Adding upstream version 1:10.5.12.upstream/1%10.5.12upstream

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

1 files changed, 1876 insertions, 0 deletions

diff --git a/sql/item_strfunc.h b/sql/item_strfunc.h
new file mode 100644
index 00000000..36300e57
--- /dev/null
+++ b/sql/item_strfunc.h
@@ -0,0 +1,1876 @@
+#ifndef ITEM_STRFUNC_INCLUDED
+#define ITEM_STRFUNC_INCLUDED
+
+/*
+   Copyright (c) 2000, 2011, Oracle and/or its affiliates.
+   Copyright (c) 2009, 2019, MariaDB
+
+   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 Street, Fifth Floor, Boston, MA  02110-1335  USA */
+
+
+/* This file defines all string functions */
+
+#ifdef USE_PRAGMA_INTERFACE
+#pragma interface			/* gcc class implementation */
+#endif
+
+extern size_t username_char_length;
+
+class Item_str_func :public Item_func
+{
+protected:
+  /**
+     Sets the result value of the function an empty string, using the current
+     character set. No memory is allocated.
+     @retval A pointer to the str_value member.
+   */
+  virtual String *make_empty_result()
+  {
+    /*
+      Reset string length to an empty string. We don't use str_value.set() as
+      we don't want to free and potentially have to reallocate the buffer
+      for each call.
+    */
+    if (!str_value.is_alloced())
+      str_value.set("", 0, collation.collation); /* Avoid null ptrs */
+    else
+    {
+      str_value.length(0);                      /* Reuse allocated area */
+      str_value.set_charset(collation.collation);
+    }
+    return &str_value; 
+  }
+public:
+  Item_str_func(THD *thd): Item_func(thd) { decimals=NOT_FIXED_DEC; }
+  Item_str_func(THD *thd, Item *a): Item_func(thd, a) {decimals=NOT_FIXED_DEC; }
+  Item_str_func(THD *thd, Item *a, Item *b):
+    Item_func(thd, a, b) { decimals=NOT_FIXED_DEC; }
+  Item_str_func(THD *thd, Item *a, Item *b, Item *c):
+    Item_func(thd, a, b, c) { decimals=NOT_FIXED_DEC; }
+  Item_str_func(THD *thd, Item *a, Item *b, Item *c, Item *d):
+    Item_func(thd, a, b, c, d) { decimals=NOT_FIXED_DEC; }
+  Item_str_func(THD *thd, Item *a, Item *b, Item *c, Item *d, Item* e):
+    Item_func(thd, a, b, c, d, e) { decimals=NOT_FIXED_DEC; }
+  Item_str_func(THD *thd, List<Item> &list):
+    Item_func(thd, list) { decimals=NOT_FIXED_DEC; }
+  longlong val_int();
+  double val_real();
+  my_decimal *val_decimal(my_decimal *);
+  bool get_date(THD *thd, MYSQL_TIME *ltime, date_mode_t fuzzydate)
+  { return get_date_from_string(thd, ltime, fuzzydate); }
+  const Type_handler *type_handler() const { return string_type_handler(); }
+  void left_right_max_length();
+  bool fix_fields(THD *thd, Item **ref);
+};
+
+
+
+/*
+  Functions that return values with ASCII repertoire
+*/
+class Item_str_ascii_func :public Item_str_func
+{
+  String ascii_buf;
+public:
+  Item_str_ascii_func(THD *thd): Item_str_func(thd) {}
+  Item_str_ascii_func(THD *thd, Item *a): Item_str_func(thd, a) {}
+  Item_str_ascii_func(THD *thd, Item *a, Item *b): Item_str_func(thd, a, b) {}
+  Item_str_ascii_func(THD *thd, Item *a, Item *b, Item *c):
+    Item_str_func(thd, a, b, c) {}
+  String *val_str(String *str)
+  {
+    return val_str_from_val_str_ascii(str, &ascii_buf);
+  }
+  String *val_str_ascii(String *)= 0;
+};
+
+
+/**
+  Functions that return a checksum or a hash of the argument,
+  or somehow else encode or decode the argument,
+  returning an ASCII-repertoire string.
+*/
+class Item_str_ascii_checksum_func: public Item_str_ascii_func
+{
+public:
+  Item_str_ascii_checksum_func(THD *thd, Item *a)
+   :Item_str_ascii_func(thd, a) { }
+  Item_str_ascii_checksum_func(THD *thd, Item *a, Item *b)
+   :Item_str_ascii_func(thd, a, b) { }
+  bool eq(const Item *item, bool binary_cmp) const
+  {
+    // Always use binary argument comparison: MD5('x') != MD5('X')
+    return Item_func::eq(item, true);
+  }
+};
+
+
+/**
+  Functions that return a checksum or a hash of the argument,
+  or somehow else encode or decode the argument,
+  returning a binary string.
+*/
+class Item_str_binary_checksum_func: public Item_str_func
+{
+public:
+  Item_str_binary_checksum_func(THD *thd, Item *a)
+   :Item_str_func(thd, a) { }
+  Item_str_binary_checksum_func(THD *thd, Item *a, Item *b)
+   :Item_str_func(thd, a, b) { }
+  bool eq(const Item *item, bool binary_cmp) const
+  {
+    /*
+      Always use binary argument comparison:
+        FROM_BASE64('test') != FROM_BASE64('TEST')
+    */
+    return Item_func::eq(item, true);
+  }
+};
+
+
+class Item_func_md5 :public Item_str_ascii_checksum_func
+{
+public:
+  Item_func_md5(THD *thd, Item *a): Item_str_ascii_checksum_func(thd, a) {}
+  String *val_str_ascii(String *);
+  bool fix_length_and_dec()
+  {
+    fix_length_and_charset(32, default_charset());
+    return FALSE;
+  }
+  const char *func_name() const { return "md5"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_md5>(thd, this); }
+};
+
+
+class Item_func_sha :public Item_str_ascii_checksum_func
+{
+public:
+  Item_func_sha(THD *thd, Item *a): Item_str_ascii_checksum_func(thd, a) {}
+  String *val_str_ascii(String *);    
+  bool fix_length_and_dec();
+  const char *func_name() const { return "sha"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_sha>(thd, this); }
+};
+
+class Item_func_sha2 :public Item_str_ascii_checksum_func
+{
+public:
+  Item_func_sha2(THD *thd, Item *a, Item *b)
+   :Item_str_ascii_checksum_func(thd, a, b) {}
+  String *val_str_ascii(String *);
+  bool fix_length_and_dec();
+  const char *func_name() const { return "sha2"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_sha2>(thd, this); }
+};
+
+class Item_func_to_base64 :public Item_str_ascii_checksum_func
+{
+  String tmp_value;
+public:
+  Item_func_to_base64(THD *thd, Item *a)
+   :Item_str_ascii_checksum_func(thd, a) {}
+  String *val_str_ascii(String *);
+  bool fix_length_and_dec();
+  const char *func_name() const { return "to_base64"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_to_base64>(thd, this); }
+};
+
+class Item_func_from_base64 :public Item_str_binary_checksum_func
+{
+  String tmp_value;
+public:
+  Item_func_from_base64(THD *thd, Item *a)
+   :Item_str_binary_checksum_func(thd, a) { }
+  String *val_str(String *);
+  bool fix_length_and_dec();
+  const char *func_name() const { return "from_base64"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_from_base64>(thd, this); }
+};
+
+#include <my_crypt.h>
+
+class Item_aes_crypt :public Item_str_binary_checksum_func
+{
+  enum { AES_KEY_LENGTH = 128 };
+  void create_key(String *user_key, uchar* key);
+
+protected:
+  int what;
+  String tmp_value;
+public:
+  Item_aes_crypt(THD *thd, Item *a, Item *b)
+   :Item_str_binary_checksum_func(thd, a, b) {}
+  String *val_str(String *);
+};
+
+class Item_func_aes_encrypt :public Item_aes_crypt
+{
+public:
+  Item_func_aes_encrypt(THD *thd, Item *a, Item *b)
+   :Item_aes_crypt(thd, a, b) {}
+  bool fix_length_and_dec();
+  const char *func_name() const { return "aes_encrypt"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_aes_encrypt>(thd, this); }
+};
+
+class Item_func_aes_decrypt :public Item_aes_crypt
+{
+public:
+  Item_func_aes_decrypt(THD *thd, Item *a, Item *b):
+    Item_aes_crypt(thd, a, b) {}
+  bool fix_length_and_dec();
+  const char *func_name() const { return "aes_decrypt"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_aes_decrypt>(thd, this); }
+};
+
+
+class Item_func_concat :public Item_str_func
+{
+protected:
+  String tmp_value;
+  /*
+    Append a non-NULL value to the result.
