System Versioning pre0.12

Merge remote-tracking branch 'origin/archive/2017-10-17' into 10.3

sql/vers_string.h

@@ -0,0 +1,133 @@
+#ifndef VERS_STRING_INCLUDED
+#define VERS_STRING_INCLUDED
+
+struct Compare_strncmp
+{
+  int operator()(const LEX_CSTRING& a, const LEX_CSTRING& b) const
+  {
+    return strncmp(a.str, b.str, a.length);
+  }
+  static CHARSET_INFO* charset()
+  {
+    return system_charset_info;
+  }
+};
+
+template <CHARSET_INFO* &CS= system_charset_info>
+struct Compare_my_strcasecmp
+{
+  int operator()(const LEX_CSTRING& a, const LEX_CSTRING& b) const
+  {
+    DBUG_ASSERT(a.str[a.length] == 0 && b.str[b.length] == 0);
+    return my_strcasecmp(CS, a.str, b.str);
+  }
+  static CHARSET_INFO* charset()
+  {
+    return CS;
+  }
+};
+
+typedef Compare_my_strcasecmp<files_charset_info> Compare_fs;
+typedef Compare_my_strcasecmp<table_alias_charset> Compare_t;
+
+template <class Storage= LEX_CSTRING>
+struct LEX_STRING_u : public Storage
+{
+  LEX_STRING_u()
+  {
+    Storage::str= NULL;
+    Storage::length= 0;
+  }
+  LEX_STRING_u(const char *_str, uint32 _len, CHARSET_INFO *)
+  {
+    Storage::str= _str;
+    Storage::length= _len;
+  }
+  uint32 length() const
+  {
+    return Storage::length;
+  }
+  const char *ptr() const
+  {
+    return Storage::str;
+  }
+  void set(const char *_str, uint32 _len, CHARSET_INFO *)
+  {
+    Storage::str= _str;
+    Storage::length= _len;
+  }
+  const LEX_CSTRING& lex_cstring() const
+  {
+    return *this;
+  }
+  const LEX_STRING& lex_string() const
+  {
+    return *(LEX_STRING *)this;
+  }
+};
+
+template <class Compare= Compare_strncmp, class Storage= LEX_STRING_u<> >
+struct XString : public Storage
+{
+public:
+  XString() {}
+  XString(const char *_str, size_t _len) :
+    Storage(_str, _len, Compare::charset())
+  {
+  }
+  XString(const LEX_STRING src) :
+    Storage(src.str, src.length, Compare::charset())
+  {
+  }
+  XString(const LEX_CSTRING src) :
+    Storage(src.str, src.length, Compare::charset())
+  {
+  }
+  XString(const char *_str) :
+    Storage(_str, strlen(_str), Compare::charset())
+  {
+  }
+  bool operator== (const XString& b) const
+  {
+    return Storage::length() == b.length() && 0 == Compare()(this->lex_cstring(), b.lex_cstring());
+  }
+  bool operator!= (const XString& b) const
+  {
+    return !(*this == b);
+  }
+  operator const char* () const
+  {
+    return Storage::ptr();
+  }
+  operator LEX_CSTRING& () const
+  {
+    return this->lex_cstring();
+  }
+  operator LEX_STRING () const
+  {
+    LEX_STRING res;
+    res.str= const_cast<char *>(this->ptr());
+    res.length= this->length();
+    return res;
+  }
+  operator bool () const
+  {
+    return Storage::ptr() != NULL;
+  }
+};
+
+typedef XString<> LString;
+typedef XString<Compare_fs> LString_fs;
+typedef XString<Compare_my_strcasecmp<> > LString_i;
+
+typedef XString<Compare_strncmp, String> SString;
+typedef XString<Compare_fs, String> SString_fs;
+typedef XString<Compare_t, String> SString_t;
+
+
+#define XSTRING_WITH_LEN(X) (X).ptr(), (X).length()
+#define DB_WITH_LEN(X) (X).db, (X).db_length
+#define TABLE_NAME_WITH_LEN(X) (X).table_name, (X).table_name_length
+
+
+#endif // VERS_STRING_INCLUDED