Adding upstream version 1:10.11.6.upstream/1%10.11.6upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 358 insertions, 0 deletions

diff --git a/sql/sql_prepare.h b/sql/sql_prepare.h
new file mode 100644
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+++ b/sql/sql_prepare.h
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+#ifndef SQL_PREPARE_H
+#define SQL_PREPARE_H
+/* Copyright (c) 1995-2008 MySQL AB, 2009 Sun Microsystems, Inc.
+   Use is subject to license terms.
+
+   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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335  USA */
+
+#include "sql_error.h"
+
+
+#define LAST_STMT_ID 0xFFFFFFFF
+#define STMT_ID_MASK 0x7FFFFFFF
+
+class THD;
+struct LEX;
+
+/**
+  An interface that is used to take an action when
+  the locking module notices that a table version has changed
+  since the last execution. "Table" here may refer to any kind of
+  table -- a base table, a temporary table, a view or an
+  information schema table.
+
+  When we open and lock tables for execution of a prepared
+  statement, we must verify that they did not change
+  since statement prepare. If some table did change, the statement
+  parse tree *may* be no longer valid, e.g. in case it contains
+  optimizations that depend on table metadata.
+
+  This class provides an interface (a method) that is
+  invoked when such a situation takes place.
+  The implementation of the method simply reports an error, but
+  the exact details depend on the nature of the SQL statement.
+
+  At most 1 instance of this class is active at a time, in which
+  case THD::m_reprepare_observer is not NULL.
+
+  @sa check_and_update_table_version() for details of the
+  version tracking algorithm 
+
+  @sa Open_tables_state::m_reprepare_observer for the life cycle
+  of metadata observers.
+*/
+
+class Reprepare_observer
+{
+public:
+  /**
+    Check if a change of metadata is OK. In future
+    the signature of this method may be extended to accept the old
+    and the new versions, but since currently the check is very
+    simple, we only need the THD to report an error.
+  */
+  bool report_error(THD *thd);
+  bool is_invalidated() const { return m_invalidated; }
+  void reset_reprepare_observer() { m_invalidated= FALSE; }
+private:
+  bool m_invalidated;
+};
+
+
+void mysqld_stmt_prepare(THD *thd, const char *packet, uint packet_length);
+void mysqld_stmt_execute(THD *thd, char *packet, uint packet_length);
+void mysqld_stmt_execute_bulk(THD *thd, char *packet, uint packet_length);
+void mysqld_stmt_bulk_execute(THD *thd, char *packet, uint packet_length);
+void mysqld_stmt_close(THD *thd, char *packet);
+void mysql_sql_stmt_prepare(THD *thd);
+void mysql_sql_stmt_execute(THD *thd);
+void mysql_sql_stmt_execute_immediate(THD *thd);
+void mysql_sql_stmt_close(THD *thd);
+void mysqld_stmt_fetch(THD *thd, char *packet, uint packet_length);
+void mysqld_stmt_reset(THD *thd, char *packet);
+void mysql_stmt_get_longdata(THD *thd, char *pos, ulong packet_length);
+void reinit_stmt_before_use(THD *thd, LEX *lex);
+
+my_bool bulk_parameters_iterations(THD *thd);
+my_bool bulk_parameters_set(THD *thd);
+/**
+  Execute a fragment of server code in an isolated context, so that
+  it doesn't leave any effect on THD. THD must have no open tables.
+  The code must not leave any open tables around.
+  The result of execution (if any) is stored in Ed_result.
+*/
+
+class Server_runnable
+{
+public:
+  virtual bool execute_server_code(THD *thd)= 0;
+  virtual ~Server_runnable();
+};
+
+
+/**
+  Execute direct interface.
+
+  @todo Implement support for prelocked mode.
+*/
+
+class Ed_row;
+
+/**
+  Ed_result_set -- a container with result set rows.
+  @todo Implement support for result set metadata and
+  automatic type conversion.
+*/
+
+class Ed_result_set
+{
+public:
+  operator List<Ed_row>&() { return *m_rows; }
+  unsigned int size() const { return m_rows->elements; }
+
+  Ed_result_set(List<Ed_row> *rows_arg, size_t column_count,
+                MEM_ROOT *mem_root_arg);
+
+  /** We don't call member destructors, they all are POD types. */
+  ~Ed_result_set() = default;
+
+  size_t get_field_count() const { return m_column_count; }
+
+  static void *operator new(size_t size, MEM_ROOT *mem_root)
+  { return alloc_root(mem_root, size); }
+  static void operator delete(void *ptr, size_t size) throw ();
+  static void operator delete(void *, MEM_ROOT *){}
+private:
+  Ed_result_set(const Ed_result_set &);        /* not implemented */
+  Ed_result_set &operator=(Ed_result_set &);   /* not implemented */
+private:
+  MEM_ROOT m_mem_root;
+  size_t m_column_count;
+  List<Ed_row> *m_rows;
+  Ed_result_set *m_next_rset;
+  friend class Ed_connection;
+};
+
+
+class Ed_connection
+{
+public:
+  /**
+    Construct a new "execute direct" connection.
+
+    The connection can be used to execute SQL statements.
+    If the connection failed to initialize, the error
+    will be returned on the attempt to execute a statement.
+
+    @pre thd  must have no open tables
+              while the connection is used. However,
+              Ed_connection works okay in LOCK TABLES mode.
+              Other properties of THD, such as the current warning
+              information, errors, etc. do not matter and are
+              preserved by Ed_connection. One thread may have many
+              Ed_connections created for it.
+  */
+  Ed_connection(THD *thd);
+
+  /**
+    Execute one SQL statement.
