/*- * See the file LICENSE for redistribution information. * * Copyright (c) 1997,2008 Oracle. All rights reserved. * * $Id: cxx_db.cpp,v 12.22 2008/01/08 20:58:09 bostic Exp $ */ #include "db_config.h" #include "db_int.h" #include "db_cxx.h" #include "dbinc/cxx_int.h" #include "dbinc/db_page.h" #include "dbinc_auto/db_auto.h" #include "dbinc_auto/crdel_auto.h" #include "dbinc/db_dispatch.h" #include "dbinc_auto/db_ext.h" #include "dbinc_auto/common_ext.h" // Helper macros for simple methods that pass through to the // underlying C method. It may return an error or raise an exception. // Note this macro expects that input _argspec is an argument // list element (e.g., "char *arg") and that _arglist is the arguments // that should be passed through to the C method (e.g., "(db, arg)") // #define DB_METHOD(_name, _argspec, _arglist, _retok) \ int Db::_name _argspec \ { \ int ret; \ DB *db = unwrap(this); \ \ ret = db->_name _arglist; \ if (!_retok(ret)) \ DB_ERROR(dbenv_, "Db::" # _name, ret, error_policy()); \ return (ret); \ } #define DB_DESTRUCTOR(_name, _argspec, _arglist, _retok) \ int Db::_name _argspec \ { \ int ret; \ DB *db = unwrap(this); \ \ if (!db) { \ DB_ERROR(dbenv_, "Db::" # _name, EINVAL, error_policy()); \ return (EINVAL); \ } \ ret = db->_name _arglist; \ cleanup(); \ if (!_retok(ret)) \ DB_ERROR(dbenv_, "Db::" # _name, ret, error_policy()); \ return (ret); \ } #define DB_METHOD_QUIET(_name, _argspec, _arglist) \ int Db::_name _argspec \ { \ DB *db = unwrap(this); \ \ return (db->_name _arglist); \ } #define DB_METHOD_VOID(_name, _argspec, _arglist) \ void Db::_name _argspec \ { \ DB *db = unwrap(this); \ \ db->_name _arglist; \ } // A truism for the Db object is that there is a valid // DB handle from the constructor until close(). // After the close, the DB handle is invalid and // no operations are permitted on the Db (other than // destructor). Leaving the Db handle open and not // doing a close is generally considered an error. // // We used to allow Db objects to be closed and reopened. // This implied always keeping a valid DB object, and // coordinating the open objects between Db/DbEnv turned // out to be overly complicated. Now we do not allow this. Db::Db(DbEnv *dbenv, u_int32_t flags) : imp_(0) , dbenv_(dbenv) , mpf_(0) , construct_error_(0) , flags_(0) , construct_flags_(flags) , append_recno_callback_(0) , associate_callback_(0) , bt_compare_callback_(0) , bt_prefix_callback_(0) , dup_compare_callback_(0) , feedback_callback_(0) , h_compare_callback_(0) , h_hash_callback_(0) { if (dbenv_ == 0) flags_ |= DB_CXX_PRIVATE_ENV; if ((construct_error_ = initialize()) != 0) DB_ERROR(dbenv_, "Db::Db", construct_error_, error_policy()); } // If the DB handle is still open, we close it. This is to make stack // allocation of Db objects easier so that they are cleaned up in the error // path. If the environment was closed prior to this, it may cause a trap, but // an error message is generated during the environment close. Applications // should call close explicitly in normal (non-exceptional) cases to check the // return value. // Db::~Db() { DB *db; db = unwrap(this); if (db != NULL) { (void)db->close(db, 0); cleanup(); } } // private