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meson/mesonbuild/dependencies/cmake.py

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# Copyright 2013-2021 The Meson development team
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
# http://www.apache.org/licenses/LICENSE-2.0
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from __future__ import annotations
from .base import ExternalDependency, DependencyException, DependencyTypeName
from ..mesonlib import is_windows, MesonException, PerMachine, stringlistify, extract_as_list
from ..cmake import CMakeExecutor, CMakeTraceParser, CMakeException, CMakeToolchain, CMakeExecScope, check_cmake_args, resolve_cmake_trace_targets, cmake_is_debug
from .. import mlog
import importlib.resources
from pathlib import Path
import functools
import re
import os
import shutil
import textwrap
import typing as T
if T.TYPE_CHECKING:
from ..cmake import CMakeTarget
from ..environment import Environment
from ..envconfig import MachineInfo
class CMakeInfo(T.NamedTuple):
module_paths: T.List[str]
cmake_root: str
archs: T.List[str]
common_paths: T.List[str]
class CMakeDependency(ExternalDependency):
# The class's copy of the CMake path. Avoids having to search for it
# multiple times in the same Meson invocation.
class_cmakeinfo: PerMachine[T.Optional[CMakeInfo]] = PerMachine(None, None)
# Version string for the minimum CMake version
class_cmake_version = '>=3.4'
# CMake generators to try (empty for no generator)
class_cmake_generators = ['', 'Ninja', 'Unix Makefiles', 'Visual Studio 10 2010']
class_working_generator: T.Optional[str] = None
def _gen_exception(self, msg: str) -> DependencyException:
return DependencyException(f'Dependency {self.name} not found: {msg}')
def _main_cmake_file(self) -> str:
return 'CMakeLists.txt'
def _extra_cmake_opts(self) -> T.List[str]:
return []
def _map_module_list(self, modules: T.List[T.Tuple[str, bool]], components: T.List[T.Tuple[str, bool]]) -> T.List[T.Tuple[str, bool]]:
# Map the input module list to something else
# This function will only be executed AFTER the initial CMake
# interpreter pass has completed. Thus variables defined in the
# CMakeLists.txt can be accessed here.
#
# Both the modules and components inputs contain the original lists.
return modules
def _map_component_list(self, modules: T.List[T.Tuple[str, bool]], components: T.List[T.Tuple[str, bool]]) -> T.List[T.Tuple[str, bool]]:
# Map the input components list to something else. This
# function will be executed BEFORE the initial CMake interpreter
# pass. Thus variables from the CMakeLists.txt can NOT be accessed.
#
# Both the modules and components inputs contain the original lists.
return components
def _original_module_name(self, module: str) -> str:
# Reverse the module mapping done by _map_module_list for
# one module
return module
def __init__(self, name: str, environment: 'Environment', kwargs: T.Dict[str, T.Any], language: T.Optional[str] = None, force_use_global_compilers: bool = False) -> None:
# Gather a list of all languages to support
self.language_list = [] # type: T.List[str]
if language is None or force_use_global_compilers:
compilers = None
if kwargs.get('native', False):
compilers = environment.coredata.compilers.build
else:
compilers = environment.coredata.compilers.host
candidates = ['c', 'cpp', 'fortran', 'objc', 'objcxx']
self.language_list += [x for x in candidates if x in compilers]
else:
self.language_list += [language]
# Add additional languages if required
if 'fortran' in self.language_list:
self.language_list += ['c']
# Ensure that the list is unique
self.language_list = list(set(self.language_list))
super().__init__(DependencyTypeName('cmake'), environment, kwargs, language=language)
self.name = name
self.is_libtool = False
# Store a copy of the CMake path on the object itself so it is
# stored in the pickled coredata and recovered.
self.cmakebin: T.Optional[CMakeExecutor] = None
self.cmakeinfo: T.Optional[CMakeInfo] = None
# Where all CMake "build dirs" are located
self.cmake_root_dir = environment.scratch_dir
# T.List of successfully found modules
self.found_modules: T.List[str] = []
# Initialize with None before the first return to avoid
# AttributeError exceptions in derived classes
self.traceparser: T.Optional[CMakeTraceParser] = None
# TODO further evaluate always using MachineChoice.BUILD
self.cmakebin = CMakeExecutor(environment, CMakeDependency.class_cmake_version, self.for_machine, silent=self.silent)
if not self.cmakebin.found():
self.cmakebin = None
msg = f'CMake binary for machine {self.for_machine} not found. Giving up.'
