Patch for WL#2894: Make stored routine variables work

according to the standard.

The idea is to use Field-classes to implement stored routines
variables. Also, we should provide facade to Item-hierarchy
by Item_field class (it is necessary, since SRVs take part
in expressions).

The patch fixes the following bugs:
  - BUG#8702: Stored Procedures: No Error/Warning shown for inappropriate data 
    type matching; 
 
  - BUG#8768: Functions: For any unsigned data type, -ve values can be passed 
    and returned; 
 
  - BUG#8769: Functions: For Int datatypes, out of range values can be passed 
    and returned; 
 
  - BUG#9078: STORED PROCDURE: Decimal digits are not displayed when we use 
    DECIMAL datatype; 
 
  - BUG#9572: Stored procedures: variable type declarations ignored; 
 
  - BUG#12903: upper function does not work inside a function; 
 
  - BUG#13705: parameters to stored procedures are not verified; 
 
  - BUG#13808: ENUM type stored procedure parameter accepts non-enumerated
    data; 
 
  - BUG#13909: Varchar Stored Procedure Parameter always BINARY string (ignores 
    CHARACTER SET); 
 
  - BUG#14161: Stored procedure cannot retrieve bigint unsigned;

  - BUG#14188: BINARY variables have no 0x00 padding;

  - BUG#15148: Stored procedure variables accept non-scalar values;


mysql-test/r/ctype_ujis.result:
  Explicitly specify correct charset.
mysql-test/r/schema.result:
  Drop our test database to not affect this test if some test
  left it cause of failure.
mysql-test/r/show_check.result:
  Drop our test database to not affect this test if some test
  left it cause of failure.
mysql-test/r/skip_name_resolve.result:
  Ignore columns with unpredictable values.
mysql-test/r/sp-big.result:
  Add cleanup statement.
mysql-test/r/sp-dynamic.result:
  Add cleanup statements.
mysql-test/r/sp.result:
  Update result file.
mysql-test/r/sum_distinct-big.result:
  Update result file.
mysql-test/r/type_newdecimal-big.result:
  Update result file.
mysql-test/t/ctype_ujis.test:
  Explicitly specify correct charset.
mysql-test/t/schema.test:
  Drop our test database to not affect this test if some test
  left it cause of failure.
mysql-test/t/show_check.test:
  Drop our test database to not affect this test if some test
  left it cause of failure.
mysql-test/t/skip_name_resolve.test:
  Ignore columns with unpredictable values.
mysql-test/t/sp-big.test:
  Add cleanup statement.
mysql-test/t/sp-dynamic.test:
  Add cleanup statements.
mysql-test/t/sp.test:
  Non-scalar values prohibited for assignment to SP-vars;
  polishing.
mysql-test/t/type_newdecimal-big.test:
  Update type specification so that the variables
  can contain the large values used in the test.
sql/field.cc:
  Extract create_field::init() to initialize an existing
  instance of create_field from new_create_field().
sql/field.h:
  Extract create_field::init() to initialize an existing
  instance of create_field from new_create_field().
sql/item.cc:
  - Introduce a new class: Item_sp_variable -- a base class
    of stored-routine-variables classes;
  - Introduce Item_case_expr -- an Item, which is used to access
    to the expression of CASE statement;
sql/item.h:
  - Introduce a new class: Item_sp_variable -- a base class
    of stored-routine-variables classes;
  - Introduce Item_case_expr -- an Item, which is used to access
    to the expression of CASE statement;
sql/item_func.cc:
  Pass the Field (instead of Item) for the return value of
  a function to the function execution routine.
sql/item_func.h:
  Pass the Field (instead of Item) for the return value of
  a function to the function execution routine.
sql/mysql_priv.h:
  Move create_virtual_tmp_table() out of sql_select.h.
sql/sp.cc:
  Use create_result_field() instead of make_field().
sql/sp_head.cc:
  - Add a function to map enum_field_types to Item::Type;
  - Add sp_instr_push_case_expr instruction -- an instruction
    to push CASE expression into the active running context;
  - Add sp_instr_pop_case_expr instruction -- an instruction
    to pop CASE expression from the active running context;
  - Adapt the SP-execution code to using Fields instead of Items
    for SP-vars;
  - Use create_field structure for field description instead of
    a set of members.
sql/sp_head.h:
  - Add a function to map enum_field_types to Item::Type;
  - Add sp_instr_push_case_expr instruction -- an instruction
    to push CASE expression into the active running context;
  - Add sp_instr_pop_case_expr instruction -- an instruction
    to pop CASE expression from the active running context;
  - Adapt the SP-execution code to using Fields instead of Items
    for SP-vars;
  - Use create_field structure for field description instead of
    a set of members.
sql/sp_pcontext.cc:
  - Change rules to assign an index of SP-variable: use
    transparent index;
  - Add an operation to retrieve a list of defined SP-vars
    from the processing context recursively.
sql/sp_pcontext.h:
  - Change rules to assign an index of SP-variable: use
    transparent index;
  - Add an operation to retrieve a list of defined SP-vars
    from the processing context recursively.
sql/sp_rcontext.cc:
  - Change rules to assign an index of SP-variable: use
    transparent index;
  - Use a tmp virtual table to store SP-vars instead of Items;
  - Provide operations to work with CASE expresion.
sql/sp_rcontext.h:
  - Change rules to assign an index of SP-variable: use
    transparent index;
  - Use a tmp virtual table to store SP-vars instead of Items;
  - Provide operations to work with CASE expresion.
sql/sql_class.cc:
  - Reflect Item_splocal ctor changes;
  - Item_splocal::get_offset() has been renamed to get_var_idx().
sql/sql_class.h:
  Polishing.
sql/sql_parse.cc:
  Extract create_field::init() to initialize an existing
  instance of create_field from new_create_field().
sql/sql_select.cc:
  Take care of BLOB columns in create_virtual_tmp_table().
sql/sql_select.h:
  Move create_virtual_tmp_table() out of sql_select.h.
sql/sql_trigger.cc:
  Use boolean constants for boolean type instead of numerical ones.
sql/sql_yacc.yy:
  Provide an instance of create_field for each SP-var.
mysql-test/include/sp-vars.inc:
  The definitions of common-procedures, which are created
  under different circumstances.
mysql-test/r/sp-vars.result:
  Result file for the SP-vars test.
mysql-test/sp-vars.test:
  A new test for checking SP-vars functionality.

