Moved all code related to engine_condition_pushdown to a new class,

ha_ndbcluster_cond.
Added new files:
sql/ha_ndbcluster_cond.h
sql/ha_ndbcluster_cond.cc


sql/ha_ndbcluster_cond.cc:
  BitKeeper file /windows/Linux_space/MySQL/mysql-5.0-ndb/sql/ha_ndbcluster_cond.cc
sql/ha_ndbcluster_cond.h:
  BitKeeper file /windows/Linux_space/MySQL/mysql-5.0-ndb/sql/ha_ndbcluster_cond.h
sql/Makefile.am:
  Added compilation of new separate files for engine_condition_pushdown
sql/ha_ndbcluster.cc:
  Moved all code related to engine_condition_pushdown to ha_ndbcluster_cond
sql/ha_ndbcluster.h:
  Moved all code related to engine_condition_pushdown to ha_ndbcluster_cond

1 files changed, 469 insertions, 0 deletions

diff --git a/sql/ha_ndbcluster_cond.h b/sql/ha_ndbcluster_cond.h
new file mode 100644
index 00000000000..5afa817fade
--- /dev/null
+++ b/sql/ha_ndbcluster_cond.h
@@ -0,0 +1,469 @@
+/* Copyright (C) 2000-2007 MySQL AB
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; version 2 of the License.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
+
+/*
+  This file defines the data structures used by engine condition pushdown in
+  the NDB Cluster handler
+*/
+
+#ifdef USE_PRAGMA_INTERFACE
+#pragma interface                       /* gcc class implementation */
+#endif
+
+typedef enum ndb_item_type {
+  NDB_VALUE = 0,   // Qualified more with Item::Type
+  NDB_FIELD = 1,   // Qualified from table definition
+  NDB_FUNCTION = 2,// Qualified from Item_func::Functype
+  NDB_END_COND = 3 // End marker for condition group
+} NDB_ITEM_TYPE;
+
+typedef enum ndb_func_type {
+  NDB_EQ_FUNC = 0,
+  NDB_NE_FUNC = 1,
+  NDB_LT_FUNC = 2,
+  NDB_LE_FUNC = 3,
+  NDB_GT_FUNC = 4,
+  NDB_GE_FUNC = 5,
+  NDB_ISNULL_FUNC = 6,
+  NDB_ISNOTNULL_FUNC = 7,
+  NDB_LIKE_FUNC = 8,
+  NDB_NOTLIKE_FUNC = 9,
+  NDB_NOT_FUNC = 10,
+  NDB_UNKNOWN_FUNC = 11,
+  NDB_COND_AND_FUNC = 12,
+  NDB_COND_OR_FUNC = 13,
+  NDB_UNSUPPORTED_FUNC = 14
+} NDB_FUNC_TYPE;
+
+typedef union ndb_item_qualification {
+  Item::Type value_type; 
+  enum_field_types field_type; // Instead of Item::FIELD_ITEM
+  NDB_FUNC_TYPE function_type; // Instead of Item::FUNC_ITEM
+} NDB_ITEM_QUALIFICATION;
+
+typedef struct ndb_item_field_value {
+  Field* field;
+  int column_no;
+} NDB_ITEM_FIELD_VALUE;
+
+typedef union ndb_item_value {
+  const Item *item;
+  NDB_ITEM_FIELD_VALUE *field_value;
+  uint arg_count;
+} NDB_ITEM_VALUE;
+
+struct negated_function_mapping
+{
+  NDB_FUNC_TYPE pos_fun;
+  NDB_FUNC_TYPE neg_fun;
+};
+
+/*
+  Define what functions can be negated in condition pushdown.
+  Note, these HAVE to be in the same order as in definition enum
+*/
+static const negated_function_mapping neg_map[]= 
+{
+  {NDB_EQ_FUNC, NDB_NE_FUNC},
+  {NDB_NE_FUNC, NDB_EQ_FUNC},
+  {NDB_LT_FUNC, NDB_GE_FUNC},
+  {NDB_LE_FUNC, NDB_GT_FUNC},
+  {NDB_GT_FUNC, NDB_LE_FUNC},
+  {NDB_GE_FUNC, NDB_LT_FUNC},
+  {NDB_ISNULL_FUNC, NDB_ISNOTNULL_FUNC},
+  {NDB_ISNOTNULL_FUNC, NDB_ISNULL_FUNC},
+  {NDB_LIKE_FUNC, NDB_NOTLIKE_FUNC},
+  {NDB_NOTLIKE_FUNC, NDB_LIKE_FUNC},
+  {NDB_NOT_FUNC, NDB_UNSUPPORTED_FUNC},
+  {NDB_UNKNOWN_FUNC, NDB_UNSUPPORTED_FUNC},
+  {NDB_COND_AND_FUNC, NDB_UNSUPPORTED_FUNC},
+  {NDB_COND_OR_FUNC, NDB_UNSUPPORTED_FUNC},
+  {NDB_UNSUPPORTED_FUNC, NDB_UNSUPPORTED_FUNC}
+};
+  
+/*
+  This class is the construction element for serialization of Item tree 
+  in condition pushdown.