if self.required:
raise DependencyException(msg)
mlog.debug(msg)
return
# Setup the trace parser
self.traceparser = CMakeTraceParser(self.cmakebin.version(), self._get_build_dir(), self.env)
cm_args = stringlistify(extract_as_list(kwargs, 'cmake_args'))
cm_args = check_cmake_args(cm_args)
if CMakeDependency.class_cmakeinfo[self.for_machine] is None:
CMakeDependency.class_cmakeinfo[self.for_machine] = self._get_cmake_info(cm_args)
self.cmakeinfo = CMakeDependency.class_cmakeinfo[self.for_machine]
if self.cmakeinfo is None:
raise self._gen_exception('Unable to obtain CMake system information')
package_version = kwargs.get('cmake_package_version', '')
if not isinstance(package_version, str):
raise DependencyException('Keyword "cmake_package_version" must be a string.')
components = [(x, True) for x in stringlistify(extract_as_list(kwargs, 'components'))]
modules = [(x, True) for x in stringlistify(extract_as_list(kwargs, 'modules'))]
modules += [(x, False) for x in stringlistify(extract_as_list(kwargs, 'optional_modules'))]
cm_path = stringlistify(extract_as_list(kwargs, 'cmake_module_path'))
cm_path = [x if os.path.isabs(x) else os.path.join(environment.get_source_dir(), x) for x in cm_path]
if cm_path:
cm_args.append('-DCMAKE_MODULE_PATH=' + ';'.join(cm_path))
if not self._preliminary_find_check(name, cm_path, self.cmakebin.get_cmake_prefix_paths(), environment.machines[self.for_machine]):
mlog.debug('Preliminary CMake check failed. Aborting.')
return
self._detect_dep(name, package_version, modules, components, cm_args)
def __repr__(self) -> str:
return f'<{self.__class__.__name__} {self.name}: {self.is_found} {self.version_reqs}>'
def _get_cmake_info(self, cm_args: T.List[str]) -> T.Optional[CMakeInfo]:
mlog.debug("Extracting basic cmake information")
# Try different CMake generators since specifying no generator may fail
# in cygwin for some reason
gen_list = []
# First try the last working generator
if CMakeDependency.class_working_generator is not None:
gen_list += [CMakeDependency.class_working_generator]
gen_list += CMakeDependency.class_cmake_generators
temp_parser = CMakeTraceParser(self.cmakebin.version(), self._get_build_dir(), self.env)
toolchain = CMakeToolchain(self.cmakebin, self.env, self.for_machine, CMakeExecScope.DEPENDENCY, self._get_build_dir())
toolchain.write()
for i in gen_list:
mlog.debug('Try CMake generator: {}'.format(i if len(i) > 0 else 'auto'))
# Prepare options
cmake_opts = temp_parser.trace_args() + toolchain.get_cmake_args() + ['.']
