1
0
Fork 0
mirror of https://github.com/DanielnetoDotCom/YouPHPTube synced 2025-10-03 09:49:28 +02:00
Oinktube/node_modules/leveldown/binding.cc

2058 lines
53 KiB
C++

#define NAPI_VERSION 3
#include <napi-macros.h>
#include <node_api.h>
#include <assert.h>
#include <leveldb/db.h>
#include <leveldb/write_batch.h>
#include <leveldb/cache.h>
#include <leveldb/filter_policy.h>
#include <map>
#include <vector>
/**
* Forward declarations.
*/
struct Database;
struct Iterator;
static void iterator_end_do (napi_env env, Iterator* iterator, napi_value cb);
/**
* Macros.
*/
#define NAPI_DB_CONTEXT() \
Database* database = NULL; \
NAPI_STATUS_THROWS(napi_get_value_external(env, argv[0], (void**)&database));
#define NAPI_ITERATOR_CONTEXT() \
Iterator* iterator = NULL; \
NAPI_STATUS_THROWS(napi_get_value_external(env, argv[0], (void**)&iterator));
#define NAPI_BATCH_CONTEXT() \
Batch* batch = NULL; \
NAPI_STATUS_THROWS(napi_get_value_external(env, argv[0], (void**)&batch));
#define NAPI_RETURN_UNDEFINED() \
return 0;
#define NAPI_UTF8_NEW(name, val) \
size_t name##_size = 0; \
NAPI_STATUS_THROWS(napi_get_value_string_utf8(env, val, NULL, 0, &name##_size)) \
char* name = new char[name##_size + 1]; \
NAPI_STATUS_THROWS(napi_get_value_string_utf8(env, val, name, name##_size + 1, &name##_size)) \
name[name##_size] = '\0';
#define NAPI_ARGV_UTF8_NEW(name, i) \
NAPI_UTF8_NEW(name, argv[i])
#define LD_STRING_OR_BUFFER_TO_COPY(env, from, to) \
char* to##Ch_ = 0; \
size_t to##Sz_ = 0; \
if (IsString(env, from)) { \
napi_get_value_string_utf8(env, from, NULL, 0, &to##Sz_); \
to##Ch_ = new char[to##Sz_ + 1]; \
napi_get_value_string_utf8(env, from, to##Ch_, to##Sz_ + 1, &to##Sz_); \
to##Ch_[to##Sz_] = '\0'; \
} else if (IsBuffer(env, from)) { \
char* buf = 0; \
napi_get_buffer_info(env, from, (void **)&buf, &to##Sz_); \
to##Ch_ = new char[to##Sz_]; \
memcpy(to##Ch_, buf, to##Sz_); \
}
/*********************************************************************
* Helpers.
********************************************************************/
/**
* Returns true if 'value' is a string.
*/
static bool IsString (napi_env env, napi_value value) {
napi_valuetype type;
napi_typeof(env, value, &type);
return type == napi_string;
}
/**
* Returns true if 'value' is a buffer.
*/
static bool IsBuffer (napi_env env, napi_value value) {
bool isBuffer;
napi_is_buffer(env, value, &isBuffer);
return isBuffer;
}
/**
* Returns true if 'value' is an object.
*/
static bool IsObject (napi_env env, napi_value value) {
napi_valuetype type;
napi_typeof(env, value, &type);
return type == napi_object;
}
/**
* Create an error object.
*/
static napi_value CreateError (napi_env env, const char* str) {
napi_value msg;
napi_create_string_utf8(env, str, strlen(str), &msg);
napi_value error;
napi_create_error(env, NULL, msg, &error);
return error;
}
/**
* Returns true if 'obj' has a property 'key'.
*/
static bool HasProperty (napi_env env, napi_value obj, const char* key) {
bool has = false;
napi_has_named_property(env, obj, key, &has);
return has;
}
/**
* Returns a property in napi_value form.
*/
static napi_value GetProperty (napi_env env, napi_value obj, const char* key) {
napi_value value;
napi_get_named_property(env, obj, key, &value);
return value;
}
/**
* Returns a boolean property 'key' from 'obj'.
* Returns 'DEFAULT' if the property doesn't exist.
*/
static bool BooleanProperty (napi_env env, napi_value obj, const char* key,
bool DEFAULT) {
if (HasProperty(env, obj, key)) {
napi_value value = GetProperty(env, obj, key);
bool result;
napi_get_value_bool(env, value, &result);
return result;
}
return DEFAULT;
}
/**
* Returns a uint32 property 'key' from 'obj'.
* Returns 'DEFAULT' if the property doesn't exist.
*/
static uint32_t Uint32Property (napi_env env, napi_value obj, const char* key,
uint32_t DEFAULT) {
if (HasProperty(env, obj, key)) {
napi_value value = GetProperty(env, obj, key);
uint32_t result;
napi_get_value_uint32(env, value, &result);
return result;
}
return DEFAULT;
}
/**
* Returns a int32 property 'key' from 'obj'.
* Returns 'DEFAULT' if the property doesn't exist.
*/
static int Int32Property (napi_env env, napi_value obj, const char* key,
int DEFAULT) {
if (HasProperty(env, obj, key)) {
napi_value value = GetProperty(env, obj, key);
int result;
napi_get_value_int32(env, value, &result);
return result;
}
return DEFAULT;
}
/**
* Returns a string property 'key' from 'obj'.
* Returns empty string if the property doesn't exist.
*/
static std::string StringProperty (napi_env env, napi_value obj, const char* key) {
if (HasProperty(env, obj, key)) {
napi_value value = GetProperty(env, obj, key);
if (IsString(env, value)) {
size_t size = 0;
napi_get_value_string_utf8(env, value, NULL, 0, &size);
char* buf = new char[size + 1];
napi_get_value_string_utf8(env, value, buf, size + 1, &size);
buf[size] = '\0';
std::string result = buf;
delete [] buf;
return result;
}
}
return "";
}
static void DisposeSliceBuffer (leveldb::Slice slice) {
if (!slice.empty()) delete [] slice.data();
}
/**
* Convert a napi_value to a leveldb::Slice.
*/
static leveldb::Slice ToSlice (napi_env env, napi_value from) {
LD_STRING_OR_BUFFER_TO_COPY(env, from, to);
return leveldb::Slice(toCh_, toSz_);
}
/**
* Returns length of string or buffer
*/
static size_t StringOrBufferLength (napi_env env, napi_value value) {
size_t size = 0;
if (IsString(env, value)) {
napi_get_value_string_utf8(env, value, NULL, 0, &size);
} else if (IsBuffer(env, value)) {
char* buf;
napi_get_buffer_info(env, value, (void **)&buf, &size);
}
return size;
}
/**
* Takes a Buffer or string property 'name' from 'opts'.
* Returns null if the property does not exist or is zero-length.