+    @param [IN]     thd          - The current thread.
+    @param [IN/OUT] res          - The current val_str() return value.
+    @param [IN]     app          - The value to be appended.
+    @retval                      - false on success, true on error
+  */
+  bool append_value(THD *thd, String *res, const String *app);
+  bool realloc_result(String *str, uint length) const;
+public:
+  Item_func_concat(THD *thd, List<Item> &list): Item_str_func(thd, list) {}
+  Item_func_concat(THD *thd, Item *a, Item *b): Item_str_func(thd, a, b) {}
+  String *val_str(String *);
+  bool fix_length_and_dec();
+  const char *func_name() const { return "concat"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_concat>(thd, this); }
+};
+
+
+/*
+  This class handles the || operator in sql_mode=ORACLE.
+  Unlike the traditional MariaDB concat(), it treats NULL arguments as ''.
+*/
+class Item_func_concat_operator_oracle :public Item_func_concat
+{
+public:
+  Item_func_concat_operator_oracle(THD *thd, List<Item> &list)
+   :Item_func_concat(thd, list)
+  { }
+  Item_func_concat_operator_oracle(THD *thd, Item *a, Item *b)
+   :Item_func_concat(thd, a, b)
+  { }
+  String *val_str(String *);
+  const char *func_name() const { return "concat_operator_oracle"; }
+  Item *get_copy(THD *thd)
+  {
+    return get_item_copy<Item_func_concat_operator_oracle>(thd, this);
+  }
+};
+
+
+class Item_func_decode_histogram :public Item_str_func
+{
+public:
+  Item_func_decode_histogram(THD *thd, Item *a, Item *b):
+    Item_str_func(thd, a, b) {}
+  String *val_str(String *);
+  bool fix_length_and_dec()
+  {
+    collation.set(system_charset_info);
+    max_length= MAX_BLOB_WIDTH;
+    maybe_null= 1;
+    return FALSE;
+  }
+  const char *func_name() const { return "decode_histogram"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_decode_histogram>(thd, this); }
+};
+
+class Item_func_concat_ws :public Item_str_func
+{
+  String tmp_value;
+public:
+  Item_func_concat_ws(THD *thd, List<Item> &list): Item_str_func(thd, list) {}
+  String *val_str(String *);
+  bool fix_length_and_dec();
+  const char *func_name() const { return "concat_ws"; }
+  table_map not_null_tables() const { return 0; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_concat_ws>(thd, this); }
+};
+
+class Item_func_reverse :public Item_str_func
+{
+  String tmp_value;
+public:
+  Item_func_reverse(THD *thd, Item *a): Item_str_func(thd, a) {}
+  String *val_str(String *);
+  bool fix_length_and_dec();
+  const char *func_name() const { return "reverse"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_reverse>(thd, this); }
+};
+
+
+class Item_func_replace :public Item_str_func
+{
+  String tmp_value,tmp_value2;
+public:
+  Item_func_replace(THD *thd, Item *org, Item *find, Item *replace):
+    Item_str_func(thd, org, find, replace) {}
+  String *val_str(String *to) { return val_str_internal(to, NULL); };
+  bool fix_length_and_dec();
+  String *val_str_internal(String *str, String *empty_string_for_null);
+  const char *func_name() const { return "replace"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_replace>(thd, this); }
+};
+
+
+class Item_func_replace_oracle :public Item_func_replace
+{
+  String tmp_emtpystr;
+public:
+  Item_func_replace_oracle(THD *thd, Item *org, Item *find, Item *replace):
+    Item_func_replace(thd, org, find, replace) {}
+  String *val_str(String *to) { return val_str_internal(to, &tmp_emtpystr); };
+  const char *func_name() const { return "replace_oracle"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_replace_oracle>(thd, this); }
+};
+
+
+class Item_func_regexp_replace :public Item_str_func
+{
+  Regexp_processor_pcre re;
+  bool append_replacement(String *str,
+                          const LEX_CSTRING *source,
+                          const LEX_CSTRING *replace);
+public:
+  Item_func_regexp_replace(THD *thd, Item *a, Item *b, Item *c):
+    Item_str_func(thd, a, b, c)
+    {}
+  void cleanup()
+  {
+    DBUG_ENTER("Item_func_regexp_replace::cleanup");
+    Item_str_func::cleanup();
+    re.cleanup();
+    DBUG_VOID_RETURN;
+  }
+  String *val_str(String *str);
+  bool fix_length_and_dec();
+  const char *func_name() const { return "regexp_replace"; }
+  Item *get_copy(THD *thd) { return 0;}
+};
+
+
+class Item_func_regexp_substr :public Item_str_func
+{
+  Regexp_processor_pcre re;
+public:
+  Item_func_regexp_substr(THD *thd, Item *a, Item *b):
+    Item_str_func(thd, a, b)
+    {}
+  void cleanup()
+  {
+    DBUG_ENTER("Item_func_regexp_substr::cleanup");
+    Item_str_func::cleanup();
+    re.cleanup();
+    DBUG_VOID_RETURN;
+  }
+  String *val_str(String *str);
+  bool fix_length_and_dec();
+  const char *func_name() const { return "regexp_substr"; }
+  Item *get_copy(THD *thd) { return 0; }
+};
+
+
+class Item_func_insert :public Item_str_func
+{
+  String tmp_value;
+public:
+  Item_func_insert(THD *thd, Item *org, Item *start, Item *length,
+                   Item *new_str):
+    Item_str_func(thd, org, start, length, new_str) {}
+  String *val_str(String *);
+  bool fix_length_and_dec();
+  const char *func_name() const { return "insert"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_insert>(thd, this); }
+};
+
+
+class Item_str_conv :public Item_str_func
+{
+protected:
+  uint multiply;
+  my_charset_conv_case converter;
+  String tmp_value;
+public:
+  Item_str_conv(THD *thd, Item *item): Item_str_func(thd, item) {}
+  String *val_str(String *);
+};
+
+
+class Item_func_lcase :public Item_str_conv
+{
+public:
+  Item_func_lcase(THD *thd, Item *item): Item_str_conv(thd, item) {}
+  const char *func_name() const { return "lcase"; }
+  bool fix_length_and_dec();
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_lcase>(thd, this); }
+};
+
+class Item_func_ucase :public Item_str_conv
+{
+public:
+  Item_func_ucase(THD *thd, Item *item): Item_str_conv(thd, item) {}
+  const char *func_name() const { return "ucase"; }
+  bool fix_length_and_dec();
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_ucase>(thd, this); }
+};
+
+
+class Item_func_left :public Item_str_func
+{
+  String tmp_value;
+public:
+  Item_func_left(THD *thd, Item *a, Item *b): Item_str_func(thd, a, b) {}
+  String *val_str(String *);
+  bool fix_length_and_dec();
+  const char *func_name() const { return "left"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_left>(thd, this); }
+};
+
+
+class Item_func_right :public Item_str_func
+{
+  String tmp_value;
+public:
+  Item_func_right(THD *thd, Item *a, Item *b): Item_str_func(thd, a, b) {}
+  String *val_str(String *);
+  bool fix_length_and_dec();
+  const char *func_name() const { return "right"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_right>(thd, this); }
