MDEV-11037 Diagnostics_area refactoring for user defined exceptions

Part 2:

Moving the part of Sql_condition that contain condition items
(such as m_class_origin, m_cursor_name, etc) into a separate
class Sql_condition_items. This allows to remove duplicate code in
different Sql_condition constructors.

Also, introducing new Sql_condition constructors and removing the method
Sql_condition::set(). All code sequences that called an Sql_condition
constructor followed by Sql_condition::set() are now replaced to
the new constructor calls. This gives light performance improvement,
as the relevant members are now initialized only one time.

sql/sp_rcontext.cc

@@ -242,10 +242,9 @@ bool sp_rcontext::handle_sql_condition(THD *thd,
     */
     if (!found_condition)
     {
-      Sql_condition *condition=
-        new (callers_arena->mem_root) Sql_condition(callers_arena->mem_root);
-      condition->set(da, Sql_condition::WARN_LEVEL_ERROR, da->message());
-      found_condition= condition;
+      found_condition=
+        new (callers_arena->mem_root) Sql_condition(callers_arena->mem_root,
+                                                    da, da->message());
     }
   }
   else if (da->current_statement_warn_count())

sql/sql_error.cc

@@ -172,64 +172,6 @@ This file contains the implementation of error and warnings related
     See WL#2111 (Stored Procedures: Implement GET DIAGNOSTICS)
 */
 
-Sql_condition::Sql_condition()
- : Sql_alloc(),
-   m_class_origin((const char*) NULL, 0, & my_charset_utf8_bin),
-   m_subclass_origin((const char*) NULL, 0, & my_charset_utf8_bin),
-   m_constraint_catalog((const char*) NULL, 0, & my_charset_utf8_bin),
-   m_constraint_schema((const char*) NULL, 0, & my_charset_utf8_bin),
-   m_constraint_name((const char*) NULL, 0, & my_charset_utf8_bin),
-   m_catalog_name((const char*) NULL, 0, & my_charset_utf8_bin),
-   m_schema_name((const char*) NULL, 0, & my_charset_utf8_bin),
-   m_table_name((const char*) NULL, 0, & my_charset_utf8_bin),
-   m_column_name((const char*) NULL, 0, & my_charset_utf8_bin),
-   m_cursor_name((const char*) NULL, 0, & my_charset_utf8_bin),
-   m_message_text(),
-   m_mem_root(NULL)
-{
-}
-
-void Sql_condition::init(MEM_ROOT *mem_root)
-{
-  DBUG_ASSERT(mem_root != NULL);
-  DBUG_ASSERT(m_mem_root == NULL);
-  m_mem_root= mem_root;
-}
-
-void Sql_condition::clear()
-{
-  m_class_origin.length(0);
-  m_subclass_origin.length(0);
-  m_constraint_catalog.length(0);
-  m_constraint_schema.length(0);
-  m_constraint_name.length(0);
-  m_catalog_name.length(0);
-  m_schema_name.length(0);
-  m_table_name.length(0);
-  m_column_name.length(0);
-  m_cursor_name.length(0);
-  m_message_text.length(0);
-  m_sql_errno= 0;
-  m_level= Sql_condition::WARN_LEVEL_ERROR;
-}
-
-Sql_condition::Sql_condition(MEM_ROOT *mem_root)
- : Sql_alloc(),
-   m_class_origin((const char*) NULL, 0, & my_charset_utf8_bin),
-   m_subclass_origin((const char*) NULL, 0, & my_charset_utf8_bin),
-   m_constraint_catalog((const char*) NULL, 0, & my_charset_utf8_bin),
-   m_constraint_schema((const char*) NULL, 0, & my_charset_utf8_bin),
-   m_constraint_name((const char*) NULL, 0, & my_charset_utf8_bin),
-   m_catalog_name((const char*) NULL, 0, & my_charset_utf8_bin),
-   m_schema_name((const char*) NULL, 0, & my_charset_utf8_bin),
-   m_table_name((const char*) NULL, 0, & my_charset_utf8_bin),
-   m_column_name((const char*) NULL, 0, & my_charset_utf8_bin),
-   m_cursor_name((const char*) NULL, 0, & my_charset_utf8_bin),
-   m_message_text(),
-   m_mem_root(mem_root)
-{
-  DBUG_ASSERT(mem_root != NULL);
-}
 
 static void copy_string(MEM_ROOT *mem_root, String* dst, const String* src)
 {
@@ -715,12 +657,9 @@ Sql_condition *Warning_info::push_warning(THD *thd,
     if (m_allow_unlimited_warnings ||
         m_warn_list.elements() < thd->variables.max_error_count)
     {
-      cond= new (& m_warn_root) Sql_condition(& m_warn_root);
+      cond= new (& m_warn_root) Sql_condition(& m_warn_root, value, msg);
       if (cond)
-      {
-        cond->set(value, msg);
         m_warn_list.push_back(cond);
-      }
     }
     m_warn_count[(uint) value->get_level()]++;
   }

sql/sql_error.h

@@ -139,6 +139,10 @@ class Sql_state_errno: public Sql_state
   {
     *this= *other;
   }
+  void clear()
+  {
+    m_sql_errno= 0;
+  }
 };
 