cmake_opts += cm_args
if len(i) > 0:
cmake_opts = ['-G', i] + cmake_opts
# Run CMake
ret1, out1, err1 = self._call_cmake(cmake_opts, 'CMakePathInfo.txt')
# Current generator was successful
if ret1 == 0:
CMakeDependency.class_working_generator = i
break
mlog.debug(f'CMake failed to gather system information for generator {i} with error code {ret1}')
mlog.debug(f'OUT:\n{out1}\n\n\nERR:\n{err1}\n\n')
# Check if any generator succeeded
if ret1 != 0:
return None
try:
temp_parser.parse(err1)
except MesonException:
return None
def process_paths(l: T.List[str]) -> T.Set[str]:
if is_windows():
# Cannot split on ':' on Windows because its in the drive letter
tmp = [x.split(os.pathsep) for x in l]
else:
# https://github.com/mesonbuild/meson/issues/7294
tmp = [re.split(r':|;', x) for x in l]
flattened = [x for sublist in tmp for x in sublist]
return set(flattened)
# Extract the variables and sanity check them
root_paths_set = process_paths(temp_parser.get_cmake_var('MESON_FIND_ROOT_PATH'))
root_paths_set.update(process_paths(temp_parser.get_cmake_var('MESON_CMAKE_SYSROOT')))
root_paths = sorted(root_paths_set)
root_paths = [x for x in root_paths if os.path.isdir(x)]
module_paths_set = process_paths(temp_parser.get_cmake_var('MESON_PATHS_LIST'))
rooted_paths: T.List[str] = []
for j in [Path(x) for x in root_paths]:
for p in [Path(x) for x in module_paths_set]:
rooted_paths.append(str(j / p.relative_to(p.anchor)))
module_paths = sorted(module_paths_set.union(rooted_paths))
module_paths = [x for x in module_paths if os.path.isdir(x)]
archs = temp_parser.get_cmake_var('MESON_ARCH_LIST')
common_paths = ['lib', 'lib32', 'lib64', 'libx32', 'share']
for i in archs:
common_paths += [os.path.join('lib', i)]
res = CMakeInfo(
module_paths=module_paths,
cmake_root=temp_parser.get_cmake_var('MESON_CMAKE_ROOT')[0],
archs=archs,
common_paths=common_paths,
)
mlog.debug(f' -- Module search paths: {res.module_paths}')
mlog.debug(f' -- CMake root: {res.cmake_root}')
mlog.debug(f' -- CMake architectures: {res.archs}')
mlog.debug(f' -- CMake lib search paths: {res.common_paths}')
return res
@staticmethod
@functools.lru_cache(maxsize=None)
def _cached_listdir(path: str) -> T.Tuple[T.Tuple[str, str], ...]:
try:
return tuple((x, str(x).lower()) for x in os.listdir(path))
except OSError:
return tuple()
@staticmethod
@functools.lru_cache(maxsize=None)
def _cached_isdir(path: str) -> bool:
try:
return os.path.isdir(path)
except OSError:
return False
def _preliminary_find_check(self, name: str, module_path: T.List[str], prefix_path: T.List[str], machine: 'MachineInfo') -> bool:
lname = str(name).lower()
# Checks <path>, <path>/cmake, <path>/CMake
def find_module(path: str) -> bool:
for i in [path, os.path.join(path, 'cmake'), os.path.join(path, 'CMake')]:
if not self._cached_isdir(i):
continue
# Check the directory case insensitive
content = self._cached_listdir(i)
candidates = ['Find{}.cmake', '{}Config.cmake', '{}-config.cmake']
candidates = [x.format(name).lower() for x in candidates]
if any(x[1] in candidates for x in content):
return True
return False
# Search in <path>/(lib/<arch>|lib*|share) for cmake files
def search_lib_dirs(path: str) -> bool:
for i in [os.path.join(path, x) for x in self.cmakeinfo.common_paths]:
if not self._cached_isdir(i):
continue
# Check <path>/(lib/<arch>|lib*|share)/cmake/<name>*/
cm_dir = os.path.join(i, 'cmake')
if self._cached_isdir(cm_dir):
content = self._cached_listdir(cm_dir)
content = tuple(x for x in content if x[1].startswith(lname))
for k in content:
if find_module(os.path.join(cm_dir, k[0])):
return True
# <path>/(lib/<arch>|lib*|share)/<name>*/
# <path>/(lib/<arch>|lib*|share)/<name>*/(cmake|CMake)/
content = self._cached_listdir(i)
content = tuple(x for x in content if x[1].startswith(lname))
for k in content:
if find_module(os.path.join(i, k[0])):
return True
return False
