diff --git a/apple/external_commit_helper.cpp b/apple/external_commit_helper.cpp new file mode 100644 index 00000000..1444281a --- /dev/null +++ b/apple/external_commit_helper.cpp @@ -0,0 +1,250 @@ +//////////////////////////////////////////////////////////////////////////// +// +// Copyright 2015 Realm Inc. +// +// 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 "external_commit_helper.hpp" + +#include "shared_realm.hpp" + +#include +#include +#include +#include +#include +#include +#include +#include + +using namespace realm; + +namespace { +// Write a byte to a pipe to notify anyone waiting for data on the pipe +void notify_fd(int fd) +{ + while (true) { + char c = 0; + ssize_t ret = write(fd, &c, 1); + if (ret == 1) { + break; + } + + // If the pipe's buffer is full, we need to read some of the old data in + // it to make space. We don't just read in the code waiting for + // notifications so that we can notify multiple waiters with a single + // write. + assert(ret == -1 && errno == EAGAIN); + char buff[1024]; + read(fd, buff, sizeof buff); + } +} +} // anonymous namespace + +void ExternalCommitHelper::FdHolder::close() +{ + if (m_fd != -1) { + ::close(m_fd); + } + m_fd = -1; + +} + +// Inter-thread and inter-process notifications of changes are done using a +// named pipe in the filesystem next to the Realm file. Everyone who wants to be +// notified of commits waits for data to become available on the pipe, and anyone +// who commits a write transaction writes data to the pipe after releasing the +// write lock. Note that no one ever actually *reads* from the pipe: the data +// actually written is meaningless, and trying to read from a pipe from multiple +// processes at once is fraught with race conditions. + +// When a RLMRealm instance is created, we add a CFRunLoopSource to the current +// thread's runloop. On each cycle of the run loop, the run loop checks each of +// its sources for work to do, which in the case of CFRunLoopSource is just +// checking if CFRunLoopSourceSignal has been called since the last time it ran, +// and if so invokes the function pointer supplied when the source is created, +// which in our case just invokes `[realm handleExternalChange]`. + +// Listening for external changes is done using kqueue() on a background thread. +// kqueue() lets us efficiently wait until the amount of data which can be read +// from one or more file descriptors has changed, and tells us which of the file +// descriptors it was that changed. We use this to wait on both the shared named +// pipe, and a local anonymous pipe. When data is written to the named pipe, we +// signal the runloop source and wake up the target runloop, and when data is +// written to the anonymous pipe the background thread removes the runloop +// source from the runloop and and shuts down. +ExternalCommitHelper::ExternalCommitHelper(Realm* realm) +{ + add_realm(realm); + + m_kq = kqueue(); + if (m_kq == -1) { + throw std::system_error(errno, std::system_category()); + } + + auto path = realm->config().path + ".note"; + + // Create and open the named pipe + int ret = mkfifo(path.c_str(), 0600); + if (ret == -1) { + int err = errno; + if (err == ENOTSUP) { + // Filesystem doesn't support named pipes, so try putting it in tmp instead + // Hash collisions are okay here because they just result in doing + // extra work, as opposed to correctness problems + std::ostringstream ss; + ss << getenv("TMPDIR"); + ss << "realm_" << std::hash()(path) << ".note"; + path = ss.str(); + ret = mkfifo(path.c_str(), 0600); + err = errno; + } + // the fifo already existing isn't an error + if (ret == -1 && err != EEXIST) { + throw std::system_error(err, std::system_category()); + } + } + + m_notify_fd = open(path.c_str(), O_RDWR); + if (m_notify_fd == -1) { + throw std::system_error(errno, std::system_category()); + } + + // Make writing to the pipe return -1 when the pipe's buffer is full + // rather than blocking until there's space available + ret = fcntl(m_notify_fd, F_SETFL, O_NONBLOCK); + if (ret == -1) { + throw std::system_error(errno, std::system_category()); + } + + // Create the anonymous pipe + int pipeFd[2]; + ret = pipe(pipeFd); + if (ret == -1) { + throw std::system_error(errno, std::system_category()); + } + + m_shutdown_read_fd = pipeFd[0]; + m_shutdown_write_fd = pipeFd[1]; + + // Use the minimum allowed stack size, as we need very little in our listener + // https://developer.apple.com/library/ios/documentation/Cocoa/Conceptual/Multithreading/CreatingThreads/CreatingThreads.html#//apple_ref/doc/uid/10000057i-CH15-SW7 + pthread_attr_t attr; + pthread_attr_init(&attr); + pthread_attr_setstacksize(&attr, 16 * 1024); + + auto fn = [](void *self) -> void * { + static_cast(self)->listen(); + return nullptr; + }; + ret = pthread_create(&m_thread, &attr, fn, this); + pthread_attr_destroy(&attr); + if (ret != 0) { + throw std::system_error(errno, std::system_category()); + } +} + +ExternalCommitHelper::~ExternalCommitHelper() +{ + REALM_ASSERT_DEBUG(m_realms.empty()); + notify_fd(m_shutdown_write_fd); + pthread_join(m_thread, nullptr); // Wait for the thread to exit +} + +void ExternalCommitHelper::add_realm(realm::Realm* realm) +{ + std::lock_guard lock(m_realms_mutex); + + // Create the runloop source + CFRunLoopSourceContext ctx{}; + ctx.info = realm; + ctx.perform = [](void* info) { + static_cast(info)->notify(); + }; + + CFRunLoopRef runloop = CFRunLoopGetCurrent(); + CFRetain(runloop); + CFRunLoopSourceRef signal = CFRunLoopSourceCreate(kCFAllocatorDefault, 0, &ctx); + CFRunLoopAddSource(runloop, signal, kCFRunLoopDefaultMode); + + m_realms.push_back({realm, runloop, signal}); +} + +void ExternalCommitHelper::remove_realm(realm::Realm* realm) +{ + std::lock_guard lock(m_realms_mutex); + for (auto it = m_realms.begin(); it != m_realms.end(); ++it) { + if (it->realm == realm) { + CFRunLoopSourceInvalidate(it->signal); + CFRelease(it->signal); + CFRelease(it->runloop); + m_realms.erase(it); + return; + } + } + REALM_TERMINATE("Realm not registered"); +} + +void ExternalCommitHelper::listen() +{ + pthread_setname_np("RLMRealm notification listener"); + + + // Set up the kqueue + // EVFILT_READ indicates that we care about data being available to read + // on the given file descriptor. + // EV_CLEAR makes it wait for the amount of data available to be read to + // change rather than just returning when there is any data to read. + struct kevent ke[2]; + EV_SET(&ke[0], m_notify_fd, EVFILT_READ, EV_ADD | EV_CLEAR, 0, 0, 0); + EV_SET(&ke[1], m_shutdown_read_fd, EVFILT_READ, EV_ADD | EV_CLEAR, 0, 0, 0); + int ret = kevent(m_kq, ke, 2, nullptr, 0, nullptr); + assert(ret == 0); + + while (true) { + struct kevent event; + // Wait for data to become on either fd + // Return code is number of bytes available or -1 on error + ret = kevent(m_kq, nullptr, 0, &event, 1, nullptr); + assert(ret >= 0); + if (ret == 0) { + // Spurious wakeup; just wait again + continue; + } + + // Check which file descriptor had activity: if it's the shutdown + // pipe, then someone called -stop; otherwise it's the named pipe + // and someone committed a write transaction + if (event.ident == (uint32_t)m_shutdown_read_fd) { + return; + } + assert(event.ident == (uint32_t)m_notify_fd); + + std::lock_guard lock(m_realms_mutex); + for (auto const& realm : m_realms) { + CFRunLoopSourceSignal(realm.signal); + // Signalling the source makes it run the next time the runloop gets + // to it, but doesn't make the runloop start if it's currently idle + // waiting for events + CFRunLoopWakeUp(realm.runloop); + } + } +} + +void ExternalCommitHelper::notify_others() +{ + notify_fd(m_notify_fd); +} + diff --git a/apple/external_commit_helper.hpp b/apple/external_commit_helper.hpp new file mode 100644 index 00000000..acf0e1c4 --- /dev/null +++ b/apple/external_commit_helper.hpp @@ -0,0 +1,92 @@ +//////////////////////////////////////////////////////////////////////////// +// +// Copyright 2015 Realm Inc. +// +// 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. +// +//////////////////////////////////////////////////////////////////////////// + +#ifndef REALM_EXTERNAL_COMMIT_HELPER_HPP +#define REALM_EXTERNAL_COMMIT_HELPER_HPP + +#include +#include +#include + +namespace realm { +class Realm; + +class ExternalCommitHelper { +public: + ExternalCommitHelper(Realm* realm); + ~ExternalCommitHelper(); + + void notify_others(); + void add_realm(Realm* realm); + void remove_realm(Realm* realm); + +private: + // A RAII holder for a file descriptor which automatically closes the wrapped + // fd when it's deallocated + class FdHolder { + public: + FdHolder() = default; + ~FdHolder() { close(); } + operator int() const { return m_fd; } + + FdHolder& operator=(int newFd) { + close(); + m_fd = newFd; + return *this; + } + + private: + int m_fd = -1; + void close(); + + FdHolder& operator=(FdHolder const&) = delete; + FdHolder(FdHolder const&) = delete; + }; + + struct PerRealmInfo { + Realm* realm; + CFRunLoopRef runloop; + CFRunLoopSourceRef signal; + }; + + void listen(); + + // Currently registered realms and the signal for delivering notifications + // to them + std::vector m_realms; + + // Mutex which guards m_realms + std::mutex m_realms_mutex; + + // The listener thread + pthread_t m_thread; + + // Read-write file descriptor for the named pipe which is waited on for + // changes and written to when a commit is made + FdHolder m_notify_fd; + // File descriptor for the kqueue + FdHolder m_kq; + // The two ends of an anonymous pipe used to notify the kqueue() thread that + // it should be shut down. + FdHolder m_shutdown_read_fd; + FdHolder m_shutdown_write_fd; +}; + +} // namespace realm + +#endif /* REALM_EXTERNAL_COMMIT_HELPER_HPP */ diff --git a/index_set.cpp b/index_set.cpp new file mode 100644 index 00000000..b7e4961c --- /dev/null +++ b/index_set.cpp @@ -0,0 +1,92 @@ +//////////////////////////////////////////////////////////////////////////// +// +// Copyright 2015 Realm Inc. +// +// 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 "index_set.hpp" + +using namespace realm; + +IndexSet::iterator IndexSet::find(size_t index) +{ + for (auto it = m_ranges.begin(), end = m_ranges.end(); it != end; ++it) { + if (it->second > index) + return it; + } + return m_ranges.end(); +} + +void IndexSet::add(size_t index) +{ + do_add(find(index), index); +} + +void IndexSet::do_add(iterator it, size_t index) +{ + bool more_before = it != m_ranges.begin(), valid = it != m_ranges.end(); + if (valid && it->first <= index && it->second > index) { + // index is already in set + } + else if (more_before && (it - 1)->second == index) { + // index is immediately after an existing range + ++(it - 1)->second; + } + else if (more_before && valid && (it - 1)->second == it->first) { + // index joins two existing ranges + (it - 1)->second = it->second; + m_ranges.erase(it); + } + else if (valid && it->first == index + 1) { + // index is immediately before an existing range + --it->first; + } + else { + // index is not next to an existing range + m_ranges.insert(it, {index, index + 1}); + } +} + +void IndexSet::set(size_t len) +{ + m_ranges.clear(); + if (len) { + m_ranges.push_back({0, len}); + } +} + +void IndexSet::insert_at(size_t index) +{ + auto pos = find(index); + if (pos != m_ranges.end()) { + if (pos->first >= index) + ++pos->first; + ++pos->second; + for (auto it = pos + 1; it != m_ranges.end(); ++it) { + ++it->first; + ++it->second; + } + } + do_add(pos, index); +} + +void IndexSet::add_shifted(size_t index) +{ + auto it = m_ranges.begin(); + for (auto end = m_ranges.end(); it != end && it->first <= index; ++it) { + index += it->second - it->first; + } + do_add(it, index); +} diff --git a/index_set.hpp b/index_set.hpp new file mode 100644 index 00000000..7a229177 --- /dev/null +++ b/index_set.hpp @@ -0,0 +1,62 @@ +//////////////////////////////////////////////////////////////////////////// +// +// Copyright 2015 Realm Inc. +// +// 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. +// +//////////////////////////////////////////////////////////////////////////// + +#ifndef REALM_INDEX_SET_HPP +#define REALM_INDEX_SET_HPP + +#include + +namespace realm { +class IndexSet { +public: + using value_type = std::pair; + using iterator = std::vector::iterator; + using const_iterator = std::vector::const_iterator; + + const_iterator begin() const { return m_ranges.begin(); } + const_iterator end() const { return m_ranges.end(); } + bool empty() const { return m_ranges.empty(); } + size_t size() const { return m_ranges.size(); } + + // Add an index to the set, doing nothing if it's already present + void add(size_t index); + + // Remove all indexes from the set and then add a single range starting from + // zero with the given length + void set(size_t len); + + // Insert an index at the given position, shifting existing indexes at or + // after that point back by one + void insert_at(size_t index); + + // Add an index which has had all of the ranges in the set before it removed + void add_shifted(size_t index); + +private: + std::vector m_ranges; + + // Find the range which contains the index, or the first one after it if + // none do + iterator find(size_t index); + // Insert the index before the given position, combining existing ranges as + // applicable + void do_add(iterator pos, size_t index); +}; +} // namespace realm + +#endif // REALM_INDEX_SET_HPP diff --git a/object_schema.cpp b/object_schema.cpp index 83edd1f1..33cd2497 100644 --- a/object_schema.cpp +++ b/object_schema.cpp @@ -17,16 +17,19 @@ //////////////////////////////////////////////////////////////////////////// #include "object_schema.hpp" + #include "object_store.hpp" +#include "property.hpp" #include #include using namespace realm; -ObjectSchema::ObjectSchema(Group *group, const std::string &name) : name(name) { - TableRef tableRef = ObjectStore::table_for_object_type(group, name); - Table *table = tableRef.get(); +ObjectSchema::~ObjectSchema() = default; + +ObjectSchema::ObjectSchema(const Group *group, const std::string &name) : name(name) { + ConstTableRef table = ObjectStore::table_for_object_type(group, name); size_t count = table->get_column_count(); properties.reserve(count); @@ -40,7 +43,7 @@ ObjectSchema::ObjectSchema(Group *group, const std::string &name) : name(name) { property.table_column = col; if (property.type == PropertyTypeObject || property.type == PropertyTypeArray) { // set link type for objects and arrays - realm::TableRef linkTable = table->get_link_target(col); + ConstTableRef linkTable = table->get_link_target(col); property.object_type = ObjectStore::object_type_for_table_name(linkTable->get_name().data()); } properties.push_back(std::move(property)); @@ -56,12 +59,15 @@ ObjectSchema::ObjectSchema(Group *group, const std::string &name) : name(name) { } } -Property *ObjectSchema::property_for_name(const std::string &name) { - for (auto& prop:properties) { - if (prop.name == name) { +Property *ObjectSchema::property_for_name(StringData name) { + for (auto& prop : properties) { + if (StringData(prop.name) == name) { return ∝ } } return nullptr; } +const Property *ObjectSchema::property_for_name(StringData name) const { + return const_cast(this)->property_for_name(name); +} diff --git a/object_schema.hpp b/object_schema.hpp index 56a14d17..aca4af31 100644 --- a/object_schema.hpp +++ b/object_schema.hpp @@ -19,30 +19,36 @@ #ifndef REALM_OBJECT_SCHEMA_HPP #define REALM_OBJECT_SCHEMA_HPP +#include + #include #include -#include "property.hpp" - namespace realm { + class Property; class Group; class ObjectSchema { public: - ObjectSchema() {} + ObjectSchema() = default; + ~ObjectSchema(); // create object schema from existing table // if no table is provided it is looked up in the group - ObjectSchema(Group *group, const std::string &name); + ObjectSchema(const Group *group, const std::string &name); std::string name; std::vector properties; std::string primary_key; - Property *property_for_name(const std::string &name); + Property *property_for_name(StringData name); + const Property *property_for_name(StringData name) const; Property *primary_key_property() { return property_for_name(primary_key); } + const Property *primary_key_property() const { + return property_for_name(primary_key); + } }; } diff --git a/object_store.cpp b/object_store.cpp index 3d1ec9c3..035ce4fc 100644 --- a/object_store.cpp +++ b/object_store.cpp @@ -18,9 +18,11 @@ #include "object_store.hpp" +#include "schema.hpp" + #include -#include #include +#include #include #include @@ -45,7 +47,7 @@ const size_t c_object_table_prefix_length = c_object_table_prefix.length(); const uint64_t ObjectStore::NotVersioned = std::numeric_limits::max(); -bool ObjectStore::has_metadata_tables(Group *group) { +bool ObjectStore::has_metadata_tables(const Group *group) { return group->get_table(c_primaryKeyTableName) && group->get_table(c_metadataTableName); } @@ -71,8 +73,8 @@ bool ObjectStore::create_metadata_tables(Group *group) { return changed; } -uint64_t ObjectStore::get_schema_version(Group *group) { - TableRef table = group->get_table(c_metadataTableName); +uint64_t ObjectStore::get_schema_version(const Group *group) { + ConstTableRef table = group->get_table(c_metadataTableName); if (!table || table->get_column_count() == 0) { return ObjectStore::NotVersioned; } @@ -84,8 +86,8 @@ void ObjectStore::set_schema_version(Group *group, uint64_t version) { table->set_int(c_versionColumnIndex, c_zeroRowIndex, version); } -StringData ObjectStore::get_primary_key_for_object(Group *group, StringData object_type) { - TableRef table = group->get_table(c_primaryKeyTableName); +StringData ObjectStore::get_primary_key_for_object(const Group *group, StringData object_type) { + ConstTableRef table = group->get_table(c_primaryKeyTableName); if (!table) { return ""; } @@ -132,26 +134,34 @@ TableRef ObjectStore::table_for_object_type(Group *group, StringData object_type return group->get_table(table_name_for_object_type(object_type)); } +ConstTableRef ObjectStore::table_for_object_type(const Group *group, StringData object_type) { + return group->get_table(table_name_for_object_type(object_type)); +} + TableRef ObjectStore::table_for_object_type_create_if_needed(Group *group, const StringData &object_type, bool &created) { return group->get_or_add_table(table_name_for_object_type(object_type), &created); } -static inline bool property_has_changed(Property &p1, Property &p2) { - return p1.type != p2.type || p1.name != p2.name || p1.object_type != p2.object_type || p1.is_nullable != p2.is_nullable; +static inline bool property_has_changed(Property const& p1, Property const& p2) { + return p1.type != p2.type + || p1.name != p2.name + || p1.object_type != p2.object_type + || p1.is_nullable != p2.is_nullable; } -void ObjectStore::verify_schema(Group *group, Schema &target_schema, bool allow_missing_tables) { +void ObjectStore::verify_schema(Schema const& actual_schema, Schema& target_schema, bool allow_missing_tables) { std::vector errors; for (auto &object_schema : target_schema) { - if (!table_for_object_type(group, object_schema.first)) { + auto matching_schema = actual_schema.find(object_schema); + if (matching_schema == actual_schema.end()) { if (!allow_missing_tables) { - errors.emplace_back(ObjectSchemaValidationException(object_schema.first, - "Missing table for object type '" + object_schema.first + "'.")); + errors.emplace_back(ObjectSchemaValidationException(object_schema.name, + "Missing table for object type '" + object_schema.name + "'.")); } continue; } - auto more_errors = verify_object_schema(group, object_schema.second, target_schema); + auto more_errors = verify_object_schema(*matching_schema, object_schema); errors.insert(errors.end(), more_errors.begin(), more_errors.end()); } if (errors.size()) { @@ -159,12 +169,11 @@ void ObjectStore::verify_schema(Group *group, Schema &target_schema, bool allow_ } } -std::vector ObjectStore::verify_object_schema(Group *group, ObjectSchema &target_schema, Schema &schema) { +std::vector ObjectStore::verify_object_schema(ObjectSchema const& table_schema, + ObjectSchema& target_schema) { std::vector exceptions; - ObjectSchema table_schema(group, target_schema.name); // check to see if properties are the same - Property *primary = nullptr; for (auto& current_prop : table_schema.properties) { auto target_prop = target_schema.property_for_name(current_prop.name); @@ -177,38 +186,6 @@ std::vector ObjectStore::verify_object_schema(G continue; } - // check object_type existence - if (current_prop.object_type.length() && schema.find(current_prop.object_type) == schema.end()) { - exceptions.emplace_back(MissingObjectTypeException(table_schema.name, current_prop)); - } - - // check nullablity - if (current_prop.type == PropertyTypeObject) { - if (!current_prop.is_nullable) { - exceptions.emplace_back(InvalidNullabilityException(table_schema.name, current_prop)); - } - } - else { - if (current_prop.is_nullable) { - exceptions.emplace_back(InvalidNullabilityException(table_schema.name, current_prop)); - } - } - - // check primary keys - if (current_prop.is_primary) { - if (primary) { - exceptions.emplace_back(DuplicatePrimaryKeysException(table_schema.name)); - } - primary = ¤t_prop; - } - - // check indexable - if (current_prop.is_indexed) { - if (current_prop.type != PropertyTypeString && current_prop.type != PropertyTypeInt) { - exceptions.emplace_back(PropertyTypeNotIndexableException(table_schema.name, current_prop)); - } - } - // create new property with aligned column target_prop->table_column = current_prop.table_column; } @@ -228,17 +205,6 @@ std::vector ObjectStore::verify_object_schema(G return exceptions; } -void ObjectStore::update_column_mapping(Group *group, ObjectSchema &target_schema) { - ObjectSchema table_schema(group, target_schema.name); - for (auto& target_prop : target_schema.properties) { - auto table_prop = table_schema.property_for_name(target_prop.name); - if (table_prop) { - // Update target property column to match what's in the realm if it exists - target_prop.table_column = table_prop->table_column; - } - } -} - // set references to tables