 
@@ -177,6 +181,78 @@ class Sql_state_errno_level: public Sql_state_errno
    :Sql_state_errno(sqlerrno, sqlstate),
     m_level(level)
   { }
+  Sql_state_errno_level(const Sql_state_errno &state_errno,
+                         enum_warning_level level)
+   :Sql_state_errno(state_errno),
+    m_level(level)
+  { }
+  void clear()
+  {
+    m_level= WARN_LEVEL_ERROR;
+    Sql_state_errno::clear();
+  }
+};
+
+
+class Sql_condition_items
+{
+protected:
+  /** SQL CLASS_ORIGIN condition item. */
+  String m_class_origin;
+
+  /** SQL SUBCLASS_ORIGIN condition item. */
+  String m_subclass_origin;
+
+  /** SQL CONSTRAINT_CATALOG condition item. */
+  String m_constraint_catalog;
+
+  /** SQL CONSTRAINT_SCHEMA condition item. */
+  String m_constraint_schema;
+
+  /** SQL CONSTRAINT_NAME condition item. */
+  String m_constraint_name;
+
+  /** SQL CATALOG_NAME condition item. */
+  String m_catalog_name;
+
+  /** SQL SCHEMA_NAME condition item. */
+  String m_schema_name;
+
+  /** SQL TABLE_NAME condition item. */
+  String m_table_name;
+
+  /** SQL COLUMN_NAME condition item. */
+  String m_column_name;
+
+  /** SQL CURSOR_NAME condition item. */
+  String m_cursor_name;
+
+  Sql_condition_items()
+   :m_class_origin((const char*) NULL, 0, & my_charset_utf8_bin),
+    m_subclass_origin((const char*) NULL, 0, & my_charset_utf8_bin),
+    m_constraint_catalog((const char*) NULL, 0, & my_charset_utf8_bin),
+    m_constraint_schema((const char*) NULL, 0, & my_charset_utf8_bin),
+    m_constraint_name((const char*) NULL, 0, & my_charset_utf8_bin),
+    m_catalog_name((const char*) NULL, 0, & my_charset_utf8_bin),
+    m_schema_name((const char*) NULL, 0, & my_charset_utf8_bin),
+    m_table_name((const char*) NULL, 0, & my_charset_utf8_bin),
+    m_column_name((const char*) NULL, 0, & my_charset_utf8_bin),
+    m_cursor_name((const char*) NULL, 0, & my_charset_utf8_bin)
+  { }
+
+  void clear()
+  {
+    m_class_origin.length(0);
+    m_subclass_origin.length(0);
+    m_constraint_catalog.length(0);
+    m_constraint_schema.length(0);
+    m_constraint_name.length(0);
+    m_catalog_name.length(0);
+    m_schema_name.length(0);
+    m_table_name.length(0);
+    m_column_name.length(0);
+    m_cursor_name.length(0);
+  }
 };
 
 
@@ -185,7 +261,9 @@ class Sql_state_errno_level: public Sql_state_errno
   A SQL condition can be a completion condition (note, warning),
   or an exception condition (error, not found).
 */
-class Sql_condition : public Sql_alloc, public Sql_state_errno_level
+class Sql_condition : public Sql_alloc,
+                      public Sql_state_errno_level,
+                      public Sql_condition_items
 {
 public:
 
@@ -237,55 +315,74 @@ class Sql_condition : public Sql_alloc, public Sql_state_errno_level
     This constructor is usefull when allocating arrays.
     Note that the init() method should be called to complete the Sql_condition.
   */
-  Sql_condition();
+  Sql_condition()
+   :m_mem_root(NULL)
+  { }
 
   /**
     Complete the Sql_condition initialisation.
     @param mem_root The memory root to use for the condition items
     of this condition
   */
-  void init(MEM_ROOT *mem_root);
+  void init(MEM_ROOT *mem_root)
+  {
+    DBUG_ASSERT(mem_root != NULL);
+    DBUG_ASSERT(m_mem_root == NULL);
+    m_mem_root= mem_root;
+  }
 