# Check the user provided and system module paths
for i in module_path + [os.path.join(self.cmakeinfo.cmake_root, 'Modules')]:
if find_module(i):
return True
# Check the user provided prefix paths
for i in prefix_path:
if search_lib_dirs(i):
return True
# Check PATH
system_env = [] # type: T.List[str]
for i in os.environ.get('PATH', '').split(os.pathsep):
if i.endswith('/bin') or i.endswith('\\bin'):
i = i[:-4]
if i.endswith('/sbin') or i.endswith('\\sbin'):
i = i[:-5]
system_env += [i]
# Check the system paths
for i in self.cmakeinfo.module_paths + system_env:
if find_module(i):
return True
if search_lib_dirs(i):
return True
content = self._cached_listdir(i)
content = tuple(x for x in content if x[1].startswith(lname))
for k in content:
if search_lib_dirs(os.path.join(i, k[0])):
return True
# Mac framework support
if machine.is_darwin():
for j in [f'{lname}.framework', f'{lname}.app']:
for k in content:
if k[1] != j:
continue
if find_module(os.path.join(i, k[0], 'Resources')) or find_module(os.path.join(i, k[0], 'Version')):
return True
# Check the environment path
env_path = os.environ.get(f'{name}_DIR')
if env_path and find_module(env_path):
return True
# Check the Linux CMake registry
linux_reg = Path.home() / '.cmake' / 'packages'
for p in [linux_reg / name, linux_reg / lname]:
if p.exists():
return True
return False
def _detect_dep(self, name: str, package_version: str, modules: T.List[T.Tuple[str, bool]], components: T.List[T.Tuple[str, bool]], args: T.List[str]) -> None:
# Detect a dependency with CMake using the '--find-package' mode
# and the trace output (stderr)
#
# When the trace output is enabled CMake prints all functions with
# parameters to stderr as they are executed. Since CMake 3.4.0
# variables ("${VAR}") are also replaced in the trace output.
mlog.debug('\nDetermining dependency {!r} with CMake executable '
'{!r}'.format(name, self.cmakebin.executable_path()))
# Try different CMake generators since specifying no generator may fail
# in cygwin for some reason
gen_list = []
# First try the last working generator
if CMakeDependency.class_working_generator is not None:
gen_list += [CMakeDependency.class_working_generator]
gen_list += CMakeDependency.class_cmake_generators
# Map the components
comp_mapped = self._map_component_list(modules, components)
toolchain = CMakeToolchain(self.cmakebin, self.env, self.for_machine, CMakeExecScope.DEPENDENCY, self._get_build_dir())
toolchain.write()
for i in gen_list:
mlog.debug('Try CMake generator: {}'.format(i if len(i) > 0 else 'auto'))
# Prepare options
cmake_opts = []
cmake_opts += [f'-DNAME={name}']
cmake_opts += ['-DARCHS={}'.format(';'.join(self.cmakeinfo.archs))]
cmake_opts += [f'-DVERSION={package_version}']
cmake_opts += ['-DCOMPS={}'.format(';'.join([x[0] for x in comp_mapped]))]
cmake_opts += [f'-DSTATIC={self.static}']
cmake_opts += args
cmake_opts += self.traceparser.trace_args()
cmake_opts += toolchain.get_cmake_args()
cmake_opts += self._extra_cmake_opts()
cmake_opts += ['.']
if len(i) > 0:
cmake_opts = ['-G', i] + cmake_opts
# Run CMake
ret1, out1, err1 = self._call_cmake(cmake_opts, self._main_cmake_file())
# Current generator was successful
if ret1 == 0:
CMakeDependency.class_working_generator = i
break
mlog.debug(f'CMake failed for generator {i} and package {name} with error code {ret1}')
mlog.debug(f'OUT:\n{out1}\n\n\nERR:\n{err1}\n\n')
# Check if any generator succeeded
if ret1 != 0:
return
try:
self.traceparser.parse(err1)
except CMakeException as e:
e2 = self._gen_exception(str(e))
if self.required:
raise
else:
self.compile_args = []
self.link_args = []
self.is_found = False
self.reason = e2
return
# Whether the package is found or not is always stored in PACKAGE_FOUND
self.is_found = self.traceparser.var_to_bool('PACKAGE_FOUND')
if not self.is_found:
return
# Try to detect the version
vers_raw = self.traceparser.get_cmake_var('PACKAGE_VERSION')
if len(vers_raw) > 0:
self.version = vers_raw[0]
self.version.strip('"\' ')