method to initialize during constructor. // initialize must create a backing DB object, // and if that creates a new DB_ENV, it must be tied to a new DbEnv. // int Db::initialize() { DB *db; DB_ENV *cenv = unwrap(dbenv_); int ret; u_int32_t cxx_flags; cxx_flags = construct_flags_ & DB_CXX_NO_EXCEPTIONS; // Create a new underlying DB object. // We rely on the fact that if a NULL DB_ENV* is given, // one is allocated by DB. // if ((ret = db_create(&db, cenv, construct_flags_ & ~cxx_flags)) != 0) return (ret); // Associate the DB with this object imp_ = db; db->api_internal = this; // Create a new DbEnv from a DB_ENV* if it was created locally. // It is deleted in Db::close(). // if ((flags_ & DB_CXX_PRIVATE_ENV) != 0) dbenv_ = new DbEnv(db->dbenv, cxx_flags); // Create a DbMpoolFile from the DB_MPOOLFILE* in the DB handle. mpf_ = new DbMpoolFile(); mpf_->imp_ = db->mpf; return (0); } // private method to cleanup after destructor or during close. // If the environment was created by this Db object, we need to delete it. // void Db::cleanup() { if (imp_ != 0) { imp_ = 0; // we must dispose of the DbEnv object if // we created it. This will be the case // if a NULL DbEnv was passed into the constructor. // The underlying DB_ENV object will be inaccessible // after the close, so we must clean it up now. // if ((flags_ & DB_CXX_PRIVATE_ENV) != 0) { dbenv_->cleanup(); delete dbenv_; dbenv_ = 0; } delete mpf_; } } // Return a tristate value corresponding to whether we should // throw exceptions on errors: // ON_ERROR_RETURN // ON_ERROR_THROW // ON_ERROR_UNKNOWN // int Db::error_policy() { if (dbenv_ != NULL) return (dbenv_->error_policy()); else { // If the dbenv_ is null, that means that the user // did not attach an environment, so the correct error // policy can be deduced from constructor flags // for this Db. // if ((construct_flags_ & DB_CXX_NO_EXCEPTIONS) != 0) { return (ON_ERROR_RETURN); } else { return (ON_ERROR_THROW); } } } DB_DESTRUCTOR(close, (u_int32_t flags), (db, flags), DB_RETOK_STD) DB_METHOD(compact, (DbTxn *txnid, Dbt *start, Dbt *stop, DB_COMPACT *c_data, u_int32_t flags, Dbt *end), (db, unwrap(txnid), start, stop, c_data, flags, end), DB_RETOK_STD) // The following cast implies that Dbc can be no larger than DBC DB_METHOD(cursor, (DbTxn *txnid, Dbc **cursorp, u_int32_t flags), (db, unwrap(txnid), (DBC **)cursorp, flags), DB_RETOK_STD) DB_METHOD(del, (DbTxn *txnid, Dbt *key, u_int32_t flags), (db, unwrap(txnid), key, flags), DB_RETOK_DBDEL) void Db::err(int error, const char *format, ...) { DB *db = unwrap(this); DB_REAL_ERR(db->dbenv, error, DB_ERROR_SET, 1, format); } void Db::errx(const char *format, ...) { DB *db = unwrap(this); DB_REAL_ERR(db->dbenv, 0, DB_ERROR_NOT_SET, 1, format); } DB_METHOD(exists, (DbTxn *txnid, Dbt *key, u_int32_t flags), (db, unwrap(txnid), key, flags), DB_RETOK_EXISTS) DB_METHOD(fd, (int *fdp), (db, fdp), DB_RETOK_STD) int Db::get(DbTxn *txnid, Dbt *key, Dbt *value, u_int32_t flags) { DB *db = unwrap(this); int ret; ret = db->get(db, unwrap(txnid), key, value, flags); if (!DB_RETOK_DBGET(ret)) { if (ret == DB_BUFFER_SMALL) DB_ERROR_DBT(dbenv_, "Db::get", value, error_policy()); else