libprocessgroup: Convert libprocessgroup_util to static library
To avoid duplicate symbol linker error and prep for addition of json
descriptor reading and activation functions in upcoming changes.
Bug: 349105928
Test: m
Change-Id: I5cd663d6007ef330b872b8cf8ed046ee68b6d736
diff --git a/libprocessgroup/util/util.cpp b/libprocessgroup/util/util.cpp
new file mode 100644
index 0000000..9b88a22
--- /dev/null
+++ b/libprocessgroup/util/util.cpp
@@ -0,0 +1,59 @@
+/*
+ * Copyright (C) 2024 The Android Open Source Project
+ *
+ * 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.
+ */
+
+#include <processgroup/util.h>
+
+#include <algorithm>
+#include <iterator>
+
+namespace {
+
+const char SEP = '/';
+
+std::string DeduplicateAndTrimSeparators(const std::string& path) {
+ bool lastWasSep = false;
+ std::string ret;
+
+ std::copy_if(path.begin(), path.end(), std::back_inserter(ret), [&lastWasSep](char c) {
+ if (lastWasSep) {
+ if (c == SEP) return false;
+ lastWasSep = false;
+ } else if (c == SEP) {
+ lastWasSep = true;
+ }
+ return true;
+ });
+
+ if (ret.length() > 1 && ret.back() == SEP) ret.pop_back();
+
+ return ret;
+}
+
+} // anonymous namespace
+
+namespace util {
+
+unsigned int GetCgroupDepth(const std::string& controller_root, const std::string& cgroup_path) {
+ const std::string deduped_root = DeduplicateAndTrimSeparators(controller_root);
+ const std::string deduped_path = DeduplicateAndTrimSeparators(cgroup_path);
+
+ if (deduped_root.empty() || deduped_path.empty() || !deduped_path.starts_with(deduped_root))
+ return 0;
+
+ return std::count(deduped_path.begin() + deduped_root.size(), deduped_path.end(), SEP);
+}
+
+} // namespace util