on targetSchema and create/update any missing or out-of-date tables // if update existing is true, updates existing tables, otherwise validates existing tables // NOTE: must be called from within write transaction @@ -249,11 +215,11 @@ bool ObjectStore::create_tables(Group *group, Schema &target_schema, bool update std::vector to_update; for (auto& object_schema : target_schema) { bool created = false; - ObjectStore::table_for_object_type_create_if_needed(group, object_schema.first, created); + ObjectStore::table_for_object_type_create_if_needed(group, object_schema.name, created); // we will modify tables for any new objectSchema (table was created) or for all if update_existing is true if (update_existing || created) { - to_update.push_back(&object_schema.second); + to_update.push_back(&object_schema); changed = true; } } @@ -264,12 +230,26 @@ bool ObjectStore::create_tables(Group *group, Schema &target_schema, bool update ObjectSchema current_schema(group, target_object_schema->name); std::vector &target_props = target_object_schema->properties; + // remove extra columns + size_t deleted = 0; + for (auto& current_prop : current_schema.properties) { + current_prop.table_column -= deleted; + + auto target_prop = target_object_schema->property_for_name(current_prop.name); + if (!target_prop || property_has_changed(current_prop, *target_prop)) { + table->remove_column(current_prop.table_column); + ++deleted; + current_prop.table_column = npos; + changed = true; + } + } + // add missing columns for (auto& target_prop : target_props) { auto current_prop = current_schema.property_for_name(target_prop.name); - // add any new properties (new name or different type) - if (!current_prop || property_has_changed(*current_prop, target_prop)) { + // add any new properties (no old column or old column was removed due to not matching) + if (!current_prop || current_prop->table_column == npos) { switch (target_prop.type) { // for objects and arrays, we have to specify target table case PropertyTypeObject: @@ -279,23 +259,16 @@ bool ObjectStore::create_tables(Group *group, Schema &target_schema, bool update break; } default: - target_prop.table_column = table->add_column(DataType(target_prop.type), target_prop.name); + target_prop.table_column = table->add_column(DataType(target_prop.type), + target_prop.name, + target_prop.is_nullable); break; } changed = true; } - } - - // remove extra columns - sort(begin(current_schema.properties), end(current_schema.properties), [](Property &i, Property &j) { - return j.table_column < i.table_column; - }); - for (auto& current_prop : current_schema.properties) { - auto target_prop = target_object_schema->property_for_name(current_prop.name); - if (!target_prop || property_has_changed(current_prop, *target_prop)) { - table->remove_column(current_prop.table_column); - changed = true; + else { + target_prop.table_column = current_prop->table_column; } } @@ -316,7 +289,7 @@ bool ObjectStore::create_tables(Group *group, Schema &target_schema, bool update return changed; } -bool ObjectStore::is_schema_at_version(Group *group, uint64_t version) { +bool ObjectStore::is_schema_at_version(const Group *group, uint64_t version) { uint64_t old_version = get_schema_version(group); if (old_version > version && old_version != NotVersioned) { throw InvalidSchemaVersionException(old_version, version); @@ -324,25 +297,32 @@ bool ObjectStore::is_schema_at_version(Group *group, uint64_t version) { return old_version == version; } -bool ObjectStore::realm_requires_update(Group *group, uint64_t version, Schema &schema) { - if (!is_schema_at_version(group, version)) { - return true; - } - for (auto& target_schema : schema) { - TableRef table = table_for_object_type(group, target_schema.first); - if (!table) { +bool ObjectStore::needs_update(Schema const& old_schema, Schema const& schema) { + for (auto const& target_schema : schema) { + auto matching_schema = old_schema.find(target_schema); + if (matching_schema == end(old_schema)) { + // Table doesn't exist return true; } + + if (matching_schema->properties.size() != target_schema.properties.size()) { + // If the number of properties don't match then a migration is required + return false; + } + + // Check that all of the property indexes are up to date + for (size_t i = 0, count = target_schema.properties.size(); i < count; ++i) { + if (target_schema.properties[i].is_indexed != matching_schema->properties[i].is_indexed) { + return true; + } + } } - if (!indexes_are_up_to_date(group, schema)) { - return true; - } + return false; } -bool ObjectStore::update_realm_with_schema(Group *group, - uint64_t version, - Schema &schema, +bool ObjectStore::update_realm_with_schema(Group *group, Schema const& old_schema, + uint64_t version, Schema &schema, MigrationFunction migration) { // Recheck the schema version after beginning the write transaction as // another process may have done the migration after we opened the read @@ -353,7 +333,11 @@ bool ObjectStore::update_realm_with_schema(Group *group, bool changed = create_metadata_tables(group); changed = create_tables(group, schema, migrating) || changed; - verify_schema(group, schema); + if (!migrating) { + // If we aren't migrating, then verify that all of the tables which + // were already present are valid (newly created ones always are) + verify_schema(old_schema, schema, true); + } changed = update_indexes(group, schema) || changed; @@ -364,51 +348,34 @@ bool ObjectStore::update_realm_with_schema(Group *group, // apply the migration block if provided and there's any old data if (get_schema_version(group) != ObjectStore::NotVersioned) { migration(group, schema); - } - validate_primary_column_uniqueness(group, schema); + validate_primary_column_uniqueness(group, schema); + } set_schema_version(group, version); return true; } -Schema ObjectStore::schema_from_group(Group *group) { - Schema schema; +Schema ObjectStore::schema_from_group(const Group *group) { + std::vector schema; for (size_t i = 0; i < group->size(); i++) { std::string object_type = object_type_for_table_name(group->get_table_name(i)); if (object_type.length()) { - schema.emplace(object_type, std::move(ObjectSchema(group, object_type))); + schema.emplace_back(group, object_type); } } return schema; } -bool ObjectStore::indexes_are_up_to_date(Group *group, Schema &schema) { - for (auto &object_schema : schema) { - TableRef table = table_for_object_type(group, object_schema.first); - if (!table) { - continue; - } - - update_column_mapping(group, object_schema.second); - for (auto& property : object_schema.second.properties) { - if (property.requires_index() != table->has_search_index(property.table_column)) { - return false; - } - } - } - return true; -} - bool ObjectStore::update_indexes(Group *group, Schema &schema) { bool changed = false; for (auto& object_schema : schema) { - TableRef table = table_for_object_type(group, object_schema.first); + TableRef table = table_for_object_type(group, object_schema.name); if (!table) { continue; } - for (auto& property : object_schema.second.properties) { + for (auto& property : object_schema.properties) { if (property.requires_index() == table->has_search_index(property.table_column)) { continue; } @@ -419,7 +386,7 @@ bool ObjectStore::update_indexes(Group *group, Schema &schema) { table->add_search_index(property.table_column); } catch (LogicError const&) { - throw PropertyTypeNotIndexableException(object_schema.first, property); + throw PropertyTypeNotIndexableException(object_schema.name, property); } } else { @@ -430,16 +397,16 @@ bool ObjectStore::update_indexes(Group *group, Schema &schema) { return changed; } -void ObjectStore::validate_primary_column_uniqueness(Group *group, Schema &schema) { +void ObjectStore::validate_primary_column_uniqueness(const Group *group, Schema const& schema) { for (auto& object_schema : schema) { - auto primary_prop = object_schema.second.primary_key_property(); + auto primary_prop = object_schema.primary_key_property(); if (!primary_prop) { continue; } - TableRef table = table_for_object_type(group, object_schema.first); + ConstTableRef table = table_for_object_type(group, object_schema.name); if (table->get_distinct_view(primary_prop->table_column).size() != table->size()) { - throw DuplicatePrimaryKeyValueException(object_schema.first, *primary_prop); + throw DuplicatePrimaryKeyValueException(object_schema.name, *primary_prop); } } } @@ -460,62 +427,62 @@ InvalidSchemaVersionException::InvalidSchemaVersionException(uint64_t old_versio m_what = "Provided schema version " + std::to_string(old_version) + " is less than last set version " + std::to_string(new_version) + "."; } -DuplicatePrimaryKeyValueException::DuplicatePrimaryKeyValueException(std::string object_type, Property &property) : +DuplicatePrimaryKeyValueException::DuplicatePrimaryKeyValueException(std::string const& object_type, Property const& property) : m_object_type(object_type), m_property(property) { m_what = "Primary key property '" + property.name + "' has duplicate values after migration."; }; -SchemaValidationException::SchemaValidationException(std::vector errors) : +SchemaValidationException::SchemaValidationException(std::vector const& errors) : m_validation_errors(errors) { m_what ="Migration is required due to the following errors: "; - for (auto error : errors) { + for (auto const& error : errors) { m_what += std::string("\n- ") + error.what(); } } -PropertyTypeNotIndexableException::PropertyTypeNotIndexableException(std::string object_type, Property &property) : +PropertyTypeNotIndexableException::PropertyTypeNotIndexableException(std::string const& object_type, Property const& property) : ObjectSchemaPropertyException(object_type, property) { m_what = "Can't index property " + object_type + "." + property.name + ": indexing a property of type '" + string_for_property_type(property.type) + "' is currently not supported"; } -ExtraPropertyException::ExtraPropertyException(std::string object_type, Property &property) : +ExtraPropertyException::ExtraPropertyException(std::string const& object_type, Property const& property) : ObjectSchemaPropertyException(object_type, property) { m_what = "Property '" + property.name + "' has been added to latest object model."; } -MissingPropertyException::MissingPropertyException(std::string object_type, Property &property) : +MissingPropertyException::MissingPropertyException(std::string const& object_type, Property const& property) : ObjectSchemaPropertyException(object_type, property) { m_what = "Property '" + property.name + "' is missing from latest object model."; } -InvalidNullabilityException::InvalidNullabilityException(std::string object_type, Property &property) : +InvalidNullabilityException::InvalidNullabilityException(std::string const& object_type, Property const& property) : ObjectSchemaPropertyException(object_type, property) { if (property.type == PropertyTypeObject) { - if (!property.is_nullable) { - m_what = "'Object' property '" + property.name + "' must be nullable."; - } + m_what = "'Object' property '" + property.name + "' must be nullable."; } else { - if (property.is_nullable) { - m_what = "Only 'Object' property types are nullable"; - } +#if REALM_NULL_STRINGS == 1 + m_what = "Array or Mixed property '" + property.name + "' cannot be nullable"; +#else + m_what = "Only 'Object' property types are nullable"; +#endif } } -MissingObjectTypeException::MissingObjectTypeException(std::string object_type, Property &property) : +MissingObjectTypeException::MissingObjectTypeException(std::string const& object_type, Property const& property) : ObjectSchemaPropertyException(object_type, property) { m_what = "Target type '" + property.object_type + "' doesn't exist for property '" + property.name + "'."; } -MismatchedPropertiesException::MismatchedPropertiesException(std::string object_type, Property &old_property, Property &new_property) : +MismatchedPropertiesException::MismatchedPropertiesException(std::string const& object_type, Property const& old_property, Property const& new_property) : ObjectSchemaValidationException(object_type), m_old_property(old_property), m_new_property(new_property) { if (new_property.type != old_property.type) { @@ -530,7 +497,7 @@ MismatchedPropertiesException::MismatchedPropertiesException(std::string object_ } } -ChangedPrimaryKeyException::ChangedPrimaryKeyException(std::string object_type, std::string old_primary, std::string new_primary) : ObjectSchemaValidationException(object_type), m_old_primary(old_primary), m_new_primary(new_primary) +ChangedPrimaryKeyException::ChangedPrimaryKeyException(std::string const& object_type, std::string const& old_primary, std::string const& new_primary) : ObjectSchemaValidationException(object_type), m_old_primary(old_primary), m_new_primary(new_primary) { if (old_primary.size()) { m_what = "Property '" + old_primary + "' is no longer a primary key."; @@ -540,14 +507,13 @@ ChangedPrimaryKeyException::ChangedPrimaryKeyException(std::string object_type, } } -InvalidPrimaryKeyException::InvalidPrimaryKeyException(std::string object_type, std::string primary) : +InvalidPrimaryKeyException::InvalidPrimaryKeyException(std::string const& object_type, std::string const& primary) : ObjectSchemaValidationException(object_type), m_primary_key(primary) { m_what = "Specified primary key property '" + primary + "' does not exist."; } -DuplicatePrimaryKeysException::DuplicatePrimaryKeysException(std::string object_type) : ObjectSchemaValidationException(object_type) +DuplicatePrimaryKeysException::DuplicatePrimaryKeysException(std::string const& object_type) : ObjectSchemaValidationException(object_type) { m_what = "Duplicate primary keys for object '" + object_type + "'."; } - diff --git a/object_store.hpp b/object_store.hpp index cacdcd8b..f38524f8 100644 --- a/object_store.hpp +++ b/object_store.hpp @@ -19,18 +19,17 @@ #ifndef REALM_OBJECT_STORE_HPP #define REALM_OBJECT_STORE_HPP -#include -#include -#include -#include -#include - #include "object_schema.hpp" +#include "property.hpp" + +#include + +#include +#include namespace realm { class ObjectSchemaValidationException; - class Schema : public std::map { - }; + class Schema; class ObjectStore { public: @@ -38,37 +37,35 @@ namespace realm { static const uint64_t NotVersioned; // get the last set schema version - static uint64_t get_schema_version(Group *group); + static uint64_t get_schema_version(const Group *group); // checks if the schema in the group is at the given version - static bool is_schema_at_version(realm::Group *group, uint64_t version); + static bool is_schema_at_version(const Group *group, uint64_t version); - // verify a target schema against tables in the given group - // updates the column mapping on all ObjectSchema properties - // throws if the schema is invalid or does not match tables in the given group - static void verify_schema(Group *group, Schema &target_schema, bool allow_missing_tables = false); + // verify that schema from a group and a target schema are compatible + // updates the column mapping on all ObjectSchema properties of the target schema + // throws if the schema is invalid or does not match + static void verify_schema(Schema const& actual_schema, Schema& target_schema, bool allow_missing_tables = false); - // updates the target_column member for all properties based on the column indexes in the passed in group - static void update_column_mapping(Group *group, ObjectSchema &target_schema); - - // determines if you must call update_realm_with_schema for a given realm. - // returns true if there is a schema version mismatch, if there tables which still need to be created, - // or if file format or other changes/updates need to be made - static bool realm_requires_update(Group *group, uint64_t version, Schema &schema); + // determines if a realm with the given old schema needs non-migration + // changes to make it compatible with the given target schema + static bool needs_update(Schema const& old_schema, Schema const& schema); - // updates a Realm to a given target schema/version creating tables and updating indexes as necessary + // updates a Realm from old_schema to the given target schema, creating and updating tables as needed // returns if any changes were made - // passed in schema ar updated with the correct column mapping - // optionally runs migration function/lambda if schema is out of date + // passed in target schema is updated with the correct column mapping + // optionally runs migration function if schema is out of date // NOTE: must be performed within a write transaction typedef std::function MigrationFunction; - static bool update_realm_with_schema(Group *group, uint64_t version, Schema &schema, MigrationFunction migration); + static bool update_realm_with_schema(Group *group, Schema const& old_schema, uint64_t version, + Schema &schema, MigrationFunction migration); // get a table for an object type static realm::TableRef table_for_object_type(Group *group, StringData object_type); + static realm::ConstTableRef table_for_object_type(const Group *group, StringData object_type); // get existing Schema from a group - static Schema schema_from_group(Group *group); + static Schema schema_from_group(const Group *group); // deletes the table for the given type static void delete_data_for_object(Group *group, const StringData &object_type); @@ -78,7 +75,7 @@ namespace realm { static void set_schema_version(Group *group, uint64_t version); // check if the realm already has all metadata tables - static bool has_metadata_tables(Group *group); + static bool has_metadata_tables(const Group *group); // create any metadata tables that don't already exist // must be in write transaction to set @@ -89,13 +86,14 @@ namespace realm { // if update existing is true, updates existing tables, otherwise only adds and initializes new tables static bool create_tables(realm::Group *group, Schema &target_schema, bool update_existing); - // verify a target schema against its table, setting the table_column property on each schema object + // verify a target schema against an expected schema, setting the table_column property on each schema object // updates the column mapping on the target_schema // returns array of validation errors - static std::vector verify_object_schema(Group *group, ObjectSchema &target_schema, Schema &schema); + static std::vector verify_object_schema(ObjectSchema const& expected, + ObjectSchema &target_schema); // get primary key property name for object type - static StringData get_primary_key_for_object(Group *group, StringData object_type); + static StringData get_primary_key_for_object(const Group *group, StringData object_type); // sets primary key property for object type // must be in write transaction to set @@ -105,14 +103,11 @@ namespace realm { static std::string table_name_for_object_type(const std::string &class_name); static std::string object_type_for_table_name(const std::string &table_name); - // check if indexes are up to date - if false you need to call update_realm_with_schema - static bool indexes_are_up_to_date(Group *group, Schema &schema); - // returns if any indexes were changed static bool update_indexes(Group *group, Schema &schema); // validates that all primary key properties have unique values - static void validate_primary_column_uniqueness(Group *group, Schema &schema); + static void validate_primary_column_uniqueness(const Group *group, Schema const& schema); friend ObjectSchema; }; @@ -122,7 +117,7 @@ namespace realm { public: ObjectStoreException() = default; ObjectStoreException(const std::string &what) : m_what(what) {} - virtual const char* what() const noexcept { return m_what.c_str(); } + const char* what() const noexcept override { return m_what.c_str(); } protected: std::string m_what; }; @@ -133,17 +128,17 @@ namespace realm { class InvalidSchemaVersionException : public MigrationException { public: InvalidSchemaVersionException(uint64_t old_version, uint64_t new_version); - uint64_t old_version() { return m_old_version; } - uint64_t new_version() { return m_new_version; } + uint64_t old_version() const { return m_old_version; } + uint64_t new_version() const { return m_new_version; } private: uint64_t m_old_version, m_new_version; }; class DuplicatePrimaryKeyValueException : public MigrationException { public: - DuplicatePrimaryKeyValueException(std::string object_type, Property &property); - std::string object_type() { return m_object_type; } - Property &property() { return m_property; } + DuplicatePrimaryKeyValueException(std::string const& object_type, Property const& property); + std::string object_type() const { return m_object_type; } + Property const& property() const { return m_property; } private: std::string m_object_type; Property m_property; @@ -152,87 +147,86 @@ namespace realm { // Schema validation exceptions class SchemaValidationException : public ObjectStoreException { public: - SchemaValidationException(std::vector errors); - std::vector &validation_errors() { return m_validation_errors; } + SchemaValidationException(std::vector const& errors); + std::vector const& validation_errors() const { return m_validation_errors; } private: std::vector m_validation_errors; }; class ObjectSchemaValidationException : public ObjectStoreException { public: - ObjectSchemaValidationException(std::string object_type) : m_object_type(object_type) {} - ObjectSchemaValidationException(std::string object_type, std::string message) : + ObjectSchemaValidationException(std::string const& object_type) : m_object_type(object_type) {} + ObjectSchemaValidationException(std::string const& object_type, std::string const& message) : m_object_type(object_type) { m_what = message; } - std::string object_type() { return m_object_type; } + std::string object_type() const { return m_object_type; } protected: std::string m_object_type; }; class ObjectSchemaPropertyException : public ObjectSchemaValidationException { public: - ObjectSchemaPropertyException(std::string object_type, Property &property) : + ObjectSchemaPropertyException(std::string const& object_type, Property