diff options
Diffstat (limited to 'src/backend/storage/large_object/inv_api.c')
| -rw-r--r-- | src/backend/storage/large_object/inv_api.c | 54 |
1 files changed, 50 insertions, 4 deletions
diff --git a/src/backend/storage/large_object/inv_api.c b/src/backend/storage/large_object/inv_api.c index c3d63ac36b2..e92c75f0a34 100644 --- a/src/backend/storage/large_object/inv_api.c +++ b/src/backend/storage/large_object/inv_api.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/storage/large_object/inv_api.c,v 1.30 1998/06/15 19:29:16 momjian Exp $ + * $Header: /cvsroot/pgsql/src/backend/storage/large_object/inv_api.c,v 1.31 1998/07/21 04:17:24 momjian Exp $ * *------------------------------------------------------------------------- */ @@ -60,6 +60,19 @@ * for data. */ +/* + * In order to prevent buffer leak on transaction commit, large object + * scan index handling has been modified. Indexes are persistant inside + * a transaction but may be closed between two calls to this API (when + * transaction is committed while object is opened, or when no + * transaction is active). Scan indexes are thus now reinitialized using + * the object current offset. [PA] + * + * Some cleanup has been also done for non freed memory. + * + * For subsequent notes, [PA] is Pascal André <andre@via.ecp.fr> + */ + #define IFREESPC(p) (PageGetFreeSpace(p) - sizeof(HeapTupleData) - sizeof(struct varlena) - sizeof(int32)) #define IMAXBLK 8092 #define IMINBLK 512 @@ -261,8 +274,11 @@ inv_close(LargeObjectDesc *obj_desc) { Assert(PointerIsValid(obj_desc)); - if (obj_desc->iscan != (IndexScanDesc) NULL) + if (obj_desc->iscan != (IndexScanDesc) NULL) { index_endscan(obj_desc->iscan); + pfree(obj_desc->iscan); + obj_desc->iscan = NULL; + } heap_close(obj_desc->heap_r); index_close(obj_desc->index_r); @@ -547,6 +563,28 @@ inv_write(LargeObjectDesc *obj_desc, char *buf, int nbytes) } /* + * inv_cleanindex -- + * Clean opened indexes for large objects, and clears current result. + * This is necessary on transaction commit in order to prevent buffer + * leak. + * This function must be called for each opened large object. + * [ PA, 7/17/98 ] + */ +void +inv_cleanindex(LargeObjectDesc *obj_desc) +{ + Assert(PointerIsValid(obj_desc)); + + if (obj_desc->iscan == (IndexScanDesc) NULL) return; + + index_endscan(obj_desc->iscan); + pfree(obj_desc->iscan); + obj_desc->iscan = (IndexScanDesc) NULL; + + ItemPointerSetInvalid(&(obj_desc->htid)); +} + +/* * inv_fetchtup -- Fetch an inversion file system block. * * This routine finds the file system block containing the offset @@ -591,8 +629,13 @@ inv_fetchtup(LargeObjectDesc *obj_desc, Buffer *bufP) { ScanKeyData skey; + /* + * As scan index may be prematurely closed (on commit), + * we must use object current offset (was 0) to + * reinitialize the entry [ PA ]. + */ ScanKeyEntryInitialize(&skey, 0x0, 1, F_INT4GE, - Int32GetDatum(0)); + Int32GetDatum(obj_desc->offset)); obj_desc->iscan = index_beginscan(obj_desc->index_r, (bool) 0, (uint16) 1, @@ -622,7 +665,7 @@ inv_fetchtup(LargeObjectDesc *obj_desc, Buffer *bufP) /* remember this tid -- we may need it for later reads/writes */ ItemPointerCopy(&(res->heap_iptr), &(obj_desc->htid)); - + pfree(res); } else { @@ -1179,6 +1222,7 @@ _inv_getsize(Relation hreln, TupleDesc hdesc, Relation ireln) if (res == (RetrieveIndexResult) NULL) { index_endscan(iscan); + pfree(iscan); return (0); } @@ -1192,11 +1236,13 @@ _inv_getsize(Relation hreln, TupleDesc hdesc, Relation ireln) ReleaseBuffer(buf); htup = heap_fetch(hreln, false, &(res->heap_iptr), &buf); + pfree(res); } while (!HeapTupleIsValid(htup)); /* don't need the index scan anymore */ index_endscan(iscan); + pfree(iscan); /* get olastbyte attribute */ d = heap_getattr(htup, 1, hdesc, &isNull); |