+
+    Until this method is executed, no other methods of
+    Ed_connection can be used. Life cycle of Ed_connection is:
+
+    Initialized -> a statement has been executed ->
+    look at result, move to next result ->
+    look at result, move to next result ->
+    ...
+    moved beyond the last result == Initialized.
+
+    This method can be called repeatedly. Once it's invoked,
+    results of the previous execution are lost.
+
+    A result of execute_direct() can be either:
+
+    - success, no result set rows. In this case get_field_count()
+    returns 0. This happens after execution of INSERT, UPDATE,
+    DELETE, DROP and similar statements. Some other methods, such
+    as get_affected_rows() can be used to retrieve additional
+    result information.
+
+    - success, there are some result set rows (maybe 0). E.g.
+    happens after SELECT. In this case get_field_count() returns
+    the number of columns in a result set and store_result()
+    can be used to retrieve a result set..
+
+    - an error, methods to retrieve error information can
+    be used.
+
+    @return execution status
+    @retval FALSE  success, use get_field_count()
+                   to determine what to do next.
+    @retval TRUE   error, use get_last_error()
+                   to see the error number.
+  */
+  bool execute_direct(Protocol *p, LEX_STRING sql_text);
+
+  /**
+    Same as the previous, but takes an instance of Server_runnable
+    instead of SQL statement text.
+
+    @return execution status
+      
+    @retval  FALSE  success, use get_field_count() 
+                    if your code fragment is supposed to
+                    return a result set
+    @retval  TRUE   failure
+  */
+  bool execute_direct(Protocol *p, Server_runnable *server_runnable);
+
+  /**
+    Get the number of affected (deleted, updated)
+    rows for the current statement. Can be
+    used for statements with get_field_count() == 0.
+
+    @sa Documentation for C API function
+    mysql_affected_rows().
+  */
+  ulonglong get_affected_rows() const
+  {
+    return m_diagnostics_area.affected_rows();
+  }
+
+  /**
+    Get the last insert id, if any.
+
+    @sa Documentation for mysql_insert_id().
+  */
+  ulonglong get_last_insert_id() const
+  {
+    return m_diagnostics_area.last_insert_id();
+  }
+
+  /**
+    Get the total number of warnings for the last executed
+    statement. Note, that there is only one warning list even
+    if a statement returns multiple results.
+
+    @sa Documentation for C API function
+    mysql_num_warnings().
+  */
+  ulong get_warn_count() const
+  {
+    return m_diagnostics_area.warn_count();
+  }
+
+  /**
+    The following members are only valid if execute_direct()
+    or move_to_next_result() returned an error.
+    They never fail, but if they are called when there is no
+    result, or no error, the result is not defined.
+  */
+  const char *get_last_error() const { return m_diagnostics_area.message(); }
+  unsigned int get_last_errno() const { return m_diagnostics_area.sql_errno(); }
+  const char *get_last_sqlstate() const { return m_diagnostics_area.get_sqlstate(); }
+
+  /**
+    Provided get_field_count() is not 0, this never fails. You don't
+    need to free the result set, this is done automatically when
+    you advance to the next result set or destroy the connection.
+    Not returning const because of List iterator not accepting
+    Should be used when you would like Ed_connection to manage
+    result set memory for you.
+  */
+  Ed_result_set *use_result_set() { return m_current_rset; }
+  /**
+    Provided get_field_count() is not 0, this never fails. You
+    must free the returned result set. This can be called only
+    once after execute_direct().
+    Should be used when you would like to get the results
+    and destroy the connection.
+  */
+  Ed_result_set *store_result_set();
+
+  /**
+    If the query returns multiple results, this method
+    can be checked if there is another result beyond the next
+    one.
+    Never fails.
+  */
+  bool has_next_result() const { return MY_TEST(m_current_rset->m_next_rset); }
+  /**
+    Only valid to call if has_next_result() returned true.
+    Otherwise the result is undefined.
+  */
+  bool move_to_next_result()
+  {
+    m_current_rset= m_current_rset->m_next_rset;
+    return MY_TEST(m_current_rset);
+  }
+
+  ~Ed_connection() { free_old_result(); }
+private:
+  Diagnostics_area m_diagnostics_area;
+  /**
+    Execute direct interface does not support multi-statements, only
+    multi-results. So we never have a situation when we have
+    a mix of result sets and OK or error packets. We either
+    have a single result set, a single error, or a single OK,
+    or we have a series of result sets, followed by an OK or error.
+  */
+  THD *m_thd;
+  Ed_result_set *m_rsets;
+  Ed_result_set *m_current_rset;
+private:
+  void free_old_result();
+  void add_result_set(Ed_result_set *ed_result_set);
+private:
+  Ed_connection(const Ed_connection &);        /* not implemented */
+  Ed_connection &operator=(Ed_connection &);   /* not implemented */
+};
+
+
+/** One result set column. */
+
+struct Ed_column: public LEX_STRING
+{
+  /** Implementation note: destructor for this class is never called. */
+};
+
+
+/** One result set record. */
+
+class Ed_row: public Sql_alloc
+{
+public:
+  const Ed_column &operator[](const unsigned int column_index) const
+  {
+    return *get_column(column_index);
+  }
+  const Ed_column *get_column(const unsigned int column_index) const
+  {
+    DBUG_ASSERT(column_index < size());
+    return m_column_array + column_index;
+  }
+  size_t size() const { return m_column_count; }
+
+  Ed_row(Ed_column *column_array_arg, size_t column_count_arg)
+    :m_column_array(column_array_arg),
+    m_column_count(column_count_arg)
+  {}
+private:
+  Ed_column *m_column_array;
+  size_t m_column_count; /* TODO: change to point to metadata */
+};
+
+extern Atomic_counter<uint32_t> local_connection_thread_count;
+
+#endif // SQL_PREPARE_H