# Post-process module list. Used in derived classes to modify the
# module list (append prepend a string, etc.).
modules = self._map_module_list(modules, components)
autodetected_module_list = False
# Try guessing a CMake target if none is provided
if len(modules) == 0:
for i in self.traceparser.targets:
tg = i.lower()
lname = name.lower()
if f'{lname}::{lname}' == tg or lname == tg.replace('::', ''):
mlog.debug(f'Guessed CMake target \'{i}\'')
modules = [(i, True)]
autodetected_module_list = True
break
# Failed to guess a target --> try the old-style method
if len(modules) == 0:
# Warn when there might be matching imported targets but no automatic match was used
partial_modules: T.List[CMakeTarget] = []
for k, v in self.traceparser.targets.items():
tg = k.lower()
lname = name.lower()
if tg.startswith(f'{lname}::'):
partial_modules += [v]
if partial_modules:
mlog.warning(textwrap.dedent(f'''\
Could not find and exact match for the CMake dependency {name}.
However, Meson found the following partial matches:
{[x.name for x in partial_modules]}
Using imported is recommended, since this approach is less error prone
and better supported by Meson. Consider explicitly specifying one of
these in the dependency call with:
dependency('{name}', modules: ['{name}::<name>', ...])
Meson will now continue to use the old-style {name}_LIBRARIES CMake
variables to extract the dependency information since no explicit
target is currently specified.
'''))
mlog.debug('More info for the partial match targets:')
for tgt in partial_modules:
mlog.debug(tgt)
incDirs = [x for x in self.traceparser.get_cmake_var('PACKAGE_INCLUDE_DIRS') if x]
defs = [x for x in self.traceparser.get_cmake_var('PACKAGE_DEFINITIONS') if x]
libs_raw = [x for x in self.traceparser.get_cmake_var('PACKAGE_LIBRARIES') if x]
# CMake has a "fun" API, where certain keywords describing
# configurations can be in the *_LIBRARIES variables. See:
# - https://github.com/mesonbuild/meson/issues/9197
# - https://gitlab.freedesktop.org/libnice/libnice/-/issues/140
# - https://cmake.org/cmake/help/latest/command/target_link_libraries.html#overview (the last point in the section)
libs: T.List[str] = []
cfg_matches = True
is_debug = cmake_is_debug(self.env)
cm_tag_map = {'debug': is_debug, 'optimized': not is_debug, 'general': True}
for i in libs_raw:
if i.lower() in cm_tag_map:
cfg_matches = cm_tag_map[i.lower()]
continue
if cfg_matches:
libs += [i]
# According to the CMake docs, a keyword only works for the
# directly the following item and all items without a keyword
# are implicitly `general`
cfg_matches = True
# Try to use old style variables if no module is specified
if len(libs) > 0:
self.compile_args = [f'-I{x}' for x in incDirs] + defs
self.link_args = []
for j in libs:
rtgt = resolve_cmake_trace_targets(j, self.traceparser, self.env, clib_compiler=self.clib_compiler)
self.link_args += rtgt.libraries
self.compile_args += [f'-I{x}' for x in rtgt.include_directories]
self.compile_args += rtgt.public_compile_opts
mlog.debug(f'using old-style CMake variables for dependency {name}')
mlog.debug(f'Include Dirs: {incDirs}')
mlog.debug(f'Compiler Definitions: {defs}')
mlog.debug(f'Libraries: {libs}')
return
# Even the old-style approach failed. Nothing else we can do here
self.is_found = False
raise self._gen_exception('CMake: failed to guess a CMake target for {}.\n'
'Try to explicitly specify one or more targets with the "modules" property.\n'
'Valid targets are:\n{}'.format(name, list(self.traceparser.targets.keys())))
# Set dependencies with CMake targets
# recognise arguments we should pass directly to the linker
incDirs = []
compileOptions = []
libraries = []
for i, required in modules:
if i not in self.traceparser.targets:
if not required:
mlog.warning('CMake: T.Optional module', mlog.bold(self._original_module_name(i)), 'for', mlog.bold(name), 'was not found')
continue
raise self._gen_exception('CMake: invalid module {} for {}.\n'
'Try to explicitly specify one or more targets with the "modules" property.\n'