+  An instance of Ndb_Item represents a constant, table field reference,
+  unary or binary comparison predicate, and start/end of AND/OR.
+  Instances of Ndb_Item are stored in a linked list implemented by Ndb_cond
+  class.
+  The order of elements produced by Ndb_cond::next corresponds to
+  breadth-first traversal of the Item (i.e. expression) tree in prefix order.
+  AND and OR have arbitrary arity, so the end of AND/OR group is marked with  
+  Ndb_item with type == NDB_END_COND.
+  NOT items represent negated conditions and generate NAND/NOR groups.
+*/
+class Ndb_item : public Sql_alloc
+{
+public:
+  Ndb_item(NDB_ITEM_TYPE item_type) : type(item_type) {};
+  Ndb_item(NDB_ITEM_TYPE item_type, 
+           NDB_ITEM_QUALIFICATION item_qualification,
+           const Item *item_value)
+    : type(item_type), qualification(item_qualification)
+  { 
+    switch(item_type) {
+    case(NDB_VALUE):
+      value.item= item_value;
+      break;
+    case(NDB_FIELD): {
+      NDB_ITEM_FIELD_VALUE *field_value= new NDB_ITEM_FIELD_VALUE();
+      Item_field *field_item= (Item_field *) item_value;
+      field_value->field= field_item->field;
+      field_value->column_no= -1; // Will be fetched at scan filter generation
+      value.field_value= field_value;
+      break;
+    }
+    case(NDB_FUNCTION):
+      value.item= item_value;
+      value.arg_count= ((Item_func *) item_value)->argument_count();
+      break;
+    case(NDB_END_COND):
+      break;
+    }
+  };
+  Ndb_item(Field *field, int column_no) : type(NDB_FIELD)
+  {
+    NDB_ITEM_FIELD_VALUE *field_value= new NDB_ITEM_FIELD_VALUE();
+    qualification.field_type= field->type();
+    field_value->field= field;
+    field_value->column_no= column_no;
+    value.field_value= field_value;
+  };
+  Ndb_item(Item_func::Functype func_type, const Item *item_value) 
+    : type(NDB_FUNCTION)
+  {
+    qualification.function_type= item_func_to_ndb_func(func_type);
+    value.item= item_value;
+    value.arg_count= ((Item_func *) item_value)->argument_count();
+  };
+  Ndb_item(Item_func::Functype func_type, uint no_args) 
+    : type(NDB_FUNCTION)
+  {
+    qualification.function_type= item_func_to_ndb_func(func_type);
+    value.arg_count= no_args;
+  };
+  ~Ndb_item()
+  { 
+    if (type == NDB_FIELD)
+      {
+        delete value.field_value;
+        value.field_value= NULL;
+      }
+  };
+
+  uint32 pack_length() 
+  { 
+    switch(type) {
+    case(NDB_VALUE):
+      if(qualification.value_type == Item::STRING_ITEM)
+        return value.item->str_value.length();
+      break;
+    case(NDB_FIELD):
+      return value.field_value->field->pack_length(); 
+    default:
+      break;
+    }
+    
+    return 0;
+  };
+
+  Field * get_field() { return value.field_value->field; };
+
+  int get_field_no() { return value.field_value->column_no; };
+
+  int argument_count() 
+  { 
+    return value.arg_count;
+  };
+
+  const char* get_val() 
+  {  
+    switch(type) {
+    case(NDB_VALUE):
+      if(qualification.value_type == Item::STRING_ITEM)
+        return value.item->str_value.ptr();
+      break;
+    case(NDB_FIELD):
+      return value.field_value->field->ptr; 
+    default:
+      break;
+    }
