installd: clear existing snapshots before performing a new one
Bug: 112431924
Test: installd_service_test
Change-Id: I23a97f113e8a7423a7c509ee06d1436a2c2c961f
diff --git a/cmds/installd/InstalldNativeService.cpp b/cmds/installd/InstalldNativeService.cpp
index 9e252ee..99f1a18 100644
--- a/cmds/installd/InstalldNativeService.cpp
+++ b/cmds/installd/InstalldNativeService.cpp
@@ -770,11 +770,6 @@
// TODO(narayan): For snapshotAppData as well as restoreAppDataSnapshot, we
// should validate that volumeUuid is either nullptr or TEST, we won't support
// anything else.
-//
-// TODO(narayan): We need to be clearer about the expected behaviour for the
-// case where a snapshot already exists. We either need to clear the contents
-// of the snapshot directory before we make a copy, or we need to ensure that
-// the caller always clears it before requesting a snapshot.
binder::Status InstalldNativeService::snapshotAppData(
const std::unique_ptr<std::string>& volumeUuid,
const std::string& packageName, int32_t user, int32_t storageFlags) {
@@ -819,6 +814,12 @@
auto from = create_data_user_de_package_path(volume_uuid, user, package_name);
auto to = create_data_misc_de_rollback_path(volume_uuid, user);
+ int rd = delete_dir_contents(to, true /* ignore_if_missing */);
+ if (rd != 0) {
+ res = error(rd, "Failed clearing existing snapshot " + to);
+ return res;
+ }
+
int rc = copy_directory_recursive(from.c_str(), to.c_str());
if (rc != 0) {
res = error(rc, "Failed copying " + from + " to " + to);
@@ -830,6 +831,13 @@
if (storageFlags & FLAG_STORAGE_CE) {
auto from = create_data_user_ce_package_path(volume_uuid, user, package_name);
auto to = create_data_misc_ce_rollback_path(volume_uuid, user);
+
+ int rd = delete_dir_contents(to, true /* ignore_if_missing */);
+ if (rd != 0) {
+ res = error(rd, "Failed clearing existing snapshot " + to);
+ return res;
+ }
+
int rc = copy_directory_recursive(from.c_str(), to.c_str());
if (rc != 0) {
res = error(rc, "Failed copying " + from + " to " + to);
diff --git a/cmds/installd/tests/installd_service_test.cpp b/cmds/installd/tests/installd_service_test.cpp
index 0d46341..6ded4b4 100644
--- a/cmds/installd/tests/installd_service_test.cpp
+++ b/cmds/installd/tests/installd_service_test.cpp
@@ -363,6 +363,55 @@
ASSERT_EQ(-1, stat((rollback_de_dir + "/com.foo").c_str(), &sb));
}
+TEST_F(ServiceTest, CreateAppDataSnapshot_ClearsExistingSnapshot) {
+ auto rollback_ce_dir = create_data_misc_ce_rollback_path("TEST", 0);
+ auto rollback_de_dir = create_data_misc_de_rollback_path("TEST", 0);
+
+ ASSERT_TRUE(mkdirs(rollback_ce_dir, 700));
+ ASSERT_TRUE(mkdirs(rollback_de_dir, 700));
+
+ auto fake_package_ce_path = create_data_user_ce_package_path("TEST", 0, "com.foo");
+ auto fake_package_de_path = create_data_user_de_package_path("TEST", 0, "com.foo");
+
+ ASSERT_TRUE(mkdirs(fake_package_ce_path, 700));
+ ASSERT_TRUE(mkdirs(fake_package_de_path, 700));
+
+ auto deleter = [&rollback_ce_dir, &rollback_de_dir,
+ &fake_package_ce_path, &fake_package_de_path]() {
+ delete_dir_contents(rollback_ce_dir, true);
+ delete_dir_contents(rollback_de_dir, true);
+ delete_dir_contents(fake_package_ce_path, true);
+ delete_dir_contents(fake_package_de_path, true);
+ rmdir(rollback_ce_dir.c_str());
+ rmdir(rollback_de_dir.c_str());
+ };
+ auto scope_guard = android::base::make_scope_guard(deleter);
+
+ // Simulate presence of an existing snapshot
+ ASSERT_TRUE(android::base::WriteStringToFile(
+ "TEST_CONTENT_CE", rollback_ce_dir + "/file1",
+ 0700, 10000, 20000, false /* follow_symlinks */));
+ ASSERT_TRUE(android::base::WriteStringToFile(
+ "TEST_CONTENT_DE", rollback_de_dir + "/file1",
+ 0700, 10000, 20000, false /* follow_symlinks */));
+
+ // Create app data.
+ ASSERT_TRUE(android::base::WriteStringToFile(
+ "TEST_CONTENT_2_CE", fake_package_ce_path + "/file2",
+ 0700, 10000, 20000, false /* follow_symlinks */));
+ ASSERT_TRUE(android::base::WriteStringToFile(
+ "TEST_CONTENT_2_DE", fake_package_de_path + "/file2",
+ 0700, 10000, 20000, false /* follow_symlinks */));
+
+ ASSERT_TRUE(service->snapshotAppData(std::make_unique<std::string>("TEST"),
+ "com.foo", 0, FLAG_STORAGE_DE | FLAG_STORAGE_CE).isOk());
+
+ // Previous snapshot (with data for file1) must be cleared.
+ struct stat sb;
+ ASSERT_EQ(-1, stat((rollback_ce_dir + "/com.foo/file1").c_str(), &sb));
+ ASSERT_EQ(-1, stat((rollback_de_dir + "/com.foo/file1").c_str(), &sb));
+}
+
TEST_F(ServiceTest, RestoreAppDataSnapshot) {
auto rollback_ce_dir = create_data_misc_ce_rollback_path("TEST", 0);
auto rollback_de_dir = create_data_misc_de_rollback_path("TEST", 0);