Pango 1.52.1

Bazel-native Linux build of upstream Pango 1.52.1, licensed LGPL-2.1-or-later. The release's COPYING file and copyright notices are retained.

Targets

Add bazel_dep(name = "pango", version = "1.52.1") to MODULE.bazel.

The HarfBuzz/ICU dependencies require C++17 or newer. With a toolchain that defaults to an older standard (including Bazel 7‘s default Linux toolchain), add this to your project’s .bazelrc:

build --cxxopt=-std=c++17

C/C++ consumers can link the cc_library targets statically or use the explicit shared targets through cc_shared_library.dynamic_deps. The explicit shared libraries own dependency implementations once: core Pango contains the common text stack; FT2 depends dynamically on core; PangoCairo depends on both and contains Cairo/Pixman. FFI consumers using GLib/GObject or fontconfig APIs should resolve those functions from pango_shared to keep objects in the same native stack. Standard C/C++ runtime libraries come from the execution platform.

Loading from runfiles

For a Python binary, pass a runfiles path and declare the shared target as data:

args = ["$(rlocationpath @pango//:pangocairo_shared)"],
data = ["@pango//:pangocairo_shared"],
deps = ["@rules_python//python/runfiles"],

import ctypes
import os
import sys
from python.runfiles import runfiles

library_path = runfiles.Create().Rlocation(sys.argv[1])
library = ctypes.CDLL(library_path, mode=os.RTLD_NOW | os.RTLD_LOCAL)

The same resolved path works with ffi.dlopen. Bazel supplies transitive shared library runfiles. Use rlocationpath rather than hard-coding repository names. When materializing runfiles, preserve file identity (for example, cp -aL), or copy the three .so.0 files together into one directory. SONAMEs and $ORIGIN search paths support that layout. Avoid loading separate copies through both a canonical path and a _solib alias. No host Pango or LD_LIBRARY_PATH is needed.

Fonts and Thai dictionaries

Consumers supply font files and fontconfig configuration as runtime inputs. For hermetic rendering, package them in runfiles and initialize an explicit fontconfig configuration. The test module demonstrates FcConfigAppFontAddFile and pango_fc_font_map_set_config with bundled fonts and no host font discovery.

Thai word breaking uses libthai's embedded dictionary by default, including after relocation. To override it, add @libthai//:dictionary to data, resolve its runfiles path, and set LIBTHAI_DICTDIR to the parent directory before the first layout call. This requires a direct libthai dependency. An unusable override falls back to the embedded dictionary.

This initial port supports Linux with the FreeType/fontconfig and Cairo backends. Xft, native macOS/Windows backends, and introspection are not included.