+    
+    return NULL;
+  };
+
+  void save_in_field(Ndb_item *field_item)
+  {
+    Field *field = field_item->value.field_value->field;
+    const Item *item= value.item;
+
+    if (item && field)
+      ((Item *)item)->save_in_field(field, false);
+  };
+
+  static NDB_FUNC_TYPE item_func_to_ndb_func(Item_func::Functype fun)
+  {
+    switch (fun) {
+    case (Item_func::EQ_FUNC): { return NDB_EQ_FUNC; }
+    case (Item_func::NE_FUNC): { return NDB_NE_FUNC; }
+    case (Item_func::LT_FUNC): { return NDB_LT_FUNC; }
+    case (Item_func::LE_FUNC): { return NDB_LE_FUNC; }
+    case (Item_func::GT_FUNC): { return NDB_GT_FUNC; }
+    case (Item_func::GE_FUNC): { return NDB_GE_FUNC; }
+    case (Item_func::ISNULL_FUNC): { return NDB_ISNULL_FUNC; }
+    case (Item_func::ISNOTNULL_FUNC): { return NDB_ISNOTNULL_FUNC; }
+    case (Item_func::LIKE_FUNC): { return NDB_LIKE_FUNC; }
+    case (Item_func::NOT_FUNC): { return NDB_NOT_FUNC; }
+    case (Item_func::UNKNOWN_FUNC): { return NDB_UNKNOWN_FUNC; }
+    case (Item_func::COND_AND_FUNC): { return NDB_COND_AND_FUNC; }
+    case (Item_func::COND_OR_FUNC): { return NDB_COND_OR_FUNC; }
+    default: { return NDB_UNSUPPORTED_FUNC; }
+    }
+  };
+
+  static NDB_FUNC_TYPE negate(NDB_FUNC_TYPE fun)
+  {
+    uint i= (uint) fun;
+    DBUG_ASSERT(fun == neg_map[i].pos_fun);
+    return  neg_map[i].neg_fun;
+  };
+
+  NDB_ITEM_TYPE type;
+  NDB_ITEM_QUALIFICATION qualification;
+ private:
+  NDB_ITEM_VALUE value;
+};
+
+/*
+  This class implements a linked list used for storing a
+  serialization of the Item tree for condition pushdown.
+ */
+class Ndb_cond : public Sql_alloc
+{
+ public:
+  Ndb_cond() : ndb_item(NULL), next(NULL), prev(NULL) {};
+  ~Ndb_cond() 
+  { 
+    if (ndb_item) delete ndb_item; 
+    ndb_item= NULL; 
+    if (next) delete next;
+    next= prev= NULL; 
+  };
+  Ndb_item *ndb_item;
+  Ndb_cond *next;
+  Ndb_cond *prev;
+};
+
+/*
+  This class implements a stack for storing several conditions
+  for pushdown (represented as serialized Item trees using Ndb_cond).
+  The current implementation only pushes one condition, but is
+  prepared for handling several (C1 AND C2 ...) if the logic for 
+  pushing conditions is extended in sql_select.
+*/
+class Ndb_cond_stack : public Sql_alloc
+{
+ public:
+  Ndb_cond_stack() : ndb_cond(NULL), next(NULL) {};
+  ~Ndb_cond_stack() 
+  { 
+    if (ndb_cond) delete ndb_cond; 
+    ndb_cond= NULL; 
+    if (next) delete next;
+    next= NULL; 
+  };
+  Ndb_cond *ndb_cond;
+  Ndb_cond_stack *next;
+};
+
+class Ndb_rewrite_context : public Sql_alloc
+{
+public:
+  Ndb_rewrite_context(Item_func *func) 
+    : func_item(func), left_hand_item(NULL), count(0) {};
+  ~Ndb_rewrite_context()
+  {
+    if (next) delete next;
+  }
+  const Item_func *func_item;
+  const Item *left_hand_item;
+  uint count;
+  Ndb_rewrite_context *next;
+};
+
+/*
+  This class is used for storing the context when traversing
+  the Item tree. It stores a reference to the table the condition
+  is defined on, the serialized representation being generated, 
+  if the condition found is supported, and information what is
+  expected next in the tree inorder for the condition to be supported.
