build(meson): much more robust build system

build-config/meson.build

@@ -4,6 +4,41 @@ if get_option('build_python')
   subdir('python')
   subdir('pybind')
 endif
+
+if get_option('build_python')
+  gridfire_pkg_dir    = py_installation.get_install_dir() / 'gridfire'
+  gridfire_includedir = gridfire_pkg_dir / 'include'
+  gridfire_libdir     = gridfire_pkg_dir / 'lib'
+  gridfire_pcdir      = gridfire_libdir / 'pkgconfig'
+else
+  gridfire_includedir = get_option('includedir')
+  gridfire_libdir     = get_option('libdir')
+  gridfire_pcdir      = get_option('libdir') / 'pkgconfig'
+endif
+
+gridfire_vendor_includedir = gridfire_includedir / 'gridfire' / 'vendor'
+
+gridfire_fourdst_vendor_includedir = gridfire_includedir / 'fourdst' / 'vendor'
+
+vendor_py = import('python').find_installation('python3')
+copytree_cmd = [
+  vendor_py, '-c',
+  '''import sys, os, stat, shutil
+src, dst = sys.argv[1], sys.argv[2]
+shutil.rmtree(dst, ignore_errors=True)
+shutil.copytree(src, dst)
+for root, dirs, files in os.walk(dst):
+    os.chmod(root, 0o755)
+    for f in files:
+        p = os.path.join(root, f)
+        os.chmod(p, os.stat(p).st_mode | 0o644)
+''',
+]
+copyfiles_cmd = [
+  vendor_py, '-c',
+  'import sys, shutil; [shutil.copy2(p, sys.argv[-1]) for p in sys.argv[1:-1]]',
+]
+
 subdir('fourdst')
 subdir('sundials')
 
@@ -14,7 +49,6 @@ subdir('eigen')
 subdir('json')
 
 subdir('CLI11')
-subdir('unordered_dense')
 
 if get_option('use_mimalloc')
   subdir('mimalloc')