project.boost: first-class MinGW-w64 support

3 files changed, 130 insertions, 15 deletions

diff --git a/project/boost/build.py b/project/boost/build.py
index a33a538..c9081eb 100644
--- a/project/boost/build.py
+++ b/project/boost/build.py
@@ -22,6 +22,7 @@ import sys
 import tempfile
 
 from project.boost.directory import BoostDir
+from project.boost.toolchain import detect_toolchain
 from project.configuration import Configuration
 from project.linkage import Linkage
 from project.platform import Platform
@@ -39,7 +40,7 @@ DEFAULT_B2_ARGS = ['-d0']
 class BuildParameters:
     def __init__(self, boost_dir, build_dir=None, platforms=None,
                  configurations=None, link=None, runtime_link=None,
-                 b2_args=None):
+                 b2_args=None, mingw=False):
 
         boost_dir = project.utils.normalize_path(boost_dir)
         if build_dir is not None:
@@ -61,6 +62,7 @@ class BuildParameters:
         self.link = link
         self.runtime_link = runtime_link
         self.b2_args = b2_args
+        self.mingw = mingw
 
     @staticmethod
     def from_args(args):
@@ -69,11 +71,12 @@ class BuildParameters:
     def enum_b2_args(self):
         with self._create_build_dir() as build_dir:
             for platform in self.platforms:
-                for configuration in self.configurations:
-                    for link, runtime_link in self._linkage_options():
-                        yield self._build_params(build_dir, platform,
-                                                 configuration, link,
-                                                 runtime_link)
+                with detect_toolchain(platform, mingw=self.mingw) as toolchain:
+                    for configuration in self.configurations:
+                        for link, runtime_link in self._linkage_options():
+                            yield self._build_params(build_dir, toolchain,
+                                                     configuration, link,
+                                                     runtime_link)
 
     def _linkage_options(self):
         for link in self.link:
@@ -102,13 +105,13 @@ class BuildParameters:
                 logging.info('Removing build directory: %s', build_dir)
             return
 
-    def _build_params(self, build_dir, platform, configuration, link, runtime_link):
+    def _build_params(self, build_dir, toolchain, configuration, link, runtime_link):
         params = []
         params.append(self._build_dir(build_dir))
-        params.append(self._stagedir(platform, configuration))
+        params.append(self._stagedir(toolchain, configuration))
+        params += toolchain.get_b2_args()
         params.append(self._link(link))
         params.append(self._runtime_link(runtime_link))
-        params.append(self._address_model(platform))
         params.append(self._variant(configuration))
         params += self.b2_args
         return params
@@ -117,7 +120,7 @@ class BuildParameters:
     def _build_dir(build_dir):
         return f'--build-dir={build_dir}'
 
-    def _stagedir(self, platform, configuration):
+    def _stagedir(self, toolchain, configuration):
         # Having different --stagedir values for every configuration/platform
         # combination is unnecessary on Windows.  Even for older Boost versions
         # (when the binaries weren't tagged with their target platform) only a
@@ -125,7 +128,7 @@ class BuildParameters:
         # versions, just a single --stagedir would do, as the binaries are
         # tagged with the target platform, as well as their configuration
         # (a.k.a. "variant" in Boost's terminology).  Still, uniformity helps.
-        platform = str(platform)
+        platform = str(toolchain.platform)
         configuration = str(configuration)
         return f'--stagedir={os.path.join(self.stage_dir, platform, configuration)}'
 
@@ -138,10 +141,6 @@ class BuildParameters:
         return f'runtime-link={runtime_link}'
 
     @staticmethod
-    def _address_model(platform):
-        return f'address-model={platform.get_address_model()}'
-
-    @staticmethod
     def _variant(configuration):
         return f'variant={configuration.to_boost_variant()}'
 
@@ -195,6 +194,9 @@ def _parse_args(argv=None):
                         nargs='*', default=[],
                         help='additional b2 arguments, to be passed verbatim')
 
