1 files changed, 182 insertions, 0 deletions
diff --git a/project/cmake/toolset.py b/project/cmake/toolset.py
new file mode 100644
index 0000000..0bf8e64
--- /dev/null
+++ b/project/cmake/toolset.py
@@ -0,0 +1,182 @@
+# 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.
+
+# See docs/cmake.md for a more thorough description of my pain.
+
+import abc
+import os.path
+import shutil
+
+import project.mingw
+from project.os import on_windows
+from project.platform import Platform
+from project.toolset import ToolchainType
+
+
+class Toolchain(abc.ABC):
+    @abc.abstractmethod
+    def cmake_args(self):
+        pass
+
+    @abc.abstractmethod
+    def build_system_args(self):
+        pass
+
+    @staticmethod
+    def detect(hint, platform, build_dir):
+        if hint is ToolchainType.AUTO:
+            if on_windows():
+                # On Windows, 'auto' means 'msvc', and we need to specify the
+                # -A parameter.  This might break if none of the Visual Studio
+                # generators are available, but the NMake one is, although I
+                # don't know how this can be possible normally.
+                hint = ToolchainType.MSVC
+            else:
+                # On Linux, if the platform wasn't specified, auto-detect
+                # everything.  There's no need to set -mXX flags, etc.
+                if platform is Platform.AUTO:
+                    return Auto()
+                # If a specific platform was requested, we might need to set
+                # some CMake/compiler flags, like -m32/-m64.
+                hint = ToolchainType.GCC
+        if hint is ToolchainType.MSVC:
+            return MSVC(platform)
+        if hint is ToolchainType.GCC:
+            return GCC.setup(platform, build_dir)
+        if hint is ToolchainType.MINGW:
+            return MinGW.setup(platform, build_dir)
+        if hint is ToolchainType.CLANG:
+            return Clang.setup(platform, build_dir)
+        if hint is ToolchainType.CLANG_CL:
+            return ClangCL.setup(platform, build_dir)
+        raise NotImplementedError(f'unrecognized toolset: {hint}')
+
+
+class Auto(Toolchain):
+    def cmake_args(self):
+        return []
+
+    def build_system_args(self):
+        return []
+
+
+class MSVC(Auto):
+    def __init__(self, platform):
+        self.platform = platform
+
+    def cmake_args(self):
+        # This doesn't actually specify the generator of course, but I don't
+        # want to implement VS detection logic.
+        return ['-A', self.platform.msvc_arch()]
+
+    def build_system_args(self):
+        return []
+
+
+class Makefile(Toolchain):
+    def __init__(self, path):
+        self.path = path
+
+    @staticmethod
+    def _get_config_path(build_dir):
+        return os.path.join(build_dir, 'custom_toolchain.cmake')
+
+    @staticmethod
+    def _get_makefile_generator():
+        if on_windows():
+            if shutil.which('mingw32-make'):
+                return 'MinGW Makefiles'
+            return 'Unix Makefiles'
+        # On Linux/Cygwin, make all the way:
+        return 'Unix Makefiles'
+
+    @classmethod
+    def write_config(cls, build_dir, contents):
+        path = Makefile._get_config_path(build_dir)
+        with open(path, mode='w') as file:
+            file.write(contents)
+        return cls(path)
+
+    def cmake_args(self):
+        return [
+            '-D', f'CMAKE_TOOLCHAIN_FILE={self.path}',
+            # The Visual Studio generator is the default on Windows, override
+            # it:
+            '-G', self._get_makefile_generator(),
+        ]
+
+    def build_system_args(self):
+        return []
+
+
+class GCC(Makefile):
+    @staticmethod
+    def _format(platform):
+        return f'''
+set(CMAKE_C_COMPILER   gcc)
+set(CMAKE_CXX_COMPILER g++)
+{platform.makefile_toolchain_file()}'''
+
+    @staticmethod
+    def setup(platform, build_dir):
+        return GCC.write_config(build_dir, GCC._format(platform))
+
+
+class MinGW(Makefile):
+    @staticmethod
+    def _format(platform):
+        paths = project.mingw.MinGW(platform)
+        return f'''
+set(CMAKE_C_COMPILER   {paths.gcc()})
+set(CMAKE_CXX_COMPILER {paths.gxx()})
+set(CMAKE_AR           {paths.ar()})
+set(CMAKE_RANLIB       {paths.ranlib()})
+set(CMAKE_RC_COMPILER  {paths.windres()})
+set(CMAKE_SYSTEM_NAME  Windows)
+'''
+
+    @staticmethod
+    def setup(platform, build_dir):
+        return MinGW.write_config(build_dir, MinGW._format(platform))
+
+
+class Clang(Makefile):
+    @staticmethod
+    def _format(platform):
+        return f'''
+if(CMAKE_VERSION VERSION_LESS "3.15" AND WIN32)
+    set(CMAKE_C_COMPILER   clang-cl)
+    set(CMAKE_CXX_COMPILER clang-cl)
+else()
+    set(CMAKE_C_COMPILER   clang)
+    set(CMAKE_CXX_COMPILER clang++)
+endif()
+{platform.makefile_toolchain_file()}'''
+
+    def _get_makefile_generator(self):
+        if on_windows():
+            # MinGW utilities like make might be unavailable, but NMake can
+            # very much be there.
+            if shutil.which('nmake'):
+                return 'NMake Makefiles'
+        return super()._get_makefile_generator()
+
+    @staticmethod
+    def setup(platform, build_dir):
+        return Clang.write_config(build_dir, Clang._format(platform))
+
+
+class ClangCL(Clang):
+    @staticmethod
+    def _format(platform):
+        return f'''
+set(CMAKE_C_COMPILER   clang-cl)
+set(CMAKE_CXX_COMPILER clang-cl)
+set(CMAKE_SYSTEM_NAME  Windows)
+{platform.makefile_toolchain_file()}'''
+
+    @staticmethod
+    def setup(platform, build_dir):
+        return ClangCL.write_config(build_dir, ClangCL._format(platform))