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//
// Copyright Aliaksei Levin (levlam@telegram.org), Arseny Smirnov (arseny30@gmail.com) 2014-2026
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//
#pragma once
#include "td/db/SqliteDb.h"
#include "td/db/SqliteStatement.h"
#include "td/utils/common.h"
#include "td/utils/FlatHashMap.h"
#include "td/utils/Slice.h"
#include "td/utils/SliceBuilder.h"
#include "td/utils/Status.h"
namespace td {
class SqliteKeyValue {
public:
static Status drop(SqliteDb &connection, Slice table_name) TD_WARN_UNUSED_RESULT {
return connection.exec(PSLICE() << "DROP TABLE IF EXISTS " << table_name);
}
static Status init(SqliteDb &connection, Slice table_name) TD_WARN_UNUSED_RESULT {
return connection.exec(PSLICE() << "CREATE TABLE IF NOT EXISTS " << table_name << " (k BLOB PRIMARY KEY, v BLOB)");
}
bool empty() const {
return db_.empty();
}
Status init_with_connection(SqliteDb connection, string table_name) TD_WARN_UNUSED_RESULT;
void close() {
*this = SqliteKeyValue();
}
Status drop();
void set(Slice key, Slice value);
void set_all(const FlatHashMap<string, string> &key_values);
string get(Slice key);
void erase(Slice key);
void erase_batch(vector<string> keys);
Status begin_read_transaction() TD_WARN_UNUSED_RESULT {
return db_.begin_read_transaction();
}
Status begin_write_transaction() TD_WARN_UNUSED_RESULT {
return db_.begin_write_transaction();
}
Status commit_transaction() TD_WARN_UNUSED_RESULT {
return db_.commit_transaction();
}
void erase_by_prefix(Slice prefix);
FlatHashMap<string, string> get_all() {
FlatHashMap<string, string> res;
get_by_prefix("", [&](Slice key, Slice value) {
CHECK(!key.empty());
res.emplace(key.str(), value.str());
return true;
});
return res;
}
template <class CallbackT>
void get_by_prefix(Slice prefix, CallbackT &&callback) {
string next;
if (!prefix.empty()) {
next = next_prefix(prefix);
}
get_by_range_impl(prefix, next, true, callback);
}
template <class CallbackT>
void get_by_range(Slice from, Slice till, CallbackT &&callback) {
get_by_range_impl(from, till, false, std::move(callback));
}
private:
template <class CallbackT>
void get_by_range_impl(Slice from, Slice till, bool strip_key_prefix, CallbackT &&callback) {
SqliteStatement *stmt = nullptr;
if (from.empty()) {
stmt = &get_all_stmt_;
} else {
if (till.empty()) {
stmt = &get_by_prefix_rare_stmt_;
stmt->bind_blob(1, till).ensure();
} else {
stmt = &get_by_prefix_stmt_;
stmt->bind_blob(1, from).ensure();
stmt->bind_blob(2, till).ensure();
}
}
auto guard = stmt->guard();
stmt->step().ensure();
while (stmt->has_row()) {
auto key = stmt->view_blob(0);
if (strip_key_prefix) {
key.remove_prefix(from.size());
}
if (!callback(key, stmt->view_blob(1))) {
return;
}
stmt->step().ensure();
}
}
string table_name_;
SqliteDb db_;
SqliteStatement get_stmt_;
SqliteStatement set_stmt_;
SqliteStatement erase_stmt_;
SqliteStatement get_all_stmt_;
SqliteStatement erase_by_prefix_stmt_;
SqliteStatement erase_by_prefix_rare_stmt_;
SqliteStatement get_by_prefix_stmt_;
SqliteStatement get_by_prefix_rare_stmt_;
static string next_prefix(Slice prefix);
};
} // namespace td
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