1 files changed, 107 insertions, 0 deletions
diff --git a/sql/charset_collations.cc b/sql/charset_collations.cc
new file mode 100644
index 00000000000..c2c2cc2e7d6
--- /dev/null
+++ b/sql/charset_collations.cc
@@ -0,0 +1,107 @@
+/* Copyright (c) 2023, MariaDB Corporation.
+
+   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 "my_global.h"
+#include "my_sys.h"
+#include "lex_charset.h"
+#include "mysqld_error.h"
+#include "charset_collations.h"
+#include "simple_tokenizer.h"
+
+bool Charset_collation_map_st::insert_or_replace(
+                                  const Lex_exact_charset &charset,
+                                  const Lex_extended_collation &collation,
+                                  bool error_on_conflicting_duplicate)
+{
+  Lex_exact_charset_opt_extended_collate res(charset);
+  Used used;
+  if (res.merge_collation_override(&used, *this, collation))
+    return true;
+
+  if (error_on_conflicting_duplicate)
+  {
+    const Elem_st *dup;
+    if ((dup= find_elem_by_charset_id(charset.charset_info()->number)) &&
+        dup->collation() != res.collation().charset_info())
+    {
+      my_error(ER_CONFLICTING_DECLARATIONS, MYF(0),
+               "", dup->collation()->coll_name.str,
+               "", res.collation().charset_info()->coll_name.str);
+      return true;
+    }
+  }
+  return insert_or_replace(Elem(charset.charset_info(),
+                                res.collation().charset_info()));
+}
+
+
+bool Charset_collation_map_st::from_text(const LEX_CSTRING &str, myf utf8_flag)
+{
+  init();
+  Simple_tokenizer stream(str.str, str.length);
+
+  stream.get_spaces();
+  if (stream.eof())
+    return 0; /* Empty string */
+
+  for ( ; ; )
+  {
+    LEX_CSTRING charset_name= stream.get_ident();
+    if (!charset_name.length)
+      return true;
+    stream.get_spaces();
+    if (stream.get_char('='))
+      return true;
+    stream.get_spaces();
+    LEX_CSTRING collation_name= stream.get_ident();
+    if (!collation_name.length)
+      return true;
+
+    char charset_name_c[MY_CS_CHARACTER_SET_NAME_SIZE + 1/*for '\0'*/];
+    strmake(charset_name_c, charset_name.str, charset_name.length);
+    CHARSET_INFO *cs= get_charset_by_csname(charset_name_c,
+                                            MY_CS_PRIMARY, utf8_flag);
+    if (!cs)
+    {
+      my_error(ER_UNKNOWN_CHARACTER_SET, MYF(0), charset_name_c);
+      return true;
+    }
+
+    char collation_name_c[MY_CS_COLLATION_NAME_SIZE + 1/*for '\0'*/];
+    strmake(collation_name_c, collation_name.str, collation_name.length);
+
+    Lex_exact_collation tmpec(&my_charset_bin);
+    Lex_extended_collation tmp(tmpec);
+    if (tmp.set_by_name(collation_name_c, utf8_flag))
+      return true;
+
+    /*
+      Don't allow duplicate conflicting declarations within the same string:
+        SET @@var='utf8mb3=utf8mb3_general_ci,utf8mb3=utf8mb3_bin';
+    */
+    if (insert_or_replace(Lex_exact_charset(cs), tmp, true/*err on dup*/))
+      return true;
+
+    stream.get_spaces();
+    if (stream.eof())
+      break;
+    if (stream.ptr()[0] != ',')
+      return true;
+    stream.get_char(',');
+    stream.get_spaces();
+  }
+  return false;
+}