1 files changed, 84 insertions, 14 deletions

diff --git a/sql/sp_pcontext.h b/sql/sp_pcontext.h
index 5c5890f82cd..6d803362d86 100644
--- a/sql/sp_pcontext.h
+++ b/sql/sp_pcontext.h
@@ -34,8 +34,16 @@ typedef struct sp_pvar
   LEX_STRING name;
   enum enum_field_types type;
   sp_param_mode_t mode;
-  uint offset;			// Offset in current frame
+  
+  /*
+    offset -- basically, this is an index of variable in the scope of root
+    parsing context. This means, that all variables in a stored routine
+    have distinct indexes/offsets.
+  */
+  uint offset;
+
   Item *dflt;
+  create_field field_def;
 } sp_pvar_t;
 
 
@@ -114,9 +122,9 @@ class sp_pcontext : public Sql_alloc
   //
 
   inline uint
-  max_pvars()
+  total_pvars()
   {
-    return m_psubsize + m_pvar.elements;
+    return m_total_pvars;
   }
 
   inline uint
@@ -155,16 +163,15 @@ class sp_pcontext : public Sql_alloc
       p->dflt= it;
   }
 
-  void
+  sp_pvar_t *
   push_pvar(LEX_STRING *name, enum enum_field_types type, sp_param_mode_t mode);
 
-  // Pop the last 'num' slots of the frame
-  inline void
-  pop_pvar(uint num = 1)
-  {
-    while (num--)
-      pop_dynamic(&m_pvar);
-  }
+  /*
+    Retrieve definitions of fields from the current context and its
+    children.
+  */
+  void
+  retrieve_field_definitions(List<create_field> *field_def_lst);
 
   // Find by name
   sp_pvar_t *
@@ -175,7 +182,7 @@ class sp_pcontext : public Sql_alloc
   find_pvar(uint offset);
 
   /*
-    Set the current scope boundary (for default values)
+    Set the current scope boundary (for default values).
     The argument is the number of variables to skip.   
   */
   inline void
@@ -184,6 +191,45 @@ class sp_pcontext : public Sql_alloc
     m_pboundary= n;
   }
 
+  /*
+    CASE expressions support.
+  */
+
+  inline int
+  register_case_expr()
+  {
+    return m_num_case_exprs++;
+  }
+
+  inline int
+  get_num_case_exprs() const
+  {
+    return m_num_case_exprs;
+  }
+
+  inline bool
+  push_case_expr_id(int case_expr_id)
+  {
+    return insert_dynamic(&m_case_expr_id_lst, (gptr) &case_expr_id);
+  }
+
+  inline void
+  pop_case_expr_id()
+  {
+    pop_dynamic(&m_case_expr_id_lst);
+  }
+
+  inline int
+  get_current_case_expr_id() const
+  {
+    int case_expr_id;
+
+    get_dynamic((DYNAMIC_ARRAY*)&m_case_expr_id_lst, (gptr) &case_expr_id,
+                m_case_expr_id_lst.elements - 1);
+
+    return case_expr_id;
+  }
+
   //
   // Labels
   //
@@ -280,8 +326,18 @@ class sp_pcontext : public Sql_alloc
 
 protected:
 
+  /*
+    m_total_pvars -- number of variables (including all types of arguments)
+    in this context including all children contexts.
+    
+    m_total_pvars >= m_pvar.elements.
+
+    m_total_pvars of the root parsing context contains number of all
+    variables (including arguments) in all enclosed contexts.
+  */
+  uint m_total_pvars;		
+
   // The maximum sub context's framesizes
-  uint m_psubsize;		
   uint m_csubsize;
   uint m_hsubsize;
   uint m_handlers;		// No. of handlers in this context
@@ -290,8 +346,19 @@ private:
 
   sp_pcontext *m_parent;	// Parent context
 
-  uint m_poffset;		// Variable offset for this context
+  /*
+    m_poffset -- basically, this is an index of the first variable in this
+    parsing context.
+    
+    m_poffset is 0 for root context.
+
+    Since now each variable is stored in separate place, no reuse is done,
+    so m_poffset is different for all enclosed contexts.
+  */
+  uint m_poffset;
+
   uint m_coffset;		// Cursor offset for this context
+
   /*
     Boundary for finding variables in this context. This is the number
     of variables currently "invisible" to default clauses.
@@ -300,7 +367,10 @@ private:
   */
   uint m_pboundary;
 
+  int m_num_case_exprs;
+
   DYNAMIC_ARRAY m_pvar;		// Parameters/variables
+  DYNAMIC_ARRAY m_case_expr_id_lst; /* Stack of CASE expression ids. */
   DYNAMIC_ARRAY m_cond;		// Conditions
   DYNAMIC_ARRAY m_cursor;	// Cursors
   DYNAMIC_ARRAY m_handler;	// Handlers, for checking of duplicates