DB_ERROR(dbenv_, "Db::get", ret, error_policy()); } return (ret); } int Db::get_byteswapped(int *isswapped) { DB *db = (DB *)unwrapConst(this); return (db->get_byteswapped(db, isswapped)); } DbEnv *Db::get_env() { DB *db = (DB *)unwrapConst(this); DB_ENV *dbenv = db->get_env(db); return (dbenv != NULL ? DbEnv::get_DbEnv(dbenv) : NULL); } DbMpoolFile *Db::get_mpf() { return (mpf_); } DB_METHOD(get_dbname, (const char **filenamep, const char **dbnamep), (db, filenamep, dbnamep), DB_RETOK_STD) DB_METHOD(get_open_flags, (u_int32_t *flagsp), (db, flagsp), DB_RETOK_STD) int Db::get_type(DBTYPE *dbtype) { DB *db = (DB *)unwrapConst(this); return (db->get_type(db, dbtype)); } // Dbc is a "compatible" subclass of DBC - that is, no virtual functions // or even extra data members, so these casts, although technically // non-portable, "should" always be okay. DB_METHOD(join, (Dbc **curslist, Dbc **cursorp, u_int32_t flags), (db, (DBC **)curslist, (DBC **)cursorp, flags), DB_RETOK_STD) DB_METHOD(key_range, (DbTxn *txnid, Dbt *key, DB_KEY_RANGE *results, u_int32_t flags), (db, unwrap(txnid), key, results, flags), DB_RETOK_STD) // If an error occurred during the constructor, report it now. // Otherwise, call the underlying DB->open method. // int Db::open(DbTxn *txnid, const char *file, const char *database, DBTYPE type, u_int32_t flags, int mode) { int ret; DB *db = unwrap(this); if (construct_error_ != 0) ret = construct_error_; else ret = db->open(db, unwrap(txnid), file, database, type, flags, mode); if (!DB_RETOK_STD(ret)) DB_ERROR(dbenv_, "Db::open", ret, error_policy()); return (ret); } int Db::pget(DbTxn *txnid, Dbt *key, Dbt *pkey, Dbt *value, u_int32_t flags) { DB *db = unwrap(this); int ret; ret = db->pget(db, unwrap(txnid), key, pkey, value, flags); /* The logic here is identical to Db::get - reuse the macro. */ if (!DB_RETOK_DBGET(ret)) { if (ret == DB_BUFFER_SMALL && DB_OVERFLOWED_DBT(value)) DB_ERROR_DBT(dbenv_, "Db::pget", value, error_policy()); else DB_ERROR(dbenv_, "Db::pget", ret, error_policy()); } return (ret); } DB_METHOD(put, (DbTxn *txnid, Dbt *key, Dbt *value, u_int32_t flags), (db, unwrap(txnid), key, value, flags), DB_RETOK_DBPUT) DB_DESTRUCTOR(rename, (const char *file, const char *database, const char *newname, u_int32_t flags), (db, file, database, newname, flags), DB_RETOK_STD) DB_DESTRUCTOR(remove, (const char *file, const char *database, u_int32_t flags), (db, file, database, flags), DB_RETOK_STD) DB_METHOD(truncate, (DbTxn *txnid, u_int32_t *countp, u_int32_t flags), (db, unwrap(txnid), countp, flags), DB_RETOK_STD) DB_METHOD(stat, (DbTxn *txnid, void *sp, u_int32_t flags), (db, unwrap(txnid), sp, flags), DB_RETOK_STD) DB_METHOD(stat_print, (u_int32_t flags), (db, flags), DB_RETOK_STD) DB_METHOD(sync, (u_int32_t flags), (db, flags), DB_RETOK_STD) DB_METHOD(upgrade, (const char *name, u_int32_t flags), (db, name, flags), DB_RETOK_STD) //////////////////////////////////////////////////////////////////////// // // callbacks // // *_intercept_c are 'glue' functions that must be declared // as extern "C" so to be typesafe. Using a C++ method, even // a static class method with 'correct' arguments, will not pass // the test; some picky compilers do not allow mixing