add function to traversal the crates

The system_server needs to traversal Context.getCratesDir() to get all
of crates. But, system_server doesn't have the permission. system_server
needs installd to traverse Context.getCratesDir().

The depth of traversal in Context.getCratesDir is 1. installd returns the
list CrateMetadata. CrateMetadata contains the following information.
* crateName: it is the folder name

To add .gitigTo add .gitignore to collect the ignore file list.

Test: atest \
        CtsOsTestCases:android.os.storage.cts.CrateInfoTest \
        CtsOsTestCases:android.os.storage.cts.StorageManagerCratesTest \
        CtsOsTestCases:android.os.storage.cts.StorageStatsManagerTest

Bug: 141660526
Change-Id: Iea5eee4606e4ff437edef617a1f8db93e37f51c4

1 files changed, 129 insertions, 0 deletions

diff --git a/cmds/installd/CrateManager.cpp b/cmds/installd/CrateManager.cpp
new file mode 100644
index 0000000000..344aefbcbe
--- /dev/null
+++ b/cmds/installd/CrateManager.cpp
@@ -0,0 +1,129 @@
+/*
+ * Copyright (C) 2019 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 "CrateManager.h"
+
+#include <android-base/logging.h>
+#include <android-base/stringprintf.h>
+#include <android/log.h>
+#include <errno.h>
+#include <inttypes.h>
+#include <libgen.h>
+#include <stdint.h>
+#include <string.h>
+#include <sys/xattr.h>
+#include <unistd.h>
+
+#include <fstream>
+#include <string>
+#include <utils.h>
+
+#include "utils.h"
+
+using android::base::StringPrintf;
+
+namespace android {
+namespace installd {
+
+CrateManager::CrateManager(const char* uuid, userid_t userId, const std::string& packageName) {
+    mPackageName = packageName;
+    mRoot = create_data_user_ce_package_path(uuid, userId, (const char*)packageName.c_str());
+    mCratedFoldersRoot = StringPrintf("%s/crates", mRoot.c_str());
+}
+
+CrateManager::~CrateManager() {}
+
+static std::string getValidatedCratedPath(std::string path) {
+    size_t pos = path.rfind("/");
+    if (pos == std::string::npos) {
+        return path;
+    }
+
+    return path.substr(pos + 1, path.length());
+}
+
+void CrateManager::traverseChildDir(const std::string& targetDir,
+    std::function<void(FTSENT*)>& onVisitChildDir) {
+    char* argv[] = {(char*)targetDir.c_str(), nullptr};
+    FTS* fts = fts_open(argv, FTS_PHYSICAL | FTS_NOCHDIR | FTS_XDEV, nullptr);
+    if (fts == nullptr) {
+        PLOG(WARNING) << "Failed to fts_open " << targetDir;
+        return;
+    }
+
+    FTSENT* p;
+    while ((p = fts_read(fts)) != nullptr) {
+        switch (p->fts_info) {
+            case FTS_D:
+                if (p->fts_level == 1) {
+                    onVisitChildDir(p);
+                }
+                break;
+            default:
+                break;
+        }
+
+        if (p->fts_level == 1) {
+            fts_set(fts, p, FTS_SKIP);
+        }
+    }
+    fts_close(fts);
+}
+
+void CrateManager::traverseAllPackagesForUser(
+        const std::unique_ptr<std::string>& uuid, userid_t userId,
+        std::function<void(FTSENT*)>& onHandlingPackage) {
+    const char* uuid_ = uuid ? uuid->c_str() : nullptr;
+
+    auto ce_path = create_data_user_ce_path(uuid_, userId);
+    traverseChildDir(ce_path, onHandlingPackage);
+}
+
+void CrateManager::createCrate(
+        CratedFolder cratedFolder,
+        std::function<void(CratedFolder, std::unique_ptr<CrateMetadata>&)>& onCreateCrate) {
+    const char* path = cratedFolder->fts_path;
+    if (path == nullptr || *path == '\0') {
+        return;
+    }
+
+    std::unique_ptr<CrateMetadata> crateMetadata = std::make_unique<CrateMetadata>();
+    crateMetadata->uid = cratedFolder->fts_statp->st_uid;
+    crateMetadata->packageName = mPackageName;
+    crateMetadata->id = getValidatedCratedPath(path);
+
+    onCreateCrate(cratedFolder, crateMetadata);
+}
+
+void CrateManager::traverseAllCrates(std::function<void(CratedFolder, std::unique_ptr<CrateMetadata>&)>& onCreateCrate) {
+    std::function<void(FTSENT*)> onVisitCrateDir = [&](FTSENT* cratedFolder) -> void {
+        createCrate(cratedFolder, onCreateCrate);
+    };
+    traverseChildDir(mCratedFoldersRoot, onVisitCrateDir);
+}
+
+#if CRATE_DEBUG
+void CrateManager::dump(std::unique_ptr<CrateMetadata>& CrateMetadata) {
+    LOG(DEBUG) << "CrateMetadata = {"
+            << "uid : \"" << CrateMetadata->uid
+            << "\", packageName : \"" << CrateMetadata->packageName
+            << "\", id : \"" << CrateMetadata->id
+            << "\"}";
+}
+#endif
+
+} // namespace installd
+} // namespace android