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

libprocessgroup/Android.bp

@@ -79,12 +79,12 @@ cc_library {
     ],
     static_libs: [
         "libjsoncpp",
+        "libprocessgroup_util",
     ],
     // for cutils/android_filesystem_config.h
     header_libs: [
         "libcutils_headers",
         "libprocessgroup_headers",
-        "libprocessgroup_util",
     ],
     export_include_dirs: ["include"],
     export_header_lib_headers: [

libprocessgroup/setup/Android.bp

@@ -34,10 +34,10 @@ cc_library_shared {
     ],
     static_libs: [
         "libcgrouprc_format",
+        "libprocessgroup_util",
     ],
     header_libs: [
         "libprocessgroup_headers",
-        "libprocessgroup_util",
     ],
     export_header_lib_headers: [
         "libprocessgroup_headers",

libprocessgroup/util/Android.bp

@@ -19,7 +19,7 @@ package {
     default_applicable_licenses: ["Android-Apache-2.0"],
 }
 
-cc_library_headers {
+cc_library_static {
     name: "libprocessgroup_util",
     vendor_available: true,
     product_available: true,
@@ -36,12 +36,15 @@ cc_library_headers {
     export_include_dirs: [
         "include",
     ],
+    srcs: [
+        "util.cpp",
+    ],
     defaults: ["libprocessgroup_build_flags_cc"],
 }
 
 cc_test {
     name: "libprocessgroup_util_test",
-    header_libs: ["libprocessgroup_util"],
+    static_libs: ["libprocessgroup_util"],
     srcs: ["tests/util.cpp"],
     test_suites: ["general-tests"],
 }

libprocessgroup/util/include/processgroup/util.h

@@ -16,46 +16,10 @@
 
 #pragma once
 
-#include <algorithm>
-#include <iterator>
 #include <string>
 
 namespace util {
 
-namespace internal {
-
-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;
-}
-
-}  // namespace internal
-
-unsigned int GetCgroupDepth(const std::string& controller_root, const std::string& cgroup_path) {
-    const std::string deduped_root = internal::DeduplicateAndTrimSeparators(controller_root);
-    const std::string deduped_path = internal::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(),
-                      internal::SEP);
-}
+unsigned int GetCgroupDepth(const std::string& controller_root, const std::string& cgroup_path);
 
 }  // namespace util

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