*/
static std::string* RangeOption (napi_env env, napi_value opts, const char* name) {
if (HasProperty(env, opts, name)) {
napi_value value = GetProperty(env, opts, name);
if (StringOrBufferLength(env, value) > 0) {
LD_STRING_OR_BUFFER_TO_COPY(env, value, to);
std::string* result = new std::string(toCh_, toSz_);
delete [] toCh_;
return result;
}
}
return NULL;
}
/**
* Converts an array containing Buffer or string keys to a vector.
* Empty elements are skipped.
*/
static std::vector<std::string>* KeyArray (napi_env env, napi_value arr) {
uint32_t length;
std::vector<std::string>* result = new std::vector<std::string>();
if (napi_get_array_length(env, arr, &length) == napi_ok) {
result->reserve(length);
for (uint32_t i = 0; i < length; i++) {
napi_value element;
if (napi_get_element(env, arr, i, &element) == napi_ok &&
StringOrBufferLength(env, element) > 0) {
LD_STRING_OR_BUFFER_TO_COPY(env, element, to);
result->emplace_back(toCh_, toSz_);
delete [] toCh_;
}
}
}
return result;
}
/**
* Calls a function.
*/
static napi_status CallFunction (napi_env env,
napi_value callback,
const int argc,
napi_value* argv) {
napi_value global;
napi_get_global(env, &global);
return napi_call_function(env, global, callback, argc, argv, NULL);
}
/**
* Whether to yield entries, keys or values.
*/
enum Mode {
entries,
keys,
values
};
/**
* Helper struct for caching and converting a key-value pair to napi_values.
*/
struct Entry {
Entry (const leveldb::Slice* key, const leveldb::Slice* value) {
key_ = key != NULL ? new std::string(key->data(), key->size()) : NULL;
value_ = value != NULL ? new std::string(value->data(), value->size()) : NULL;
}
~Entry () {
if (key_ != NULL) delete key_;
if (value_ != NULL) delete value_;
}
// Not used yet.
void ConvertXX (napi_env env, Mode mode, bool keyAsBuffer, bool valueAsBuffer, napi_value* result) {
if (mode == Mode::entries) {
napi_create_array_with_length(env, 2, result);
napi_value valueElement;
napi_value keyElement;
Convert(env, key_, keyAsBuffer, &keyElement);
Convert(env, value_, valueAsBuffer, &valueElement);
napi_set_element(env, *result, 0, keyElement);
napi_set_element(env, *result, 1, valueElement);
} else if (mode == Mode::keys) {
Convert(env, key_, keyAsBuffer, result);
} else {
Convert(env, value_, valueAsBuffer, result);
}
}
static void Convert (napi_env env, const std::string* s, bool asBuffer, napi_value* result) {
if (s == NULL) {
napi_get_undefined(env, result);
} else if (asBuffer) {
napi_create_buffer_copy(env, s->size(), s->data(), NULL, result);
} else {
napi_create_string_utf8(env, s->data(), s->size(), result);
}
}
private:
std::string* key_;
std::string* value_;
};
/**
* Base worker class. Handles the async work. Derived classes can override the
* following virtual methods (listed in the order in which they're called):
*
* - DoExecute (abstract, worker pool thread): main work
* - HandleOKCallback (main thread): call JS callback on success
* - HandleErrorCallback (main thread): call JS callback on error
* - DoFinally (main thread): do cleanup regardless of success
*/
struct BaseWorker {
// Note: storing env is discouraged as we'd end up using it in unsafe places.
BaseWorker (napi_env env,
Database* database,
napi_value callback,
const char* resourceName)
: database_(database), errMsg_(NULL) {
NAPI_STATUS_THROWS_VOID(napi_create_reference(env, callback, 1, &callbackRef_));
napi_value asyncResourceName;
NAPI_STATUS_THROWS_VOID(napi_create_string_utf8(env, resourceName,
NAPI_AUTO_LENGTH,
&asyncResourceName));
NAPI_STATUS_THROWS_VOID(napi_create_async_work(env, callback,
asyncResourceName,
BaseWorker::Execute,
BaseWorker::Complete,
this, &asyncWork_));
}
virtual ~BaseWorker () {
delete [] errMsg_;
}
static void Execute (napi_env env, void* data) {
BaseWorker* self = (BaseWorker*)data;
// Don't pass env to DoExecute() because use of Node-API
// methods should generally be avoided in async work.
self->DoExecute();
}
bool SetStatus (leveldb::Status status) {
status_ = status;
if (!status.ok()) {
SetErrorMessage(status.ToString().c_str());
return false;
}
return true;
}
void SetErrorMessage(const char *msg) {
delete [] errMsg_;
size_t size = strlen(msg) + 1;
errMsg_ = new char[size];
memcpy(errMsg_, msg, size);
}
virtual void DoExecute () = 0;
static void Complete (napi_env env, napi_status status, void* data) {
BaseWorker* self = (BaseWorker*)data;
self->DoComplete(env);
self->DoFinally(env);
}
void DoComplete (napi_env env) {
napi_value callback;
napi_get_reference_value(env, callbackRef_, &callback);
if (status_.ok()) {
HandleOKCallback(env, callback);
} else {
HandleErrorCallback(env, callback);
}
}
virtual void HandleOKCallback (napi_env env, napi_value callback) {
napi_value argv;
napi_get_null(env, &argv);
CallFunction(env, callback, 1, &argv);
}
virtual void HandleErrorCallback (napi_env env, napi_value callback) {
napi_value argv = CreateError(env, errMsg_);
CallFunction(env, callback, 1, &argv);
}
virtual void DoFinally (napi_env env) {
napi_delete_reference(env, callbackRef_);
napi_delete_async_work(env, asyncWork_);
delete this;
}
void Queue (napi_env env) {
napi_queue_async_work(env, asyncWork_);
}
Database* database_;
private:
napi_ref callbackRef_;
napi_async_work asyncWork_;
leveldb::Status status_;
char *errMsg_;
};
/**
* Owns the LevelDB storage, cache, filter policy and iterators.
