From 4fd2c69b0799dc581d270262880444584ae17599 Mon Sep 17 00:00:00 2001

From: Noriko Hosoi <nhosoi@redhat.com>

Date: Fri, 9 May 2014 10:10:49 -0700

Subject: [PATCH 210/225] Ticket #47764 - Problem with deletion while

 replicated

Bug description: When checking a child entry on a node, it only

checked the first position, which was normally "deleted" if there

were no more children. But in some cases, a tombstoned child was

placed there.  If it occurred, even though there were no live child

any more, _entryrdn_delete_key returned "has children" and the delete

operation failed.

Fix description: This patch checks all the children of the to-be-

deleted node and if there is no child or all of them are tombstones,

it goes to the next process.  Also, the fixed a typo reported by

chatfield (Thank you!!)

https://fedorahosted.org/389/ticket/47764

Reviewed by chatfield and mreynolds@redhat.com (Thank you both!!)

(cherry picked from commit 832253ea96b83e7ebc16fe507d77090e87aed1c2)

(cherry picked from commit 86b34ca0a002715a263a56b1e8c870dd3035bce4)

(cherry picked from commit efa23ced2a6e3de3389d9b801329066f511bc38c)

(cherry picked from commit ca407f8a684e58067440f57049794c47255cf716)

---

 ldap/servers/slapd/back-ldbm/ldbm_entryrdn.c | 92 +++++++++++++++++++---------

 1 file changed, 64 insertions(+), 28 deletions(-)

diff --git a/ldap/servers/slapd/back-ldbm/ldbm_entryrdn.c b/ldap/servers/slapd/back-ldbm/ldbm_entryrdn.c

index 6426fb7..38b407d 100644

--- a/ldap/servers/slapd/back-ldbm/ldbm_entryrdn.c

+++ b/ldap/servers/slapd/back-ldbm/ldbm_entryrdn.c

@@ -2795,6 +2795,8 @@ _entryrdn_delete_key(backend *be,

     int issuffix = 0;

     Slapi_RDN *tmpsrdn = NULL;

     int db_retry = 0;

+    int done = 0;

+    char buffer[RDN_BULK_FETCH_BUFFER_SIZE]; 

     slapi_log_error(SLAPI_LOG_TRACE, ENTRYRDN_TAG,

                                      "--> _entryrdn_delete_key\n");

@@ -2828,45 +2830,79 @@ _entryrdn_delete_key(backend *be,

     /* check if the target element has a child or not */

     keybuf = slapi_ch_smprintf("%c%u", RDN_INDEX_CHILD, id);

     key.data = (void *)keybuf;

-    key.size = key.ulen = strlen(nrdn) + 1;

+    key.size = key.ulen = strlen(keybuf) + 1;

     key.flags = DB_DBT_USERMEM;    

+    /* Setting the bulk fetch buffer */

     memset(&data, 0, sizeof(data));

-    data.flags = DB_DBT_MALLOC;

+    data.ulen = sizeof(buffer);

+    data.size = sizeof(buffer);

+    data.data = buffer;

+    data.flags = DB_DBT_USERMEM;

-    for (db_retry = 0; db_retry < RETRY_TIMES; db_retry++) {

-        rc = cursor->c_get(cursor, &key, &data, DB_SET);

-        if (rc) {

+    done = 0;

+    while (!done) {

+        rc = cursor->c_get(cursor, &key, &data, DB_SET|DB_MULTIPLE);

+        if (DB_LOCK_DEADLOCK == rc) {

+            slapi_log_error(ENTRYRDN_LOGLEVEL(rc), ENTRYRDN_TAG,

+                            "_entryrdn_delete_key: cursor get deadlock\n");

+#ifdef FIX_TXN_DEADLOCKS

+#error if txn != NULL, have to retry the entire transaction

+#endif

+            /* try again */

+            continue;

+        } else if (DB_NOTFOUND == rc) {

+            /* no children; ok */

+            done = 1;

+            continue;

+        } else if (rc) {

+            _entryrdn_cursor_print_error("_entryrdn_delete_key",

+                                         key.data, data.size, data.ulen, rc);

+            goto bail;

+        }

+        

+        do {

+            rdn_elem *childelem = NULL;

+            DBT dataret;

+            void *ptr;

+            DB_MULTIPLE_INIT(ptr, &data);

+            do {

+                memset(&dataret, 0, sizeof(dataret));

+                DB_MULTIPLE_NEXT(ptr, &data, dataret.data, dataret.size);

+                if (NULL == dataret.data || NULL == ptr) {

+                    break;

+                }

+                childelem = (rdn_elem *)dataret.data;

+                if (!slapi_is_special_rdn(childelem->rdn_elem_nrdn_rdn, RDN_IS_TOMBSTONE)) {

+                    /* there's at least one live child */

+                    slapi_log_error(SLAPI_LOG_FATAL, ENTRYRDN_TAG,

+                                    "_entryrdn_delete_key: Failed to remove %s; "

+                                    "has a child %s\n", nrdn, 

+                                    (char *)childelem->rdn_elem_nrdn_rdn);

+                    rc = -1;

+                    goto bail;

+                }

+            } while (NULL != dataret.data && NULL != ptr);

+retry_get:

+            rc = cursor->c_get(cursor, &key, &data, DB_NEXT_DUP|DB_MULTIPLE);

             if (DB_LOCK_DEADLOCK == rc) {

                 slapi_log_error(ENTRYRDN_LOGLEVEL(rc), ENTRYRDN_TAG,

-                                "_entryrdn_delete_key: cursor get deadlock\n");

+                                "_entryrdn_delete_key: retry cursor get deadlock\n");

+#ifdef FIX_TXN_DEADLOCKS

+#error if txn != NULL, have to retry the entire transaction

+#endif

                 /* try again */

-                if (db_txn) {

-                    goto bail; /* have to abort/retry the entire transaction */

-                } else {

-                    ENTRYRDN_DELAY; /* sleep for a bit then retry immediately */

-                }

-            } else if (DB_NOTFOUND != rc) {

+                goto retry_get;

+            } else if (DB_NOTFOUND == rc) {

+                rc = 0;

+                done = 1;

+                break;

+            } else if (rc) {

                 _entryrdn_cursor_print_error("_entryrdn_delete_key",

                                              key.data, data.size, data.ulen, rc);

                 goto bail;

-            } else {

-                break; /* DB_NOTFOUND - ok */

             }

-        } else {

-            slapi_ch_free(&data.data);

-            slapi_log_error(SLAPI_LOG_FATAL, ENTRYRDN_TAG,

-                            "_entryrdn_delete_key: Failed to remove %s; "

-                            "has children\n", nrdn);

-            rc = -1;

-            goto bail;

-        }

-    }

-    if (RETRY_TIMES == db_retry) {

-        slapi_log_error(SLAPI_LOG_FATAL, ENTRYRDN_TAG,

-                        "_entryrdn_delete_key: failed after [%d] iterations\n", db_retry);

-        rc = DB_LOCK_DEADLOCK;

-        goto bail;

+        } while (0 == rc);

     }

     workid = id;

-- 

1.8.1.4