update_engine: Fix [Memory|File]Storage partial inconsistency
|Prefs::MemoryStorage| and |Prefs::FileStorage| had inconsistency when
dealing with operations through |StorageInterface|, this change keeps
the implementations more consistent. This keeps the underlying
|StorageInterface| impementations behaving as similar as can be whether
|[Memory|File]Storage| is used.
Passing a namespace to |Prefs::FileStorage| backed |Pref| is no longer
recursive in order to restrict to deleting keys.
To delete all keys within a namespace, callers can use
|Prefs::GetSubKeys(...)| and |Prefs::Delete(...)| accordingly.
BUG=chromium:928805
TEST=FEATURES=test emerge-$B update_engine
Change-Id: I3ea8b51e14b1405ca1cdef66f858a18d124ca0aa
Reviewed-on: https://chromium-review.googlesource.com/c/aosp/platform/system/update_engine/+/2195624
Tested-by: Jae Hoon Kim <kimjae@chromium.org>
Commit-Queue: Jae Hoon Kim <kimjae@chromium.org>
Reviewed-by: Amin Hassani <ahassani@chromium.org>
Reviewed-by: Andrew Lassalle <andrewlassalle@chromium.org>
diff --git a/common/prefs.cc b/common/prefs.cc
index 6db01b7..615014f 100644
--- a/common/prefs.cc
+++ b/common/prefs.cc
@@ -32,10 +32,10 @@
namespace chromeos_update_engine {
-const char kKeySeparator = '/';
-
namespace {
+const char kKeySeparator = '/';
+
void DeleteEmptyDirectories(const base::FilePath& path) {
base::FileEnumerator path_enum(
path, false /* recursive */, base::FileEnumerator::DIRECTORIES);
@@ -112,6 +112,10 @@
return true;
}
+bool PrefsBase::GetSubKeys(const string& ns, vector<string>* keys) const {
+ return storage_->GetSubKeys(ns, keys);
+}
+
void PrefsBase::AddObserver(const string& key, ObserverInterface* observer) {
observers_[key].push_back(observer);
}
@@ -150,6 +154,24 @@
return true;
}
+bool Prefs::FileStorage::GetSubKeys(const string& ns,
+ vector<string>* keys) const {
+ base::FilePath filename;
+ TEST_AND_RETURN_FALSE(GetFileNameForKey(ns, &filename));
+ base::FileEnumerator namespace_enum(
+ prefs_dir_, true, base::FileEnumerator::FILES);
+ for (base::FilePath f = namespace_enum.Next(); !f.empty();
+ f = namespace_enum.Next()) {
+ auto filename_str = filename.value();
+ if (f.value().compare(0, filename_str.length(), filename_str) == 0) {
+ // Only return the key portion excluding the |prefs_dir_| with slash.
+ keys->push_back(f.value().substr(
+ prefs_dir_.AsEndingWithSeparator().value().length()));
+ }
+ }
+ return true;
+}
+
bool Prefs::FileStorage::SetKey(const string& key, const string& value) {
base::FilePath filename;
TEST_AND_RETURN_FALSE(GetFileNameForKey(key, &filename));
@@ -172,19 +194,17 @@
bool Prefs::FileStorage::DeleteKey(const string& key) {
base::FilePath filename;
TEST_AND_RETURN_FALSE(GetFileNameForKey(key, &filename));
- TEST_AND_RETURN_FALSE(base::DeleteFile(filename, true));
+ TEST_AND_RETURN_FALSE(base::DeleteFile(filename, false));
return true;
}
bool Prefs::FileStorage::GetFileNameForKey(const string& key,
base::FilePath* filename) const {
- // Allows only non-empty keys containing [A-Za-z0-9_-].
+ // Allows only non-empty keys containing [A-Za-z0-9_-/].
TEST_AND_RETURN_FALSE(!key.empty());
- for (size_t i = 0; i < key.size(); ++i) {
- char c = key.at(i);
+ for (char c : key)
TEST_AND_RETURN_FALSE(base::IsAsciiAlpha(c) || base::IsAsciiDigit(c) ||
c == '_' || c == '-' || c == kKeySeparator);
- }
*filename = prefs_dir_.Append(key);
return true;
}
@@ -200,6 +220,24 @@
return true;
}
+bool MemoryPrefs::MemoryStorage::GetSubKeys(const string& ns,
+ vector<string>* keys) const {
+ using value_type = decltype(values_)::value_type;
+ using key_type = decltype(values_)::key_type;
+ auto lower_comp = [](const value_type& pr, const key_type& ns) {
+ return pr.first.substr(0, ns.length()) < ns;
+ };
+ auto upper_comp = [](const key_type& ns, const value_type& pr) {
+ return ns < pr.first.substr(0, ns.length());
+ };
+ auto lower_it =
+ std::lower_bound(begin(values_), end(values_), ns, lower_comp);
+ auto upper_it = std::upper_bound(lower_it, end(values_), ns, upper_comp);
+ while (lower_it != upper_it)
+ keys->push_back((lower_it++)->first);
+ return true;
+}
+
bool MemoryPrefs::MemoryStorage::SetKey(const string& key,
const string& value) {
values_[key] = value;