+};
+
+
+class Item_func_substr :public Item_str_func
+{
+  String tmp_value;
+protected:
+  virtual longlong get_position() { return args[1]->val_int(); }
+public:
+  Item_func_substr(THD *thd, Item *a, Item *b): Item_str_func(thd, a, b) {}
+  Item_func_substr(THD *thd, Item *a, Item *b, Item *c):
+    Item_str_func(thd, a, b, c) {}
+  String *val_str(String *);
+  bool fix_length_and_dec();
+  const char *func_name() const { return "substr"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_substr>(thd, this); }
+};
+
+class Item_func_substr_oracle :public Item_func_substr
+{
+protected:
+  longlong get_position()
+  { longlong pos= args[1]->val_int(); return pos == 0 ? 1 : pos; }
+  String *make_empty_result()
+  { null_value= 1; return NULL; }
+public:
+  Item_func_substr_oracle(THD *thd, Item *a, Item *b):
+    Item_func_substr(thd, a, b) {}
+  Item_func_substr_oracle(THD *thd, Item *a, Item *b, Item *c):
+    Item_func_substr(thd, a, b, c) {}
+  bool fix_length_and_dec()
+  {
+    bool res= Item_func_substr::fix_length_and_dec();
+    maybe_null= true;
+    return res;
+  }
+  const char *func_name() const { return "substr_oracle"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_substr_oracle>(thd, this); }
+};
+
+class Item_func_substr_index :public Item_str_func
+{
+  String tmp_value;
+public:
+  Item_func_substr_index(THD *thd, Item *a,Item *b,Item *c):
+    Item_str_func(thd, a, b, c) {}
+  String *val_str(String *);
+  bool fix_length_and_dec();
+  const char *func_name() const { return "substring_index"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_substr_index>(thd, this); }
+
+};
+
+
+class Item_func_trim :public Item_str_func
+{
+protected:
+  String tmp_value;
+  String remove;
+  String *trimmed_value(String *res, uint32 offset, uint32 length)
+  {
+    if (length == 0)
+      return make_empty_result();
+
+    tmp_value.set(*res, offset, length);
+    /*
+      Make sure to return correct charset and collation:
+      TRIM(0x000000 FROM _ucs2 0x0061)
+      should set charset to "binary" rather than to "ucs2".
+    */
+    tmp_value.set_charset(collation.collation);
+    return &tmp_value;
+  }
+  String *non_trimmed_value(String *res)
+  {
+    return trimmed_value(res, 0, res->length());
+  }
+  virtual const char *func_name_ext() const { return ""; }
+public:
+  Item_func_trim(THD *thd, Item *a, Item *b): Item_str_func(thd, a, b) {}
+  Item_func_trim(THD *thd, Item *a): Item_str_func(thd, a) {}
+  Sql_mode_dependency value_depends_on_sql_mode() const;
+  String *val_str(String *);
+  bool fix_length_and_dec();
+  const char *func_name() const { return "trim"; }
+  void print(String *str, enum_query_type query_type);
+  virtual const char *mode_name() const { return "both"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_trim>(thd, this); }
+};
+
+
+class Item_func_trim_oracle :public Item_func_trim
+{
+protected:
+  String *make_empty_result()
+  { null_value= 1; return NULL; }
+  const char *func_name_ext() const { return "_oracle"; }
+public:
+  Item_func_trim_oracle(THD *thd, Item *a, Item *b):
+    Item_func_trim(thd, a, b) {}
+  Item_func_trim_oracle(THD *thd, Item *a): Item_func_trim(thd, a) {}
+  const char *func_name() const { return "trim_oracle"; }
+  bool fix_length_and_dec()
+  {
+    bool res= Item_func_trim::fix_length_and_dec();
+    maybe_null= true;
+    return res;
+  }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_trim_oracle>(thd, this); }
+};
+
+
+class Item_func_ltrim :public Item_func_trim
+{
+public:
+  Item_func_ltrim(THD *thd, Item *a, Item *b): Item_func_trim(thd, a, b) {}
+  Item_func_ltrim(THD *thd, Item *a): Item_func_trim(thd, a) {}
+  Sql_mode_dependency value_depends_on_sql_mode() const
+  {
+    return Item_func::value_depends_on_sql_mode();
+  }
+  String *val_str(String *);
+  const char *func_name() const { return "ltrim"; }
+  const char *mode_name() const { return "leading"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_ltrim>(thd, this); }
+};
+
+
+class Item_func_ltrim_oracle :public Item_func_ltrim
+{
+protected:
+  String *make_empty_result()
+  { null_value= 1; return NULL; }
+  const char *func_name_ext() const { return "_oracle"; }
+public:
+  Item_func_ltrim_oracle(THD *thd, Item *a, Item *b):
+    Item_func_ltrim(thd, a, b) {}
+  Item_func_ltrim_oracle(THD *thd, Item *a): Item_func_ltrim(thd, a) {}
+  const char *func_name() const { return "ltrim_oracle"; }
+  bool fix_length_and_dec()
+  {
+    bool res= Item_func_ltrim::fix_length_and_dec();
+    maybe_null= true;
+    return res;
+  }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_ltrim_oracle>(thd, this); }
+};
+
+
+class Item_func_rtrim :public Item_func_trim
+{
+public:
+  Item_func_rtrim(THD *thd, Item *a, Item *b): Item_func_trim(thd, a, b) {}
+  Item_func_rtrim(THD *thd, Item *a): Item_func_trim(thd, a) {}
+  String *val_str(String *);
+  const char *func_name() const { return "rtrim"; }
+  const char *mode_name() const { return "trailing"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_rtrim>(thd, this); }
+};
+
+
+class Item_func_rtrim_oracle :public Item_func_rtrim
+{
+protected:
+  String *make_empty_result()
+  { null_value= 1; return NULL; }
+  const char *func_name_ext() const { return "_oracle"; }
+public:
+  Item_func_rtrim_oracle(THD *thd, Item *a, Item *b):
+    Item_func_rtrim(thd, a, b) {}
+  Item_func_rtrim_oracle(THD *thd, Item *a): Item_func_rtrim(thd, a) {}
+  const char *func_name() const { return "rtrim_oracle"; }
+  bool fix_length_and_dec()
+  {
+    bool res= Item_func_rtrim::fix_length_and_dec();
+    maybe_null= true;
+    return res;
+  }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_rtrim_oracle>(thd, this); }
+};
+
+/*
+  Item_func_password -- new (4.1.1) PASSWORD() function implementation.
+  Returns strcat('*', octet2hex(sha1(sha1(password)))). '*' stands for new
+  password format, sha1(sha1(password) is so-called hash_stage2 value.
+  Length of returned string is always 41 byte. To find out how entire
+  authentication procedure works, see comments in password.c.
+*/
+
+class Item_func_password :public Item_str_ascii_checksum_func
+{
+public:
+  enum PW_Alg {OLD, NEW};
+private:
+  char tmp_value[SCRAMBLED_PASSWORD_CHAR_LENGTH+1]; 
+  enum PW_Alg alg;
+  bool deflt;
+public:
+  Item_func_password(THD *thd, Item *a):
+    Item_str_ascii_checksum_func(thd, a), alg(NEW), deflt(1) {}
+  Item_func_password(THD *thd, Item *a, PW_Alg al):
+    Item_str_ascii_checksum_func(thd, a), alg(al), deflt(0) {}
+  String *val_str_ascii(String *str);
+  bool fix_fields(THD *thd, Item **ref);
+  bool fix_length_and_dec()
+  {
+    fix_length_and_charset((alg == 1 ?
