/*- * See the file LICENSE for redistribution information. * * Copyright (c) 1997, 2011 Oracle and/or its affiliates. All rights reserved. * * $Id$ */ #include #include #include #include #include #ifdef _WIN32 extern "C" { extern int getopt(int, char * const *, const char *); extern int optind; } #else #include #endif #include #define DATABASE "sequence.db" #define SEQUENCE "my_sequence" using std::cout; using std::cerr; class SequenceExample { public: SequenceExample(); void run(bool removeExistingDatabase, const char *fileName); private: // no need for copy and assignment SequenceExample(const SequenceExample &); void operator = (const SequenceExample &); }; int usage() { (void)fprintf(stderr, "usage: SequenceExample [-r] [database]\n"); return (EXIT_FAILURE); } int main(int argc, char *argv[]) { int ch, rflag; const char *database; rflag = 0; while ((ch = getopt(argc, argv, "r")) != EOF) switch (ch) { case 'r': rflag = 1; break; case '?': default: return (usage()); } argc -= optind; argv += optind; /* Accept optional database name. */ database = *argv == NULL ? DATABASE : argv[0]; // Use a try block just to report any errors. // An alternate approach to using exceptions is to // use error models (see DbEnv::set_error_model()) so // that error codes are returned for all Berkeley DB methods. // try { SequenceExample app; app.run((bool)(rflag == 1 ? true : false), database); return (EXIT_SUCCESS); } catch (DbException &dbe) { cerr << "SequenceExample: " << dbe.what() << "\n"; return (EXIT_FAILURE); } } SequenceExample::SequenceExample() { } void SequenceExample::run(bool removeExistingDatabase, const char *fileName) { // Remove the previous database. if (removeExistingDatabase) (void)remove(fileName); // Create the database object. // There is no environment for this simple example. Db db(0, 0); db.set_error_stream(&cerr); db.set_errpfx("SequenceExample"); db.open(NULL, fileName, NULL, DB_BTREE, DB_CREATE, 0664); // We put a try block around this section of code // to ensure that our database is properly closed // in the event of an error. // try { Dbt key((void *)SEQUENCE, (u_int32_t)strlen(SEQUENCE)); DbSequence seq(&db, 0); seq.open(0, &key, DB_CREATE); for (int i = 0; i < 10; i++) { db_seq_t seqnum; seq.get(0, 1, &seqnum, 0); // We don't have a portable way to print 64-bit numbers. cout << "Got sequence number (" << (int)(seqnum >> 32) << ", " << (unsigned)seqnum << ")\n"; } seq.close(0); } catch (DbException &dbe) { cerr << "SequenceExample: " << dbe.what() << "\n"; } db.close(0); }