Minor code cleanups, make in_group() check faster.

diff --git a/src/backend/catalog/aclchk.c b/src/backend/catalog/aclchk.c
index a338cfb2242f1a7720411a6108be0040c367b2ae..b7013d28824d0df09ec958ba3dcc237a0e9e8dde 100644 (file)
--- a/src/backend/catalog/aclchk.c
+++ b/src/backend/catalog/aclchk.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *   $Header: /cvsroot/pgsql/src/backend/catalog/aclchk.c,v 1.41 2000/10/02 04:49:28 tgl Exp $
+ *   $Header: /cvsroot/pgsql/src/backend/catalog/aclchk.c,v 1.42 2000/11/03 19:02:18 tgl Exp $
  *
  * NOTES
  *   See acl.h.
@@ -185,41 +185,40 @@ get_groname(AclId grosysid)
 static bool
 in_group(AclId uid, AclId gid)
 {
-   Relation    relation;
    HeapTuple   tuple;
-   Acl        *tmp;
+   Datum       att;
+   bool        isNull;
+   IdList     *tmp;
+   AclId      *aidp;
    int         i,
                num;
-   AclId      *aidp;
-   bool        found = false;
 
-   relation = heap_openr(GroupRelationName, RowExclusiveLock);
    tuple = SearchSysCacheTuple(GROSYSID,
                                ObjectIdGetDatum(gid),
                                0, 0, 0);
-   if (HeapTupleIsValid(tuple) &&
-       !heap_attisnull(tuple, Anum_pg_group_grolist))
+   if (HeapTupleIsValid(tuple))
    {
-       tmp = (IdList *) heap_getattr(tuple,
-                                     Anum_pg_group_grolist,
-                                     RelationGetDescr(relation),
-                                     (bool *) NULL);
-       /* be sure the IdList is not toasted */
-       tmp = DatumGetIdListP(PointerGetDatum(tmp));
-       /* XXX make me a function */
-       num = IDLIST_NUM(tmp);
-       aidp = IDLIST_DAT(tmp);
-       for (i = 0; i < num; ++i)
-           if (aidp[i] == uid)
+       att = SysCacheGetAttr(GROSYSID,
+                             tuple,
+                             Anum_pg_group_grolist,
+                             &isNull);
+       if (!isNull)
+       {
+           /* be sure the IdList is not toasted */
+           tmp = DatumGetIdListP(att);
+           /* scan it */
+           num = IDLIST_NUM(tmp);
+           aidp = IDLIST_DAT(tmp);
+           for (i = 0; i < num; ++i)
            {
-               found = true;
-               break;
+               if (aidp[i] == uid)
+                   return true;
            }
+       }
    }
    else
-       elog(NOTICE, "in_group: group %d not found", gid);
-   heap_close(relation, RowExclusiveLock);
-   return found;
+       elog(NOTICE, "in_group: group %u not found", gid);
+   return false;
 }
 
 /*
@@ -230,11 +229,10 @@ in_group(AclId uid, AclId gid)
 static int32
 aclcheck(char *relname, Acl *acl, AclId id, AclIdType idtype, AclMode mode)
 {
-   unsigned    i;
    AclItem    *aip,
               *aidat;
-   unsigned    num,
-               found_group;
+   int         i,
+               num;
 
    /*
     * If ACL is null, default to "OK" --- this should not happen,
@@ -252,17 +250,20 @@ aclcheck(char *relname, Acl *acl, AclId id, AclIdType idtype, AclMode mode)
    /*
     * We'll treat the empty ACL like that, too, although this is more
     * like an error (i.e., you manually blew away your ACL array) -- the
-    * system never creates an empty ACL.
+    * system never creates an empty ACL, since there must always be
+    * a "world" entry in the first slot.
     */
    if (num < 1)
    {
        elog(DEBUG, "aclcheck: zero-length ACL, returning 1");
        return ACLCHECK_OK;
    }
+   Assert(aidat->ai_idtype == ACL_IDTYPE_WORLD);
 
    switch (idtype)
    {
        case ACL_IDTYPE_UID:
+           /* Look for exact match to user */
            for (i = 1, aip = aidat + 1;        /* skip world entry */
                 i < num && aip->ai_idtype == ACL_IDTYPE_UID;
                 ++i, ++aip)
@@ -270,34 +271,33 @@ aclcheck(char *relname, Acl *acl, AclId id, AclIdType idtype, AclMode mode)
                if (aip->ai_id == id)
                {
 #ifdef ACLDEBUG_TRACE
-                   elog(DEBUG, "aclcheck: found %d/%d",
+                   elog(DEBUG, "aclcheck: found user %u/%d",
                         aip->ai_id, aip->ai_mode);
 #endif
                    return (aip->ai_mode & mode) ? ACLCHECK_OK : ACLCHECK_NO_PRIV;
                }
            }
-           for (found_group = 0;
+           /* See if he has the permission via any group */
+           for (;
                 i < num && aip->ai_idtype == ACL_IDTYPE_GID;
                 ++i, ++aip)
            {
-               if (in_group(id, aip->ai_id))
+               if (aip->ai_mode & mode)
                {
-                   if (aip->ai_mode & mode)
+                   if (in_group(id, aip->ai_id))
                    {
-                       found_group = 1;
-                       break;
-                   }
-               }
-           }
-           if (found_group)
-           {
 #ifdef ACLDEBUG_TRACE
-               elog(DEBUG, "aclcheck: all groups ok");
+                       elog(DEBUG, "aclcheck: found group %u/%d",
+                            aip->ai_id, aip->ai_mode);
 #endif
-               return ACLCHECK_OK;
+                       return ACLCHECK_OK;
+                   }
+               }
            }
+           /* Else, look to the world entry */
            break;
        case ACL_IDTYPE_GID:
+           /* Look for this group ID */
            for (i = 1, aip = aidat + 1;        /* skip world entry and
                                                 * UIDs */
                 i < num && aip->ai_idtype == ACL_IDTYPE_UID;
@@ -310,14 +310,16 @@ aclcheck(char *relname, Acl *acl, AclId id, AclIdType idtype, AclMode mode)
                if (aip->ai_id == id)
                {
 #ifdef ACLDEBUG_TRACE
-                   elog(DEBUG, "aclcheck: found %d/%d",
+                   elog(DEBUG, "aclcheck: found group %u/%d",
                         aip->ai_id, aip->ai_mode);
 #endif
                    return (aip->ai_mode & mode) ? ACLCHECK_OK : ACLCHECK_NO_PRIV;
                }
            }
+           /* Else, look to the world entry */
            break;
        case ACL_IDTYPE_WORLD:
+           /* Only check the world entry */
            break;
        default:
            elog(ERROR, "aclcheck: bogus ACL id type: %d", idtype);