*/
struct Database {
Database ()
: db_(NULL),
blockCache_(NULL),
filterPolicy_(leveldb::NewBloomFilterPolicy(10)),
currentIteratorId_(0),
pendingCloseWorker_(NULL),
ref_(NULL),
priorityWork_(0) {}
~Database () {
if (db_ != NULL) {
delete db_;
db_ = NULL;
}
}
leveldb::Status Open (const leveldb::Options& options,
const char* location) {
return leveldb::DB::Open(options, location, &db_);
}
void CloseDatabase () {
delete db_;
db_ = NULL;
if (blockCache_) {
delete blockCache_;
blockCache_ = NULL;
}
}
leveldb::Status Put (const leveldb::WriteOptions& options,
leveldb::Slice key,
leveldb::Slice value) {
return db_->Put(options, key, value);
}
leveldb::Status Get (const leveldb::ReadOptions& options,
leveldb::Slice key,
std::string& value) {
return db_->Get(options, key, &value);
}
leveldb::Status Del (const leveldb::WriteOptions& options,
leveldb::Slice key) {
return db_->Delete(options, key);
}
leveldb::Status WriteBatch (const leveldb::WriteOptions& options,
leveldb::WriteBatch* batch) {
return db_->Write(options, batch);
}
uint64_t ApproximateSize (const leveldb::Range* range) {
uint64_t size = 0;
db_->GetApproximateSizes(range, 1, &size);
return size;
}
void CompactRange (const leveldb::Slice* start,
const leveldb::Slice* end) {
db_->CompactRange(start, end);
}
void GetProperty (const leveldb::Slice& property, std::string* value) {
db_->GetProperty(property, value);
}
const leveldb::Snapshot* NewSnapshot () {
return db_->GetSnapshot();
}
leveldb::Iterator* NewIterator (leveldb::ReadOptions* options) {
return db_->NewIterator(*options);
}
void ReleaseSnapshot (const leveldb::Snapshot* snapshot) {
return db_->ReleaseSnapshot(snapshot);
}
void AttachIterator (napi_env env, uint32_t id, Iterator* iterator) {
iterators_[id] = iterator;
IncrementPriorityWork(env);
}
void DetachIterator (napi_env env, uint32_t id) {
iterators_.erase(id);
DecrementPriorityWork(env);
}
void IncrementPriorityWork (napi_env env) {
napi_reference_ref(env, ref_, &priorityWork_);
}
void DecrementPriorityWork (napi_env env) {
napi_reference_unref(env, ref_, &priorityWork_);
if (priorityWork_ == 0 && pendingCloseWorker_ != NULL) {
pendingCloseWorker_->Queue(env);
pendingCloseWorker_ = NULL;
}
}
bool HasPriorityWork () const {
return priorityWork_ > 0;
}
leveldb::DB* db_;
leveldb::Cache* blockCache_;
const leveldb::FilterPolicy* filterPolicy_;
uint32_t currentIteratorId_;
BaseWorker *pendingCloseWorker_;
std::map< uint32_t, Iterator * > iterators_;
napi_ref ref_;
private:
uint32_t priorityWork_;
};
/**
* Base worker class for doing async work that defers closing the database.
*/
struct PriorityWorker : public BaseWorker {
PriorityWorker (napi_env env, Database* database, napi_value callback, const char* resourceName)
: BaseWorker(env, database, callback, resourceName) {
database_->IncrementPriorityWork(env);
}
virtual ~PriorityWorker () {}
void DoFinally (napi_env env) override {
database_->DecrementPriorityWork(env);
BaseWorker::DoFinally(env);
}
};
/**
* Owns a leveldb iterator.
*/
struct BaseIterator {
BaseIterator(Database* database,
const bool reverse,
std::string* lt,
std::string* lte,
std::string* gt,
std::string* gte,
const int limit,
const bool fillCache)
: database_(database),
hasEnded_(false),
didSeek_(false),
reverse_(reverse),
lt_(lt),
lte_(lte),
gt_(gt),
gte_(gte),
limit_(limit),
count_(0) {
options_ = new leveldb::ReadOptions();
options_->fill_cache = fillCache;
options_->snapshot = database->NewSnapshot();
dbIterator_ = database_->NewIterator(options_);
}
virtual ~BaseIterator () {
assert(hasEnded_);
if (lt_ != NULL) delete lt_;
if (gt_ != NULL) delete gt_;
if (lte_ != NULL) delete lte_;
if (gte_ != NULL) delete gte_;
delete options_;
}
bool DidSeek () const {
return didSeek_;
}
/**
* Seek to the first relevant key based on range options.
*/
void SeekToRange () {
didSeek_ = true;
if (!reverse_ && gte_ != NULL) {
dbIterator_->Seek(*gte_);
} else if (!reverse_ && gt_ != NULL) {
dbIterator_->Seek(*gt_);
if (dbIterator_->Valid() && dbIterator_->key().compare(*gt_) == 0) {
dbIterator_->Next();
}
} else if (reverse_ && lte_ != NULL) {
dbIterator_->Seek(*lte_);
if (!dbIterator_->Valid()) {
dbIterator_->SeekToLast();
} else if (dbIterator_->key().compare(*lte_) > 0) {
dbIterator_->Prev();
}
} else if (reverse_ && lt_ != NULL) {
dbIterator_->Seek(*lt_);
if (!dbIterator_->Valid()) {
dbIterator_->SeekToLast();
} else if (dbIterator_->key().compare(*lt_) >= 0) {
dbIterator_->Prev();
}
} else if (reverse_) {
dbIterator_->SeekToLast();
} else {
dbIterator_->SeekToFirst();
}
}
/**
* Seek manually (during iteration).
*/
void Seek (leveldb::Slice& target) {
didSeek_ = true;
if (OutOfRange(target)) {
return SeekToEnd();
}
dbIterator_->Seek(target);
if (dbIterator_->Valid()) {
int cmp = dbIterator_->key().compare(target);
if (reverse_ ? cmp > 0 : cmp < 0) {
Next();
}
} else {
SeekToFirst();
if (dbIterator_->Valid()) {
int cmp = dbIterator_->key().compare(target);
if (reverse_ ? cmp > 0 : cmp < 0) {
SeekToEnd();
}
}
}
}
void End () {
if (!hasEnded_) {
hasEnded_ = true;
delete dbIterator_;
dbIterator_ = NULL;
database_->ReleaseSnapshot(options_->snapshot);
}
}
bool Valid () const {
return dbIterator_->Valid() && !OutOfRange(dbIterator_->key());
}
bool Increment () {
return limit_ < 0 || ++count_ <= limit_;
}
void Next () {
if (reverse_) dbIterator_->Prev();
else dbIterator_->Next();
}
void SeekToFirst () {
if (reverse_) dbIterator_->SeekToLast();
else dbIterator_->SeekToFirst();
}
void SeekToLast () {
if (reverse_) dbIterator_->SeekToFirst();
else dbIterator_->SeekToLast();
}
void SeekToEnd () {
SeekToLast();
Next();
}
leveldb::Slice CurrentKey () const {
return dbIterator_->key();
}
leveldb::Slice CurrentValue () const {
return dbIterator_->value();
}
leveldb::Status Status () const {
return dbIterator_->status();
}
bool OutOfRange (const leveldb::Slice& target) const {
// TODO: benchmark to see if this is worth it
// if (upperBoundOnly && !reverse_) {
// return ((lt_ != NULL && target.compare(*lt_) >= 0) ||
// (lte_ != NULL && target.compare(*lte_) > 0));
// }
return ((lt_ != NULL && target.compare(*lt_) >= 0) ||
(lte_ != NULL && target.compare(*lte_) > 0) ||
(gt_ != NULL && target.compare(*gt_) <= 0) ||
(gte_ != NULL && target.compare(*gte_) < 0));
}
Database* database_;
bool hasEnded_;
private:
leveldb::Iterator* dbIterator_;
bool didSeek_;
const bool reverse_;
std::string* lt_;
std::string* lte_;
std::string* gt_;
std::string* gte_;
const int limit_;
int count_;
leveldb::ReadOptions* options_;
};
/**
* Extends BaseIterator for reading it from JS land.
