Bug 741744 - part3 - MOD operations with chained delete/add get back error 53

https://bugzilla.redhat.com/show_bug.cgi?id=741744
Resolves: bug 741744
Bug Description: part3 - MOD operations with chained delete/add get back err
Reviewed by: nhosoi (Thanks!)
Branch: master
Fix Description: Remove the mods from the mods list that we don't want the
dse code to handle.  Add back the original values of the mods that we do
want the dse code to handle.  Tell the dse code to reapply the mods.
Platforms tested: RHEL6 x86_64
Flag Day: no
Doc impact: no

ldap/servers/slapd/back-ldbm/ldbm_config.c

@@ -1861,6 +1861,15 @@ static int parse_ldbm_config_entry(struct ldbminfo *li, Slapi_Entry *e, config_i
     return 0;
 }
 
+/* helper for deleting mods (we do not want to be applied) from the mods array */
+static void
+mod_free(LDAPMod *mod)
+{
+	ber_bvecfree(mod->mod_bvalues);
+	slapi_ch_free((void**)&(mod->mod_type));
+	slapi_ch_free((void**)&mod);
+}
+
 /*
  * Returns:
  *   SLAPI_DSE_CALLBACK_ERROR on failure
@@ -1874,7 +1883,9 @@ int ldbm_config_modify_entry_callback(Slapi_PBlock *pb, Slapi_Entry* entryBefore
     int rc = LDAP_SUCCESS; 
     int apply_mod = 0; 
     struct ldbminfo *li= (struct ldbminfo *) arg;
-    
+    int reapply_mods = 0;
+    int idx = 0;
+
     /* This lock is probably way too conservative, but we don't expect much
      * contention for it. */
     PR_Lock(li->li_config_mutex);
@@ -1890,12 +1901,29 @@ int ldbm_config_modify_entry_callback(Slapi_PBlock *pb, Slapi_Entry* entryBefore
     for ( apply_mod = 0; apply_mod <= 1 && LDAP_SUCCESS == rc; apply_mod++ ) {
         for (i = 0; mods[i] && LDAP_SUCCESS == rc; i++) {
             attr_name = mods[i]->mod_type;
-            
+
             /* There are some attributes that we don't care about, like modifiersname. */
             if (ldbm_config_ignored_attr(attr_name)) {
+                if (apply_mod) {
+                    Slapi_Attr *origattr = NULL;
+                    Slapi_ValueSet *origvalues = NULL;
+                    mods[idx++] = mods[i];
+                    /* we also need to restore the entryAfter e to its original
+                       state, because the dse code will attempt to reapply
+                       the mods again */
+                    slapi_entry_attr_find(entryBefore, attr_name, &origattr);
+                    if (NULL != origattr) {
+                        slapi_attr_get_valueset(origattr, &origvalues);
+                        if (NULL != origvalues) {
+                            slapi_entry_add_valueset(e, attr_name, origvalues);
+                            slapi_valueset_free(origvalues);
+                        }
+                    }
+                }
                 continue;
             }
 
+            reapply_mods = 1; /* there is at least one mod we removed */
             /* when deleting a value, and this is the last or only value, set
                the config param to its default value
                when adding a value, if the value is set to its default value, replace
@@ -1908,10 +1936,19 @@ int ldbm_config_modify_entry_callback(Slapi_PBlock *pb, Slapi_Entry* entryBefore
                                  ((li->li_flags&LI_FORCE_MOD_CONFIG)?
                                   CONFIG_PHASE_INTERNAL:CONFIG_PHASE_RUNNING),
                                  apply_mod, mods[i]->mod_op); 
+            if (apply_mod) {
+                mod_free(mods[i]);
+                mods[i] = NULL;
+            }
         } 
     } 
     
     PR_Unlock(li->li_config_mutex);
+
+    if (reapply_mods) {
+        mods[idx] = NULL;
+        slapi_pblock_set(pb, SLAPI_DSE_REAPPLY_MODS, &reapply_mods);
+    }
     
     *returncode= rc; 
     if(LDAP_SUCCESS == rc) {