+                            SCRAMBLED_PASSWORD_CHAR_LENGTH :
+                            SCRAMBLED_PASSWORD_CHAR_LENGTH_323),
+                           default_charset());
+    return FALSE;
+  }
+  const char *func_name() const { return ((deflt || alg == 1) ?
+                                          "password" : "old_password"); }
+  static char *alloc(THD *thd, const char *password, size_t pass_len,
+                     enum PW_Alg al);
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_password>(thd, this); }
+};
+
+
+
+class Item_func_des_encrypt :public Item_str_binary_checksum_func
+{
+  String tmp_value,tmp_arg;
+public:
+  Item_func_des_encrypt(THD *thd, Item *a)
+   :Item_str_binary_checksum_func(thd, a) {}
+  Item_func_des_encrypt(THD *thd, Item *a, Item *b)
+   :Item_str_binary_checksum_func(thd, a, b) {}
+  String *val_str(String *);
+  bool fix_length_and_dec()
+  {
+    maybe_null=1;
+    /* 9 = MAX ((8- (arg_len % 8)) + 1) */
+    max_length = args[0]->max_length + 9;
+    return FALSE;
+  }
+  const char *func_name() const { return "des_encrypt"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_des_encrypt>(thd, this); }
+};
+
+class Item_func_des_decrypt :public Item_str_binary_checksum_func
+{
+  String tmp_value;
+public:
+  Item_func_des_decrypt(THD *thd, Item *a)
+   :Item_str_binary_checksum_func(thd, a) {}
+  Item_func_des_decrypt(THD *thd, Item *a, Item *b)
+   :Item_str_binary_checksum_func(thd, a, b) {}
+  String *val_str(String *);
+  bool fix_length_and_dec()
+  {
+    maybe_null=1;
+    /* 9 = MAX ((8- (arg_len % 8)) + 1) */
+    max_length= args[0]->max_length;
+    if (max_length >= 9U)
+      max_length-= 9U;
+    return FALSE;
+  }
+  const char *func_name() const { return "des_decrypt"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_des_decrypt>(thd, this); }
+};
+
+
+/**
+  QQ: Item_func_encrypt should derive from Item_str_ascii_checksum_func.
+  However, it should be fixed to handle UCS2, UTF16, UTF32 properly first,
+  as the underlying crypt() call expects a null-terminated input string.
+*/
+class Item_func_encrypt :public Item_str_binary_checksum_func
+{
+  String tmp_value;
+
+  /* Encapsulate common constructor actions */
+  void constructor_helper()
+  {
+    collation.set(&my_charset_bin);
+  }
+public:
+  Item_func_encrypt(THD *thd, Item *a): Item_str_binary_checksum_func(thd, a)
+  {
+    constructor_helper();
+  }
+  Item_func_encrypt(THD *thd, Item *a, Item *b)
+   :Item_str_binary_checksum_func(thd, a, b)
+  {
+    constructor_helper();
+  }
+  String *val_str(String *);
+  bool fix_length_and_dec() { maybe_null=1; max_length = 13; return FALSE; }
+  const char *func_name() const { return "encrypt"; }
+  bool check_vcol_func_processor(void *arg)
+  {
+    return FALSE;
+  }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_encrypt>(thd, this); }
+};
+
+#include "sql_crypt.h"
+
+
+class Item_func_encode :public Item_str_binary_checksum_func
+{
+private:
+  /** Whether the PRNG has already been seeded. */
+  bool seeded;
+protected:
+  SQL_CRYPT sql_crypt;
+public:
+  Item_func_encode(THD *thd, Item *a, Item *seed_arg):
+    Item_str_binary_checksum_func(thd, a, seed_arg) {}
+  String *val_str(String *);
+  bool fix_length_and_dec();
+  const char *func_name() const { return "encode"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_encode>(thd, this); }
+protected:
+  virtual void crypto_transform(String *);
+private:
+  /** Provide a seed for the PRNG sequence. */
+  bool seed();
+};
+
+
+class Item_func_decode :public Item_func_encode
+{
+public:
+  Item_func_decode(THD *thd, Item *a, Item *seed_arg): Item_func_encode(thd, a, seed_arg) {}
+  const char *func_name() const { return "decode"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_decode>(thd, this); }
+protected:
+  void crypto_transform(String *);
+};
+
+
+class Item_func_sysconst :public Item_str_func
+{
+public:
+  Item_func_sysconst(THD *thd): Item_str_func(thd)
+  { collation.set(system_charset_info,DERIVATION_SYSCONST); }
+  Item *safe_charset_converter(THD *thd, CHARSET_INFO *tocs);
+  /*
+    Used to create correct Item name in new converted item in
+    safe_charset_converter, return string representation of this function
+    call
+  */
+  virtual const char *fully_qualified_func_name() const = 0;
+  bool check_vcol_func_processor(void *arg)
+  {
+    return mark_unsupported_function(fully_qualified_func_name(), arg,
+                                     VCOL_SESSION_FUNC);
+  }
+  bool const_item() const;
+};
+
+
+class Item_func_database :public Item_func_sysconst
+{
+public:
+  Item_func_database(THD *thd): Item_func_sysconst(thd) {}
+  String *val_str(String *);
+  bool fix_length_and_dec()
+  {
+    max_length= MAX_FIELD_NAME * system_charset_info->mbmaxlen;
+    maybe_null=1;
+    return FALSE;
+  }
+  const char *func_name() const { return "database"; }
+  const char *fully_qualified_func_name() const { return "database()"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_database>(thd, this); }
+};
+
+
+class Item_func_sqlerrm :public Item_func_sysconst
+{
+public:
+  Item_func_sqlerrm(THD *thd): Item_func_sysconst(thd) {}
+  String *val_str(String *);
+  const char *func_name() const { return "SQLERRM"; }
+  const char *fully_qualified_func_name() const { return "SQLERRM"; }
+  void print(String *str, enum_query_type query_type)
+  {
+    str->append(func_name());
+  }
+  bool fix_length_and_dec()
+  {
+    max_length= 512 * system_charset_info->mbmaxlen;
+    null_value= maybe_null= false;
+    return FALSE;
+  }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_sqlerrm>(thd, this); }
+};
+
+
+class Item_func_user :public Item_func_sysconst
+{
+protected:
+  bool init (const char *user, const char *host);
+
+public:
+  Item_func_user(THD *thd): Item_func_sysconst(thd)
+  {
+    str_value.set("", 0, system_charset_info);
+  }
+  String *val_str(String *)
+  {
+    DBUG_ASSERT(fixed == 1);
+    return (null_value ? 0 : &str_value);
+  }
+  bool fix_fields(THD *thd, Item **ref);
+  bool fix_length_and_dec()
+  {
+    max_length= (uint32) (username_char_length +
+                 HOSTNAME_LENGTH + 1) * SYSTEM_CHARSET_MBMAXLEN;
+    return FALSE;
+  }
+  const char *func_name() const { return "user"; }
+  const char *fully_qualified_func_name() const { return "user()"; }
+  int save_in_field(Field *field, bool no_conversions)
+  {
+    return save_str_value_in_field(field, &str_value);
+  }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_user>(thd, this); }
+};
+
+
+class Item_func_current_user :public Item_func_user
+{
+  Name_resolution_context *context;
+
+public:
+  Item_func_current_user(THD *thd, Name_resolution_context *context_arg):
+    Item_func_user(thd), context(context_arg) {}
+  bool fix_fields(THD *thd, Item **ref);
+  const char *func_name() const { return "current_user"; }
+  const char *fully_qualified_func_name() const { return "current_user()"; }
+  bool check_vcol_func_processor(void *arg)
+  {
+    context= 0;
+    return mark_unsupported_function(fully_qualified_func_name(), arg,
+                                     VCOL_SESSION_FUNC);
+  }
+};
+
+
+class Item_func_current_role :public Item_func_sysconst
+{
+  Name_resolution_context *context;
+
+public:
+  Item_func_current_role(THD *thd, Name_resolution_context *context_arg):
+    Item_func_sysconst(thd), context(context_arg) {}
+  bool fix_fields(THD *thd, Item **ref);
+  bool fix_length_and_dec()
+  {
+    max_length= (uint32) username_char_length * SYSTEM_CHARSET_MBMAXLEN;
+    return FALSE;
+  }
+  int save_in_field(Field *field, bool no_conversions)