+    parser.add_argument('--mingw', action='store_true',
+                        help='build using MinGW-w64')
+
     return parser.parse_args(argv)
 
 
diff --git a/project/boost/toolchain.py b/project/boost/toolchain.py
new file mode 100644
index 0000000..9cc452b
--- /dev/null
+++ b/project/boost/toolchain.py
@@ -0,0 +1,108 @@
+# Copyright (c) 2020 Egor Tensin <Egor.Tensin@gmail.com>
+# This file is part of the "cmake-common" project.
+# For details, see https://github.com/egor-tensin/cmake-common.
+# Distributed under the MIT License.
+
+R'''Compiler detection.
+
+It is assumed that Boost.Build is good enough to detect both GCC on Linux and
+MSVC on Windows.  From that point on, it's just a matter of setting the correct
+address-model= value.
+
+But I also frequently use MinGW-w64, and the most convinient way to use it that
+I know is making a "user config" and passing it to b2 using the --user-config
+parameter.
+'''
+
+import abc
+from contextlib import contextmanager
+import logging
+import tempfile
+
+import project.os
+
+
+class Toolchain(abc.ABC):
+    def __init__(self, platform):
+        self.platform = platform
+
+    @abc.abstractmethod
+    def get_b2_args(self):
+        pass
+
+
+class NativeToolchain(Toolchain):
+    def get_b2_args(self):
+        return [f'address-model={self.platform.get_address_model()}']
+
+
+class MingwToolchain(Toolchain):
+    TAG = 'custom'
+
+    def __init__(self, platform, config_path):
+        super().__init__(platform)
+        self.config_path = config_path
+
+    def get_b2_args(self):
+        return [f'--user-config={self.config_path}', f'toolset=gcc-{MingwToolchain.TAG}']
+
+
+def _native_toolchain(platform):
+    return NativeToolchain(platform)
+
+
+def _get_mingw_prefix(platform):
+    target_arch = platform.get_address_model()
+    if target_arch == 32:
+        return 'i686'
+    if target_arch == 64:
+        return 'x86_64'
+    raise RuntimeError(f'unexpected address model: {target_arch}')
+
+
+def _get_mingw_path(platform):
+    prefix = _get_mingw_prefix(platform)
+    ext = ''
+    if project.os.on_windows_like():
+        # Boost.Build wants the .exe extension at the end on Cygwin.
+        ext = '.exe'
+    path = f'{prefix}-w64-mingw32-g++{ext}'
+    return path
+
+
+def _format_user_config(tag, compiler, **kwargs):
+    features = (f'<{k}>{v}' for k, v in kwargs.items())
+    features = ' '.join(features)
+    return f'using gcc : {tag} : {compiler} : {features} ;'
+
+
+def _format_mingw_user_config(platform):
+    compiler = _get_mingw_path(platform)
+    features = {
+        'target-os': 'windows',
+        'address-model': platform.get_address_model(),
+    }
+    return _format_user_config(MingwToolchain.TAG, compiler, **features)
+
+
+@contextmanager
+def _mingw_toolchain(platform):
+    tmp = tempfile.NamedTemporaryFile(mode='w', prefix='mingw_w64_', suffix='.jam')
+    with tmp as file:
+        config = _format_mingw_user_config(platform)
+        logging.info('Using user config:\n%s', config)
+        file.write(config)
+        file.flush()
+        try:
+            yield MingwToolchain(platform, file.name)
+        finally:
+            logging.info('Removing temporary user config file')
+
+
+@contextmanager
+def detect_toolchain(platform, mingw=False):
+    if mingw:
+        with _mingw_toolchain(platform) as toolchain:
+            yield toolchain
+    else:
+        yield _native_toolchain(platform)
diff --git a/project/os.py b/project/os.py
index 86ccaad..2f5f088 100644
--- a/project/os.py
+++ b/project/os.py
@@ -31,6 +31,11 @@ def on_windows():
     return OS.current() is OS.WINDOWS
 
 
+def on_windows_like():
+    os = OS.current()
+    return os is OS.WINDOWS or os is OS.CYGWIN
+
+
 def on_linux_like():
     os = OS.current()
     return os is OS.LINUX or os is OS.CYGWIN