[freetype2] master 2c40559 45/68: Meson: Fix dependency lookup and generate ftconfig.h

[Werner Lemberg]

branch: master
commit 2c40559609c102a934c1f0c5ee7ccb790fc887dc
Author: Xavier Claessens <xavier.claessens@collabora.com>
Commit: Werner Lemberg <wl@gnu.org>

    Meson: Fix dependency lookup and generate ftconfig.h
    
    [meson] Fix dependency lookup and generate `ftconfig.h`.
    
    - zlib: If not found on the system, meson can build it as a
      subproject.  We thus never use the (outdated) zlib support that
      comes with FreeType.  Doing so has the additional advantage that
      the zlib code can be shared with other projects like GLib if both
      are subprojects of an application.
    - harfbuzz: Build as a subproject if not found on the system.
    - 'QUESTION: What if the compiler doesn't support `-D` but uses `/D`
      instead as on Windows?'  Answer: Meson translate arguments for us.
    - visibility: Replace self-made code with meson-specific solution.
    
    * meson.build (ft2_defines): Rewrite logic to set and handle it.
    (process_header_command): New variable, previously called
    `ftoption_command`.
    (ftoption_command, ftconfig_command): New variables.
    (zlib_option): Removed.
    (zlib_dep): New variable.
    (ft2_deps): Updated.
    (harfbuzz_dep): Updated.
    (ftconfig_h_in, ftconfig_h): New variables.
    (ft2_sources): Updated.
    (ft2_lib): Updated, handle visibility.
    (summary): Updted.
    
    * meson_options.txt (zlib): Updated.
---
 ChangeLog         | 29 +++++++++++++++++
 meson.build       | 93 +++++++++++++++++++++++++++----------------------------
 meson_options.txt |  3 +-
 3 files changed, 75 insertions(+), 50 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index e7095d8..6c37127 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,34 @@
 2021-02-09  Xavier Claessens  <xavier.claessens@collabora.com>
 
+       [meson] Fix dependency lookup and generate `ftconfig.h`.
+
+       - zlib: If not found on the system, meson can build it as a
+         subproject.  We thus never use the (outdated) zlib support that
+         comes with FreeType.  Doing so has the additional advantage that
+         the zlib code can be shared with other projects like GLib if both
+         are subprojects of an application.
+       - harfbuzz: Build as a subproject if not found on the system.
+       - 'QUESTION: What if the compiler doesn't support `-D` but uses `/D`
+         instead as on Windows?'  Answer: Meson translate arguments for us.
+       - visibility: Replace self-made code with meson-specific solution.
+
+       * meson.build (ft2_defines): Rewrite logic to set and handle it.
+       (process_header_command): New variable, previously called
+       `ftoption_command`.
+       (ftoption_command, ftconfig_command): New variables.
+       (zlib_option): Removed.
+       (zlib_dep): New variable.
+       (ft2_deps): Updated.
+       (harfbuzz_dep): Updated.
+       (ftconfig_h_in, ftconfig_h): New variables.
+       (ft2_sources): Updated.
+       (ft2_lib): Updated, handle visibility.
+       (summary): Updted.
+
+       * meson_options.txt (zlib): Updated.
+
+2021-02-09  Xavier Claessens  <xavier.claessens@collabora.com>
+
        * meson.build: Fix resource compilation on Windows.
 
        This is copied from GStreamer's meson port of FreeType.
diff --git a/meson.build b/meson.build
index df61dec..0116572 100644
--- a/meson.build
+++ b/meson.build
@@ -170,7 +170,7 @@ ft2_config_headers = files([
   'include/freetype/config/public-macros.h',
 ])
 
-ft2_defines = []
+ft2_defines = ['-DFT2_BUILD_LIBRARY=1']
 
 
 # System support file.
@@ -182,13 +182,6 @@ has_unistd_h = cc.has_header('unistd.h')
 has_fcntl_h = cc.has_header('fcntl.h')
 has_sys_mman_h = cc.has_header('sys/mman.h')
 
-if has_unistd_h
-  ft2_defines += ['-DHAVE_UNISTD_H=1']
-endif
-if has_fcntl_h
-  ft2_defines += ['-DHAVE_FCNTL_H']
-endif
-
 mmap_option = get_option('mmap')
 if mmap_option.auto()
   use_mmap = has_unistd_h and has_fcntl_h and has_sys_mman_h
@@ -229,27 +222,24 @@ ft2_deps = []
 
 # Generate `ftoption.h` based on available dependencies.
 
-ftoption_command = [python_exe,
+process_header_command = [python_exe,
   files('builds/meson/process_ftoption_h.py'),
   '@INPUT@', '--output=@OUTPUT@']
+ftoption_command = process_header_command
+
 