+  { return save_str_value_in_field(field, &str_value); }
+  const char *func_name() const { return "current_role"; }
+  const char *fully_qualified_func_name() const { return "current_role()"; }
+  String *val_str(String *)
+  {
+    DBUG_ASSERT(fixed == 1);
+    return null_value ? NULL : &str_value;
+  }
+  bool check_vcol_func_processor(void *arg)
+  {
+
+    context= 0;
+    return mark_unsupported_function(fully_qualified_func_name(), arg,
+                                     VCOL_SESSION_FUNC);
+  }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_current_role>(thd, this); }
+};
+
+
+class Item_func_soundex :public Item_str_func
+{
+  String tmp_value;
+public:
+  Item_func_soundex(THD *thd, Item *a): Item_str_func(thd, a) {}
+  String *val_str(String *);
+  bool fix_length_and_dec();
+  const char *func_name() const { return "soundex"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_soundex>(thd, this); }
+};
+
+
+class Item_func_elt :public Item_str_func
+{
+public:
+  Item_func_elt(THD *thd, List<Item> &list): Item_str_func(thd, list) {}
+  double val_real();
+  longlong val_int();
+  String *val_str(String *str);
+  bool fix_length_and_dec();
+  const char *func_name() const { return "elt"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_elt>(thd, this); }
+};
+
+
+class Item_func_make_set :public Item_str_func
+{
+  String tmp_str;
+
+public:
+  Item_func_make_set(THD *thd, List<Item> &list): Item_str_func(thd, list) {}
+  String *val_str(String *str);
+  bool fix_length_and_dec();
+  const char *func_name() const { return "make_set"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_make_set>(thd, this); }
+};
+
+
+class Item_func_format :public Item_str_ascii_func
+{
+  const MY_LOCALE *locale;
+public:
+  Item_func_format(THD *thd, Item *org, Item *dec):
+    Item_str_ascii_func(thd, org, dec) {}
+  Item_func_format(THD *thd, Item *org, Item *dec, Item *lang):
+    Item_str_ascii_func(thd, org, dec, lang) {}
+
+  String *val_str_ascii(String *);
+  bool fix_length_and_dec();
+  const char *func_name() const { return "format"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_format>(thd, this); }
+};
+
+
+class Item_func_char :public Item_str_func
+{
+public:
+  Item_func_char(THD *thd, List<Item> &list): Item_str_func(thd, list)
+  { collation.set(&my_charset_bin); }
+  Item_func_char(THD *thd, List<Item> &list, CHARSET_INFO *cs):
+    Item_str_func(thd, list)
+  { collation.set(cs); }
+  Item_func_char(THD *thd, Item *arg1, CHARSET_INFO *cs):
+    Item_str_func(thd, arg1)
+  { collation.set(cs); }
+  String *val_str(String *);
+  void append_char(String * str, int32 num);
+  bool fix_length_and_dec()
+  {
+    max_length= arg_count * 4;
+    return FALSE;
+  }
+  const char *func_name() const { return "char"; }
+  void print(String *str, enum_query_type query_type);
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_char>(thd, this); }
+};
+
+class Item_func_chr :public Item_func_char
+{
+public:
+  Item_func_chr(THD *thd, Item *arg1, CHARSET_INFO *cs):
+    Item_func_char(thd, arg1, cs) {}
+  String *val_str(String *);
+  bool fix_length_and_dec()
+  {
+    max_length= 4;
+    return FALSE;
+  }
+  const char *func_name() const { return "chr"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_chr>(thd, this); }
+};
+
+class Item_func_repeat :public Item_str_func
+{
+  String tmp_value;
+public:
+  Item_func_repeat(THD *thd, Item *arg1, Item *arg2):
+    Item_str_func(thd, arg1, arg2) {}
+  String *val_str(String *);
+  bool fix_length_and_dec();
+  const char *func_name() const { return "repeat"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_repeat>(thd, this); }
+};
+
+
+class Item_func_space :public Item_str_func
+{
+public:
+  Item_func_space(THD *thd, Item *arg1): Item_str_func(thd, arg1) {}
+  String *val_str(String *);
+  bool fix_length_and_dec();
+  const char *func_name() const { return "space"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_space>(thd, this); }
+};
+
+
+class Item_func_binlog_gtid_pos :public Item_str_func
+{
+public:
+  Item_func_binlog_gtid_pos(THD *thd, Item *arg1, Item *arg2):
+    Item_str_func(thd, arg1, arg2) {}
+  String *val_str(String *);
+  bool fix_length_and_dec();
+  const char *func_name() const { return "binlog_gtid_pos"; }
+  bool check_vcol_func_processor(void *arg)
+  {
+    return mark_unsupported_function(func_name(), "()", arg, VCOL_IMPOSSIBLE);
+  }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_binlog_gtid_pos>(thd, this); }
+};
+
+
+class Item_func_pad: public Item_str_func
+{
+protected:
+  String tmp_value, pad_str;
+public:
+  Item_func_pad(THD *thd, Item *arg1, Item *arg2, Item *arg3):
+    Item_str_func(thd, arg1, arg2, arg3) {}
+  Item_func_pad(THD *thd, Item *arg1, Item *arg2):
+    Item_str_func(thd, arg1, arg2) {}
+  bool fix_length_and_dec();
+};
+
+
+class Item_func_rpad :public Item_func_pad
+{
+public:
+  Item_func_rpad(THD *thd, Item *arg1, Item *arg2, Item *arg3):
+    Item_func_pad(thd, arg1, arg2, arg3) {}
+  Item_func_rpad(THD *thd, Item *arg1, Item *arg2):
+    Item_func_pad(thd, arg1, arg2) {}
+  String *val_str(String *);
+  const char *func_name() const { return "rpad"; }
+  Sql_mode_dependency value_depends_on_sql_mode() const;
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_rpad>(thd, this); }
+};
+
+
+class Item_func_rpad_oracle :public Item_func_rpad
+{
+  String *make_empty_result()
+  { null_value= 1; return NULL; }
+public:
+  Item_func_rpad_oracle(THD *thd, Item *arg1, Item *arg2, Item *arg3):
+    Item_func_rpad(thd, arg1, arg2, arg3) {}
+  Item_func_rpad_oracle(THD *thd, Item *arg1, Item *arg2):
+    Item_func_rpad(thd, arg1, arg2) {}
+  bool fix_length_and_dec()
+  {
+    bool res= Item_func_rpad::fix_length_and_dec();
+    maybe_null= true;
+    return res;
+  }
+  const char *func_name() const { return "rpad_oracle"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_rpad_oracle>(thd, this); }
+};
+
+
+class Item_func_lpad :public Item_func_pad
+{
+public:
+  Item_func_lpad(THD *thd, Item *arg1, Item *arg2, Item *arg3):
+    Item_func_pad(thd, arg1, arg2, arg3) {}
+  Item_func_lpad(THD *thd, Item *arg1, Item *arg2):
+    Item_func_pad(thd, arg1, arg2) {}
+  String *val_str(String *);
+  const char *func_name() const { return "lpad"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_lpad>(thd, this); }
+};
+
+
+class Item_func_lpad_oracle :public Item_func_lpad
+{
+  String *make_empty_result()
+  { null_value= 1; return NULL; }
+public:
+  Item_func_lpad_oracle(THD *thd, Item *arg1, Item *arg2, Item *arg3):
+    Item_func_lpad(thd, arg1, arg2, arg3) {}
+  Item_func_lpad_oracle(THD *thd, Item *arg1, Item *arg2):
+    Item_func_lpad(thd, arg1, arg2) {}
+  bool fix_length_and_dec()
+  {
+    bool res= Item_func_lpad::fix_length_and_dec();
+    maybe_null= true;
+    return res;
+  }
+  const char *func_name() const { return "lpad_oracle"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_lpad_oracle>(thd, this); }
+};
+
+
+class Item_func_conv :public Item_str_func
+{
+public:
+  Item_func_conv(THD *thd, Item *a, Item *b, Item *c):
+    Item_str_func(thd, a, b, c) {}
+  const char *func_name() const { return "conv"; }
+  String *val_str(String *);
+  bool fix_length_and_dec()
+  {
+    collation.set(default_charset());
+    fix_char_length(64);
+    maybe_null= 1;
+    return FALSE;
+  }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_conv>(thd, this); }
+};
+
+
+class Item_func_hex :public Item_str_ascii_checksum_func
+{
+protected:
+  String tmp_value;
+  /*
+    Calling arg[0]->type_handler() can be expensive on every row.