*/
struct Iterator final : public BaseIterator {
Iterator (Database* database,
const uint32_t id,
const bool reverse,
const bool keys,
const bool values,
const int limit,
std::string* lt,
std::string* lte,
std::string* gt,
std::string* gte,
const bool fillCache,
const bool keyAsBuffer,
const bool valueAsBuffer,
const uint32_t highWaterMark)
: BaseIterator(database, reverse, lt, lte, gt, gte, limit, fillCache),
id_(id),
keys_(keys),
values_(values),
keyAsBuffer_(keyAsBuffer),
valueAsBuffer_(valueAsBuffer),
highWaterMark_(highWaterMark),
landed_(false),
nexting_(false),
isEnding_(false),
endWorker_(NULL),
ref_(NULL) {
}
~Iterator () {}
void Attach (napi_env env, napi_value context) {
napi_create_reference(env, context, 1, &ref_);
database_->AttachIterator(env, id_, this);
}
void Detach (napi_env env) {
database_->DetachIterator(env, id_);
if (ref_ != NULL) napi_delete_reference(env, ref_);
}
bool ReadMany (uint32_t size) {
cache_.clear();
size_t bytesRead = 0;
while (true) {
if (landed_) Next();
if (!Valid() || !Increment()) break;
if (keys_) {
leveldb::Slice slice = CurrentKey();
cache_.emplace_back(slice.data(), slice.size());
bytesRead += slice.size();
} else {
cache_.emplace_back("");
}
if (values_) {
leveldb::Slice slice = CurrentValue();
cache_.emplace_back(slice.data(), slice.size());
bytesRead += slice.size();
} else {
cache_.emplace_back("");
}
if (!landed_) {
landed_ = true;
return true;
}
if (bytesRead > highWaterMark_ || cache_.size() >= size * 2) {
return true;
}
}
return false;
}
const uint32_t id_;
const bool keys_;
const bool values_;
const bool keyAsBuffer_;
const bool valueAsBuffer_;
const uint32_t highWaterMark_;
bool landed_;
bool nexting_;
bool isEnding_;
BaseWorker* endWorker_;
std::vector<std::string> cache_;
private:
napi_ref ref_;
};
/**
* Hook for when the environment exits. This hook will be called after
* already-scheduled napi_async_work items have finished, which gives us
* the guarantee that no db operations will be in-flight at this time.
*/
static void env_cleanup_hook (void* arg) {
Database* database = (Database*)arg;
// Do everything that db_close() does but synchronously. We're expecting that GC
// did not (yet) collect the database because that would be a user mistake (not
// closing their db) made during the lifetime of the environment. That's different
// from an environment being torn down (like the main process or a worker thread)
// where it's our responsibility to clean up. Note also, the following code must
// be a safe noop if called before db_open() or after db_close().
if (database && database->db_ != NULL) {
std::map<uint32_t, Iterator*> iterators = database->iterators_;
std::map<uint32_t, Iterator*>::iterator it;
// TODO: does not do `napi_delete_reference(env, iterator->ref_)`. Problem?
for (it = iterators.begin(); it != iterators.end(); ++it) {
it->second->End();
}
// Having ended the iterators (and released snapshots) we can safely close.
database->CloseDatabase();
}
}
/**
* Runs when a Database is garbage collected.
*/
static void FinalizeDatabase (napi_env env, void* data, void* hint) {
if (data) {
Database* database = (Database*)data;
napi_remove_env_cleanup_hook(env, env_cleanup_hook, database);
if (database->ref_ != NULL) napi_delete_reference(env, database->ref_);
delete database;
}
}
/**
* Returns a context object for a database.
*/
NAPI_METHOD(db_init) {
Database* database = new Database();
napi_add_env_cleanup_hook(env, env_cleanup_hook, database);
napi_value result;
NAPI_STATUS_THROWS(napi_create_external(env, database,
FinalizeDatabase,
NULL, &result));
// Reference counter to prevent GC of database while priority workers are active
NAPI_STATUS_THROWS(napi_create_reference(env, result, 0, &database->ref_));
return result;
}
/**
* Worker class for opening a database.
* TODO: shouldn't this be a PriorityWorker?
*/
struct OpenWorker final : public BaseWorker {
OpenWorker (napi_env env,
Database* database,
napi_value callback,
const std::string& location,
const bool createIfMissing,
const bool errorIfExists,
const bool compression,
const uint32_t writeBufferSize,
const uint32_t blockSize,
const uint32_t maxOpenFiles,
const uint32_t blockRestartInterval,
const uint32_t maxFileSize)
: BaseWorker(env, database, callback, "leveldown.db.open"),
location_(location) {
options_.block_cache = database->blockCache_;
options_.filter_policy = database->filterPolicy_;
options_.create_if_missing = createIfMissing;
options_.error_if_exists = errorIfExists;
options_.compression = compression
? leveldb::kSnappyCompression
: leveldb::kNoCompression;
options_.write_buffer_size = writeBufferSize;
options_.block_size = blockSize;
options_.max_open_files = maxOpenFiles;
options_.block_restart_interval = blockRestartInterval;
options_.max_file_size = maxFileSize;
}
~OpenWorker () {}
void DoExecute () override {
SetStatus(database_->Open(options_, location_.c_str()));
}
leveldb::Options options_;
std::string location_;
};
/**
* Open a database.
*/
NAPI_METHOD(db_open) {
NAPI_ARGV(4);
NAPI_DB_CONTEXT();
NAPI_ARGV_UTF8_NEW(location, 1);
napi_value options = argv[2];
const bool createIfMissing = BooleanProperty(env, options, "createIfMissing", true);
const bool errorIfExists = BooleanProperty(env, options, "errorIfExists", false);
const bool compression = BooleanProperty(env, options, "compression", true);
const uint32_t cacheSize = Uint32Property(env, options, "cacheSize", 8 << 20);
const uint32_t writeBufferSize = Uint32Property(env, options , "writeBufferSize" , 4 << 20);
const uint32_t blockSize = Uint32Property(env, options, "blockSize", 4096);
const uint32_t maxOpenFiles = Uint32Property(env, options, "maxOpenFiles", 1000);
const uint32_t blockRestartInterval = Uint32Property(env, options,
"blockRestartInterval", 16);
const uint32_t maxFileSize = Uint32Property(env, options, "maxFileSize", 2 << 20);
database->blockCache_ = leveldb::NewLRUCache(cacheSize);
napi_value callback = argv[3];
OpenWorker* worker = new OpenWorker(env, database, callback, location,
createIfMissing, errorIfExists,
compression, writeBufferSize, blockSize,
maxOpenFiles, blockRestartInterval,
maxFileSize);
worker->Queue(env);
delete [] location;
NAPI_RETURN_UNDEFINED();
}
/**
* Worker class for closing a database
*/
struct CloseWorker final : public BaseWorker {
CloseWorker (napi_env env,
Database* database,
napi_value callback)
: BaseWorker(env, database, callback, "leveldown.db.close") {}
~CloseWorker () {}
void DoExecute () override {
database_->CloseDatabase();
}
};
napi_value noop_callback (napi_env env, napi_callback_info info) {
return 0;
}
/**
* Close a database.
