Bug#31081 server crash in regexp function

Problem: The "regex" library written by Henry Spencer
does not support tricky character sets like UCS2.
Fix: convert tricky character sets to UTF8 before calling
regex functions.


mysql-test/r/ctype_uca.result:
  Adding tests
mysql-test/r/ctype_ucs.result:
  Adding tests
mysql-test/r/ctype_utf8.result:
  Adding tests
mysql-test/r/func_regexp.result:
  Adding tests
mysql-test/t/ctype_uca.test:
  Adding tests
mysql-test/t/ctype_ucs.test:
  Adding tests
mysql-test/t/ctype_utf8.test:
  Adding tests
mysql-test/t/func_regexp.test:
  Adding tests
sql/item_cmpfunc.cc:
  - Adding new method Item_func_regex::regcomp()
  to share more code between fix_fields() and val_int()
  - Adding conversion from ASCII-incompatible charsets like UCS2
  to UTF8, because the "regexp" does not support these charsets
  - Additional optimization: calculate flags for regcomp only
    once in fix_fields, instead of every regcomp()
sql/item_cmpfunc.h:
  Adding prototypes for new members and methods
mysql-test/include/ctype_regex.inc:
  New BitKeeper file ``mysql-test/include/ctype_regex.inc''
  
  Moving common regular expression tests into a separate
  file and uncluding it into func_regexp and into many ctype_xxx tests.

1 files changed, 4 insertions, 0 deletions

diff --git a/sql/item_cmpfunc.h b/sql/item_cmpfunc.h
index 8410c66b034..11851e9a4e4 100644
--- a/sql/item_cmpfunc.h
+++ b/sql/item_cmpfunc.h
@@ -1313,6 +1313,10 @@ class Item_func_regex :public Item_bool_func
   bool regex_is_const;
   String prev_regexp;
   DTCollation cmp_collation;
+  CHARSET_INFO *regex_lib_charset;
+  int regex_lib_flags;
+  String conv;
+  bool regcomp(bool send_error);
 public:
   Item_func_regex(Item *a,Item *b) :Item_bool_func(a,b),
     regex_compiled(0),regex_is_const(0) {}