+    It's a virtual method, and in case if args[0] is a complex Item,
+    its type_handler() can call more virtual methods.
+    So let's cache it during fix_length_and_dec().
+  */
+  const Type_handler *m_arg0_type_handler;
+public:
+  Item_func_hex(THD *thd, Item *a):
+    Item_str_ascii_checksum_func(thd, a), m_arg0_type_handler(NULL) {}
+  const char *func_name() const { return "hex"; }
+  String *val_str_ascii_from_val_int(String *str);
+  String *val_str_ascii_from_val_real(String *str);
+  String *val_str_ascii_from_val_str(String *str);
+  String *val_str_ascii(String *str)
+  {
+    DBUG_ASSERT(fixed);
+    return m_arg0_type_handler->Item_func_hex_val_str_ascii(this, str);
+  }
+  bool fix_length_and_dec()
+  {
+    collation.set(default_charset(), DERIVATION_COERCIBLE, MY_REPERTOIRE_ASCII);
+    decimals=0;
+    fix_char_length(args[0]->max_length * 2);
+    m_arg0_type_handler= args[0]->type_handler();
+    return FALSE;
+  }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_hex>(thd, this); }
+};
+
+class Item_func_unhex :public Item_str_func
+{
+  String tmp_value;
+public:
+  Item_func_unhex(THD *thd, Item *a): Item_str_func(thd, a)
+  {
+    /* there can be bad hex strings */
+    maybe_null= 1;
+  }
+  const char *func_name() const { return "unhex"; }
+  String *val_str(String *);
+  bool fix_length_and_dec()
+  {
+    collation.set(&my_charset_bin);
+    decimals=0;
+    max_length=(1+args[0]->max_length)/2;
+    return FALSE;
+  }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_unhex>(thd, this); }
+};
+
+
+#ifndef DBUG_OFF
+class Item_func_like_range :public Item_str_func
+{
+protected:
+  String min_str;
+  String max_str;
+  const bool is_min;
+public:
+  Item_func_like_range(THD *thd, Item *a, Item *b, bool is_min_arg):
+    Item_str_func(thd, a, b), is_min(is_min_arg)
+  { maybe_null= 1; }
+  String *val_str(String *);
+  bool fix_length_and_dec()
+  {
+    collation.set(args[0]->collation);
+    decimals=0;
+    max_length= MAX_BLOB_WIDTH;
+    return FALSE;
+  }
+};
+
+
+class Item_func_like_range_min :public Item_func_like_range
+{
+public:
+  Item_func_like_range_min(THD *thd, Item *a, Item *b):
+    Item_func_like_range(thd, a, b, true) { }
+  const char *func_name() const { return "like_range_min"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_like_range_min>(thd, this); }
+};
+
+
+class Item_func_like_range_max :public Item_func_like_range
+{
+public:
+  Item_func_like_range_max(THD *thd, Item *a, Item *b):
+    Item_func_like_range(thd, a, b, false) { }
+  const char *func_name() const { return "like_range_max"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_like_range_max>(thd, this); }
+};
+#endif
+
+
+class Item_func_binary :public Item_str_func
+{
+public:
+  Item_func_binary(THD *thd, Item *a): Item_str_func(thd, a) {}
+  String *val_str(String *a)
+  {
+    DBUG_ASSERT(fixed == 1);
+    String *tmp=args[0]->val_str(a);
+    null_value=args[0]->null_value;
+    if (tmp)
+      tmp->set_charset(&my_charset_bin);
+    return tmp;
+  }
+  bool fix_length_and_dec()
+  {
+    collation.set(&my_charset_bin);
+    max_length=args[0]->max_length;
+    return FALSE;
+  }
+  void print(String *str, enum_query_type query_type);
+  const char *func_name() const { return "cast_as_binary"; }
+  bool need_parentheses_in_default() { return true; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_binary>(thd, this); }
+};
+
+
+class Item_load_file :public Item_str_func
+{
+  String tmp_value;
+public:
+  Item_load_file(THD *thd, Item *a): Item_str_func(thd, a) {}
+  String *val_str(String *);
+  const char *func_name() const { return "load_file"; }
+  bool fix_length_and_dec()
+  {
+    collation.set(&my_charset_bin, DERIVATION_COERCIBLE);
+    maybe_null=1;
+    max_length=MAX_BLOB_WIDTH;
+    return FALSE;
+  }
+  bool check_vcol_func_processor(void *arg)
+  {
+    return mark_unsupported_function(func_name(), "()", arg, VCOL_IMPOSSIBLE);
+  }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_load_file>(thd, this); }
+};
+
+
+class Item_func_export_set: public Item_str_func
+{
+ public:
+  Item_func_export_set(THD *thd, Item *a, Item *b, Item* c):
+    Item_str_func(thd, a, b, c) {}
+  Item_func_export_set(THD *thd, Item *a, Item *b, Item* c, Item* d):
+    Item_str_func(thd, a, b, c, d) {}
+  Item_func_export_set(THD *thd, Item *a, Item *b, Item* c, Item* d, Item* e):
+    Item_str_func(thd, a, b, c, d, e) {}
+  String  *val_str(String *str);
+  bool fix_length_and_dec();
+  const char *func_name() const { return "export_set"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_export_set>(thd, this); }
+};
+
+
+class Item_func_quote :public Item_str_func
+{
+  String tmp_value;
+public:
+  Item_func_quote(THD *thd, Item *a): Item_str_func(thd, a) {}
+  const char *func_name() const { return "quote"; }
+  String *val_str(String *);
+  bool fix_length_and_dec()
+  {
+    collation.set(args[0]->collation);
+    ulonglong max_result_length= (ulonglong) args[0]->max_length * 2 +
+                                  2 * collation.collation->mbmaxlen;
+    max_length= (uint32) MY_MIN(max_result_length, MAX_BLOB_WIDTH);
+    return FALSE;
+  }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_quote>(thd, this); }
+};
+
+class Item_func_conv_charset :public Item_str_func
+{
+  bool use_cached_value;
+  String tmp_value;
+public:
+  bool safe;
+  Item_func_conv_charset(THD *thd, Item *a, CHARSET_INFO *cs):
+    Item_str_func(thd, a)
+  {
+    collation.set(cs, DERIVATION_IMPLICIT);
+    use_cached_value= 0; safe= 0;
+  }
+  Item_func_conv_charset(THD *thd, Item *a, CHARSET_INFO *cs, bool cache_if_const):
+    Item_str_func(thd, a)
+  {
+    collation.set(cs, DERIVATION_IMPLICIT);
+    if (cache_if_const && args[0]->const_item() && !args[0]->is_expensive())
+    {
+      uint errors= 0;
+      String tmp, *str= args[0]->val_str(&tmp);
+      if (!str || str_value.copy(str->ptr(), str->length(),
+                                 str->charset(), cs, &errors))
+        null_value= 1;
+      use_cached_value= 1;
+      str_value.mark_as_const();
+      safe= (errors == 0);
+    }
+    else
+    {
+      use_cached_value= 0;
+      /*
+        Conversion from and to "binary" is safe.