'Valid targets are:\n{}'.format(self._original_module_name(i), name, list(self.traceparser.targets.keys())))
if not autodetected_module_list:
self.found_modules += [i]
rtgt = resolve_cmake_trace_targets(i, self.traceparser, self.env,
clib_compiler=self.clib_compiler,
not_found_warning=lambda x:
mlog.warning('CMake: Dependency', mlog.bold(x), 'for', mlog.bold(name), 'was not found')
)
incDirs += rtgt.include_directories
compileOptions += rtgt.public_compile_opts
libraries += rtgt.libraries + rtgt.link_flags
# Make sure all elements in the lists are unique and sorted
incDirs = sorted(set(incDirs))
compileOptions = sorted(set(compileOptions))
libraries = sorted(set(libraries))
mlog.debug(f'Include Dirs: {incDirs}')
mlog.debug(f'Compiler Options: {compileOptions}')
mlog.debug(f'Libraries: {libraries}')
self.compile_args = compileOptions + [f'-I{x}' for x in incDirs]
self.link_args = libraries
def _get_build_dir(self) -> Path:
build_dir = Path(self.cmake_root_dir) / f'cmake_{self.name}'
build_dir.mkdir(parents=True, exist_ok=True)
return build_dir
def _setup_cmake_dir(self, cmake_file: str) -> Path:
# Setup the CMake build environment and return the "build" directory
build_dir = self._get_build_dir()
# Remove old CMake cache so we can try out multiple generators
cmake_cache = build_dir / 'CMakeCache.txt'
cmake_files = build_dir / 'CMakeFiles'
if cmake_cache.exists():
cmake_cache.unlink()
shutil.rmtree(cmake_files.as_posix(), ignore_errors=True)
# Insert language parameters into the CMakeLists.txt and write new CMakeLists.txt
cmake_txt = importlib.resources.read_text('mesonbuild.dependencies.data', cmake_file, encoding = 'utf-8')
# In general, some Fortran CMake find_package() also require C language enabled,
# even if nothing from C is directly used. An easy Fortran example that fails
# without C language is
# find_package(Threads)
# To make this general to
# any other language that might need this, we use a list for all
# languages and expand in the cmake Project(... LANGUAGES ...) statement.
from ..cmake import language_map
cmake_language = [language_map[x] for x in self.language_list if x in language_map]
if not cmake_language:
cmake_language += ['NONE']
cmake_txt = textwrap.dedent("""
cmake_minimum_required(VERSION ${{CMAKE_VERSION}})
project(MesonTemp LANGUAGES {})
""").format(' '.join(cmake_language)) + cmake_txt
cm_file = build_dir / 'CMakeLists.txt'
cm_file.write_text(cmake_txt, encoding='utf-8')
mlog.cmd_ci_include(cm_file.absolute().as_posix())
return build_dir
def _call_cmake(self,
args: T.List[str],
cmake_file: str,
env: T.Optional[T.Dict[str, str]] = None) -> T.Tuple[int, T.Optional[str], T.Optional[str]]:
build_dir = self._setup_cmake_dir(cmake_file)
return self.cmakebin.call(args, build_dir, env=env)
@staticmethod
def log_tried() -> str:
return 'cmake'
def log_details(self) -> str:
modules = [self._original_module_name(x) for x in self.found_modules]
modules = sorted(set(modules))
if modules:
return 'modules: ' + ', '.join(modules)
return ''
def get_variable(self, *, cmake: T.Optional[str] = None, pkgconfig: T.Optional[str] = None,
configtool: T.Optional[str] = None, internal: T.Optional[str] = None,
default_value: T.Optional[str] = None,
pkgconfig_define: T.Optional[T.List[str]] = None) -> str:
if cmake and self.traceparser is not None:
try:
v = self.traceparser.vars[cmake]
except KeyError:
pass
else:
# CMake does NOT have a list datatype. We have no idea whether
# anything is a string or a string-separated-by-; Internally,
# we treat them as the latter and represent everything as a
# list, because it is convenient when we are mostly handling
# imported targets, which have various properties that are
# actually lists.
#
# As a result we need to convert them back to strings when grabbing
# raw variables the user requested.
return ';'.join(v)
if default_value is not None:
return default_value
raise DependencyException(f'Could not get cmake variable and no default provided for {self!r}')