feat: initial integration behaviortreecpp (#13008)

This is an initial integration for BehaviorTree.CPP
([website](https://www.behaviortree.dev/),
[repo](https://github.com/BehaviorTree/BehaviorTree.CPP)) a popular
library that allows to e.g., structure the switching between different
tasks in an autonomous agent, such as a robot or a virtual entity in a
computer game.

This PR can be reviewed but needs to wait until the
BehaviorTree/BehaviorTree.CPP#925 PR is merged
and the harnesses land upstream.

Also, @facontidavide or @miccol either of you as a core-maintainer need
to agree on this onboarding of the project here, so if you do, please
just ACK this.

---------

Co-authored-by: cktii <[email protected]>

Author: cktii

projects/behaviortreecpp/Dockerfile

@@ -0,0 +1,21 @@
+# Copyright 2025 Google LLC
+#
+# 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 gcr.io/oss-fuzz-base/base-builder
+RUN apt-get update && apt-get install -y make autoconf automake libtool cmake pkg-config wget libsodium-dev
+RUN git clone --depth 1 https://github.com/BehaviorTree/BehaviorTree.CPP.git behaviortreecpp
+WORKDIR behaviortreecpp
+COPY build.sh $SRC/

projects/behaviortreecpp/build.sh

@@ -0,0 +1,56 @@
+#!/bin/bash -eu
+# Copyright 2025 Google LLC
+#
+# 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.
+#
+################################################################################
+
+# ===== BUILD Sqlite =====
+SQLITE_VER=sqlite-autoconf-3480000
+
+wget https://www.sqlite.org/2025/${SQLITE_VER}.tar.gz
+tar xzf ${SQLITE_VER}.tar.gz
+cd ${SQLITE_VER}
+./configure --enable-static --disable-shared
+make -j"$(nproc)"
+make install
+cd ..
+
+# ===== BUILD zeroMQ =====
+git clone https://github.com/zeromq/libzmq.git
+cd libzmq
+mkdir build && cd build
+cmake .. -DBUILD_SHARED=OFF -DBUILD_STATIC=ON -DZMQ_BUILD_TESTS=OFF
+make -j"$(nproc)"
+make install
+cd ../..
+
+# ===== Build BehaviorTree.CPP =====
+mkdir build && cd build
+
+CMAKE_FLAGS=(
+  "-DCMAKE_BUILD_TYPE=Release"
+  "-DENABLE_FUZZING=ON"
+  "-DFORCE_STATIC_LINKING=ON"
+)
+
+cmake .. "${CMAKE_FLAGS[@]}"
+make -j"$(nproc)"
+
+for fuzzer in bt_fuzzer script_fuzzer bb_fuzzer; do
+  cp $fuzzer "$OUT/"
+
+  if [ -d ../fuzzing/corpus/${fuzzer} ]; then
+    zip -j "$OUT/${fuzzer}_seed_corpus.zip" ../fuzzing/corpus/${fuzzer}/*
+  fi
+done

projects/behaviortreecpp/project.yaml

@@ -0,0 +1,13 @@
+homepage: "https://www.behaviortree.dev/"
+language: c++
+primary_contact: "[email protected]"
+main_repo: "https://github.com/BehaviorTree/BehaviorTree.CPP"
+file_github_issue: true
+vendor_ccs:
+  - "[email protected]"
+fuzzing_engines:
+  - libfuzzer
+  - afl
+sanitizers:
+  - address
+  - undefined