+        Conversion to Unicode is safe.
+        Conversion from an expression with the ASCII repertoire
+        to any character set that can store characters U+0000..U+007F
+        is safe:
+        - All supported multibyte character sets can store U+0000..U+007F
+        - All supported 7bit character sets can store U+0000..U+007F
+          except those marked with MY_CS_NONASCII (e.g. swe7).
+        Other kind of conversions are potentially lossy.
+      */
+      safe= (args[0]->collation.collation == &my_charset_bin ||
+             cs == &my_charset_bin ||
+             (cs->state & MY_CS_UNICODE) ||
+             (args[0]->collation.repertoire == MY_REPERTOIRE_ASCII &&
+              (cs->mbmaxlen > 1 || !(cs->state & MY_CS_NONASCII))));
+    }
+  }
+  bool is_json_type() { return args[0]->is_json_type(); }
+  String *val_str(String *);
+  longlong val_int()
+  {
+    if (args[0]->result_type() == STRING_RESULT)
+      return Item_str_func::val_int();
+    longlong res= args[0]->val_int();
+    if ((null_value= args[0]->null_value))
+      return 0;
+    return res;
+  }
+  double val_real()
+  {
+    if (args[0]->result_type() == STRING_RESULT)
+      return Item_str_func::val_real();
+    double res= args[0]->val_real();
+    if ((null_value= args[0]->null_value))
+      return 0;
+    return res;
+  }
+  my_decimal *val_decimal(my_decimal *d)
+  {
+    if (args[0]->result_type() == STRING_RESULT)
+      return Item_str_func::val_decimal(d);
+    my_decimal *res= args[0]->val_decimal(d);
+    if ((null_value= args[0]->null_value))
+      return NULL;
+    return res;
+  }
+  bool get_date(THD *thd, MYSQL_TIME *ltime, date_mode_t fuzzydate)
+  {
+    if (args[0]->result_type() == STRING_RESULT)
+      return Item_str_func::get_date(thd, ltime, fuzzydate);
+    bool res= args[0]->get_date(thd, ltime, fuzzydate);
+    if ((null_value= args[0]->null_value))
+      return 1;
+    return res;
+  }
+  bool fix_length_and_dec();
+  const char *func_name() const { return "convert"; }
+  void print(String *str, enum_query_type query_type);
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_conv_charset>(thd, this); }
+};
+
+class Item_func_set_collation :public Item_str_func
+{
+  CHARSET_INFO *m_set_collation;
+public:
+  Item_func_set_collation(THD *thd, Item *a, CHARSET_INFO *set_collation):
+    Item_str_func(thd, a), m_set_collation(set_collation) {}
+  String *val_str(String *);
+  bool fix_length_and_dec();
+  bool eq(const Item *item, bool binary_cmp) const;
+  const char *func_name() const { return "collate"; }
+  enum precedence precedence() const { return COLLATE_PRECEDENCE; }
+  enum Functype functype() const { return COLLATE_FUNC; }
+  void print(String *str, enum_query_type query_type);
+  Item_field *field_for_view_update()
+  {
+    /* this function is transparent for view updating */
+    return args[0]->field_for_view_update();
+  }
+  bool need_parentheses_in_default() { return true; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_set_collation>(thd, this); }
+};
+
+
+class Item_func_expr_str_metadata :public Item_str_func
+{
+public:
+  Item_func_expr_str_metadata(THD *thd, Item *a): Item_str_func(thd, a) { }
+  bool fix_length_and_dec()
+  {
+     collation.set(system_charset_info);
+     max_length= 64 * collation.collation->mbmaxlen; // should be enough
+     maybe_null= 0;
+     return FALSE;
+  };
+  table_map not_null_tables() const { return 0; }
+  Item* propagate_equal_fields(THD *thd, const Context &ctx, COND_EQUAL *cond)
+  { return this; }
+  bool const_item() const { return true; }
+};
+
+
+class Item_func_charset :public Item_func_expr_str_metadata
+{
+public:
+  Item_func_charset(THD *thd, Item *a)
+    :Item_func_expr_str_metadata(thd, a) { }
+  String *val_str(String *);
+  const char *func_name() const { return "charset"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_charset>(thd, this); }
+};
+
+
+class Item_func_collation :public Item_func_expr_str_metadata
+{
+public:
+  Item_func_collation(THD *thd, Item *a)
+    :Item_func_expr_str_metadata(thd, a) {}
+  String *val_str(String *);
+  const char *func_name() const { return "collation"; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_collation>(thd, this); }
+};
+
+
+class Item_func_weight_string :public Item_str_func
+{
+  String tmp_value;
+  uint flags;
+  uint nweights;
+  uint result_length;
+public:
+  Item_func_weight_string(THD *thd, Item *a, uint result_length_arg,
+                          uint nweights_arg, uint flags_arg):
+    Item_str_func(thd, a)
+  {
+    nweights= nweights_arg;
+    flags= flags_arg;
+    result_length= result_length_arg;
+  }
+  const char *func_name() const { return "weight_string"; }
+  String *val_str(String *);
+  bool fix_length_and_dec();
+  bool eq(const Item *item, bool binary_cmp) const
+  {
+    if (!Item_str_func::eq(item, binary_cmp))
+      return false;
+    Item_func_weight_string *that= (Item_func_weight_string *)item;
+    return this->flags == that->flags &&
+           this->nweights == that->nweights &&
+           this->result_length == that->result_length;
+  }
+  Item* propagate_equal_fields(THD *thd, const Context &ctx, COND_EQUAL *cond)
+  { return this; }
+  void print(String *str, enum_query_type query_type);
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_weight_string>(thd, this); }
+};
+
+class Item_func_crc32 :public Item_long_func
+{
+  bool check_arguments() const
+  { return args[0]->check_type_can_return_str(func_name()); }
+  String value;
+public:
+  Item_func_crc32(THD *thd, Item *a): Item_long_func(thd, a)
+  { unsigned_flag= 1; }
+  const char *func_name() const { return "crc32"; }
+  bool fix_length_and_dec() { max_length=10; return FALSE; }
+  longlong val_int();
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_crc32>(thd, this); }
+};
+
+class Item_func_uncompressed_length : public Item_long_func_length
+{
+  String value;
+public:
+  Item_func_uncompressed_length(THD *thd, Item *a)
+   :Item_long_func_length(thd, a) {}
+  const char *func_name() const{return "uncompressed_length";}
+  bool fix_length_and_dec() { max_length=10; maybe_null= true; return FALSE; }
+  longlong val_int();
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_uncompressed_length>(thd, this); }
+};
+
+#ifdef HAVE_COMPRESS
+#define ZLIB_DEPENDED_FUNCTION ;
+#else
+#define ZLIB_DEPENDED_FUNCTION { null_value=1; return 0; }
+#endif
+
+class Item_func_compress: public Item_str_binary_checksum_func
+{
+  String tmp_value;
+public:
+  Item_func_compress(THD *thd, Item *a)
+   :Item_str_binary_checksum_func(thd, a) {}
+  bool fix_length_and_dec()
+  {
+    max_length= (args[0]->max_length * 120) / 100 + 12;
+    return FALSE;
+  }
+  const char *func_name() const{return "compress";}
+  String *val_str(String *) ZLIB_DEPENDED_FUNCTION
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_compress>(thd, this); }
+};
+
+class Item_func_uncompress: public Item_str_binary_checksum_func
+{
+  String tmp_value;
+public:
+  Item_func_uncompress(THD *thd, Item *a)
