[ghex] docs: Add missing directory.

[Logan Rathbone <larathbone src gnome org>]

commit 6c804688e37d545efd2db2dc4f1dbf73c1418586
Author: Logan Rathbone <poprocks gmail com>
Date:   Mon Dec 27 16:45:40 2021 -0500

    docs: Add missing directory.

 docs/GtkHex.toml.in | 45 +++++++++++++++++++++++++++++++++++++++++++++
 docs/meson.build    | 49 +++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 94 insertions(+)
---
diff --git a/docs/GtkHex.toml.in b/docs/GtkHex.toml.in
new file mode 100644
index 0000000..2010d8b
--- /dev/null
+++ b/docs/GtkHex.toml.in
@@ -0,0 +1,45 @@
+[library]
+version = "@version@"
+description = "Hex widget and document backend for GTK"
+authors = "The GHex authors"
+license = "GPL-2.1-or-later"
+browse_url = "https://gitlab.gnome.org/GNOME/ghex/";
+repository_url = "https://gitlab.gnome.org/GNOME/ghex.git";
+website_url = "https://gitlab.gnome.org/GNOME/ghex/";
+dependencies = [ "GObject-2.0", "Pango-1.0", "Gdk-4.0", "Gtk-4.0" ]
+search_index = true
+
+  [dependencies."GObject-2.0"]
+  name = "GObject"
+  description = "The base type system library"
+  docs_url = "https://docs.gtk.org/gobject/";
+
+  [dependencies."GLib-2.0"]
+  name = "GLib"
+  description = "The base type system library"
+  docs_url = "https://docs.gtk.org/glib/";
+
+  [dependencies."Gio-2.0"]
+  name = "GIO"
+  description = "GObject Interfaces and Objects, Networking, IPC, and I/O"
+  docs_url = "https://docs.gtk.org/gio/";
+
+  [dependencies."Pango-1.0"]
+  name = "Pango"
+  description = "Text shaping and rendering"
+  docs_url = "https://docs.gtk.org/Pango/";
+
+  [dependencies."Gdk-Pixbuf-2.0"]
+  name = "GdkPixbuf"
+  description = "Image loading library"
+  docs_url = "https://docs.gtk.org/gdk-pixbuf/";
+
+  [dependencies."Gdk-4.0"]
+  name = "GDK"
+  description = "The GTK windowing system abstraction"
+  docs_url = "https://docs.gtk.org/gdk4/";
+
+  [dependencies."Gtk-4.0"]
+  name = "GTK"
+  description = "The GTK toolkit"
+  docs_url = "https://docs.gtk.org/gtk4/";
diff --git a/docs/meson.build b/docs/meson.build
new file mode 100644
index 0000000..ecbbc08
--- /dev/null
+++ b/docs/meson.build
@@ -0,0 +1,49 @@
+if build_gtk_doc and not get_option('introspection').allowed()
+  error('API reference requires introspection.')
+endif
+
+toml_conf = configuration_data()
+toml_conf.set('version', meson.project_version())
+
+gidocgen = find_program('gi-docgen', required: get_option('gtk_doc'))
+gir_apiname = 'libgtkhex-@0@.0'.format(libgtkhex_version_major)
+
+gidocgen_common_args = [
+  '--quiet',
+  '--no-namespace-dir',
+]
+
+if get_option('werror')
+  gidocgen_common_args += ['--fatal-warnings']
+endif
+
+docs_dir = join_paths(ghex_datadir, 'doc')
+
+if get_option('gtk_doc')
+  gtkhex_toml = configure_file(
+    input: 'GtkHex.toml.in',
+    output: 'GtkHex.toml',
+    configuration: toml_conf,
+    install: true,
+    install_dir: join_paths(docs_dir, gir_apiname),
+  )
+
+  docs_cmd = [
+      gidocgen,
+      'generate',
+      gidocgen_common_args,
+      '--config=@INPUT0@',
+      '--output-dir=@OUTPUT@',
+      '--content-dir=@0@'.format(meson.current_source_dir()),
+      '@INPUT1@',
+  ]
+
+  custom_target('libgtkhex-doc',
+    input: [ gtkhex_toml, gtkhex_gir[0] ],
+    output: gir_apiname,
+    command: docs_cmd,
+    build_by_default: true,
+    install: true,
+    install_dir: join_paths(docs_dir, gir_apiname),
+  )
+endif