build: Add Meson build files

Meson is a Python-based build system that generates build rules of
Ninja, Visual Studio, and XCode. It's designed to be fast, and have a
small, non-Turing complete language to describe the build process,
tests, and dependencies. It's simpler than CMake, and faster than
autotools.

As a direct comparison in terms of speed, three build and check runs for
libepoxy from a clean Git repository clone yield these results on my
Kabylake Core i7 7500U (nproc=4):

- Autotools (make)
Run #1 (cold)   real: 22.384s, user: 20.011s, sys: 3.689s
Run #2 (warm)   real: 22.429s, user: 20.220s, sys: 3.708s
Run #3 (warm)   real: 22.068s, user: 19.743s, sys: 3.594s

- Meson (ninja)
Run #1 (cold)   real: 5.932s, user:  9.371s, sys: 1.625s
Run #2 (warm)   real: 6.273s, user: 10.066,  sys: 1.740s
Run #3 (warm)   real: 5.796s, user:  9.233s, sys: 1.607s

Which means that Meson and ninja are approximately 4x faster than
autotools.

In terms of simplicity, the autotools build takes six files and a total
of 645 lines; Meson requires 3 files, and 361 lines to achieve the same
result. Additionally, Meson automatically builds in a separate build
directory and does not leave files inside the source directory; and Meson
does not use libtool.

Since Meson is quite new and still actively developed, we're going to
leave the autotools build in place for a while, with the intention of
switching to Meson in the future.

1 files changed, 125 insertions, 0 deletions

diff --git a/meson.build b/meson.build
new file mode 100644
index 0000000..101788c
--- /dev/null
+++ b/meson.build
@@ -0,0 +1,125 @@
+project('libepoxy', 'c', version: '1.3.1',
+        default_options: [
+          'buildtype=debug',
+          'c_std=gnu99',
+          'warning_level=1',
+        ],
+        license: 'MIT',
+        meson_version: '>= 0.36.0')
+
+epoxy_version = meson.project_version().split('.')
+epoxy_major_version = epoxy_version[0].to_int()
+epoxy_minor_version = epoxy_version[1].to_int()
+epoxy_micro_version = epoxy_version[2].to_int()
+
+epoxy_prefix = get_option('prefix')
+epoxy_libdir = join_paths(epoxy_prefix, get_option('libdir'))
+epoxy_datadir = join_paths(epoxy_prefix, get_option('datadir'))
+epoxy_includedir = join_paths(epoxy_prefix, get_option('includedir'))
+
+cc = meson.get_compiler('c')
+host_system = host_machine.system()
+
+conf = configuration_data()
+conf.set_quoted('PACKAGE_NAME', meson.project_name())
+conf.set_quoted('PACKAGE_VERSION', meson.project_version())
+conf.set_quoted('PACKAGE_STRING', '@0@-@1@'.format(meson.project_name(), meson.project_version()))
+conf.set_quoted('PACKAGE_DATADIR', join_paths(get_option('prefix'), get_option('datadir')))
+conf.set_quoted('PACKAGE_LIBDIR', join_paths(get_option('prefix'), get_option('libdir')))
+conf.set_quoted('PACKAGE_LOCALEDIR', join_paths(get_option('prefix'), get_option('datadir'), 'locale'))
+conf.set_quoted('PACKAGE_LIBEXECDIR', join_paths(get_option('prefix'), get_option('libexecdir')))
+conf.set('HAVE_KHRPLATFORM_H', cc.has_header('KHR/khrplatform.h', required: false))
+
+if host_system == 'windows'
+  build_glx = false
+  build_egl = false
+  build_apple = false
+  build_wgl = true
+  has_znow = true
+elif host_system == 'darwin'
+  build_glx = false
+  build_egl = false
+  build_apple = true
+  build_wgl = false
+  has_znow = false
+else
+  build_glx = true
+  build_egl = true
+  build_apple = false
+  build_wgl = false
+  has_znow = true
+endif
+
+# Compiler flags, taken from the Xorg macros
+test_cflags = [
+  '-Wall',
+  '-Wpointer-arith',
+  '-Wmissing-declarations',
+  '-Wformat=2',
+  '-Wstrict-prototypes',
+  '-Wmissing-prototypes',
+  '-Wnested-externs',
+  '-Wbad-function-cast',
+  '-Wold-style-definition',
+  '-Wdeclaration-after-statement',
+  '-Wunused',
+  '-Wuninitialized',
+  '-Wshadow',
+  '-Wmissing-noreturn',
+  '-Wmissing-format-attribute',
+  '-Wredundant-decls',
+  '-Wlogical-op',
+  '-Werror=implicit',
+  '-Werror=nonnull',
+  '-Werror=init-self',
+  '-Werror=main',
+  '-Werror=missing-braces',
+  '-Werror=sequence-point',
+  '-Werror=return-type',
+  '-Werror=trigraphs',
+  '-Werror=array-bounds',
+  '-Werror=write-strings',
+  '-Werror=address',
+  '-Werror=int-to-pointer-cast',
+  '-Werror=pointer-to-int-cast',
+  '-fno-strict-aliasing',
+  '-Wno-int-conversion',
+]
+common_cflags = []
+foreach cflag: test_cflags
+  if cc.has_argument(cflag)
+    common_cflags += [ cflag ]
+  endif
+endforeach
+
+# Dependencies
+dl_dep = cc.find_library('dl', required: false)
+gl_dep = dependency('gl', required: false)
+egl_dep = dependency('egl', required: false)
+
+# Optional dependencies for tests
+x11_dep = dependency('x11', required: false)
+gles1_dep = cc.find_library('libGLESv1_CM', required: false)
+gles2_dep = cc.find_library('libGLESv2', required: false)
+
+epoxy_include = include_directories('include')
+
+# PkgConfig file
+pkgconf = configuration_data()
+pkgconf.set('prefix', epoxy_prefix)
+pkgconf.set('exec_prefix', epoxy_prefix)
+pkgconf.set('libdir', epoxy_libdir)
+pkgconf.set('includedir', epoxy_includedir)
+pkgconf.set('PACKAGE_VERSION', meson.project_version())
+if dl_dep.found()
+  pkgconf.set('DLOPEN_LIBS', '-ldl')
+endif
+
+configure_file(input: 'epoxy.pc.in',
+               output: 'epoxy.pc',
+               configuration: pkgconf,
+               install: true,
+               install_dir: join_paths(epoxy_libdir, 'pkgconfig'))
+
+subdir('src')
+subdir('test')