of function // pointers to 'C' functions with function pointers to C++ functions. // // One wart with this scheme is that the *_callback_ method pointer // must be declared public to be accessible by the C intercept. // It's possible to accomplish the goal without this, and with // another public transfer method, but it's just too much overhead. // These callbacks are supposed to be *fast*. // // The DBTs we receive in these callbacks from the C layer may be // manufactured there, but we want to treat them as a Dbts. // Technically speaking, these DBTs were not constructed as a Dbts, // but it should be safe to cast them as such given that Dbt is a // *very* thin extension of the DBT. That is, Dbt has no additional // data elements, does not use virtual functions, virtual inheritance, // multiple inheritance, RTI, or any other language feature that // causes the structure to grow or be displaced. Although this may // sound risky, a design goal of C++ is complete structure // compatibility with C, and has the philosophy 'if you don't use it, // you shouldn't incur the overhead'. If the C/C++ compilers you're // using on a given machine do not have matching struct layouts, then // a lot more things will be broken than just this. // // The alternative, creating a Dbt here in the callback, and populating // it from the DBT, is just too slow and cumbersome to be very useful. // These macros avoid a lot of boilerplate code for callbacks #define DB_CALLBACK_C_INTERCEPT(_name, _rettype, _cargspec, \ _return, _cxxargs) \ extern "C" _rettype _db_##_name##_intercept_c _cargspec \ { \ Db *cxxthis; \ \ /* We don't have a dbenv handle at this point. */ \ DB_ASSERT(NULL, cthis != NULL); \ cxxthis = Db::get_Db(cthis); \ DB_ASSERT(cthis->dbenv->env, cxxthis != NULL); \ DB_ASSERT(cthis->dbenv->env, cxxthis->_name##_callback_ != 0); \ \ _return (*cxxthis->_name##_callback_) _cxxargs; \ } #define DB_SET_CALLBACK(_cxxname, _name, _cxxargspec, _cb) \ int Db::_cxxname _cxxargspec \ { \ DB *cthis = unwrap(this); \ \ _name##_callback_ = _cb; \ return ((*(cthis->_cxxname))(cthis, \ (_cb) ? _db_##_name##_intercept_c : NULL)); \ } /* associate callback - doesn't quite fit the pattern because of the flags */ DB_CALLBACK_C_INTERCEPT(associate, int, (DB *cthis, const DBT *key, const DBT *data, DBT *retval), return, (cxxthis, Dbt::get_const_Dbt(key), Dbt::get_const_Dbt(data), Dbt::get_Dbt(retval))) int Db::associate(DbTxn *txn, Db *secondary, int (*callback)(Db *, const Dbt *, const Dbt *, Dbt *), u_int32_t flags) { DB *cthis = unwrap(this); /* Since the secondary Db is used as the first argument * to the callback, we store the C++ callback on it * rather than on 'this'. */ secondary->associate_callback_ = callback; return ((*(cthis->associate))(cthis, unwrap(txn), unwrap(secondary), (callback) ? _db_associate_intercept_c : NULL, flags)); } DB_CALLBACK_C_INTERCEPT(feedback, void, (DB *cthis, int opcode, int pct), /* no return */ (void), (cxxthis, opcode, pct)) DB_SET_CALLBACK(set_feedback, feedback, (void (*arg)(Db *cxxthis, int opcode, int pct)), arg) DB_CALLBACK_C_INTERCEPT(append_recno, int, (DB *cthis, DBT *data, db_recno_t recno), return, (cxxthis, Dbt::get_Dbt(data), recno)) DB_SET_CALLBACK(set_append_recno, append_recno, (int (*arg)(Db *cxxthis, Dbt *data, db_recno_t recno)), arg) DB_CALLBACK_C_INTERCEPT(bt_compare, int, (DB *cthis, const DBT *data1, const DBT *data2), return, (cxxthis, Dbt::get_const_Dbt(data1), Dbt::get_const_Dbt(data2))) DB_SET_CALLBACK(set_bt_compare, bt_compare, (int (*arg)(Db *cxxthis, const Dbt *data1, const Dbt *data2)), arg) DB_CALLBACK_C_INTERCEPT(bt_prefix, size_t, (DB *cthis, const DBT *data1, const DBT *data2), return, (cxxthis, Dbt::get_const_Dbt(data1), Dbt::get_const_Dbt(data2))) DB_SET_CALLBACK(set_bt_prefix, bt_prefix, (size_t (*arg)(Db *cxxthis, const Dbt *data1, const Dbt *data2)), arg) DB_CALLBACK_C_INTERCEPT(dup_compare, int, (DB *cthis, const DBT *data1, const DBT *data2), return, (cxxthis, Dbt::get_const_Dbt(data1), Dbt::get_const_Dbt(data2))) DB_SET_CALLBACK(set_dup_compare, dup_compare, (int (*arg)(Db *cxxthis, const Dbt *data1, const Dbt *data2)), arg) DB_CALLBACK_C_INTERCEPT(h_compare, int, (DB *cthis, const DBT *data1, const DBT *data2), return, (cxxthis, Dbt::get_const_Dbt(data1), Dbt::get_const_Dbt(data2))) DB_SET_CALLBACK(set_h_compare, h_compare, (int (*arg)(Db *cxxthis, const Dbt *data1, const Dbt *data2)), arg) DB_CALLBACK_C_INTERCEPT(h_hash, u_int32_t, (DB *cthis, const void *data, u_int32_t len), return, (cxxthis, data, len)) DB_SET_CALLBACK(set_h_hash, h_hash, (u_int32_t (*arg)(Db *cxxthis, const void *data, u_int32_t len)), arg) // This is a 'glue' function declared as extern "C" so it will // be compatible with picky compilers that do not allow mixing // of function pointers to 'C' functions with function pointers // to C++ functions. // extern "C" int _verify_callback_c(void *handle, const void *str_arg) { char *str; __DB_STD(ostream) *out; str = (char *)str_arg; out = (__DB_STD(ostream) *)handle; (*out) << str; if (out->fail()) return (EIO); return (0); } int Db::verify(const char *name, const char *subdb, __DB_STD(ostream) *ostr, u_int32_t flags) { DB *db = unwrap(this); int ret; if (!db) ret = EINVAL; else { ret = __db_verify_internal(db, name, subdb, ostr, _verify_callback_c, flags); // After a DB->verify (no matter if success or failure), // the underlying DB object must not be accessed. // cleanup(); } if (!DB_RETOK_STD(ret)) DB_ERROR(dbenv_, "Db::verify", ret, error_policy()); return (ret); } DB_METHOD(set_bt_compare, (bt_compare_fcn_type func), (db, func), DB_RETOK_STD) DB_METHOD(get_bt_minkey, (u_int32_t *bt_minkeyp), (db, bt_minkeyp), DB_RETOK_STD) DB_METHOD(set_bt_minkey, (u_int32_t bt_minkey), (db, bt_minkey), DB_RETOK_STD) DB_METHOD(set_bt_prefix, (bt_prefix_fcn_type func), (db, func), DB_RETOK_STD) DB_METHOD(set_dup_compare, (dup_compare_fcn_type func), (db, func), DB_RETOK_STD) DB_METHOD(get_encrypt_flags, (u_int32_t *flagsp), (db, flagsp), DB_RETOK_STD) DB_METHOD(set_encrypt, (const char *passwd, u_int32_t flags), (db, passwd, flags), DB_RETOK_STD) DB_METHOD_VOID(get_errfile, (FILE **errfilep), (db, errfilep)) DB_METHOD_VOID(set_errfile, (FILE *errfile), (db, errfile)) DB_METHOD_VOID(get_errpfx, (const char **errpfx), (db, errpfx)) DB_METHOD_VOID(set_errpfx, (const char *errpfx), (db, errpfx)) DB_METHOD(get_flags, (u_int32_t *flagsp), (db, flagsp), DB_RETOK_STD) DB_METHOD(set_flags, (u_int32_t flags), (db, flags), DB_RETOK_STD) DB_METHOD(set_h_compare, (h_compare_fcn_type func), (db, func), DB_RETOK_STD) DB_METHOD(get_h_ffactor, (u_int32_t *h_ffactorp), (db, h_ffactorp), DB_RETOK_STD) DB_METHOD(set_h_ffactor, (u_int32_t h_ffactor), (db, h_ffactor), DB_RETOK_STD) DB_METHOD(set_h_hash, (h_hash_fcn_type func), (db, func), DB_RETOK_STD) DB_METHOD(get_h_nelem, (u_int32_t *h_nelemp), (db, h_nelemp), DB_RETOK_STD) DB_METHOD(set_h_nelem, (u_int32_t h_nelem), (db, h_nelem), DB_RETOK_STD) DB_METHOD(get_lorder, (int *db_lorderp), (db, db_lorderp), DB_RETOK_STD) DB_METHOD(set_lorder, (int db_lorder), (db, db_lorder), DB_RETOK_STD) DB_METHOD_VOID(get_msgfile, (FILE **msgfilep), (db, msgfilep)) DB_METHOD_VOID(set_msgfile, (FILE *msgfile), (db, msgfile)) DB_METHOD_QUIET(get_multiple, (), (db)) DB_METHOD(get_pagesize, (u_int32_t *db_pagesizep), (db, db_pagesizep), DB_RETOK_STD) DB_METHOD(set_pagesize, (u_int32_t db_pagesize), (db, db_pagesize), DB_RETOK_STD) DB_METHOD(get_priority, (DB_CACHE_PRIORITY *priorityp), (db, priorityp), DB_RETOK_STD) DB_METHOD(set_priority, (DB_CACHE_PRIORITY priority), (db, priority), DB_RETOK_STD) DB_METHOD(get_re_delim, (int *re_delimp), (db, re_delimp), DB_RETOK_STD) DB_METHOD(set_re_delim, (int re_delim), (db, re_delim), DB_RETOK_STD) DB_METHOD(get_re_len, (u_int32_t *re_lenp), (db, re_lenp), DB_RETOK_STD) DB_METHOD(set_re_len, (u_int32_t re_len), (db, re_len), DB_RETOK_STD) DB_METHOD(get_re_pad, (int *re_padp), (db, re_padp), DB_RETOK_STD) DB_METHOD(set_re_pad, (int re_pad), (db, re_pad), DB_RETOK_STD) DB_METHOD(get_re_source, (const char **re_source), (db, re_source), DB_RETOK_STD) DB_METHOD(set_re_source, (const char *re_source), (db, re_source), DB_RETOK_STD) DB_METHOD(get_q_extentsize, (u_int32_t *extentsizep), (db, extentsizep), DB_RETOK_STD) DB_METHOD(set_q_extentsize, (u_int32_t extentsize), (db, extentsize), DB_RETOK_STD) DB_METHOD_QUIET(set_alloc, (db_malloc_fcn_type malloc_fcn, db_realloc_fcn_type realloc_fcn, db_free_fcn_type free_fcn), (db, malloc_fcn, realloc_fcn, free_fcn)) void Db::set_errcall(void (*arg)(const DbEnv *, const char *, const char *)) { dbenv_->set_errcall(arg); } void Db::set_msgcall(void (*arg)(const DbEnv *, const char *)) { dbenv_->set_msgcall(arg); } void *Db::get_app_private() const { return unwrapConst(this)->app_private; } void Db::set_app_private(void *value) { unwrap(this)->app_private = value; } DB_METHOD(get_cachesize, (u_int32_t *gbytesp, u_int32_t *bytesp, int *ncachep), (db, gbytesp, bytesp, ncachep), DB_RETOK_STD) DB_METHOD(set_cachesize, (u_int32_t gbytes, u_int32_t bytes, int ncache), (db, gbytes, bytes, ncache), DB_RETOK_STD) int Db::set_paniccall(void (*callback)(DbEnv *, int)) { return (dbenv_->set_paniccall(callback)); } __DB_STD(ostream) *Db::get_error_stream() { return dbenv_->get_error_stream(); } void Db::set_error_stream(__DB_STD(ostream) *error_stream) { dbenv_->set_error_stream(error_stream); } __DB_STD(ostream) *Db::get_message_stream() { return dbenv_->get_message_stream(); } void Db::set_message_stream(__DB_STD(ostream) *message_stream) { dbenv_->set_message_stream(message_stream); } DB_METHOD_QUIET(get_transactional, (), (db))