   /**
     Constructor.
     @param mem_root The memory root to use for the condition items
     of this condition
   */
-  Sql_condition(MEM_ROOT *mem_root);
-
-  /** Destructor. */
-  ~Sql_condition()
-  {}
-
-  /**
-    Copy optional condition items attributes.
-    @param cond the condition to copy.
-  */
-  void copy_opt_attributes(const Sql_condition *cond);
+  Sql_condition(MEM_ROOT *mem_root)
+   :m_mem_root(mem_root)
+  {
+    DBUG_ASSERT(mem_root != NULL);
+  }
 
   /**
-    Set this condition area with a fixed message text.
-    @param value - the error number and the sql state for this condition.
-    @param level - the error level for this condition.
-    @param msg   - the message text for this condition.
+    Constructor for a fixed message text.
+    @param mem_root - memory root
+    @param value    - the error number and the sql state for this condition
+    @param level    - the error level for this condition
+    @param msg      - the message text for this condition
   */
-  void set(const Sql_state_errno *value,
-           Sql_condition::enum_warning_level level,
-           const char* msg)
+  Sql_condition(MEM_ROOT *mem_root,
+                const Sql_state_errno_level *value,
+                const char *msg)
+   :Sql_state_errno_level(*value),
+    m_mem_root(mem_root)
   {
+    DBUG_ASSERT(mem_root != NULL);
     DBUG_ASSERT(value->get_sql_errno() != 0);
-    DBUG_ASSERT(value->get_sqlstate() != NULL);
     DBUG_ASSERT(msg != NULL);
-    set_condition_value(value);
     set_builtin_message_text(msg);
-    m_level= level;
   }
 
-  void set(const Sql_state_errno_level *cond, const char* msg)
+  Sql_condition(MEM_ROOT *mem_root,
+                const Sql_state_errno *value,
+                const char *msg)
+   :Sql_state_errno_level(*value, Sql_condition::WARN_LEVEL_ERROR),
+    m_mem_root(mem_root)
   {
-    set(cond, cond->get_level(), msg);
+    DBUG_ASSERT(mem_root != NULL);
+    DBUG_ASSERT(value->get_sql_errno() != 0);
+    DBUG_ASSERT(msg != NULL);
+    set_builtin_message_text(msg);
   }
 
+  /** Destructor. */
+  ~Sql_condition()
+  {}
+
+  /**
+    Copy optional condition items attributes.
+    @param cond the condition to copy.
+  */
+  void copy_opt_attributes(const Sql_condition *cond);
+
   /**
     Set the condition message test.
     @param str Message text, expressed in the character set derived from
@@ -310,39 +407,14 @@ class Sql_condition : public Sql_alloc, public Sql_state_errno_level
   /**
     Clear this SQL condition.
   */
-  void clear();
+  void clear()
+  {
+    Sql_state_errno_level::clear();
+    Sql_condition_items::clear();
+    m_message_text.length(0);
+  }
 
 private:
-  /** SQL CLASS_ORIGIN condition item. */
-  String m_class_origin;
-
-  /** SQL SUBCLASS_ORIGIN condition item. */
-  String m_subclass_origin;
-
-  /** SQL CONSTRAINT_CATALOG condition item. */
-  String m_constraint_catalog;
-
-  /** SQL CONSTRAINT_SCHEMA condition item. */
-  String m_constraint_schema;
-
-  /** SQL CONSTRAINT_NAME condition item. */
-  String m_constraint_name;
-
-  /** SQL CATALOG_NAME condition item. */
-  String m_catalog_name;
-
-  /** SQL SCHEMA_NAME condition item. */
-  String m_schema_name;
-
-  /** SQL TABLE_NAME condition item. */
-  String m_table_name;
-
-  /** SQL COLUMN_NAME condition item. */
-  String m_column_name;
-
-  /** SQL CURSOR_NAME condition item. */
-  String m_cursor_name;
-
   /** Message text, expressed in the character set implied by --language. */
   String m_message_text;
 

sql/sql_signal.cc

@@ -427,8 +427,7 @@ bool Sql_cmd_resignal::execute(THD *thd)
     DBUG_RETURN(result);
   }
 
-  Sql_condition signaled_err(thd->mem_root);
-  signaled_err.set(signaled, signaled->message);
+  Sql_condition signaled_err(thd->mem_root, signaled, signaled->message);
 
   if (m_cond)
   {