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Diffstat (limited to 'libodb-sqlite/odb/sqlite/connection.hxx')
| -rw-r--r-- | libodb-sqlite/odb/sqlite/connection.hxx | 356 |
1 files changed, 356 insertions, 0 deletions
diff --git a/libodb-sqlite/odb/sqlite/connection.hxx b/libodb-sqlite/odb/sqlite/connection.hxx new file mode 100644 index 0000000..dbe4494 --- /dev/null +++ b/libodb-sqlite/odb/sqlite/connection.hxx @@ -0,0 +1,356 @@ +// file : odb/sqlite/connection.hxx +// license : GNU GPL v2; see accompanying LICENSE file + +#ifndef ODB_SQLITE_CONNECTION_HXX +#define ODB_SQLITE_CONNECTION_HXX + +#include <odb/pre.hxx> + +#include <sqlite3.h> + +#include <odb/statement.hxx> +#include <odb/connection.hxx> + +#include <odb/details/mutex.hxx> +#include <odb/details/condition.hxx> +#include <odb/details/shared-ptr.hxx> +#include <odb/details/unique-ptr.hxx> + +#include <odb/sqlite/version.hxx> +#include <odb/sqlite/forward.hxx> +#include <odb/sqlite/query.hxx> +#include <odb/sqlite/tracer.hxx> +#include <odb/sqlite/transaction-impl.hxx> +#include <odb/sqlite/auto-handle.hxx> + +#include <odb/sqlite/details/export.hxx> + +namespace odb +{ + namespace sqlite + { + class statement_cache; + class generic_statement; + class connection_factory; + class attached_connection_factory; + + class connection; + typedef details::shared_ptr<connection> connection_ptr; + + // SQLite "active object", i.e., an object that needs to be + // "cleared" before the transaction can be committed and the + // connection released. These form a doubly-linked list. + // + class LIBODB_SQLITE_EXPORT active_object + { + public: + // This function may remove the object from the list since it may no + // longer be "active". + // + virtual void + clear () = 0; + + protected: + active_object (connection& c): prev_ (0), next_ (this), conn_ (c) {} + + void + list_add (); + + void + list_remove (); + + protected: + friend class connection; + + // prev_ == 0 means we are the first element. + // next_ == 0 means we are the last element. + // next_ == this means we are not on the list (prev_ should be 0). + // + active_object* prev_; + active_object* next_; + + connection& conn_; + }; + + class LIBODB_SQLITE_EXPORT connection: public odb::connection + { + public: + typedef sqlite::statement_cache statement_cache_type; + typedef sqlite::database database_type; + + // Translate the database schema in the statement text (used to + // implement attached databases). If the result is empty, then no + // translation is required and the original text should be used as is. + // + typedef void (statement_translator) (std::string& result, + const char* text, + std::size_t text_size, + connection&); + virtual + ~connection (); + + connection (connection_factory&, + int extra_flags = 0, + statement_translator* = 0); + + connection (connection_factory&, + sqlite3* handle, + statement_translator* = 0); + + // Create an attached connection (see the attached database constructor + // for details). + // + connection (attached_connection_factory&, statement_translator*); + + database_type& + database (); + + // Return the main connection of an attached connection. If this + // connection is main, return itself. + // + connection& + main_connection (); + + static connection_ptr + main_connection (const connection_ptr&); + + public: + virtual transaction_impl* + begin (); + + transaction_impl* + begin_immediate (); + + transaction_impl* + begin_exclusive (); + + public: + using odb::connection::execute; + + virtual unsigned long long + execute (const char* statement, std::size_t length); + + // Query preparation. + // + public: + template <typename T> + prepared_query<T> + prepare_query (const char* name, const char*); + + template <typename T> + prepared_query<T> + prepare_query (const char* name, const std::string&); + + template <typename T> + prepared_query<T> + prepare_query (const char* name, const sqlite::query_base&); + + template <typename T> + prepared_query<T> + prepare_query (const char* name, const odb::query_base&); + + // SQL statement tracing. + // + public: + typedef sqlite::tracer tracer_type; + + void + tracer (tracer_type& t) + { + odb::connection::tracer (t); + } + + void + tracer (tracer_type* t) + { + odb::connection::tracer (t); + } + + using odb::connection::tracer; + + public: + sqlite3* + handle (); + + statement_cache_type& + statement_cache () + { + return *statement_cache_; + } + + // Wait for the locks to be released via unlock notification. Can + // be called after getting SQLITE_LOCKED_SHAREDCACHE. + // + void + wait (); + + public: + // Reset active statements. Also invalidates query results by first + // calling invalidate_results(). + // + void + clear (); + + public: + // Note: only available on main connection. + // + generic_statement& + begin_statement (); + + generic_statement& + begin_immediate_statement (); + + generic_statement& + begin_exclusive_statement (); + + generic_statement& + commit_statement (); + + generic_statement& + rollback_statement (); + + protected: + friend class attached_connection_factory; + + connection_factory& + factory (); + + private: + connection (const connection&); + connection& operator= (const connection&); + + private: + void + init (); + + private: + // Note that we use NULL handle as an indication of an attached + // connection. + // + auto_handle<sqlite3> handle_; + + statement_translator* statement_translator_; + + // Keep statement_cache_ after handle_ so that it is destroyed before + // the connection is closed. + // + details::unique_ptr<statement_cache_type> statement_cache_; + + // Note: using odb::statement in order to break the connection-statement + // dependency cycle. + // + details::shared_ptr<odb::statement> begin_; + details::shared_ptr<odb::statement> begin_immediate_; + details::shared_ptr<odb::statement> begin_exclusive_; + details::shared_ptr<odb::statement> commit_; + details::shared_ptr<odb::statement> rollback_; + + // Unlock notification machinery. + // + private: + bool unlocked_; + details::mutex unlock_mutex_; + details::condition unlock_cond_; + + friend void + connection_unlock_callback (void**, int); + + private: + friend class statement; // statement_translator_ + friend class transaction_impl; // invalidate_results() + + // Linked list of active objects currently associated + // with this connection. + // + private: + friend class active_object; + active_object* active_objects_; + }; + + class LIBODB_SQLITE_EXPORT connection_factory: + public odb::connection_factory + { + public: + typedef sqlite::database database_type; + + virtual void + database (database_type&); + + database_type& + database () {return *db_;} + + virtual connection_ptr + connect () = 0; + + virtual + ~connection_factory (); + + connection_factory (): db_ (0) {} + + // Attach/detach additional databases. Connection is one of the main + // connections created by this factory. Note: not called for "main" and + // "temp" schemas. + // + // The default implementations simply execute the ATTACH DATABASE and + // DETACH DATABASE SQLite statements. + // + virtual void + attach_database (const connection_ptr&, + const std::string& name, + const std::string& schema); + + virtual void + detach_database (const connection_ptr&, const std::string& schema); + + // Needed to break the circular connection_factory-database dependency + // (odb::connection_factory has the odb::database member). + // + protected: + database_type* db_; + }; + + // The call to database() should cause ATTACH DATABASE (or otherwise make + // sure the database is attached). Destruction of the factory should cause + // DETACH DATABASE (or otherwise notice that this factory no longer needs + // the database attached). + // + // Note that attached_connection_factory is an active object that + // registers itself with the main connection in order to get notified on + // transaction finalization. + // + class LIBODB_SQLITE_EXPORT attached_connection_factory: + public connection_factory, + public active_object + { + public: + explicit + attached_connection_factory (const connection_ptr& main) + : active_object (*main), main_connection_ (main) {} + + virtual void + detach () = 0; + + protected: + friend class database; + friend class connection; + friend class transaction_impl; + + connection_factory& + main_factory (); + + // Note that this essentially establishes a "framework" for all the + // attached connection factory implementations: they hold a counted + // reference to the main connection and they maintain a single shared + // attached connection. + // + connection_ptr main_connection_; + connection_ptr attached_connection_; + }; + } +} + +#include <odb/sqlite/connection.ixx> + +#include <odb/post.hxx> + +#endif // ODB_SQLITE_CONNECTION_HXX |