*/
NAPI_METHOD(db_close) {
NAPI_ARGV(2);
NAPI_DB_CONTEXT();
napi_value callback = argv[1];
CloseWorker* worker = new CloseWorker(env, database, callback);
if (!database->HasPriorityWork()) {
worker->Queue(env);
NAPI_RETURN_UNDEFINED();
}
database->pendingCloseWorker_ = worker;
napi_value noop;
napi_create_function(env, NULL, 0, noop_callback, NULL, &noop);
std::map<uint32_t, Iterator*> iterators = database->iterators_;
std::map<uint32_t, Iterator*>::iterator it;
for (it = iterators.begin(); it != iterators.end(); ++it) {
iterator_end_do(env, it->second, noop);
}
NAPI_RETURN_UNDEFINED();
}
/**
* Worker class for putting key/value to the database
*/
struct PutWorker final : public PriorityWorker {
PutWorker (napi_env env,
Database* database,
napi_value callback,
leveldb::Slice key,
leveldb::Slice value,
bool sync)
: PriorityWorker(env, database, callback, "leveldown.db.put"),
key_(key), value_(value) {
options_.sync = sync;
}
~PutWorker () {
DisposeSliceBuffer(key_);
DisposeSliceBuffer(value_);
}
void DoExecute () override {
SetStatus(database_->Put(options_, key_, value_));
}
leveldb::WriteOptions options_;
leveldb::Slice key_;
leveldb::Slice value_;
};
/**
* Puts a key and a value to a database.
*/
NAPI_METHOD(db_put) {
NAPI_ARGV(5);
NAPI_DB_CONTEXT();
leveldb::Slice key = ToSlice(env, argv[1]);
leveldb::Slice value = ToSlice(env, argv[2]);
bool sync = BooleanProperty(env, argv[3], "sync", false);
napi_value callback = argv[4];
PutWorker* worker = new PutWorker(env, database, callback, key, value, sync);
worker->Queue(env);
NAPI_RETURN_UNDEFINED();
}
/**
* Worker class for getting a value from a database.
*/
struct GetWorker final : public PriorityWorker {
GetWorker (napi_env env,
Database* database,
napi_value callback,
leveldb::Slice key,
const bool asBuffer,
const bool fillCache)
: PriorityWorker(env, database, callback, "leveldown.db.get"),
key_(key),
asBuffer_(asBuffer) {
options_.fill_cache = fillCache;
}
~GetWorker () {
DisposeSliceBuffer(key_);
}
void DoExecute () override {
SetStatus(database_->Get(options_, key_, value_));
}
void HandleOKCallback (napi_env env, napi_value callback) override {
napi_value argv[2];
napi_get_null(env, &argv[0]);
Entry::Convert(env, &value_, asBuffer_, &argv[1]);
CallFunction(env, callback, 2, argv);
}
private:
leveldb::ReadOptions options_;
leveldb::Slice key_;
std::string value_;
const bool asBuffer_;
};
/**
* Gets a value from a database.
*/
NAPI_METHOD(db_get) {
NAPI_ARGV(4);
NAPI_DB_CONTEXT();
leveldb::Slice key = ToSlice(env, argv[1]);
napi_value options = argv[2];
const bool asBuffer = BooleanProperty(env, options, "asBuffer", true);
const bool fillCache = BooleanProperty(env, options, "fillCache", true);
napi_value callback = argv[3];
GetWorker* worker = new GetWorker(env, database, callback, key, asBuffer,
fillCache);
worker->Queue(env);
NAPI_RETURN_UNDEFINED();
}
/**
* Worker class for getting many values.
*/
struct GetManyWorker final : public PriorityWorker {
GetManyWorker (napi_env env,
Database* database,
const std::vector<std::string>* keys,
napi_value callback,
const bool valueAsBuffer,
const bool fillCache)
: PriorityWorker(env, database, callback, "leveldown.get.many"),
keys_(keys), valueAsBuffer_(valueAsBuffer) {
options_.fill_cache = fillCache;
options_.snapshot = database->NewSnapshot();
}
~GetManyWorker() {
delete keys_;
}
void DoExecute () override {
cache_.reserve(keys_->size());
for (const std::string& key: *keys_) {
std::string* value = new std::string();
leveldb::Status status = database_->Get(options_, key, *value);
if (status.ok()) {
cache_.push_back(value);
} else if (status.IsNotFound()) {
delete value;
cache_.push_back(NULL);
} else {
delete value;
for (const std::string* value: cache_) {
if (value != NULL) delete value;
}
SetStatus(status);
break;
}
}
database_->ReleaseSnapshot(options_.snapshot);
}
void HandleOKCallback (napi_env env, napi_value callback) override {
size_t size = cache_.size();
napi_value array;
napi_create_array_with_length(env, size, &array);
for (size_t idx = 0; idx < size; idx++) {
std::string* value = cache_[idx];
napi_value element;
Entry::Convert(env, value, valueAsBuffer_, &element);
napi_set_element(env, array, static_cast<uint32_t>(idx), element);
if (value != NULL) delete value;
}
napi_value argv[2];
napi_get_null(env, &argv[0]);
argv[1] = array;
CallFunction(env, callback, 2, argv);
}
private:
leveldb::ReadOptions options_;
const std::vector<std::string>* keys_;
const bool valueAsBuffer_;
std::vector<std::string*> cache_;
};
/**
* Gets many values from a database.
*/
NAPI_METHOD(db_get_many) {
NAPI_ARGV(4);
NAPI_DB_CONTEXT();
const std::vector<std::string>* keys = KeyArray(env, argv[1]);
napi_value options = argv[2];
const bool asBuffer = BooleanProperty(env, options, "asBuffer", true);
const bool fillCache = BooleanProperty(env, options, "fillCache", true);
napi_value callback = argv[3];
GetManyWorker* worker = new GetManyWorker(
env, database, keys, callback, asBuffer, fillCache
);
worker->Queue(env);
NAPI_RETURN_UNDEFINED();
}
/**
* Worker class for deleting a value from a database.
*/
struct DelWorker final : public PriorityWorker {
DelWorker (napi_env env,
Database* database,
napi_value callback,
leveldb::Slice key,
bool sync)
: PriorityWorker(env, database, callback, "leveldown.db.del"),
key_(key) {
options_.sync = sync;
}
~DelWorker () {
DisposeSliceBuffer(key_);
}
void DoExecute () override {
SetStatus(database_->Del(options_, key_));
}
leveldb::WriteOptions options_;
leveldb::Slice key_;
};
/**
* Delete a value from a database.