const& property) : ObjectSchemaValidationException(object_type), m_property(property) {} - Property &property() { return m_property; } + Property const& property() const { return m_property; } private: Property m_property; }; class PropertyTypeNotIndexableException : public ObjectSchemaPropertyException { public: - PropertyTypeNotIndexableException(std::string object_type, Property &property); + PropertyTypeNotIndexableException(std::string const& object_type, Property const& property); }; class ExtraPropertyException : public ObjectSchemaPropertyException { public: - ExtraPropertyException(std::string object_type, Property &property); + ExtraPropertyException(std::string const& object_type, Property const& property); }; class MissingPropertyException : public ObjectSchemaPropertyException { public: - MissingPropertyException(std::string object_type, Property &property); + MissingPropertyException(std::string const& object_type, Property const& property); }; class InvalidNullabilityException : public ObjectSchemaPropertyException { public: - InvalidNullabilityException(std::string object_type, Property &property); + InvalidNullabilityException(std::string const& object_type, Property const& property); }; class MissingObjectTypeException : public ObjectSchemaPropertyException { public: - MissingObjectTypeException(std::string object_type, Property &property); + MissingObjectTypeException(std::string const& object_type, Property const& property); }; class DuplicatePrimaryKeysException : public ObjectSchemaValidationException { public: - DuplicatePrimaryKeysException(std::string object_type); + DuplicatePrimaryKeysException(std::string const& object_type); }; class MismatchedPropertiesException : public ObjectSchemaValidationException { public: - MismatchedPropertiesException(std::string object_type, Property &old_property, Property &new_property); - Property &old_property() { return m_old_property; } - Property &new_property() { return m_new_property; } + MismatchedPropertiesException(std::string const& object_type, Property const& old_property, Property const& new_property); + Property const& old_property() const { return m_old_property; } + Property const& new_property() const { return m_new_property; } private: Property m_old_property, m_new_property; }; class ChangedPrimaryKeyException : public ObjectSchemaValidationException { public: - ChangedPrimaryKeyException(std::string object_type, std::string old_primary, std::string new_primary); - std::string old_primary() { return m_old_primary; } - std::string new_primary() { return m_new_primary; } + ChangedPrimaryKeyException(std::string const& object_type, std::string const& old_primary, std::string const& new_primary); + std::string old_primary() const { return m_old_primary; } + std::string new_primary() const { return m_new_primary; } private: std::string m_old_primary, m_new_primary; }; class InvalidPrimaryKeyException : public ObjectSchemaValidationException { public: - InvalidPrimaryKeyException(std::string object_type, std::string primary_key); - std::string primary_key() { return m_primary_key; } + InvalidPrimaryKeyException(std::string const& object_type, std::string const& primary_key); + std::string primary_key() const { return m_primary_key; } private: std::string m_primary_key; }; } #endif /* defined(REALM_OBJECT_STORE_HPP) */ - diff --git a/property.hpp b/property.hpp index 22e6f90c..3883e805 100644 --- a/property.hpp +++ b/property.hpp @@ -46,18 +46,15 @@ namespace realm { }; struct Property { - public: - Property() : object_type(""), is_primary(false), is_indexed(false), is_nullable(false) {} - std::string name; PropertyType type; std::string object_type; - bool is_primary; - bool is_indexed; - bool is_nullable; + bool is_primary = false; + bool is_indexed = false; + bool is_nullable = false; size_t table_column; - bool requires_index() { return is_primary || is_indexed; } + bool requires_index() const { return is_primary || is_indexed; } }; static inline const char *string_for_property_type(PropertyType type) { diff --git a/realm_delegate.hpp b/realm_delegate.hpp new file mode 100644 index 00000000..0d9e9dfe --- /dev/null +++ b/realm_delegate.hpp @@ -0,0 +1,154 @@ +//////////////////////////////////////////////////////////////////////////// +// +// Copyright 2015 Realm Inc. +// +// 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. +// +//////////////////////////////////////////////////////////////////////////// + +#ifndef REALM_DELEGATE_HPP +#define REALM_DELEGATE_HPP + +#include "index_set.hpp" + +#include +#include + +namespace realm { +// RealmDelegate is the extension point for adding binding-specific behavior to +// a SharedRealm. It can be used to store additonal data associated with the +// Realm which is needed by the binding, and there are several methods which +// can be overridden to receive notifications of state changes within the Realm. +// +// A simple delegate implementation which lets the user register functions to be +// called on refresh could look like the following: +// +// class DelegateImplementation : public RealmDelegate { +// public: +// // A token returned from add_notification that can be used to remove the +// // notification later +// struct token : private std::list>::iterator { +// token(std::list>::iterator it) : std::list>::iterator(it) { } +// friend class DelegateImplementation; +// }; +// +// token add_notification(std::function func) +// { +// m_registered_notifications.push_back(std::move(func)); +// return token(std::prev(m_registered_notifications.end())); +// } +// +// void remove_notification(token entry) +// { +// m_registered_notifications.erase(entry); +// } +// +// // Override the did_change method to call each registered notification +// void did_change(std::vector const&, std::vector const&) override +// { +// // Loop oddly so that unregistering a notification from within the +// // registered function works +// for (auto it = m_registered_notifications.begin(); it != m_registered_notifications.end(); ) { +// (*it++)(); +// } +// } +// +// private: +// std::list> m_registered_notifications; +// }; +class RealmDelegate { +public: + virtual ~RealmDelegate() = default; + + // Called by the Realm when a write transaction is committed to the file by + // a different Realm instance (possibly in a different process) + virtual void changes_available() { } + + struct ObserverState; + + // Override this function if you want to recieve detailed information about + // external changes to a specific set of objects. + // This is called before each operation which may advance the read + // transaction to include + // ObserverStates for each row for which detailed change information is + // desired. + virtual std::vector get_observed_rows() { return {}; } + + // Called immediately before the read transaction is advanced if detailed + // change information was requested (by returning a non-empty array from + // get_observed_rows()). + // The observers vector is the vector returned by get_observed_row(), + // updated with change information. The invalidated vector is a list of the + // `info` fields of observed rows which will be deleted. + virtual void will_change(std::vector const& observers, + std::vector const& invalidated); + + // Called immediately after the read transaction version is advanced. Unlike + // will_change(), this is called even if detailed change information was not + // requested or if the Realm is not actually in a read transactuib, although + // both vectors will be empty in that case. + virtual void did_change(std::vector const& observers, + std::vector const& invalidated); + + // Change information for a single field of a row + struct ColumnInfo { + // Did this column change? + bool changed = false; + // For LinkList columns, what kind of change occurred? + // Always None for other column types + enum class Kind { + None, // No change + Set, // The entries at `indices` were assigned to + Insert, // New values were inserted at each of the indices given + Remove, // Values were removed at each of the indices given + SetAll // The entire LinkList has been replaced with a new set of values + } kind = Kind::None; + // The indices where things happened for Set, Insert and Remove + // Not used for None and SetAll + IndexSet indices; + }; + + // Information about an observed row in a table + // + // Each object which needs detailed change information should have an + // ObserverState entry in the vector returned from get_observed_rows(), with + // the initial table and row indexes set (and optionally the info field). + // The Realm parses the transaction log, and populates the `changes` vector + // in each ObserverState with information about what changes were made. + struct ObserverState { + // Initial table and row which is observed + // May be updated by row insertions and removals + size_t table_ndx; + size_t row_ndx; + + // Opaque userdata for the delegate's use + void* info; + + // Populated with information about which columns were changed + // May be shorter than the actual number of columns if the later columns + // are not modified + std::vector changes; + + // Simple lexographic ordering + friend bool operator<(ObserverState const& lft, ObserverState const& rgt) + { + return std::tie(lft.table_ndx, lft.row_ndx) < std::tie(rgt.table_ndx, rgt.row_ndx); + } + }; +}; + +inline void RealmDelegate::will_change(std::vector const&, std::vector const&) { } +inline void RealmDelegate::did_change(std::vector const&, std::vector const&) { } +} // namespace realm + +#endif /* REALM_DELEGATE_HPP */ diff --git a/schema.cpp b/schema.cpp new file mode 100644 index 00000000..bf7a6181 --- /dev/null +++ b/schema.cpp @@ -0,0 +1,106 @@ +//////////////////////////////////////////////////////////////////////////// +// +// Copyright 2015 Realm Inc. +// +// 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 "schema.hpp" + +#include "object_schema.hpp" +#include "object_store.hpp" +#include "property.hpp" + +using namespace realm; + +static bool compare_by_name(ObjectSchema const& lft, ObjectSchema const& rgt) { + return lft.name < rgt.name; +} + +Schema::Schema(base types) : base(std::move(types)) { + std::sort(begin(), end(), compare_by_name); +} + +Schema::iterator Schema::find(std::string const& name) +{ + ObjectSchema cmp; + cmp.name = name; + return find(cmp); +} + +Schema::const_iterator Schema::find(std::string const& name) const +{ + return const_cast(this)->find(name); +} + +Schema::iterator Schema::find(ObjectSchema const& object) noexcept +{ + auto it = std::lower_bound(begin(), end(), object, compare_by_name); + if (it != end() && it->name != object.name) { + it = end(); + } + return it; +} + +Schema::const_iterator Schema::find(ObjectSchema const& object) const noexcept +{ + return const_cast(this)->find(object); +} + +void Schema::validate() const +{ + std::vector exceptions; + for (auto const& object : *this) { + const Property *primary = nullptr; + for (auto const& prop : object.properties) { + // check object_type existence + if (!prop.object_type.empty() && find(prop.object_type) == end()) { + exceptions.emplace_back(MissingObjectTypeException(object.name, prop)); + } + + // check nullablity + if (prop.is_nullable) { +#if REALM_NULL_STRINGS == 1 + if (prop.type == PropertyTypeArray || prop.type == PropertyTypeAny) { +#else + if (prop.type != PropertyTypeObject) { +#endif + exceptions.emplace_back(InvalidNullabilityException(object.name, prop)); + } + } + else if (prop.type == PropertyTypeObject) { + exceptions.emplace_back(InvalidNullabilityException(object.name, prop)); + } + + // check primary keys + if (prop.is_primary) { + if (primary) { + exceptions.emplace_back(DuplicatePrimaryKeysException(object.name)); + } + primary = ∝ + } + + // check indexable + if (prop.is_indexed) { + if (prop.type != PropertyTypeString && prop.type != PropertyTypeInt) { + exceptions.emplace_back(PropertyTypeNotIndexableException(object.name, prop)); + } + } + } + } + + if (exceptions.size()) { + throw SchemaValidationException(exceptions); + } +} diff --git a/schema.hpp b/schema.hpp new file mode 100644 index 00000000..0a7fa425 --- /dev/null +++ b/schema.hpp @@ -0,0 +1,55 @@ +//////////////////////////////////////////////////////////////////////////// +// +// Copyright 2015 Realm Inc. +// +// 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. +// +//////////////////////////////////////////////////////////////////////////// + +#ifndef REALM_SCHEMA_HPP +#define REALM_SCHEMA_HPP + +#include + +namespace realm { +class ObjectSchema; + +class Schema : private std::vector { +private: + using base = std::vector; +public: + // Create a schema from a vector of ObjectSchema + Schema(base types); + + // find an ObjectSchema by name + iterator find(std::string const& name); + const_iterator find(std::string const& name) const; + + // find an ObjectSchema with the same name as the passed in one + iterator find(ObjectSchema const& object) noexcept; + const_iterator find(ObjectSchema const& object) const noexcept; + + // Verify that this schema is internally consistent (i.e. all properties are + // valid, links link to types that actually exist, etc.) + void validate() const; + + using base::iterator; + using base::const_iterator; + using base::begin; + using base::end; + using base::empty; + using base::size; +}; +} + +#endif /* defined(REALM_SCHEMA_HPP) */ \ No newline at end of file diff --git a/shared_realm.cpp b/shared_realm.cpp index a7269591..8b003d30 100644 --- a/shared_realm.cpp +++ b/shared_realm.cpp @@ -17,47 +17,69 @@ //////////////////////////////////////////////////////////////////////////// #include "shared_realm.hpp" -#include -#include + +#include "external_commit_helper.hpp" +#include "realm_delegate.hpp" +#include "schema.hpp" +#include "transact_log_handler.hpp" + #include -#include +#include + +#include using namespace realm; RealmCache Realm::s_global_cache; -std::mutex Realm::s_init_mutex; -Realm::Config::Config(const Config& c) : path(c.path), read_only(c.read_only), in_memory(c.in_memory), schema_version(c.schema_version), encryption_key(c.encryption_key), migration_function(c.migration_function) +Realm::Config::Config(const Config& c) +: path(c.path) +, read_only(c.read_only) +, in_memory(c.in_memory) +, cache(c.cache) +, encryption_key(c.encryption_key) +, schema_version(c.schema_version) +, migration_function(c.migration_function) { if (c.schema) { schema = std::make_unique(*c.schema); } } -Realm::Realm(Config &config) : m_config(config), m_thread_id(std::this_thread::get_id()), m_auto_refresh(true), m_in_transaction(false) +Realm::Config::~Config() = default; + +Realm::Config& Realm::Config::operator=(realm::Realm::Config const& c) +{ + if (&c != this) { + *this = Config(c); + } + return *this; +} + +Realm::Realm(Config config) +: m_config(std::move(config)) { try { - if (config.read_only) { - m_read_only_group = std::make_unique(config.path, config.encryption_key.data(), Group::mode_ReadOnly); + if (m_config.read_only) { + m_read_only_group = std::make_unique(m_config.path, m_config.encryption_key.data(), Group::mode_ReadOnly); m_group = m_read_only_group.get(); } else { - m_history = realm::make_client_history(config.path, config.encryption_key.data()); - SharedGroup::DurabilityLevel durability = config.in_memory ? SharedGroup::durability_MemOnly : - SharedGroup::durability_Full; - m_shared_group = std::make_unique(*m_history, durability, config.encryption_key.data()); - m_group = nullptr; + m_history = realm::make_client_history(m_config.path, m_config.encryption_key.data()); + SharedGroup::DurabilityLevel durability = m_config.in_memory ? SharedGroup::durability_MemOnly : + SharedGroup::durability_Full; + m_shared_group = std::make_unique(*m_history, durability, m_config.encryption_key.data()); } } catch (util::File::PermissionDenied const& ex) { - throw RealmFileException(RealmFileException::Kind::PermissionDenied, "Unable to open a realm at path '" + config.path + - "'. Please use a path where your app has " + (config.read_only ? "read" : "read-write") + " permissions."); + throw RealmFileException(RealmFileException::Kind::PermissionDenied, "Unable to open a realm at path '" + m_config.path + + "'. Please use a path where your app has " + (m_config.read_only ? "read" : "read-write") + " permissions."); } catch (util::File::Exists const& ex) { - throw RealmFileException(RealmFileException::Kind::Exists, "Unable to open a realm at path '" + config.path + "'"); + throw RealmFileException(RealmFileException::Kind::Exists, "Unable to open a realm at path '" + m_config.path + "'"); } catch (util::File::AccessError const& ex) { - throw RealmFileException(RealmFileException::Kind::AccessError, "Unable to open a realm at path '" + config.path + "'"); + throw RealmFileException(RealmFileException::Kind::AccessError, "Unable to open a realm at path '" + m_config.path + "'"); } catch (IncompatibleLockFile const&) { throw RealmFileException(RealmFileException::Kind::IncompatibleLockFile, "Realm file is currently open in another process " @@ -65,6 +87,12 @@ Realm::Realm(Config &config) : m_config(config), m_thread_id(std::this_thread::g } } +Realm::~Realm() { + if (m_notifier) { // might not exist yet if an error occurred during init + m_notifier->remove_realm(this); + } +} + Group *Realm::read_group() { if (!m_group) { @@ -73,90 +101,114 @@ Group *Realm::read_group() return m_group; } -SharedRealm Realm::get_shared_realm(Config &config) +SharedRealm Realm::get_shared_realm(Config config) { - SharedRealm realm = s_global_cache.get_realm(config.path); - if (realm) { - if (realm->config().read_only != config.read_only) { - throw MismatchedConfigException("Realm at path already opened with different read permissions."); - } - if (realm->config().in_memory != config.in_memory) { - throw MismatchedConfigException("Realm at path already opened with different inMemory settings."); - } - if (realm->config().encryption_key != config.encryption_key) { - throw MismatchedConfigException("Realm at path already opened with a different encryption key."); - } - if (realm->config().schema_version != config.schema_version && config.schema_version != ObjectStore::NotVersioned) { - throw MismatchedConfigException("Realm at path already opened with different schema version."); - } - // FIXME - enable schma comparison - /*if (realm->config().schema != config.schema) { - throw MismatchedConfigException("Realm at path already opened with different schema"); - }*/ + if (config.cache) { + if (SharedRealm realm = s_global_cache.get_realm(config.path)) { + if (realm->config().read_only != config.read_only) { + throw MismatchedConfigException("Realm at path already opened with different read permissions."); + } + if (realm->config().in_memory != config.in_memory) { + throw MismatchedConfigException("Realm at path already opened with different inMemory settings."); + } + if (realm->config().encryption_key != config.encryption_key) { + throw MismatchedConfigException("Realm at path already opened with a different encryption key."); + } + if (realm->config().schema_version != config.schema_version && config.schema_version != ObjectStore::NotVersioned) { + throw MismatchedConfigException("Realm at path already opened with different schema version."); + } + // FIXME - enable schma comparison + /*if (realm->config().schema != config.schema) { + throw MismatchedConfigException("Realm at path already opened with different schema"); + }*/ + realm->m_config.migration_function = config.migration_function; - realm->m_config.migration_function = config.migration_function; - - return realm; + return realm; + } } - realm = SharedRealm(new Realm(config)); + SharedRealm realm(new Realm(std::move(config))); + + auto target_schema = std::move(realm->m_config.schema); + auto target_schema_version = realm->m_config.schema_version; + realm->m_config.schema_version = ObjectStore::get_schema_version(realm->read_group()); // we want to ensure we are only initializing a single realm at a time + static std::mutex s_init_mutex; std::lock_guard lock(s_init_mutex); - - uint64_t old_version = ObjectStore::get_schema_version(realm->read_group()); if (auto existing = s_global_cache.get_any_realm(realm->config().path)) { // if there is an existing realm at the current path steal its schema/column mapping // FIXME - need to validate that schemas match realm->m_config.schema = std::make_unique(*existing->m_config.schema); - } - else if (!realm->m_config.schema) { - // get schema from group and skip validation - realm->m_config.schema_version = old_version; - realm->m_config.schema = std::make_unique(ObjectStore::schema_from_group(realm->read_group())); - } - else if (realm->m_config.read_only) { - if (old_version == ObjectStore::NotVersioned) { - throw UnitializedRealmException("Can't open an un-initizliazed Realm without a Schema"); - } - ObjectStore::verify_schema(realm->read_group(), *realm->m_config.schema, true); + + realm->m_notifier = existing->m_notifier; + realm->m_notifier->add_realm(realm.get()); } else { - // its a non-cached realm so update/migrate if needed - realm->update_schema(*realm->m_config.schema, realm->m_config.schema_version); + realm->m_notifier = std::make_shared(realm.get()); + + // otherwise get the schema from the group + realm->m_config.schema = std::make_unique(ObjectStore::schema_from_group(realm->read_group())); + + // if a target schema is supplied, verify that it matches or migrate to + // it, as neeeded + if (target_schema) { + if (realm->m_config.read_only) { + if (realm->m_config.schema_version == ObjectStore::NotVersioned) { + throw UnitializedRealmException("Can't open an un-initialized Realm without a Schema"); + } + target_schema->validate(); + ObjectStore::verify_schema(*realm->m_config.schema, *target_schema, true); + realm->m_config.schema = std::move(target_schema); + } + else { + realm->update_schema(std::move(target_schema), target_schema_version); + } + } } - s_global_cache.cache_realm(realm, realm->m_thread_id); + if (config.cache) { + s_global_cache.cache_realm(realm, realm->m_thread_id); + } return realm; } -bool Realm::update_schema(Schema &schema, uint64_t version) +bool