diff options
Diffstat (limited to 'src/backend/utils/misc/database.c')
| -rw-r--r-- | src/backend/utils/misc/database.c | 71 |
1 files changed, 23 insertions, 48 deletions
diff --git a/src/backend/utils/misc/database.c b/src/backend/utils/misc/database.c index 321ab943aea..f5ff732b8f2 100644 --- a/src/backend/utils/misc/database.c +++ b/src/backend/utils/misc/database.c @@ -1,13 +1,13 @@ /*------------------------------------------------------------------------- * * database.c - * miscellanious initialization support stuff + * miscellaneous initialization support stuff * * Copyright (c) 1994, Regents of the University of California * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/utils/misc/Attic/database.c,v 1.29 1999/09/18 19:08:07 tgl Exp $ + * $Header: /cvsroot/pgsql/src/backend/utils/misc/Attic/database.c,v 1.30 1999/09/24 00:25:04 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -21,10 +21,6 @@ #include "miscadmin.h" #include "utils/syscache.h" -#ifdef MULTIBYTE -#include "mb/pg_wchar.h" -#endif - #ifdef NOT_USED /* GetDatabaseInfo() * Pull database information from pg_database. @@ -153,24 +149,13 @@ ExpandDatabasePath(char *dbpath) * cache. To get around this problem, this code opens and scans the * pg_database relation by hand. * - * This algorithm relies on the fact that first attribute in the - * pg_database relation schema is the database name. It also knows - * about the internal format of tuples on disk and the length of - * the datname attribute. It knows the location of the pg_database - * file. - * Actually, the code looks as though it is using the pg_database - * tuple definition to locate the database name, so the above statement - * seems to be no longer correct. - thomas 1997-11-01 - * - * This code is called from InitPostgres(), before we chdir() to the - * local database directory and before we open any relations. - * Used to be called after the chdir(), but we now want to confirm - * the location of the target database using pg_database info. - * - thomas 1997-11-01 + * This code knows way more than it should about the layout of + * tuples on disk, but there seems to be no help for that. + * We're pulling ourselves up by the bootstraps here... * -------------------------------- */ void -GetRawDatabaseInfo(char *name, int4 *owner, Oid *db_id, char *path, int *encoding) +GetRawDatabaseInfo(char *name, Oid *db_id, char *path) { int dbfd; int fileflags; @@ -238,48 +223,38 @@ GetRawDatabaseInfo(char *name, int4 *owner, Oid *db_id, char *path, int *encodin * skip this tuple. XXX warning, will robinson: violation of * transaction semantics happens right here. we should check * to be sure that the xact that deleted this tuple actually - * committed. only way to do this at init time is to paw over - * the log relation by hand, too. let's be optimistic. + * committed. Only way to do that at init time is to paw over + * the log relation by hand, too. Instead we take the + * conservative assumption that if someone tried to delete it, + * it's gone. The other side of the coin is that we might + * accept a tuple that was stored and never committed. All in + * all, this code is pretty shaky. We will cross-check our + * result in ReverifyMyDatabase() in postinit.c. * - * XXX This is an evil type cast. tup->t_xmax is char[5] while - * TransactionId is struct * { char data[5] }. It works but - * if data is ever moved and no longer the first field this - * will be broken!! -mer 11 Nov 1991. + * NOTE: if a bogus tuple in pg_database prevents connection + * to a valid database, a fix is to connect to another database + * and do "select * from pg_database". That should cause + * committed and dead tuples to be marked with correct states. + * + * XXX wouldn't it be better to let new backends read the + * database OID from a flat file, handled the same way + * we handle the password relation? */ if (TransactionIdIsValid((TransactionId) tup.t_data->t_xmax)) continue; /* - * Okay, see if this is the one we want. XXX 1 july 91: mao - * and mer discover that tuples now squash t_bits. Why is - * this? - * - * 24 july 92: mer realizes that the t_bits field is only used - * in the event of null values. If no fields are null we - * reduce the header size by doing the squash. t_hoff tells - * you exactly how big the header actually is. use the PC - * means of getting at sys cat attrs. + * Okay, see if this is the one we want. */ tup_db = (Form_pg_database) GETSTRUCT(&tup); -#ifdef MULTIBYTE - /* - * get encoding from template database. This is the "default - * for default" for create database command. - */ - if (strcmp("template1", tup_db->datname.data) == 0) - SetTemplateEncoding(tup_db->encoding); -#endif if (strcmp(name, tup_db->datname.data) == 0) { + /* Found it; extract the OID and the database path. */ *db_id = tup.t_data->t_oid; strncpy(path, VARDATA(&(tup_db->datpath)), (VARSIZE(&(tup_db->datpath)) - VARHDRSZ)); *(path + VARSIZE(&(tup_db->datpath)) - VARHDRSZ) = '\0'; -#ifdef MULTIBYTE - *encoding = tup_db->encoding; -#endif - goto done; } } |