+++ /dev/null
-// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
-// vim: ts=8 sw=2 smarttab
-#include "include/encoding.h"
-#include "KeyValueDBMemory.h"
-#include <map>
-#include <set>
-#include "include/memory.h"
-#include <iostream>
-
-using namespace std;
-
-/**
- * Iterate over the whole key space of the in-memory store
- *
- * @note Removing keys from the store while iterating over the store key-space
- * may result in unspecified behavior.
- * If one wants to safely iterate over the store while updating the
- * store, one should instead use a snapshot iterator, which provides
- * strong read-consistency.
- */
-class WholeSpaceMemIterator : public KeyValueDB::WholeSpaceIteratorImpl {
-protected:
- KeyValueDBMemory *db;
- bool ready;
-
- map<pair<string,string>, bufferlist>::iterator it;
-
-public:
- explicit WholeSpaceMemIterator(KeyValueDBMemory *db) : db(db), ready(false) { }
- ~WholeSpaceMemIterator() override { }
-
- int seek_to_first() override {
- if (db->db.empty()) {
- it = db->db.end();
- ready = false;
- return 0;
- }
- it = db->db.begin();
- ready = true;
- return 0;
- }
-
- int seek_to_first(const string &prefix) override {
- it = db->db.lower_bound(make_pair(prefix, ""));
- if (db->db.empty() || (it == db->db.end())) {
- it = db->db.end();
- ready = false;
- return 0;
- }
- ready = true;
- return 0;
- }
-
- int seek_to_last() override {
- it = db->db.end();
- if (db->db.empty()) {
- ready = false;
- return 0;
- }
- --it;
- assert(it != db->db.end());
- ready = true;
- return 0;
- }
-
- int seek_to_last(const string &prefix) override {
- string tmp(prefix);
- tmp.append(1, (char) 0);
- it = db->db.upper_bound(make_pair(tmp,""));
-
- if (db->db.empty() || (it == db->db.end())) {
- seek_to_last();
- }
- else {
- ready = true;
- prev();
- }
- return 0;
- }
-
- int lower_bound(const string &prefix, const string &to) override {
- it = db->db.lower_bound(make_pair(prefix,to));
- if ((db->db.empty()) || (it == db->db.end())) {
- it = db->db.end();
- ready = false;
- return 0;
- }
-
- assert(it != db->db.end());
-
- ready = true;
- return 0;
- }
-
- int upper_bound(const string &prefix, const string &after) override {
- it = db->db.upper_bound(make_pair(prefix,after));
- if ((db->db.empty()) || (it == db->db.end())) {
- it = db->db.end();
- ready = false;
- return 0;
- }
- assert(it != db->db.end());
- ready = true;
- return 0;
- }
-
- bool valid() override {
- return ready && (it != db->db.end());
- }
-
- bool begin() {
- return ready && (it == db->db.begin());
- }
-
- int prev() override {
- if (!begin() && ready)
- --it;
- else
- it = db->db.end();
- return 0;
- }
-
- int next() override {
- if (valid())
- ++it;
- return 0;
- }
-
- string key() override {
- if (valid())
- return (*it).first.second;
- else
- return "";
- }
-
- pair<string,string> raw_key() override {
- if (valid())
- return (*it).first;
- else
- return make_pair("", "");
- }
-
- bool raw_key_is_prefixed(const string &prefix) override {
- return prefix == (*it).first.first;
- }
-
- bufferlist value() override {
- if (valid())
- return (*it).second;
- else
- return bufferlist();
- }
-
- int status() override {
- return 0;
- }
-};
-
-int KeyValueDBMemory::get(const string &prefix,
- const std::set<string> &key,
- map<string, bufferlist> *out) {
- if (!exists_prefix(prefix))
- return 0;
-
- for (std::set<string>::const_iterator i = key.begin();
- i != key.end();
- ++i) {
- pair<string,string> k(prefix, *i);
- if (db.count(k))
- (*out)[*i] = db[k];
- }
- return 0;
-}
-
-int KeyValueDBMemory::get_keys(const string &prefix,
- const std::set<string> &key,
- std::set<string> *out) {
- if (!exists_prefix(prefix))
- return 0;
-
- for (std::set<string>::const_iterator i = key.begin();
- i != key.end();
- ++i) {
- if (db.count(make_pair(prefix, *i)))
- out->insert(*i);
- }
- return 0;
-}
-
-int KeyValueDBMemory::set(const string &prefix,
- const string &key,
- const bufferlist &bl) {
- db[make_pair(prefix,key)] = bl;
- return 0;
-}
-
-int KeyValueDBMemory::rmkey(const string &prefix,
- const string &key) {
- db.erase(make_pair(prefix,key));
- return 0;
-}
-
-int KeyValueDBMemory::rmkeys_by_prefix(const string &prefix) {
- map<std::pair<string,string>,bufferlist>::iterator i;
- i = db.lower_bound(make_pair(prefix, ""));
- if (i == db.end())
- return 0;
-
- while (i != db.end()) {
- std::pair<string,string> key = (*i).first;
- if (key.first != prefix)
- break;
-
- ++i;
- rmkey(key.first, key.second);
- }
- return 0;
-}
-
-int KeyValueDBMemory::rm_range_keys(const string &prefix, const string &start, const string &end) {
- map<std::pair<string,string>,bufferlist>::iterator i;
- i = db.lower_bound(make_pair(prefix, start));
- if (i == db.end())
- return 0;
-
- while (i != db.end()) {
- std::pair<string,string> key = (*i).first;
- if (key.first != prefix)
- break;
- if (key.second >= end)
- break;
- ++i;
- rmkey(key.first, key.second);
- }
- return 0;
-}
-
-KeyValueDB::WholeSpaceIterator KeyValueDBMemory::_get_iterator() {
- return ceph::shared_ptr<KeyValueDB::WholeSpaceIteratorImpl>(
- new WholeSpaceMemIterator(this)
- );
-}
-
-class WholeSpaceSnapshotMemIterator : public WholeSpaceMemIterator {
-public:
-
- /**
- * @note
- * We perform a copy of the db map, which is populated by bufferlists.
- *
- * These are designed as shallow containers, thus there is a chance that
- * changing the underlying memory pages will lead to the iterator seeing
- * erroneous states.
- *
- * Although we haven't verified this yet, there is this chance, so we should
- * keep it in mind.
- */
-
- explicit WholeSpaceSnapshotMemIterator(KeyValueDBMemory *db) :
- WholeSpaceMemIterator(db) { }
- ~WholeSpaceSnapshotMemIterator() override {
- delete db;
- }
-};
-
Code Review / stor4nfv.git / blobdiff