add drone config [ci skip]

.drone.star

@@ -0,0 +1,23 @@
+# Use, modification, and distribution are
+# subject to the Boost Software License, Version 1.0. (See accompanying
+# file LICENSE.txt)
+#
+# Copyright Rene Rivera 2020.
+
+# For Drone CI we use the Starlark scripting language to reduce duplication.
+# As the yaml syntax for Drone CI is rather limited.
+#
+#
+globalenv={}
+linuxglobalimage="cppalliance/droneubuntu1604:1"
+windowsglobalimage="cppalliance/dronevs2019"
+
+def main(ctx):
+  return [
+  linux_cxx("TOOLSET=gcc CXXSTD=03,11 Job 0", "g++", packages="", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'TOOLSET': 'gcc', 'CXXSTD': '03,11', 'DRONE_JOB_UUID': 'b6589fc6ab'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=clang CXXSTD=03,11,14,1z Job 1", "clang++", packages="", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'TOOLSET': 'clang', 'CXXSTD': '03,11,14,1z', 'DRONE_JOB_UUID': '356a192b79'}, globalenv=globalenv),
+  osx_cxx("TOOLSET=clang CXXSTD=03,11,14,1z Job 2", "clang++", packages="", buildtype="boost", buildscript="drone", environment={'TOOLSET': 'clang', 'CXXSTD': '03,11,14,1z', 'DRONE_JOB_UUID': 'da4b9237ba'}, globalenv=globalenv),
+    ]
+
+# from https://github.com/boostorg/boost-ci
+load("@boost_ci//ci/drone/:functions.star", "linux_cxx","windows_cxx","osx_cxx","freebsd_cxx")

.drone/drone.sh

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+#!/bin/bash
+
+# Copyright 2020 Rene Rivera, Sam Darwin
+# Distributed under the Boost Software License, Version 1.0.
+# (See accompanying file LICENSE.txt or copy at http://boost.org/LICENSE_1_0.txt)
+
+set -e
+export TRAVIS_BUILD_DIR=$(pwd)
+export DRONE_BUILD_DIR=$(pwd)
+export TRAVIS_BRANCH=$DRONE_BRANCH
+export VCS_COMMIT_ID=$DRONE_COMMIT
+export GIT_COMMIT=$DRONE_COMMIT
+export REPO_NAME=$DRONE_REPO
+export PATH=~/.local/bin:/usr/local/bin:$PATH
+
+if [ "$DRONE_JOB_BUILDTYPE" == "boost" ]; then
+
+echo '==================================> INSTALL'
+
+BOOST_BRANCH=develop && [ "$TRAVIS_BRANCH" == "master" ] && BOOST_BRANCH=master || true
+cd ..
+git clone -b $BOOST_BRANCH https://github.com/boostorg/boost.git boost-root
+cd boost-root
+git submodule update --init tools/build
+git submodule update --init libs/config
+git submodule update --init tools/boostdep
+cp -r $TRAVIS_BUILD_DIR/* libs/foreach
+python tools/boostdep/depinst/depinst.py foreach
+./bootstrap.sh
+./b2 headers
+
+echo '==================================> SCRIPT'
+
+./b2 libs/foreach/test toolset=$TOOLSET cxxstd=$CXXSTD
+
+fi