*/
NAPI_METHOD(db_del) {
NAPI_ARGV(4);
NAPI_DB_CONTEXT();
leveldb::Slice key = ToSlice(env, argv[1]);
bool sync = BooleanProperty(env, argv[2], "sync", false);
napi_value callback = argv[3];
DelWorker* worker = new DelWorker(env, database, callback, key, sync);
worker->Queue(env);
NAPI_RETURN_UNDEFINED();
}
/**
* Worker class for deleting a range from a database.
*/
struct ClearWorker final : public PriorityWorker {
ClearWorker (napi_env env,
Database* database,
napi_value callback,
const bool reverse,
const int limit,
std::string* lt,
std::string* lte,
std::string* gt,
std::string* gte)
: PriorityWorker(env, database, callback, "leveldown.db.clear") {
iterator_ = new BaseIterator(database, reverse, lt, lte, gt, gte, limit, false);
writeOptions_ = new leveldb::WriteOptions();
writeOptions_->sync = false;
}
~ClearWorker () {
delete iterator_;
delete writeOptions_;
}
void DoExecute () override {
iterator_->SeekToRange();
// TODO: add option
uint32_t hwm = 16 * 1024;
leveldb::WriteBatch batch;
while (true) {
size_t bytesRead = 0;
while (bytesRead <= hwm && iterator_->Valid() && iterator_->Increment()) {
leveldb::Slice key = iterator_->CurrentKey();
batch.Delete(key);
bytesRead += key.size();
iterator_->Next();
}
if (!SetStatus(iterator_->Status()) || bytesRead == 0) {
break;
}
if (!SetStatus(database_->WriteBatch(*writeOptions_, &batch))) {
break;
}
batch.Clear();
}
iterator_->End();
}
private:
BaseIterator* iterator_;
leveldb::WriteOptions* writeOptions_;
};
/**
* Delete a range from a database.
*/
NAPI_METHOD(db_clear) {
NAPI_ARGV(3);
NAPI_DB_CONTEXT();
napi_value options = argv[1];
napi_value callback = argv[2];
const bool reverse = BooleanProperty(env, options, "reverse", false);
const int limit = Int32Property(env, options, "limit", -1);
std::string* lt = RangeOption(env, options, "lt");
std::string* lte = RangeOption(env, options, "lte");
std::string* gt = RangeOption(env, options, "gt");
std::string* gte = RangeOption(env, options, "gte");
ClearWorker* worker = new ClearWorker(env, database, callback, reverse, limit, lt, lte, gt, gte);
worker->Queue(env);
NAPI_RETURN_UNDEFINED();
}
/**
* Worker class for calculating the size of a range.
*/
struct ApproximateSizeWorker final : public PriorityWorker {
ApproximateSizeWorker (napi_env env,
Database* database,
napi_value callback,
leveldb::Slice start,
leveldb::Slice end)
: PriorityWorker(env, database, callback, "leveldown.db.approximate_size"),
start_(start), end_(end) {}
~ApproximateSizeWorker () {
DisposeSliceBuffer(start_);
DisposeSliceBuffer(end_);
}
void DoExecute () override {
leveldb::Range range(start_, end_);
size_ = database_->ApproximateSize(&range);
}
void HandleOKCallback (napi_env env, napi_value callback) override {
napi_value argv[2];
napi_get_null(env, &argv[0]);
napi_create_int64(env, (uint64_t)size_, &argv[1]);
CallFunction(env, callback, 2, argv);
}
leveldb::Slice start_;
leveldb::Slice end_;
uint64_t size_;
};
/**
* Calculates the approximate size of a range in a database.
*/
NAPI_METHOD(db_approximate_size) {
NAPI_ARGV(4);
NAPI_DB_CONTEXT();
leveldb::Slice start = ToSlice(env, argv[1]);
leveldb::Slice end = ToSlice(env, argv[2]);
napi_value callback = argv[3];
ApproximateSizeWorker* worker = new ApproximateSizeWorker(env, database,
callback, start,
end);
worker->Queue(env);
NAPI_RETURN_UNDEFINED();
}
/**
* Worker class for compacting a range in a database.
*/
struct CompactRangeWorker final : public PriorityWorker {
CompactRangeWorker (napi_env env,
Database* database,
napi_value callback,
leveldb::Slice start,
leveldb::Slice end)
: PriorityWorker(env, database, callback, "leveldown.db.compact_range"),
start_(start), end_(end) {}
~CompactRangeWorker () {
DisposeSliceBuffer(start_);
DisposeSliceBuffer(end_);
}
void DoExecute () override {
database_->CompactRange(&start_, &end_);
}
leveldb::Slice start_;
leveldb::Slice end_;
};
/**
* Compacts a range in a database.
*/
NAPI_METHOD(db_compact_range) {
NAPI_ARGV(4);
NAPI_DB_CONTEXT();
leveldb::Slice start = ToSlice(env, argv[1]);
leveldb::Slice end = ToSlice(env, argv[2]);
napi_value callback = argv[3];
CompactRangeWorker* worker = new CompactRangeWorker(env, database, callback,
start, end);
worker->Queue(env);
NAPI_RETURN_UNDEFINED();
}
/**
* Get a property from a database.
*/
NAPI_METHOD(db_get_property) {
NAPI_ARGV(2);
NAPI_DB_CONTEXT();
leveldb::Slice property = ToSlice(env, argv[1]);
std::string value;
database->GetProperty(property, &value);
napi_value result;
napi_create_string_utf8(env, value.data(), value.size(), &result);
DisposeSliceBuffer(property);
return result;
}
/**
* Worker class for destroying a database.
*/
struct DestroyWorker final : public BaseWorker {
DestroyWorker (napi_env env,
const std::string& location,
napi_value callback)
: BaseWorker(env, NULL, callback, "leveldown.destroy_db"),
location_(location) {}
~DestroyWorker () {}
void DoExecute () override {
leveldb::Options options;
SetStatus(leveldb::DestroyDB(location_, options));
}
std::string location_;
};
/**
* Destroys a database.
*/
NAPI_METHOD(destroy_db) {
NAPI_ARGV(2);
NAPI_ARGV_UTF8_NEW(location, 0);
napi_value callback = argv[1];
DestroyWorker* worker = new DestroyWorker(env, location, callback);
worker->Queue(env);
delete [] location;
NAPI_RETURN_UNDEFINED();
}
/**
* Worker class for repairing a database.
*/
struct RepairWorker final : public BaseWorker {
RepairWorker (napi_env env,
const std::string& location,
napi_value callback)
: BaseWorker(env, NULL, callback, "leveldown.repair_db"),
location_(location) {}
~RepairWorker () {}
void DoExecute () override {
leveldb::Options options;
SetStatus(leveldb::RepairDB(location_, options));
}
std::string location_;
};
/**
* Repairs a database.
