[babl] Add linker script for symbols export

[Øyvind Kolås <ok src gnome org>]

commit e617352e3ed19fe00091e94a005213a922cd60ec
Author: Félix Piédallu <felix piedallu me>
Date:   Tue Nov 28 15:53:04 2017 +0100

    Add linker script for symbols export

 babl.map         |   76 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 babl/meson.build |    1 +
 meson.build      |    3 ++
 3 files changed, 80 insertions(+), 0 deletions(-)
---
diff --git a/babl.map b/babl.map
new file mode 100644
index 0000000..bacbbea
--- /dev/null
+++ b/babl.map
@@ -0,0 +1,76 @@
+V0_1_0 {
+    global:
+        babl_component;
+        babl_component_new;
+        babl_conversion_get_destination_space;
+        babl_conversion_get_source_space;
+        babl_conversion_new;
+        babl_cpu_accel_get_support;
+        babl_exit;
+        babl_fast_fish;
+        babl_fish;
+        babl_format;
+        babl_format_exists;
+        babl_format_get_bytes_per_pixel;
+        babl_format_get_model;
+        babl_format_get_n_components;
+        babl_format_get_space;
+        babl_format_get_type;
+        babl_format_has_alpha;
+        babl_format_is_format_n;
+        babl_format_is_palette;
+        babl_format_n;
+        babl_format_new;
+        babl_format_with_space;
+        babl_free;
+        babl_get_name;
+        babl_get_name;
+        babl_get_user_data;
+        babl_get_version;
+        babl_icc_make_space;
+        babl_icc_get_key;
+        babl_init;
+        babl_introspect;
+        babl_malloc;
+        babl_model;
+        babl_model_new;
+        babl_new_palette;
+        babl_palette_reset;
+        babl_palette_set_palette;
+        babl_process;
+        babl_process;
+        babl_sampling;
+        babl_set_user_data;
+        babl_space;
+        babl_space_from_xyz;
+        babl_space_get_rgbtoxyz;
+        babl_space_to_xyz;
+        babl_ticks;
+        babl_type;
+        babl_type_new;
+        babl_space_to_icc;
+        babl_db_exist_by_name;
+        babl_db_find;
+        babl_db_init;
+        babl_db_exist_by_id;
+        babl_db_each;
+        babl_formats_count;
+        babl_format_class_for_each;
+        babl_model_class_for_each;
+        babl_type_class_for_each;
+        babl_conversion_class_for_each;
+        babl_set_extender;
+        babl_extension_quiet_log;
+        babl_fish_path;
+        babl_extender;
+        babl_class_name;
+        babl_sanity;
+        babl_type_is_symmetric;
+        babl_model_is_symmetric;
+        babl_fish_db;
+        babl_polynomial_approximate_gamma;
+        babl_backtrack;
+
+    local:
+        *;
+};
diff --git a/babl/meson.build b/babl/meson.build
index 5d783eb..c335d63 100644
--- a/babl/meson.build
+++ b/babl/meson.build
@@ -84,6 +84,7 @@ babl = library('babl',
   c_args:   [ '-DLIBDIR="' + get_option('libdir') + '"', ],
   cpp_args: [ '-DLIBDIR="' + get_option('libdir') + '"', ],
   link_with: [ babl_base, ],
+  link_args: [ '-Wl,--version-script,' + version_script, ],
   dependencies: [ math, thread, dl, ],
   install: true,
   version: so_version,
diff --git a/meson.build b/meson.build
index 01cf491..3ea038d 100644
--- a/meson.build
+++ b/meson.build
@@ -240,6 +240,9 @@ configure_file(
 # Subdirs
 
 rootInclude = include_directories('.')
+version_script = join_paths(
+  meson.source_root(), meson.current_source_dir(), 'babl.map'
+)
 
 subdir('babl')
 subdir('extensions')