Realm::update_schema(std::unique_ptr schema, uint64_t version) { - bool changed = false; - Config old_config(m_config); + schema->validate(); - // set new version/schema - if (m_config.schema.get() != &schema) { - m_config.schema = std::make_unique(schema); + bool needs_update = !m_config.read_only && (m_config.schema_version != version || ObjectStore::needs_update(*m_config.schema, *schema)); + if (!needs_update) { + ObjectStore::verify_schema(*m_config.schema, *schema, m_config.read_only); + m_config.schema = std::move(schema); + m_config.schema_version = version; + return false; } + + // Store the old config/schema for the migration function, and update + // our schema to the new one + auto old_schema = std::move(m_config.schema); + Config old_config(m_config); + old_config.read_only = true; + old_config.schema = std::move(old_schema); + + m_config.schema = std::move(schema); m_config.schema_version = version; - try { - if (!m_config.read_only && ObjectStore::realm_requires_update(read_group(), version, schema)) { - // keep old copy to pass to migration function - old_config.read_only = true; - SharedRealm old_realm = SharedRealm(new Realm(old_config)), updated_realm = shared_from_this(); + auto migration_function = [&](Group*, Schema&) { + SharedRealm old_realm(new Realm(old_config)); + auto updated_realm = shared_from_this(); + m_config.migration_function(old_realm, updated_realm); + }; - // update and migrate - begin_transaction(); - changed = ObjectStore::update_realm_with_schema(read_group(), version, *m_config.schema, [=](__unused Group *group, __unused Schema &target_schema) { - m_config.migration_function(old_realm, updated_realm); - }); - commit_transaction(); - } - else { - ObjectStore::verify_schema(read_group(), *m_config.schema, m_config.read_only); - } + try { + // update and migrate + begin_transaction(); + bool changed = ObjectStore::update_realm_with_schema(read_group(), *old_config.schema, + version, *m_config.schema, + migration_function); + commit_transaction(); + return changed; } catch (...) { if (is_in_transaction()) { @@ -166,7 +218,6 @@ bool Realm::update_schema(Schema &schema, uint64_t version) m_config.schema = std::move(old_config.schema); throw; } - return changed; } static void check_read_write(Realm *realm) @@ -176,7 +227,7 @@ static void check_read_write(Realm *realm) } } -void Realm::verify_thread() +void Realm::verify_thread() const { if (m_thread_id != std::this_thread::get_id()) { throw IncorrectThreadException("Realm accessed from incorrect thread."); @@ -192,18 +243,11 @@ void Realm::begin_transaction() throw InvalidTransactionException("The Realm is already in a write transaction"); } - // if the upgrade to write will move the transaction forward, announce the change after promoting - bool announce = m_shared_group->has_changed(); - // make sure we have a read transaction read_group(); - LangBindHelper::promote_to_write(*m_shared_group, *m_history); + transaction::begin(*m_shared_group, *m_history, m_delegate.get()); m_in_transaction = true; - - if (announce) { - send_local_notifications(DidChangeNotification); - } } void Realm::commit_transaction() @@ -215,11 +259,9 @@ void Realm::commit_transaction() throw InvalidTransactionException("Can't commit a non-existing write transaction"); } - LangBindHelper::commit_and_continue_as_read(*m_shared_group); m_in_transaction = false; - - send_external_notifications(); - send_local_notifications(DidChangeNotification); + transaction::commit(*m_shared_group, *m_history, m_delegate.get()); + m_notifier->notify_others(); } void Realm::cancel_transaction() @@ -231,11 +273,10 @@ void Realm::cancel_transaction() throw InvalidTransactionException("Can't cancel a non-existing write transaction"); } - LangBindHelper::rollback_and_continue_as_read(*m_shared_group, *m_history); m_in_transaction = false; + transaction::cancel(*m_shared_group, *m_history, m_delegate.get()); } - void Realm::invalidate() { verify_thread(); @@ -256,20 +297,21 @@ bool Realm::compact() { verify_thread(); - bool success = false; + if (m_config.read_only) { + throw InvalidTransactionException("Can't compact a read-only Realm"); + } if (m_in_transaction) { throw InvalidTransactionException("Can't compact a Realm within a write transaction"); } + Group* group = read_group(); for (auto &object_schema : *m_config.schema) { - ObjectStore::table_for_object_type(read_group(), object_schema.first)->optimize(); + ObjectStore::table_for_object_type(group, object_schema.name)->optimize(); } - m_shared_group->end_read(); - success = m_shared_group->compact(); - m_shared_group->begin_read(); + m_group = nullptr; - return success; + return m_shared_group->compact(); } void Realm::notify() @@ -277,24 +319,17 @@ void Realm::notify() verify_thread(); if (m_shared_group->has_changed()) { // Throws + if (m_delegate) { + m_delegate->changes_available(); + } if (m_auto_refresh) { if (m_group) { - LangBindHelper::advance_read(*m_shared_group, *m_history); + transaction::advance(*m_shared_group, *m_history, m_delegate.get()); + } + else if (m_delegate) { + m_delegate->did_change({}, {}); } - send_local_notifications(DidChangeNotification); } - else { - send_local_notifications(RefreshRequiredNotification); - } - } -} - - -void Realm::send_local_notifications(const std::string &type) -{ - verify_thread(); - for (NotificationFunction notification : m_notifications) { - (*notification)(type); } } @@ -315,17 +350,25 @@ bool Realm::refresh() } if (m_group) { - LangBindHelper::advance_read(*m_shared_group, *m_history); + transaction::advance(*m_shared_group, *m_history, m_delegate.get()); } else { // Create the read transaction read_group(); } - send_local_notifications(DidChangeNotification); return true; } +uint64_t Realm::get_schema_version(const realm::Realm::Config &config) +{ + if (auto existing_realm = s_global_cache.get_any_realm(config.path)) { + return existing_realm->config().schema_version; + } + + return ObjectStore::get_schema_version(Realm(config).read_group()); +} + SharedRealm RealmCache::get_realm(const std::string &path, std::thread::id thread_id) { std::lock_guard lock(m_mutex); @@ -401,4 +444,3 @@ void RealmCache::clear() m_cache.clear(); } - diff --git a/shared_realm.hpp b/shared_realm.hpp index af8b774a..aa19071e 100644 --- a/shared_realm.hpp +++ b/shared_realm.hpp @@ -19,21 +19,21 @@ #ifndef REALM_REALM_HPP #define REALM_REALM_HPP +#include #include #include #include -#include -#include -#include #include "object_store.hpp" namespace realm { - class RealmCache; + class ClientHistory; + class ExternalCommitHelper; class Realm; + class RealmCache; + class RealmDelegate; typedef std::shared_ptr SharedRealm; typedef std::weak_ptr WeakRealm; - class ClientHistory; class Realm : public std::enable_shared_from_this { @@ -43,83 +43,81 @@ namespace realm { struct Config { std::string path; - bool read_only; - bool in_memory; - StringData encryption_key; + bool read_only = false; + bool in_memory = false; + bool cache = true; + std::vector encryption_key; std::unique_ptr schema; - uint64_t schema_version; + uint64_t schema_version = ObjectStore::NotVersioned; MigrationFunction migration_function; - Config() : read_only(false), in_memory(false), schema_version(ObjectStore::NotVersioned) {}; + Config() = default; + Config(Config&&) = default; Config(const Config& c); + ~Config(); + + Config& operator=(Config const&); + Config& operator=(Config&&) = default; }; // Get a cached Realm or create a new one if no cached copies exists - // Caching is done by path - mismatches for inMemory and readOnly Config properties - // will raise an exception - // If schema/schema_version is specified, update_schema is called automatically on the realm - // and a migration is performed. If not specified, the schema version and schema are dynamically - // read from the the existing Realm. - static SharedRealm get_shared_realm(Config &config); + // Caching is done by path - mismatches for in_memory and read_only + // Config properties will raise an exception + // If schema/schema_version is specified, update_schema is called + // automatically on the realm and a migration is performed. If not + // specified, the schema version and schema are dynamically read from + // the the existing Realm. + static SharedRealm get_shared_realm(Config config); - // Updates a Realm to a given target schema/version creating tables and updating indexes as necessary - // Uses the existing migration function on the Config, and the resulting Schema and version with updated + // Updates a Realm to a given target schema/version creating tables and + // updating indexes as necessary. Uses the existing migration function + // on the Config, and the resulting Schema and version with updated // column mappings are set on the realms config upon success. // returns if any changes were made - bool update_schema(Schema &schema, uint64_t version); + bool update_schema(std::unique_ptr schema, uint64_t version); + + static uint64_t get_schema_version(Config const& config); const Config &config() const { return m_config; } void begin_transaction(); void commit_transaction(); void cancel_transaction(); - bool is_in_transaction() { return m_in_transaction; } + bool is_in_transaction() const { return m_in_transaction; } bool refresh(); void set_auto_refresh(bool auto_refresh) { m_auto_refresh = auto_refresh; } - bool auto_refresh() { return m_auto_refresh; } + bool auto_refresh() const { return m_auto_refresh; } void notify(); - typedef std::shared_ptr> NotificationFunction; - void add_notification(NotificationFunction ¬ification) { m_notifications.insert(notification); } - void remove_notification(NotificationFunction notification) { m_notifications.erase(notification); } - void remove_all_notifications() { m_notifications.clear(); } - void invalidate(); bool compact(); std::thread::id thread_id() const { return m_thread_id; } - void verify_thread(); + void verify_thread() const; - const std::string RefreshRequiredNotification = "RefreshRequiredNotification"; - const std::string DidChangeNotification = "DidChangeNotification"; + ~Realm(); private: - Realm(Config &config); + Realm(Config config); Config m_config; - std::thread::id m_thread_id; - bool m_in_transaction; - bool m_auto_refresh; - - std::set m_notifications; - void send_local_notifications(const std::string ¬ification); - - typedef std::unique_ptr> ExternalNotificationFunction; - void send_external_notifications() { if (m_external_notifier) (*m_external_notifier)(); } + std::thread::id m_thread_id = std::this_thread::get_id(); + bool m_in_transaction = false; + bool m_auto_refresh = true; std::unique_ptr m_history; std::unique_ptr m_shared_group; std::unique_ptr m_read_only_group; - Group *m_group; + Group *m_group = nullptr; - static std::mutex s_init_mutex; + std::shared_ptr m_notifier; public: - ExternalNotificationFunction m_external_notifier; + std::unique_ptr m_delegate; // FIXME private Group *read_group(); diff --git a/transact_log_handler.cpp b/transact_log_handler.cpp new file mode 100644 index 00000000..3f833b19 --- /dev/null +++ b/transact_log_handler.cpp @@ -0,0 +1,347 @@ +//////////////////////////////////////////////////////////////////////////// +// +// Copyright 2015 Realm Inc. +// +// 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 "transact_log_handler.hpp" + +#include "realm_delegate.hpp" + +#include +#include +#include + +using namespace realm; + +namespace { +class TransactLogHandler { + using ColumnInfo = RealmDelegate::ColumnInfo; + using ObserverState = RealmDelegate::ObserverState; + + // Observed table rows which need change information + std::vector m_observers; + // Userdata pointers for rows which have been deleted + std::vector invalidated; + // Delegate to send change information to + RealmDelegate* m_delegate; + + // Index of currently selected table + size_t m_current_table = 0; + // Change information for the currently selected LinkList, if any + ColumnInfo* m_active_linklist = nullptr; + + // Get the change info for the given column, creating it if needed + static ColumnInfo& get_change(ObserverState& state, size_t i) + { + if (state.changes.size() <= i) { + state.changes.resize(std::max(state.changes.size() * 2, i + 1)); + } + return state.changes[i]; + } + + // Loop over the columns which were changed in an observer state + template + static void for_each(ObserverState& state, Func&& f) + { + for (size_t i = 0; i < state.changes.size(); ++i) { + auto const& change = state.changes[i]; + if (change.changed) { + f(i, change); + } + } + } + + // Mark the given row/col as needing notifications sent + bool mark_dirty(size_t row_ndx, size_t col_ndx) + { + auto it = lower_bound(begin(m_observers), end(m_observers), ObserverState{m_current_table, row_ndx, nullptr}); + if (it != end(m_observers) && it->table_ndx == m_current_table && it->row_ndx == row_ndx) { + get_change(*it, col_ndx).changed = true; + } + return true; + } + + // Remove the given observer from the list of observed objects and add it + // to the listed of invalidated objects + void invalidate(ObserverState *o) + { + invalidated.push_back(o->info); + m_observers.erase(m_observers.begin() + (o - &m_observers[0])); + } + +public: + template + TransactLogHandler(RealmDelegate* delegate, SharedGroup& sg, Func&& func) + : m_delegate(delegate) + { + if (!delegate) { + func(); + return; + } + + m_observers = delegate->get_observed_rows(); + if (m_observers.empty()) { + auto old_version = sg.get_version_of_current_transaction(); + func(); + if (old_version != sg.get_version_of_current_transaction()) { + delegate->did_change({}, {}); + } + return; + } + + func(*this); + delegate->did_change(m_observers, invalidated); + } + + // Called at the end of the transaction log immediately before the version + // is advanced + void parse_complete() + { + m_delegate->will_change(m_observers, invalidated); + } + + // These would require having an observer before schema init + // Maybe do something here to throw an error when multiple processes have different schemas? + bool insert_group_level_table(size_t, size_t, StringData) { return false; } + bool erase_group_level_table(size_t, size_t) { return false; } + bool rename_group_level_table(size_t, StringData) { return false; } + bool insert_column(size_t, DataType, StringData, bool) { return false; } + bool insert_link_column(size_t, DataType, StringData, size_t, size_t) { return false; } + bool erase_column(size_t) { return false; } + bool erase_link_column(size_t, size_t, size_t) { return false; } + bool rename_column(size_t, StringData) { return false; } + bool add_search_index(size_t) { return false; } + bool remove_search_index(size_t) { return false; } + bool add_primary_key(size_t) { return false; } + bool remove_primary_key() { return false; } + bool set_link_type(size_t, LinkType) { return false; } + + bool select_table(size_t group_level_ndx, int, const size_t*) noexcept + { + m_current_table = group_level_ndx; + return true; + } + + bool insert_empty_rows(size_t, size_t, size_t, bool) + { + // rows are only inserted at the end, so no need to do anything + return true; + } + + bool erase_rows(size_t row_ndx, size_t, size_t last_row_ndx, bool unordered) + { + for (size_t i = 0; i < m_observers.size(); ++i) { + auto& o = m_observers[i]; + if (o.table_ndx == m_current_table) { + if (o.row_ndx == row_ndx) { + invalidate(&o); + --i; + } + else if (unordered && o.row_ndx == last_row_ndx) { + o.row_ndx = row_ndx; + } + else if (!unordered && o.row_ndx > row_ndx) { + o.row_ndx -= 1; + } + } + } + return true; + } + + bool clear_table() + { + for (size_t i = 0; i < m_observers.size(); ) { + auto& o = m_observers[i]; + if (o.table_ndx == m_current_table) { + invalidate(&o); + } + else { + ++i; + } + } + return true; + } + + bool select_link_list(size_t col, size_t row) + { + m_active_linklist = nullptr; + for (auto& o : m_observers) { + if (o.table_ndx == m_current_table && o.row_ndx == row) { + m_active_linklist = &get_change(o, col); + break; + } + } + return true; + } + + void append_link_list_change(ColumnInfo::Kind kind, size_t index) { + ColumnInfo *o = m_active_linklist; + if (!o || o->kind == ColumnInfo::Kind::SetAll) { + // Active LinkList isn't observed or already has multiple kinds of changes + return; + } + + if (o->kind == ColumnInfo::Kind::None) { + o->kind = kind; + o->changed = true; + o->indices.add(index); + } + else if (o->kind == kind) { + if (kind == ColumnInfo::Kind::Remove) { + o->indices.add_shifted(index); + } + else if (kind == ColumnInfo::Kind::Insert) { + o->indices.insert_at(index); + } + else { + o->indices.add(index); + } + } + else { + // Array KVO can only send a single kind of change at a time, so + // if there's multiple just give up and send "Set" + o->indices.set(0); + o->kind = ColumnInfo::Kind::SetAll; + } + } + + bool link_list_set(size_t index, size_t) + { + append_link_list_change(ColumnInfo::Kind::Set, index); + return true; + } + + bool link_list_insert(size_t index, size_t) + { + append_link_list_change(ColumnInfo::Kind::Insert, index); + return true; + } + + bool link_list_erase(size_t index) + { + append_link_list_change(ColumnInfo::Kind::Remove, index); + return true; + } + + bool link_list_nullify(size_t index) + { + append_link_list_change(ColumnInfo::Kind::Remove, index); + return true; + } + + bool link_list_swap(size_t index1, size_t index2) + { + append_link_list_change(ColumnInfo::Kind::Set, index1); + append_link_list_change(ColumnInfo::Kind::Set, index2); + return true; + } + + bool link_list_clear(size_t old_size) + { + ColumnInfo *o = m_active_linklist; + if (!o || o->kind == ColumnInfo::Kind::SetAll) { + return true; + } + + if (o->kind == ColumnInfo::Kind::Remove) + old_size += o->indices.size(); + else if (o->kind == ColumnInfo::Kind::Insert) + old_size -= o->indices.size(); + + o->indices.set(old_size); + + o->kind = ColumnInfo::Kind::Remove; + o->changed = true; + return true; + } + + bool link_list_move(size_t from, size_t to) + { + ColumnInfo *o = m_active_linklist; + if (!o || o->kind == ColumnInfo::Kind::SetAll) { + return true; + } + if (from > to) { + std::swap(from, to); + } + + if (o->kind == ColumnInfo::Kind::None) { + o->kind = ColumnInfo::Kind::Set; + o->changed = true; + } + if (o->kind == ColumnInfo::Kind::Set) { + for (size_t i = from; i <= to; ++i) + o->indices.add(i); + } + else { + o->indices.set(0); + o->kind = ColumnInfo::Kind::SetAll; + } + return true; + } + + // Things that just mark the field as modified + bool set_int(size_t col, size_t row, int_fast64_t) { return mark_dirty(row, col); } + bool set_bool(size_t col, size_t row, bool) { return mark_dirty(row, col); } + bool set_float(size_t col, size_t row, float) { return mark_dirty(row, col); } + bool set_double(size_t col, size_t row, double) { return mark_dirty(row, col); } + bool set_string(size_t col, size_t row, StringData) { return mark_dirty(row, col); } + bool set_binary(size_t col, size_t row, BinaryData) { return mark_dirty(row, col); } + bool set_date_time(size_t col, size_t row, DateTime) { return mark_dirty(row, col); } + bool set_table(size_t col, size_t row) { return mark_dirty(row, col); } + bool set_mixed(size_t col, size_t row, const Mixed&) { return mark_dirty(row, col); } + bool set_link(size_t col, size_t row, size_t) { return mark_dirty(row, col); } + bool set_null(size_t col, size_t row) { return mark_dirty(row, col); } + bool nullify_link(size_t col, size_t row) { return mark_dirty(row, col); } + + // Doesn't change any data + bool optimize_table() { return true; } + + // Used for subtables, which we currently don't support + bool select_descriptor(int, const size_t*) { return false; } +}; +} // anonymous namespace + +namespace realm { +namespace transaction { +void advance(SharedGroup& sg, ClientHistory& history, RealmDelegate* delegate) { + TransactLogHandler(delegate, sg, [&](auto&&... args) { + LangBindHelper::advance_read(sg, history, std::move(args)...); + }); +} + +void begin(SharedGroup& sg, ClientHistory& history, RealmDelegate* delegate) { + TransactLogHandler(delegate, sg, [&](auto&&... args) { + LangBindHelper::promote_to_write(sg, history, std::move(args)...); + }); +} + +void commit(SharedGroup& sg, ClientHistory&, RealmDelegate* delegate) { + LangBindHelper::commit_and_continue_as_read(sg); + + if (delegate) { + delegate->did_change({}, {}); + } +} + +void cancel(SharedGroup& sg, ClientHistory& history, RealmDelegate* delegate) { + TransactLogHandler(delegate, sg, [&](auto&&... args) { + LangBindHelper::rollback_and_continue_as_read(sg, history, std::move(args)...); + }); +} + +} // namespace transaction +} // namespace realm diff --git a/transact_log_handler.hpp b/transact_log_handler.hpp new file mode 100644 index 00000000..3a77848f --- /dev/null +++ b/transact_log_handler.hpp @@ -0,0 +1,46 @@ +//////////////////////////////////////////////////////////////////////////// +// +// Copyright 2015 Realm Inc. +// +// 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. +// +//////////////////////////////////////////////////////////////////////////// + +#ifndef REALM_TRANSACT_LOG_HANDLER_HPP +#define REALM_TRANSACT_LOG_HANDLER_HPP + +namespace realm { +class RealmDelegate; +class SharedGroup; +class ClientHistory; + +namespace transaction { +// Advance the read transaction version, with change notifications sent to delegate +// Must not be called from within a write transaction. +void advance(SharedGroup& sg, ClientHistory& history, RealmDelegate* delegate); + +// Begin a write transaction +// If the read transaction version is not up to date, will first advance to the +// most recent read transaction and sent notifications to delegate +void begin(SharedGroup& sg, ClientHistory& history, RealmDelegate* delegate); + +// Commit a write transaction +void commit(SharedGroup& sg, ClientHistory& history, RealmDelegate* delegate); + +// Cancel a write transaction and roll back all changes, with change notifications +// for reverting to the old values sent to delegate +void cancel(SharedGroup& sg, ClientHistory& history, RealmDelegate* delegate); +} // namespace transaction +} // namespace realm + +#endif /* REALM_TRANSACT_LOG_HANDLER_HPP */