+*/
+class Ndb_cond_traverse_context : public Sql_alloc
+{
+ public:
+  Ndb_cond_traverse_context(TABLE *tab, void* ndb_tab, Ndb_cond_stack* stack)
+    : table(tab), ndb_table(ndb_tab), 
+    supported(TRUE), stack_ptr(stack), cond_ptr(NULL),
+    skip(0), collation(NULL), rewrite_stack(NULL)
+  {
+    // Allocate type checking bitmaps   
+    bitmap_init(&expect_mask, 0, 512, FALSE);
+    bitmap_init(&expect_field_type_mask, 0, 512, FALSE);
+    bitmap_init(&expect_field_result_mask, 0, 512, FALSE);
+
+    if (stack)
+      cond_ptr= stack->ndb_cond;
+  };
+  ~Ndb_cond_traverse_context()
+  {
+    bitmap_free(&expect_mask);
+    bitmap_free(&expect_field_type_mask);
+    bitmap_free(&expect_field_result_mask);
+    if (rewrite_stack) delete rewrite_stack;
+  }
+  void expect(Item::Type type)
+  {
+    bitmap_set_bit(&expect_mask, (uint) type);
+    if (type == Item::FIELD_ITEM) expect_all_field_types();
+  };
+  void dont_expect(Item::Type type)
+  {
+    bitmap_clear_bit(&expect_mask, (uint) type);
+  };
+  bool expecting(Item::Type type)
+  {
+    return bitmap_is_set(&expect_mask, (uint) type);
+  };
+  void expect_nothing()
+  {
+    bitmap_clear_all(&expect_mask);
+  };
+  bool expecting_nothing()
+  {
+    return bitmap_is_clear_all(&expect_mask);
+  }
+  void expect_only(Item::Type type)
+  {
+    expect_nothing();
+    expect(type);
+  };
+
+  void expect_field_type(enum_field_types type)
+  {
+    bitmap_set_bit(&expect_field_type_mask, (uint) type);
+  };
+  void expect_all_field_types()
+  {
+    bitmap_set_all(&expect_field_type_mask);
+  };
+  bool expecting_field_type(enum_field_types type)
+  {
+    return bitmap_is_set(&expect_field_type_mask, (uint) type);
+  };
+  void expect_no_field_type()
+  {
+    bitmap_clear_all(&expect_field_type_mask);
+  };
+  bool expecting_no_field_type()
+  {
+    return bitmap_is_clear_all(&expect_field_type_mask);
+  }
+  void expect_only_field_type(enum_field_types result)
+  {
+    expect_no_field_type();
+    expect_field_type(result);
+  };
+
+  void expect_field_result(Item_result result)
+  {
+    bitmap_set_bit(&expect_field_result_mask, (uint) result);
+  };
+  bool expecting_field_result(Item_result result)
+  {
+    return bitmap_is_set(&expect_field_result_mask, (uint) result);
+  };
+  void expect_no_field_result()
+  {
+    bitmap_clear_all(&expect_field_result_mask);
+  };
+  bool expecting_no_field_result()
+  {
+    return bitmap_is_clear_all(&expect_field_result_mask);
+  }
+  void expect_only_field_result(Item_result result)
+  {
+    expect_no_field_result();
+    expect_field_result(result);
+  };
+  void expect_collation(CHARSET_INFO* col)
+  {
+    collation= col;
+  };
+  bool expecting_collation(CHARSET_INFO* col)
+  {
+    bool matching= (!collation) ? true : (collation == col);
+    collation= NULL;
+
+    return matching;
+  };
+
+  TABLE* table;
+  void* ndb_table;
+  bool supported;
+  Ndb_cond_stack* stack_ptr;
+  Ndb_cond* cond_ptr;
+  MY_BITMAP expect_mask;
+  MY_BITMAP expect_field_type_mask;
+  MY_BITMAP expect_field_result_mask;
+  uint skip;
+  CHARSET_INFO* collation;
+  Ndb_rewrite_context *rewrite_stack;
+};
+
+class ha_ndbcluster;
+
+class ha_ndbcluster_cond
+{
+public:
+  ha_ndbcluster_cond() 
+  : m_cond_stack(NULL)
+  {}
+  ~ha_ndbcluster_cond() 
+  { if (m_cond_stack) delete m_cond_stack; }
+  const COND *cond_push(const COND *cond, 
+                        TABLE *table, NdbDictionary::Table *ndb_table);
+  void cond_pop();
+  void cond_clear();
+  int generate_scan_filter(NdbScanOperation* op);
+  int generate_scan_filter_from_cond(NdbScanFilter& filter);
+  int generate_scan_filter_from_key(NdbScanOperation* op,
+                                    const KEY* key_info, 
+                                    const byte *key, 
+                                    uint key_len,
+                                    byte *buf);
+private:
+  bool serialize_cond(const COND *cond, Ndb_cond_stack *ndb_cond,
+		      TABLE *table, NdbDictionary::Table *ndb_table);
+  int build_scan_filter_predicate(Ndb_cond* &cond, 
+                                  NdbScanFilter* filter,
+                                  bool negated= false);
+  int build_scan_filter_group(Ndb_cond* &cond, 
+                              NdbScanFilter* filter);
+  int build_scan_filter(Ndb_cond* &cond, NdbScanFilter* filter);
+
+  Ndb_cond_stack *m_cond_stack;
+};