*/
NAPI_METHOD(repair_db) {
NAPI_ARGV(2);
NAPI_ARGV_UTF8_NEW(location, 0);
napi_value callback = argv[1];
RepairWorker* worker = new RepairWorker(env, location, callback);
worker->Queue(env);
delete [] location;
NAPI_RETURN_UNDEFINED();
}
/**
* Runs when an Iterator is garbage collected.
*/
static void FinalizeIterator (napi_env env, void* data, void* hint) {
if (data) {
delete (Iterator*)data;
}
}
/**
* Create an iterator.
*/
NAPI_METHOD(iterator_init) {
NAPI_ARGV(2);
NAPI_DB_CONTEXT();
napi_value options = argv[1];
const bool reverse = BooleanProperty(env, options, "reverse", false);
const bool keys = BooleanProperty(env, options, "keys", true);
const bool values = BooleanProperty(env, options, "values", true);
const bool fillCache = BooleanProperty(env, options, "fillCache", false);
const bool keyAsBuffer = BooleanProperty(env, options, "keyAsBuffer", true);
const bool valueAsBuffer = BooleanProperty(env, options, "valueAsBuffer", true);
const int limit = Int32Property(env, options, "limit", -1);
const uint32_t highWaterMark = Uint32Property(env, options, "highWaterMark",
16 * 1024);
std::string* lt = RangeOption(env, options, "lt");
std::string* lte = RangeOption(env, options, "lte");
std::string* gt = RangeOption(env, options, "gt");
std::string* gte = RangeOption(env, options, "gte");
const uint32_t id = database->currentIteratorId_++;
Iterator* iterator = new Iterator(database, id, reverse, keys,
values, limit, lt, lte, gt, gte, fillCache,
keyAsBuffer, valueAsBuffer, highWaterMark);
napi_value result;
NAPI_STATUS_THROWS(napi_create_external(env, iterator,
FinalizeIterator,
NULL, &result));
// Prevent GC of JS object before the iterator is ended (explicitly or on
// db close) and keep track of non-ended iterators to end them on db close.
iterator->Attach(env, result);
return result;
}
/**
* Seeks an iterator.
*/
NAPI_METHOD(iterator_seek) {
NAPI_ARGV(2);
NAPI_ITERATOR_CONTEXT();
if (iterator->isEnding_ || iterator->hasEnded_) {
napi_throw_error(env, NULL, "iterator has ended");
}
leveldb::Slice target = ToSlice(env, argv[1]);
iterator->landed_ = false;
iterator->Seek(target);
DisposeSliceBuffer(target);
NAPI_RETURN_UNDEFINED();
}
/**
* Worker class for ending an iterator
*/
struct EndWorker final : public BaseWorker {
EndWorker (napi_env env,
Iterator* iterator,
napi_value callback)
: BaseWorker(env, iterator->database_, callback, "leveldown.iterator.end"),
iterator_(iterator) {}
~EndWorker () {}
void DoExecute () override {
iterator_->End();
}
void DoFinally (napi_env env) override {
iterator_->Detach(env);
BaseWorker::DoFinally(env);
}
private:
Iterator* iterator_;
};
/**
* Called by NAPI_METHOD(iterator_end) and also when closing
* open iterators during NAPI_METHOD(db_close).
*/
static void iterator_end_do (napi_env env, Iterator* iterator, napi_value cb) {
if (!iterator->isEnding_ && !iterator->hasEnded_) {
EndWorker* worker = new EndWorker(env, iterator, cb);
iterator->isEnding_ = true;
if (iterator->nexting_) {
iterator->endWorker_ = worker;
} else {
worker->Queue(env);
}
}
}
/**
* Ends an iterator.
*/
NAPI_METHOD(iterator_end) {
NAPI_ARGV(2);
NAPI_ITERATOR_CONTEXT();
iterator_end_do(env, iterator, argv[1]);
NAPI_RETURN_UNDEFINED();
}
/**
* Worker class for nexting an iterator.
*/
struct NextWorker final : public BaseWorker {
NextWorker (napi_env env,
Iterator* iterator,
napi_value callback)
: BaseWorker(env, iterator->database_, callback,
"leveldown.iterator.next"),
iterator_(iterator), ok_() {}
~NextWorker () {}
void DoExecute () override {
if (!iterator_->DidSeek()) {
iterator_->SeekToRange();
}
// Limit the size of the cache to prevent starving the event loop
// in JS-land while we're recursively calling process.nextTick().
ok_ = iterator_->ReadMany(1000);
if (!ok_) {
SetStatus(iterator_->Status());
}
}
void HandleOKCallback (napi_env env, napi_value callback) override {
size_t arraySize = iterator_->cache_.size();
napi_value jsArray;
napi_create_array_with_length(env, arraySize, &jsArray);
for (size_t idx = 0; idx < iterator_->cache_.size(); idx += 2) {
std::string key = iterator_->cache_[idx];
std::string value = iterator_->cache_[idx + 1];
napi_value returnKey;
napi_value returnValue;
Entry::Convert(env, &key, iterator_->keyAsBuffer_, &returnKey);
Entry::Convert(env, &value, iterator_->valueAsBuffer_, &returnValue);
// put the key & value in a descending order, so that they can be .pop:ed in javascript-land
napi_set_element(env, jsArray, static_cast<int>(arraySize - idx - 1), returnKey);
napi_set_element(env, jsArray, static_cast<int>(arraySize - idx - 2), returnValue);
}
napi_value argv[3];
napi_get_null(env, &argv[0]);
argv[1] = jsArray;
napi_get_boolean(env, !ok_, &argv[2]);
CallFunction(env, callback, 3, argv);
}
void DoFinally (napi_env env) override {
// clean up & handle the next/end state
iterator_->nexting_ = false;
if (iterator_->endWorker_ != NULL) {
iterator_->endWorker_->Queue(env);
iterator_->endWorker_ = NULL;
}
BaseWorker::DoFinally(env);
}
private:
Iterator* iterator_;
bool ok_;
};
/**
* Moves an iterator to next element.
*/
NAPI_METHOD(iterator_next) {
NAPI_ARGV(2);
NAPI_ITERATOR_CONTEXT();
napi_value callback = argv[1];
if (iterator->isEnding_ || iterator->hasEnded_) {
napi_value argv = CreateError(env, "iterator has ended");
CallFunction(env, callback, 1, &argv);
NAPI_RETURN_UNDEFINED();
}
NextWorker* worker = new NextWorker(env, iterator, callback);
iterator->nexting_ = true;
worker->Queue(env);
NAPI_RETURN_UNDEFINED();
}
/**
* Worker class for batch write operation.
