bug#18594 ndb_restore log boken in 5.1

- corrected previous patch
- read log entry variables out into explicit variables for siimpler code (and backwards compatability code)

storage/ndb/tools/restore/Restore.cpp

@@ -961,15 +961,15 @@ RestoreLogIterator::RestoreLogIterator(const RestoreMetaData & md)
 const LogEntry *
 RestoreLogIterator::getNextLogEntry(int & res) {
   // Read record length
-  typedef BackupFormat::LogFile::LogEntry LogE;
-  typedef BackupFormat::LogFile::LogEntry_no_fragid LogE_no_fragid;
-  const Uint32 offset= 3;
-  assert(offset == (offsetof(LogE, Data) >> 2) - 1);
-  LogE * logE= 0;
-  Uint32 len= ~0;
   const Uint32 stopGCP = m_metaData.getStopGCP();
-  NdbAutoPtr<char> ap1;
+  Uint32 tableId;
+  Uint32 triggerEvent;
+  Uint32 frag_id;
+  Uint32 *attr_data;
+  Uint32 attr_data_len;
   do {
+    Uint32 len;
+    Uint32 *logEntryPtr;
     if (buffer_read_ahead(&len, sizeof(Uint32), 1) != 1){
       res= -1;
       return 0;
@@ -977,7 +977,7 @@ RestoreLogIterator::getNextLogEntry(int & res) {
     len= ntohl(len);
 
     Uint32 data_len = sizeof(Uint32) + len*4;
-    if (buffer_get_ptr((void **)(&logE), 1, data_len) != data_len) {
+    if (buffer_get_ptr((void **)(&logEntryPtr), 1, data_len) != data_len) {
       res= -2;
       return 0;
     }
@@ -986,7 +986,8 @@ RestoreLogIterator::getNextLogEntry(int & res) {
       res= 0;
       return 0;
     }
-    if (m_metaData.getFileHeader().NdbVersion < NDBD_FRAGID_VERSION)
+
+    if (unlikely(m_metaData.getFileHeader().NdbVersion < NDBD_FRAGID_VERSION))
     {
       /*
         FragId was introduced in LogEntry in version
@@ -994,48 +995,39 @@ RestoreLogIterator::getNextLogEntry(int & res) {
         We set FragId to 0 in older versions (these versions
         do not support restore of user defined partitioned
         tables.
-
-        These log entries miss one Uint32 FragId, hence missing_len=1
-
-        Reconstruct a new log entry with old.
       */
-      const Uint32 missing_len= 1;
-      assert((offsetof(LogE, Data) - offsetof(LogE_no_fragid, Data)) >> 2 ==
-             missing_len);
-      LogE_no_fragid * logE_no_fragid= (LogE_no_fragid *)logE;
-      
-      int i;
-      LogE *tmpLogE= (LogE*)NdbMem_Allocate(data_len + missing_len*4);
-      if (!tmpLogE)
-      {
-        res = -2;
-        return 0;
-      }
-      ap1.reset((char*)tmpLogE);
-      bzero(tmpLogE, data_len + missing_len*4);
-      /* correct len to reflect new logEntry version length */
-      len+= missing_len;
-      tmpLogE->Length = logE_no_fragid->Length;
-      tmpLogE->TableId = logE_no_fragid->TableId;
-      tmpLogE->TriggerEvent = logE_no_fragid->TriggerEvent;
-      for (i = 0; i < len - offset; i++)
-        tmpLogE->Data[i] = logE_no_fragid->Data[i];
-      logE= tmpLogE;
+      typedef BackupFormat::LogFile::LogEntry_no_fragid LogE_no_fragid;
+      LogE_no_fragid * logE_no_fragid= (LogE_no_fragid *)logEntryPtr;
+      tableId= ntohl(logE_no_fragid->TableId);
+      triggerEvent= ntohl(logE_no_fragid->TriggerEvent);
+      frag_id= 0;
+      attr_data= &logE_no_fragid->Data[0];
+      attr_data_len= len - ((offsetof(LogE_no_fragid, Data) >> 2) - 1);
+    }
+    else /* normal case */
+    {
+      typedef BackupFormat::LogFile::LogEntry LogE;
+      LogE * logE= (LogE *)logEntryPtr;
+      tableId= ntohl(logE->TableId);
+      triggerEvent= ntohl(logE->TriggerEvent);
+      frag_id= ntohl(logE->FragId);
+      attr_data= &logE->Data[0];
+      attr_data_len= len - ((offsetof(LogE, Data) >> 2) - 1);
     }
-    logE->TableId= ntohl(logE->TableId);
-    logE->TriggerEvent= ntohl(logE->TriggerEvent);
-    
-    const bool hasGcp= (logE->TriggerEvent & 0x10000) != 0;
-    logE->TriggerEvent &= 0xFFFF;
     
+    const bool hasGcp= (triggerEvent & 0x10000) != 0;
+    triggerEvent &= 0xFFFF;
+
     if(hasGcp){
+      // last attr_data is gci info
+      attr_data_len--;
       len--;
-      m_last_gci = ntohl(logE->Data[len-offset]);
+      m_last_gci = ntohl(*(attr_data + attr_data_len));
     }
   } while(m_last_gci > stopGCP + 1);
-  
-  m_logEntry.m_table = m_metaData.getTable(logE->TableId);
-  switch(logE->TriggerEvent){
+
+  m_logEntry.m_table = m_metaData.getTable(tableId);
+  switch(triggerEvent){
   case TriggerEvent::TE_INSERT:
     m_logEntry.m_type = LogEntry::LE_INSERT;
     break;
@@ -1053,10 +1045,10 @@ RestoreLogIterator::getNextLogEntry(int & res) {
   const TableS * tab = m_logEntry.m_table;
   m_logEntry.clear();
 
-  AttributeHeader * ah = (AttributeHeader *)&logE->Data[0];
-  AttributeHeader *end = (AttributeHeader *)&logE->Data[len - offset];
+  AttributeHeader * ah = (AttributeHeader *)attr_data;
+  AttributeHeader *end = (AttributeHeader *)(attr_data + attr_data_len);
   AttributeS *  attr;
-  m_logEntry.m_frag_id = ntohl(logE->FragId);
+  m_logEntry.m_frag_id = frag_id;
   while(ah < end){
     attr= m_logEntry.add_attr();
     if(attr == NULL) {