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Berkeley database handling examples: |
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|
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DB *open_db (const char *f, bool dup = false) { |
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DB *dbp = 0; |
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int r = db_create (&dbp, NULL, 0); |
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|
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if (r != 0) |
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{ |
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printf ("db_create: %s\n", db_strerror (r)); |
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exit (1); |
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} |
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|
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if (dup) |
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if (dbp->set_flags (dbp, DB_DUPSORT) != 0) |
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{ |
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cout << "Couldn't set duplicate records for database" << endl; |
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exit (1); |
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} |
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|
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if ((r = dbp->open (dbp, NULL, f, NULL, DB_BTREE, DB_CREATE, 0664)) != 0) |
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{ |
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dbp->err (dbp, r, f); |
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dbp->close (dbp, 0); |
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exit (1); |
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} |
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return dbp; |
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} |
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|
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void stor_string (DB *dbp, int32_t id, const dynstr *s) |
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{ |
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DBT dkey, data; |
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memset (&dkey, 0, sizeof (DBT)); |
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memset (&data, 0, sizeof (DBT)); |
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|
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dkey.data = &id; |
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dkey.size = sizeof (int32_t); |
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|
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data.data = s->str; |
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data.size = s->len + 1; |
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|
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int r = dbp->put (dbp, NULL, &dkey, &data, 0); |
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if (r != 0) { |
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cerr << "Database put failed: " << id << " => " << s << endl; |
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exit (1); |
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} |
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} |
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|
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void del_entry (DB *dbp, int32_t id) |
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{ |
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DBT dkey; |
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memset (&dkey, 0, sizeof (DBT)); |
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dkey.data = &id; |
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dkey.size = sizeof (int32_t); |
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dbp->del (dbp, NULL, &dkey, 0); |
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// FIXME: check returnvalue |
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} |
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|
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bool retr_string (DB *dbp, int32_t id, dynstr *&s) |
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{ |
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DBT dkey, data; |
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|
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memset (&dkey, 0, sizeof (DBT)); |
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memset (&data, 0, sizeof (DBT)); |
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|
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dkey.data = &id; |
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dkey.size = sizeof (int32_t); |
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|
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int r = dbp->get (dbp, NULL, &dkey, &data, 0); |
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if (r != DB_NOTFOUND) { |
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s = new dynstr ((char *)data.data, data.size - 1); |
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return true; |
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} |
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return false; |
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} |
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