*/
struct BatchWorker final : public PriorityWorker {
BatchWorker (napi_env env,
Database* database,
napi_value callback,
leveldb::WriteBatch* batch,
const bool sync,
const bool hasData)
: PriorityWorker(env, database, callback, "leveldown.batch.do"),
batch_(batch), hasData_(hasData) {
options_.sync = sync;
}
~BatchWorker () {
delete batch_;
}
void DoExecute () override {
if (hasData_) {
SetStatus(database_->WriteBatch(options_, batch_));
}
}
private:
leveldb::WriteOptions options_;
leveldb::WriteBatch* batch_;
const bool hasData_;
};
/**
* Does a batch write operation on a database.
*/
NAPI_METHOD(batch_do) {
NAPI_ARGV(4);
NAPI_DB_CONTEXT();
napi_value array = argv[1];
const bool sync = BooleanProperty(env, argv[2], "sync", false);
napi_value callback = argv[3];
uint32_t length;
napi_get_array_length(env, array, &length);
leveldb::WriteBatch* batch = new leveldb::WriteBatch();
bool hasData = false;
for (uint32_t i = 0; i < length; i++) {
napi_value element;
napi_get_element(env, array, i, &element);
if (!IsObject(env, element)) continue;
std::string type = StringProperty(env, element, "type");
if (type == "del") {
if (!HasProperty(env, element, "key")) continue;
leveldb::Slice key = ToSlice(env, GetProperty(env, element, "key"));
batch->Delete(key);
if (!hasData) hasData = true;
DisposeSliceBuffer(key);
} else if (type == "put") {
if (!HasProperty(env, element, "key")) continue;
if (!HasProperty(env, element, "value")) continue;
leveldb::Slice key = ToSlice(env, GetProperty(env, element, "key"));
leveldb::Slice value = ToSlice(env, GetProperty(env, element, "value"));
batch->Put(key, value);
if (!hasData) hasData = true;
DisposeSliceBuffer(key);
DisposeSliceBuffer(value);
}
}
BatchWorker* worker = new BatchWorker(env, database, callback, batch, sync, hasData);
worker->Queue(env);
NAPI_RETURN_UNDEFINED();
}
/**
* Owns a WriteBatch.
*/
struct Batch {
Batch (Database* database)
: database_(database),
batch_(new leveldb::WriteBatch()),
hasData_(false) {}
~Batch () {
delete batch_;
}
void Put (leveldb::Slice key, leveldb::Slice value) {
batch_->Put(key, value);
hasData_ = true;
}
void Del (leveldb::Slice key) {
batch_->Delete(key);
hasData_ = true;
}
void Clear () {
batch_->Clear();
hasData_ = false;
}
leveldb::Status Write (bool sync) {
leveldb::WriteOptions options;
options.sync = sync;
return database_->WriteBatch(options, batch_);
}
Database* database_;
leveldb::WriteBatch* batch_;
bool hasData_;
};
/**
* Runs when a Batch is garbage collected.
*/
static void FinalizeBatch (napi_env env, void* data, void* hint) {
if (data) {
delete (Batch*)data;
}
}
/**
* Return a batch object.
*/
NAPI_METHOD(batch_init) {
NAPI_ARGV(1);
NAPI_DB_CONTEXT();
Batch* batch = new Batch(database);
napi_value result;
NAPI_STATUS_THROWS(napi_create_external(env, batch,
FinalizeBatch,
NULL, &result));
return result;
}
/**
* Adds a put instruction to a batch object.
*/
NAPI_METHOD(batch_put) {
NAPI_ARGV(3);
NAPI_BATCH_CONTEXT();
leveldb::Slice key = ToSlice(env, argv[1]);
leveldb::Slice value = ToSlice(env, argv[2]);
batch->Put(key, value);
DisposeSliceBuffer(key);
DisposeSliceBuffer(value);
NAPI_RETURN_UNDEFINED();
}
/**
* Adds a delete instruction to a batch object.
*/
NAPI_METHOD(batch_del) {
NAPI_ARGV(2);
NAPI_BATCH_CONTEXT();
leveldb::Slice key = ToSlice(env, argv[1]);
batch->Del(key);
DisposeSliceBuffer(key);
NAPI_RETURN_UNDEFINED();
}
/**
* Clears a batch object.
*/
NAPI_METHOD(batch_clear) {
NAPI_ARGV(1);
NAPI_BATCH_CONTEXT();
batch->Clear();
NAPI_RETURN_UNDEFINED();
}
/**
* Worker class for batch write operation.
*/
struct BatchWriteWorker final : public PriorityWorker {
BatchWriteWorker (napi_env env,
napi_value context,
Batch* batch,
napi_value callback,
const bool sync)
: PriorityWorker(env, batch->database_, callback, "leveldown.batch.write"),
batch_(batch),
sync_(sync) {
// Prevent GC of batch object before we execute
NAPI_STATUS_THROWS_VOID(napi_create_reference(env, context, 1, &contextRef_));
}
~BatchWriteWorker () {}
void DoExecute () override {
if (batch_->hasData_) {
SetStatus(batch_->Write(sync_));
}
}
void DoFinally (napi_env env) override {
napi_delete_reference(env, contextRef_);
PriorityWorker::DoFinally(env);
}
private:
Batch* batch_;
const bool sync_;
napi_ref contextRef_;
};
/**
* Writes a batch object.
*/
NAPI_METHOD(batch_write) {
NAPI_ARGV(3);
NAPI_BATCH_CONTEXT();
napi_value options = argv[1];
const bool sync = BooleanProperty(env, options, "sync", false);
napi_value callback = argv[2];
BatchWriteWorker* worker = new BatchWriteWorker(env, argv[0], batch, callback, sync);
worker->Queue(env);
NAPI_RETURN_UNDEFINED();
}
/**
* All exported functions.
*/
NAPI_INIT() {
NAPI_EXPORT_FUNCTION(db_init);
NAPI_EXPORT_FUNCTION(db_open);
NAPI_EXPORT_FUNCTION(db_close);
NAPI_EXPORT_FUNCTION(db_put);
NAPI_EXPORT_FUNCTION(db_get);
NAPI_EXPORT_FUNCTION(db_get_many);
NAPI_EXPORT_FUNCTION(db_del);
NAPI_EXPORT_FUNCTION(db_clear);
NAPI_EXPORT_FUNCTION(db_approximate_size);
NAPI_EXPORT_FUNCTION(db_compact_range);
NAPI_EXPORT_FUNCTION(db_get_property);
NAPI_EXPORT_FUNCTION(destroy_db);
NAPI_EXPORT_FUNCTION(repair_db);
NAPI_EXPORT_FUNCTION(iterator_init);
NAPI_EXPORT_FUNCTION(iterator_seek);
NAPI_EXPORT_FUNCTION(iterator_end);
NAPI_EXPORT_FUNCTION(iterator_next);
NAPI_EXPORT_FUNCTION(batch_do);
NAPI_EXPORT_FUNCTION(batch_init);
NAPI_EXPORT_FUNCTION(batch_put);
NAPI_EXPORT_FUNCTION(batch_del);
NAPI_EXPORT_FUNCTION(batch_clear);
NAPI_EXPORT_FUNCTION(batch_write);
}