.h',
   'hb-gobject.h',
   'hb-gobject-enums.h',
   'hb-gobject-enums-tmp.h',

src/hb-features.h.in

@@ -27,6 +27,14 @@
 
 HB_BEGIN_DECLS
 
+/**
+ * SECTION: hb-features
+ * @title: hb-features
+ * @short_description: Feature detection
+ * @include: hb-features.h
+ *
+ * Macros for detecting optional HarfBuzz features at build time.
+ **/
 
 /**
  * HB_HAS_CAIRO:

src/meson.build

@@ -422,24 +422,16 @@ harfbuzz_deps = [thread_dep, m_dep] + harfbuzz_extra_deps
 
 libharfbuzz_link_language = 'c'
 
-hb_features = configuration_data()
-
 if conf.get('HAVE_FREETYPE', 0) == 1
   hb_sources += hb_ft_sources
   hb_headers += hb_ft_headers
   harfbuzz_deps += [freetype_dep]
-  hb_features.set('HB_HAS_FREETYPE', 1)
 endif
 
 if conf.get('HAVE_GLIB', 0) == 1
   hb_sources += hb_glib_sources
   hb_headers += hb_glib_headers
   harfbuzz_deps += [glib_dep]
-  hb_features.set('HB_HAS_GLIB', 1)
-endif
-
-if conf.get('HAVE_GOBJECT', 0) == 1
-  hb_features.set('HB_HAS_GOBJECT', 1)
 endif
 
 # We set those here to not include the sources below that are of no use to
@@ -451,20 +443,17 @@ if conf.get('HAVE_GDI', 0) == 1
   hb_sources += hb_gdi_sources
   hb_headers += hb_gdi_headers
   harfbuzz_deps += gdi_uniscribe_deps
-  hb_features.set('HB_HAS_GDI', 1)
 endif
 
 if conf.get('HAVE_GRAPHITE2', 0) == 1
   hb_sources += hb_graphite2_sources
   hb_headers += hb_graphite2_headers
   harfbuzz_deps += [graphite2_dep, graphite_dep]
-  hb_features.set('HB_HAS_GRAPHITE', 1)
 endif
 
 if conf.get('HAVE_UNISCRIBE', 0) == 1
   hb_sources += hb_uniscribe_sources
   hb_headers += hb_uniscribe_headers
-  hb_features.set('HB_HAS_UNISCRIBE', 1)
 endif
 
 if conf.get('HAVE_DIRECTWRITE', 0) == 1
@@ -472,36 +461,58 @@ if conf.get('HAVE_DIRECTWRITE', 0) == 1
   hb_headers += hb_directwrite_headers
   # hb-directwrite needs a C++ linker
   libharfbuzz_link_language = 'cpp'
-  hb_features.set('HB_HAS_DIRECTWRITE', 1)
 endif
 
 if conf.get('HAVE_CORETEXT', 0) == 1
   hb_sources += hb_coretext_sources
   hb_headers += hb_coretext_headers
   harfbuzz_deps += coretext_deps
-  hb_features.set('HB_HAS_CORETEXT', 1)
 endif
 
 have_icu = conf.get('HAVE_ICU', 0) == 1
 have_icu_builtin = conf.get('HAVE_ICU_BUILTIN', 0) == 1
-
 if have_icu and have_icu_builtin
   hb_sources += hb_icu_sources
   hb_headers += hb_icu_headers
   harfbuzz_deps += [icu_dep]
-  hb_features.set('HB_HAS_ICU', 1)
 endif
 
-if conf.get('HAVE_CAIRO', 0) == 1
-  hb_features.set('HB_HAS_CAIRO', 1)
-endif
+features = [
+  'CAIRO',
+  'CORETEXT',
+  'DIRECTWRITE',
+  'FREETYPE',
+  'GDI',
+  'GLIB',
+  'GOBJECT',
+  'GRAPHITE',
+  'ICU',
+  'UNISCRIBE',
+]
 
+hb_enabled_features = configuration_data()
+hb_supported_features = configuration_data()
+foreach feature : features
+  key = 'HB_HAS_@0@'.format(feature)
+  hb_enabled_features.set(key, conf.get('HAVE_@0@'.format(feature), false))
+  hb_supported_features.set(key, 1)
+endforeach
+
+# The enabled features. This file is installed.
 hb_features_h = configure_file(input: 'hb-features.h.in',
                                output: 'hb-features.h',
-                               configuration: hb_features,
+                               configuration: hb_enabled_features,
                                install: true,
                                install_dir: get_option('includedir') / meson.project_name())
 
+# This file is generated to convince gtk-doc to generate documentation for all
+# HB_HAS_* macros, whether they are enabled for the current build or not.
+# This file should not be installed.
+hb_supported_features_h = configure_file(input: 'hb-features.h.in',
+                               output: 'hb-supported-features.h',
+                               configuration: hb_supported_features,
+                               install: false)
+
 # Base and default-included sources and headers
 
 # harfbuzz