/* * Copyright 2004-2006 Intel Corporation * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include #include #include #include #include #include "GlobalStore.h" #include "bundling/Bundle.h" #include "reg/APIRegistration.h" #include "routing/ProphetNode.h" namespace dtn { //---------------------------------------------------------------------- const u_int32_t GlobalStore::CURRENT_VERSION = 3; static const char* GLOBAL_TABLE = "globals"; static const char* GLOBAL_KEY = "global_key"; //---------------------------------------------------------------------- class Globals : public oasys::SerializableObject { public: Globals() {} Globals(const oasys::Builder&) {} u_int32_t version_; ///< on-disk copy of CURRENT_VERSION u_int32_t next_bundleid_; ///< running serial number for bundles u_int32_t next_regid_; ///< running serial number for registrations u_char digest_[oasys::MD5::MD5LEN]; ///< MD5 digest of all serialized fields /** * Virtual from SerializableObject. */ virtual void serialize(oasys::SerializeAction* a); }; //---------------------------------------------------------------------- void Globals::serialize(oasys::SerializeAction* a) { a->process("version", &version_); a->process("next_bundleid", &next_bundleid_); a->process("next_regid", &next_regid_); a->process("digest", digest_, 16); } //---------------------------------------------------------------------- GlobalStore* GlobalStore::instance_; //---------------------------------------------------------------------- GlobalStore::GlobalStore() : Logger("GlobalStore", "/dtn/storage/%s", GLOBAL_TABLE), globals_(NULL), store_(NULL) { lock_ = new oasys::Mutex(logpath_, oasys::Mutex::TYPE_RECURSIVE, true /* quiet */); } //---------------------------------------------------------------------- int GlobalStore::init(const oasys::StorageConfig& cfg, oasys::DurableStore* store) { if (instance_ != NULL) { PANIC("GlobalStore::init called multiple times"); } instance_ = new GlobalStore(); return instance_->do_init(cfg, store); } //---------------------------------------------------------------------- int GlobalStore::do_init(const oasys::StorageConfig& cfg, oasys::DurableStore* store) { int flags = 0; if (cfg.init_) { flags |= oasys::DS_CREATE; } int err = store->get_table(&store_, GLOBAL_TABLE, flags); if (err != 0) { log_err("error initializing global store: %s", (err == oasys::DS_NOTFOUND) ? "table not found" : "unknown error"); return err; } // if we're initializing the database for the first time, then we // prime the values accordingly and sync the database version if (cfg.init_) { log_info("initializing global table"); globals_ = new Globals(); globals_->version_ = CURRENT_VERSION; globals_->next_bundleid_ = 0; globals_->next_regid_ = Registration::MAX_RESERVED_REGID + 1; calc_digest(globals_->digest_); // store the new value err = store_->put(oasys::StringShim(GLOBAL_KEY), globals_, oasys::DS_CREATE | oasys::DS_EXCL); if (err == oasys::DS_EXISTS) { // YUCK log_err_p("/dtnd", "Initializing datastore which already exists."); exit(1); } else if (err != 0) { log_err_p("/dtnd", "unknown error initializing global store"); return err; } loaded_ = true; } else { loaded_ = false; } return 0; } //---------------------------------------------------------------------- GlobalStore::~GlobalStore() { delete store_; delete globals_; delete lock_; } //---------------------------------------------------------------------- u_int32_t GlobalStore::next_bundleid() { oasys::ScopeLock l(lock_, "GlobalStore::next_bundleid"); ASSERT(globals_->next_bundleid_ != 0xffffffff); log_debug("next_bundleid %d -> %d", globals_->next_bundleid_, globals_->next_bundleid_ + 1); u_int32_t ret = globals_->next_bundleid_++; update(); return ret; } //---------------------------------------------------------------------- u_int32_t GlobalStore::next_regid() { oasys::ScopeLock l(lock_, "GlobalStore::next_regid"); ASSERT(globals_->next_regid_ != 0xffffffff); log_debug("next_regid %d -> %d", globals_->next_regid_, globals_->next_regid_ + 1); u_int32_t ret = globals_->next_regid_++; update(); return ret; } //---------------------------------------------------------------------- void GlobalStore::calc_digest(u_char* digest) { // we create a dummy Bundle and a Registration (and in the future // a link), then take their serialized form and MD5 it, such that // adding or deleting a field will change the digest Bundle b(oasys::Builder::builder()); APIRegistration r(oasys::Builder::builder()); ProphetNode n(oasys::Builder::builder()); oasys::StringSerialize s(oasys::Serialize::CONTEXT_LOCAL, oasys::StringSerialize::INCLUDE_NAME | oasys::StringSerialize::INCLUDE_TYPE | oasys::StringSerialize::SCHEMA_ONLY); s.action(&b); s.action(&r); s.action(&n); oasys::MD5 md5; md5.update(s.buf().data(), s.buf().length()); md5.finalize(); log_debug("calculated digest %s for serialize string '%s'", md5.digest_ascii().c_str(), s.buf().c_str()); memcpy(digest, md5.digest(), oasys::MD5::MD5LEN); } //---------------------------------------------------------------------- bool GlobalStore::load() { log_debug("loading global store"); oasys::StringShim key(GLOBAL_KEY); if (globals_ != NULL) { delete globals_; globals_ = NULL; } if (store_->get(key, &globals_) != 0) { log_crit("error loading global data"); return false; } ASSERT(globals_ != NULL); if (globals_->version_ != CURRENT_VERSION) { log_crit("datastore version mismatch: " "expected version %d, database version %d", CURRENT_VERSION, globals_->version_); return false; } u_char digest[oasys::MD5::MD5LEN]; calc_digest(digest); if (memcmp(digest, globals_->digest_, oasys::MD5::MD5LEN) != 0) { log_crit("datastore digest mismatch: " "expected %s, database contains %s", oasys::hex2str(digest, oasys::MD5::MD5LEN).c_str(), oasys::hex2str(globals_->digest_, oasys::MD5::MD5LEN).c_str()); log_crit("(implies serialized schema change)"); return false; } loaded_ = true; return true; } //---------------------------------------------------------------------- void GlobalStore::update() { ASSERT(lock_->is_locked_by_me()); log_debug("updating global store"); // make certain we don't attempt to write out globals before // load() has had a chance to load them from the database ASSERT(loaded_); int err = store_->put(oasys::StringShim(GLOBAL_KEY), globals_, 0); if (err != 0) { PANIC("GlobalStore::update fatal error updating database: %s", oasys::durable_strerror(err)); } } //---------------------------------------------------------------------- void GlobalStore::close() { // we prevent the potential for shutdown race crashes by leaving // the global store locked after it's been closed so other threads // will simply block, not crash due to a null store lock_->lock("GlobalStore::close"); delete store_; store_ = NULL; delete instance_; instance_ = NULL; } } // namespace dtn