diff options
Diffstat (limited to 'src/backend/storage/large_object/inv_api.c')
| -rw-r--r-- | src/backend/storage/large_object/inv_api.c | 27 |
1 files changed, 21 insertions, 6 deletions
diff --git a/src/backend/storage/large_object/inv_api.c b/src/backend/storage/large_object/inv_api.c index 9a2c71d5dc..9587ebc6a7 100644 --- a/src/backend/storage/large_object/inv_api.c +++ b/src/backend/storage/large_object/inv_api.c @@ -4,12 +4,20 @@ * routines for manipulating inversion fs large objects. This file * contains the user-level large object application interface routines. * + * + * Note: many of these routines leak memory in CurrentMemoryContext, as indeed + * does most of the backend code. We expect that CurrentMemoryContext will + * be a short-lived context. Data that must persist across function calls + * is kept either in CacheMemoryContext (the Relation structs) or in the + * memory context given to inv_open (for LargeObjectDesc structs). + * + * * Portions Copyright (c) 1996-2006, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/storage/large_object/inv_api.c,v 1.115 2006/03/05 15:58:38 momjian Exp $ + * $PostgreSQL: pgsql/src/backend/storage/large_object/inv_api.c,v 1.116 2006/04/26 00:34:57 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -205,14 +213,17 @@ inv_create(Oid lobjId) * inv_open -- access an existing large object. * * Returns: - * large object descriptor, appropriately filled in. + * Large object descriptor, appropriately filled in. The descriptor + * and subsidiary data are allocated in the specified memory context, + * which must be suitably long-lived for the caller's purposes. */ LargeObjectDesc * -inv_open(Oid lobjId, int flags) +inv_open(Oid lobjId, int flags, MemoryContext mcxt) { LargeObjectDesc *retval; - retval = (LargeObjectDesc *) palloc(sizeof(LargeObjectDesc)); + retval = (LargeObjectDesc *) MemoryContextAlloc(mcxt, + sizeof(LargeObjectDesc)); retval->id = lobjId; retval->subid = GetCurrentSubTransactionId(); @@ -225,9 +236,12 @@ inv_open(Oid lobjId, int flags) } else if (flags & INV_READ) { - /* be sure to copy snap into fscxt */ + /* be sure to copy snap into mcxt */ + MemoryContext oldContext = MemoryContextSwitchTo(mcxt); + retval->snapshot = CopySnapshot(ActiveSnapshot); retval->flags = IFS_RDLOCK; + MemoryContextSwitchTo(oldContext); } else elog(ERROR, "invalid flags: %d", flags); @@ -242,7 +256,8 @@ inv_open(Oid lobjId, int flags) } /* - * Closes an existing large object descriptor. + * Closes a large object descriptor previously made by inv_open(), and + * releases the long-term memory used by it. */ void inv_close(LargeObjectDesc *obj_desc) |