 # GZip support
-have_zlib='no'
-zlib_option = get_option('zlib')
-if zlib_option == 'disabled'
-  ftoption_command += ['--disable=FT_CONFIG_OPTION_USE_ZLIB']
-else
-  have_zlib='yes'
-  ftoption_command += ['--enable=FT_CONFIG_OPTION_USE_ZLIB']
-  if zlib_option == 'builtin'
-    ftoption_command += ['--disable=FT_CONFIG_OPTION_SYSTEM_ZLIB']
-  else
-    # Probe for the system version.
-    zlib_system = dependency('zlib', required: zlib_option == 'system')
-    ft2_deps += [zlib_system]
-    ftoption_command += ['--enable=FT_CONFIG_OPTION_SYSTEM_ZLIB']
-  endif
+zlib_dep = dependency('zlib', required: get_option('zlib'),
+  fallback: ['zlib', 'zlib_dep'])
+if zlib_dep.found()
+  ftoption_command += [
+    '--enable=FT_CONFIG_OPTION_USE_ZLIB',
+    '--enable=FT_CONFIG_OPTION_SYSTEM_ZLIB',
+  ]
   ft2_sources += files(['src/gzip/ftgzip.c',])
+  ft2_deps += [zlib_dep]
+else
+  ftoption_command += ['--disable=FT_CONFIG_OPTION_USE_ZLIB']
 endif
 
 # BZip2 support
@@ -270,7 +260,10 @@ endif
 # Harfbuzz support
 harfbuzz_dep = dependency('harfbuzz',
                  version: '>= 2.0.0',
-                 required: get_option('harfbuzz'))
+                 required: get_option('harfbuzz'),
+                 fallback: ['harfbuzz', 'libharfbuzz_dep'],
+                 default_options : ['freetype=disabled',
+                                    'fontconfig=disabled'])
 if harfbuzz_dep.found()
   ftoption_command += ['--enable=FT_CONFIG_OPTION_USE_HARFBUZZ']
   ft2_deps += [harfbuzz_dep]
@@ -292,39 +285,43 @@ ftoption_h = custom_target('ftoption.h',
   install_dir: 'include/freetype2/freetype/config',
 )
 ft2_sources += ftoption_h
-
-
-# QUESTION: What if the compiler doesn't support `-D` but uses `/D` instead
-# as on Windows?
-#
-# Other build systems have something like c_defines to list defines in a
-# more portable way.  For now assume the compiler supports `-D` (hint: Visual
-# Studio does).
-ft2_defines += ['-DFT2_BUILD_LIBRARY=1']
+ft2_defines += ['-DFT_CONFIG_OPTIONS_H=<ftoption.h>']
 
 if host_machine.system() == 'windows'
   ft2_defines += ['-DDLL_EXPORT=1']
 endif
 
+# Generate `ftconfig.h`
 
-# Ensure that the `ftoption.h` file generated above will be used to build
-# FreeType.  Unfortunately, and very surprisingly, configure_file() does not
-# support putting the output file in a sub-directory, so we have to override
-# the default which is `<freetype/config/ftoption.h>`.
-#
-# It would be cleaner to generate the file directly into
-# `${MESON_BUILD_DIR}/freetype/config/ftoption.h`.  See
-# 'https://github.com/mesonbuild/meson/issues/2320' for details.
-ft2_defines += ['-DFT_CONFIG_OPTIONS_H=<ftoption.h>']
+ftconfig_command = process_header_command
+if has_unistd_h
+  ftconfig_command += '--enable=HAVE_UNISTD_H'
+endif
+if has_fcntl_h
+  ftconfig_command += '--enable=HAVE_FCNTL_H'
+endif
 
-ft2_c_args = ft2_defines
-if cc.has_function_attribute('visibility:hidden')
-  ft2_c_args += ['-fvisibility=hidden']
+if host_machine.system() in ['linux', 'darwin', 'cygwin']
+  ftconfig_h_in = files('builds/unix/ftconfig.h.in')
+else
+  ftconfig_h_in = files('include/freetype/config/ftconfig.h')
 endif
 
+ftconfig_h = custom_target('ftconfig.h',
+  input: ftconfig_h_in,
+  output: 'ftconfig.h',
+  command: ftconfig_command,
+  install: true,
+  install_dir: 'include/freetype2/freetype/config',
+)
+ft2_sources += ftconfig_h
+ft2_defines += ['-DFT_CONFIG_CONFIG_H=<ftconfig.h>']
+
+
 ft2_lib = library('freetype',
   sources: ft2_sources + [ftmodule_h],
-  c_args: ft2_c_args,
+  c_args: ft2_defines,
+  gnu_symbol_visibility: 'hidden',
   include_directories: ft2_includes,
   dependencies: ft2_deps,
   install: true,
@@ -378,7 +375,7 @@ gen_docs = custom_target('freetype2 reference 
documentation',
 
 
 summary({'OS': host_machine.system(),
-         'Zlib': have_zlib,
+         'Zlib': zlib_dep.found() ? 'yes' : 'no',
          'Bzip2': bzip2_dep.found() ? 'yes' : 'no',
          'Png': libpng_dep.found() ? 'yes' : 'no',
          'Harfbuzz': harfbuzz_dep.found() ? 'yes' : 'no',
diff --git a/meson_options.txt b/meson_options.txt
index 301acdc..f0fc50a 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -13,8 +13,7 @@
 
 
 option('zlib',
-  type: 'combo',
-  choices: ['disabled', 'auto', 'builtin', 'system'],
+  type: 'feature',
   value: 'auto',
   description: 'Support reading gzip-compressed font files.')