Team2890/allwpilib
4
0
Fork 0
mirror of https://github.com/wpilibsuite/allwpilib synced 2026-06-22 01:11:42 +00:00
Code Issues Packages Projects Releases Wiki Activity

Storage: Make setters globally atomic.

Browse Source 
Previously, setters were locally but not globally atomic because they
used GetEntry() (globally atomic) in conjunction with locally atomic
gets/sets to the StorageEntry.  To support synchronizing network handshakes
they need to be globally atomic.

GetEntry() has been removed due to this issue, so a helper was added to
StorageTest instead.
This commit is contained in:
Peter Johnson
2015-07-26 09:27:23 -07:00
parent 3c7cb363ba
commit 18659257d3
3 changed files with 34 additions and 31 deletions
Download Patch File Download Diff File Expand all files Collapse all files

21
src/Storage.cpp
View File

@@ -29,13 +29,6 @@ std::shared_ptr<StorageEntry> Storage::FindEntry(StringRef name) const {
return i == m_entries.end() ? nullptr : i->getValue();
}
std::shared_ptr<StorageEntry> Storage::GetEntry(StringRef name) {
std::lock_guard<std::mutex> lock(m_mutex);
auto& entry = m_entries[name];
if (!entry) entry = std::make_shared<StorageEntry>();
return entry;
}
std::shared_ptr<Value> Storage::GetEntryValue(StringRef name) const {
auto entry = FindEntry(name);
if (!entry) return nullptr;
@@ -45,7 +38,9 @@ std::shared_ptr<Value> Storage::GetEntryValue(StringRef name) const {
bool Storage::SetEntryValue(StringRef name, std::shared_ptr<Value> value) {
if (name.empty()) return true;
if (!value) return true;
auto entry = GetEntry(name);
std::lock_guard<std::mutex> lock(m_mutex);
auto& entry = m_entries[name];
if (!entry) entry = std::make_shared<StorageEntry>();
auto old_value = entry->value();
if (old_value && old_value->type() != value->type())
return false; // error on type mismatch
@@ -61,7 +56,9 @@ bool Storage::SetEntryValue(StringRef name, std::shared_ptr<Value> value) {
void Storage::SetEntryTypeValue(StringRef name, std::shared_ptr<Value> value) {
if (name.empty()) return;
if (!value) return;
auto entry = GetEntry(name);
std::lock_guard<std::mutex> lock(m_mutex);
auto& entry = m_entries[name];
if (!entry) entry = std::make_shared<StorageEntry>();
auto old_value = entry->value();
entry->set_value(value);
if (!old_value || *old_value != *value) {
@@ -75,8 +72,10 @@ void Storage::SetEntryTypeValue(StringRef name, std::shared_ptr<Value> value) {
void Storage::SetEntryFlags(StringRef name, unsigned int flags) {
if (name.empty()) return;
auto entry = FindEntry(name);
if (!entry) return;
std::lock_guard<std::mutex> lock(m_mutex);
auto i = m_entries.find(name);
if (i == m_entries.end()) return;
auto entry = i->getValue();
if (entry->flags() != flags) {
entry->set_flags(flags);
AddUpdate(entry, Update::kFlagsUpdate); // put on update queue