remove obsolete Boost dependency

Boost makes building a piece of software much more difficult than
necessary.  It's a huge library, and just uncompressing it takes a
considerable amount of time. MPD only used a tiny fraction of it, yet
its header bloat made the MPD build very slow.  Locating Boost was
difficult due to its arcane build system and its resistance to use
pkg-config; it's always a special case.  MPD could never use features
of newer Boost versions because Linux distributions always shipped old
Boost versions.  Boost made everything complicated and slow.

So, finally, after getting rid of GLib (commit ccdb94b06c), switching
to C++ and using Boost (commit 0801b3f495), we've finally get rid of
it 8 years later.

Unfortunately, I had to reimplement parts of it along the way
(e.g. IntrusiveList).  Kind of NIH, but on the other hand, compiling
MPD has become much easier for users.

python/build/boost.py

@@ -1,28 +0,0 @@
-import os, shutil
-import re
-
-from build.project import Project
-
-class BoostProject(Project):
-    def __init__(self, url, md5, installed,
-                 **kwargs):
-        m = re.match(r'.*/boost_(\d+)_(\d+)_(\d+)\.tar\.bz2$', url)
-        version = "%s.%s.%s" % (m.group(1), m.group(2), m.group(3))
-        Project.__init__(self, url, md5, installed,
-                         name='boost', version=version,
-                         **kwargs)
-
-    def _build(self, toolchain):
-        src = self.unpack(toolchain)
-
-        # install the headers manually; don't build any library
-        # (because right now, we only use header-only libraries)
-        includedir = os.path.join(toolchain.install_prefix, 'include')
-        dest = os.path.join(includedir, 'boost')
-        shutil.rmtree(dest, ignore_errors=True)
-        shutil.copytree(os.path.join(src, 'boost'), dest)
-
-        # touch the boost/version.hpp file to ensure it's newer than
-        # the downloaded Boost tarball, to avoid reinstalling Boost on
-        # every run
-        os.utime(os.path.join(toolchain.install_prefix, self.installed))

python/build/libs.py

@@ -8,7 +8,6 @@ from build.cmake import CmakeProject
 from build.autotools import AutotoolsProject
 from build.ffmpeg import FfmpegProject
 from build.openssl import OpenSSLProject
-from build.boost import BoostProject
 from build.jack import JackProject
 
 libmpdclient = MesonProject(
@@ -448,9 +447,3 @@ jack = JackProject(
     '38f674bbc57852a8eb3d9faa1f96a0912d26f7d5df14c11005ad499c8ae352f2',
     'lib/pkgconfig/jack.pc',
 )
-
-boost = BoostProject(
-    'https://boostorg.jfrog.io/artifactory/main/release/1.81.0/source/boost_1_81_0.tar.bz2',
-    '71feeed900fbccca04a3b4f2f84a7c217186f28a940ed8b7ed4725986baf99fa',
-    'include/boost/version.hpp',
-)

python/build/meson.py

@@ -96,9 +96,6 @@ def configure(toolchain, src, build, args=()):
 
     env = toolchain.env.copy()
 
-    # Meson 0.54 requires the BOOST_ROOT environment variable
-    env['BOOST_ROOT'] = toolchain.install_prefix
-
     subprocess.check_call(configure, env=env)
 
 class MesonProject(Project):