SystemPackageConan

conanfile.py

from conans import ConanFile, tools
from configparser import ConfigParser
import os

def remove_prefix(s, prefix):
    return s[len(prefix):] if s.startswith(prefix) else s

class SystemPackageConan(ConanFile):
    settings = 'os', 'arch'
    options = { "pkg_config" : "ANY" }

    def config_options(self):
        if not self.develop: # pkg_config option is only for `conan create`
            del self.options.pkg_config

    def build(self):
        build_options = ConfigParser()
        if self.options.pkg_config:
            build_options['pkg_config'] = {}
            build_options['pkg_config']['module'] = str(self.options.pkg_config)
            if self.env.get('PKG_CONFIG_SYSROOT_DIR'):
                build_options['pkg_config']['sysroot'] = self.env.get('PKG_CONFIG_SYSROOT_DIR')

        with open('build_options.txt','w') as options_file:
            build_options.write(options_file)

    def package(self):
        self.copy('build_options.txt')

    def package_id(self):
        del self.info.options.pkg_config

    def package_info(self):
        build_options = ConfigParser()
        if hasattr(self, 'package_folder'):
            build_options.read(os.path.join(self.package_folder, 'build_options.txt'))

        if 'pkg_config' in build_options:
            pkg_config_env = self.env
            build_sysroot=build_options['pkg_config'].get('sysroot', None)
            usage_sysroot=pkg_config_env.get('PKG_CONFIG_SYSROOT_DIR', None)
            if build_sysroot and (build_sysroot != usage_sysroot):
                self.output.warn("Inconsistent PKG_CONFIG_SYSROOT_DIR (%s != %s), forcing absolute paths" % (build_sysroot,usage_sysroot))
                pkg_config_env['PKG_CONFIG_SYSROOT_DIR'] = build_sysroot
                pkg_config_env['PKG_CONFIG_ALLOW_SYSTEM_CFLAGS'] = '1'
                pkg_config_env['PKG_CONFIG_ALLOW_SYSTEM_LIBS'] = '1'

            with tools.environment_append(pkg_config_env):
                pkg = tools.PkgConfig(build_options['pkg_config']['module'])
                self.cpp_info.includedirs = [remove_prefix(x,'-I') for x in pkg.cflags_only_I]
                self.cpp_info.libdirs = [remove_prefix(x,'-L') for x in pkg.libs_only_L]
                self.cpp_info.libs = [remove_prefix(x,'-l') for x in pkg.libs_only_l]
                self.cpp_info.defines = [remove_prefix(x,'-D') for x in pkg.cflags_only_other  if x.startswith('-D')]
                self.cpp_info.cflags = [x for x in pkg.cflags_only_other if not x.startswith('-D')]
                self.cpp_info.cppflags = [x for x in pkg.cflags_only_other if not x.startswith('-D')]
                self.cpp_info.sharedlinkflags = pkg.libs_only_other
                self.cpp_info.exelinkflags = pkg.libs_only_other