+   :Item_str_binary_checksum_func(thd, a) {}
+  bool fix_length_and_dec()
+  {
+    maybe_null= 1; max_length= MAX_BLOB_WIDTH;
+    return FALSE;
+  }
+  const char *func_name() const{return "uncompress";}
+  String *val_str(String *) ZLIB_DEPENDED_FUNCTION
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_uncompress>(thd, this); }
+};
+
+
+class Item_func_uuid: public Item_str_func
+{
+public:
+  Item_func_uuid(THD *thd): Item_str_func(thd) {}
+  bool fix_length_and_dec()
+  {
+    collation.set(DTCollation_numeric());
+    fix_char_length(MY_UUID_STRING_LENGTH);
+    return FALSE;
+  }
+  bool const_item() const { return false; }
+  table_map used_tables() const { return RAND_TABLE_BIT; }
+  const char *func_name() const{ return "uuid"; }
+  String *val_str(String *);
+  bool check_vcol_func_processor(void *arg)
+  {
+    return mark_unsupported_function(func_name(), "()", arg, VCOL_NON_DETERMINISTIC);
+  }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_uuid>(thd, this); }
+};
+
+
+class Item_func_dyncol_create: public Item_str_func
+{
+protected:
+  DYNCALL_CREATE_DEF *defs;
+  DYNAMIC_COLUMN_VALUE *vals;
+  uint *keys_num;
+  LEX_STRING *keys_str;
+  bool names, force_names;
+  bool prepare_arguments(THD *thd, bool force_names);
+  void print_arguments(String *str, enum_query_type query_type);
+public:
+  Item_func_dyncol_create(THD *thd, List<Item> &args, DYNCALL_CREATE_DEF *dfs);
+  bool fix_fields(THD *thd, Item **ref);
+  bool fix_length_and_dec();
+  const char *func_name() const{ return "column_create"; }
+  String *val_str(String *);
+  void print(String *str, enum_query_type query_type);
+  enum Functype functype() const   { return DYNCOL_FUNC; }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_dyncol_create>(thd, this); }
+};
+
+
+class Item_func_dyncol_add: public Item_func_dyncol_create
+{
+public:
+  Item_func_dyncol_add(THD *thd, List<Item> &args_arg, DYNCALL_CREATE_DEF *dfs):
+    Item_func_dyncol_create(thd, args_arg, dfs)
+  {}
+  const char *func_name() const{ return "column_add"; }
+  String *val_str(String *);
+  void print(String *str, enum_query_type query_type);
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_dyncol_add>(thd, this); }
+};
+
+class Item_func_dyncol_json: public Item_str_func
+{
+public:
+  Item_func_dyncol_json(THD *thd, Item *str): Item_str_func(thd, str)
+    {collation.set(DYNCOL_UTF);}
+  const char *func_name() const{ return "column_json"; }
+  String *val_str(String *);
+  bool fix_length_and_dec()
+  {
+    max_length= MAX_BLOB_WIDTH;
+    maybe_null= 1;
+    decimals= 0;
+    return FALSE;
+  }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_dyncol_json>(thd, this); }
+};
+
+/*
+  The following functions is always called from an Item_cast function
+*/
+
+class Item_dyncol_get: public Item_str_func
+{
+public:
+  Item_dyncol_get(THD *thd, Item *str, Item *num): Item_str_func(thd, str, num)
+  {}
+  bool fix_length_and_dec()
+  { maybe_null= 1;; max_length= MAX_BLOB_WIDTH; return FALSE; }
+  /* Mark that collation can change between calls */
+  bool dynamic_result() { return 1; }
+
+  const char *func_name() const { return "column_get"; }
+  String *val_str(String *);
+  longlong val_int();
+  longlong val_int_signed_typecast()
+  {
+    unsigned_flag= false;   // Mark that we want to have a signed value
+    longlong value= val_int(); // val_int() can change unsigned_flag
+    if (!null_value && unsigned_flag && value < 0)
+      push_note_converted_to_negative_complement(current_thd);
+    return value;
+  }
+  longlong val_int_unsigned_typecast()
+  {
+    unsigned_flag= true; // Mark that we want to have an unsigned value
+    longlong value= val_int(); // val_int() can change unsigned_flag
+    if (!null_value && unsigned_flag == 0 && value < 0)
+      push_note_converted_to_positive_complement(current_thd);
+    return value;
+  }
+  double val_real();
+  my_decimal *val_decimal(my_decimal *);
+  bool get_dyn_value(THD *thd, DYNAMIC_COLUMN_VALUE *val, String *tmp);
+  bool get_date(THD *thd, MYSQL_TIME *ltime, date_mode_t fuzzydate);
+  void print(String *str, enum_query_type query_type);
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_dyncol_get>(thd, this); }
+};
+
+
+class Item_func_dyncol_list: public Item_str_func
+{
+public:
+  Item_func_dyncol_list(THD *thd, Item *str): Item_str_func(thd, str)
+    {collation.set(DYNCOL_UTF);}
+  bool fix_length_and_dec()
+  { maybe_null= 1; max_length= MAX_BLOB_WIDTH; return FALSE; };
+  const char *func_name() const{ return "column_list"; }
+  String *val_str(String *);
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_dyncol_list>(thd, this); }
+};
+
+/*
+  this is used by JOIN_TAB::keep_current_rowid
+  and stores handler::position().
+  It has nothing to do with _rowid pseudo-column, that the parser supports.
+*/
+class Item_temptable_rowid :public Item_str_func
+{
+public:
+  TABLE *table;
+  Item_temptable_rowid(TABLE *table_arg);
+  const Type_handler *type_handler() const { return &type_handler_string; }
+  Field *create_tmp_field(MEM_ROOT *root, bool group, TABLE *table)
+  { return create_table_field_from_handler(root, table); }
+  String *val_str(String *str);
+  enum Functype functype() const { return  TEMPTABLE_ROWID; }
+  const char *func_name() const { return "<rowid>"; }
+  bool fix_length_and_dec();
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_temptable_rowid>(thd, this); }
+};
+#ifdef WITH_WSREP
+
+#include "wsrep_api.h"
+
+class Item_func_wsrep_last_written_gtid: public Item_str_ascii_func
+{
+  String gtid_str;
+public:
+  Item_func_wsrep_last_written_gtid(THD *thd): Item_str_ascii_func(thd) {}
+  const char *func_name() const { return "wsrep_last_written_gtid"; }
+  String *val_str_ascii(String *);
+  bool fix_length_and_dec()
+  {
+    max_length= WSREP_GTID_STR_LEN;
+    maybe_null= true;
+    return FALSE;
+  }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_wsrep_last_written_gtid>(thd, this); }
+};
+
+class Item_func_wsrep_last_seen_gtid: public Item_str_ascii_func
+{
+  String gtid_str;
+public:
+  Item_func_wsrep_last_seen_gtid(THD *thd): Item_str_ascii_func(thd) {}
+  const char *func_name() const { return "wsrep_last_seen_gtid"; }
+  String *val_str_ascii(String *);
+  bool fix_length_and_dec()
+  {
+    max_length= WSREP_GTID_STR_LEN;
+    maybe_null= true;
+    return FALSE;
+  }
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_wsrep_last_seen_gtid>(thd, this); }
+};
+
+class Item_func_wsrep_sync_wait_upto: public Item_int_func
+{
+  String value;
+public:
+ Item_func_wsrep_sync_wait_upto(THD *thd, Item *a): Item_int_func(thd, a) {}
+ Item_func_wsrep_sync_wait_upto(THD *thd, Item *a, Item* b): Item_int_func(thd, a, b) {}
+  const Type_handler *type_handler() const { return &type_handler_string; }
+  const char *func_name() const { return "wsrep_sync_wait_upto_gtid"; }
+  longlong val_int();
+  Item *get_copy(THD *thd)
+  { return get_item_copy<Item_func_wsrep_sync_wait_upto>(thd, this); }
+};
+#endif /* WITH_WSREP */
+
+#endif /* ITEM_STRFUNC_INCLUDED */