/*
Copyright (c) 2018, 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 02110-1301 USA */
#ifndef LEX_STRING_INCLUDED
#define LEX_STRING_INCLUDED
typedef struct st_mysql_const_lex_string LEX_CSTRING;
class Lex_cstring : public LEX_CSTRING
{
public:
Lex_cstring()
{
str= NULL;
length= 0;
}
Lex_cstring(const LEX_CSTRING &str)
{
LEX_CSTRING::operator=(str);
}
Lex_cstring(const char *_str, size_t _len)
{
str= _str;
length= _len;
}
Lex_cstring(const char *start, const char *end)
{
DBUG_ASSERT(start <= end);
str= start;
length= end - start;
}
void set(const char *_str, size_t _len)
{
str= _str;
length= _len;
}
/*
Trim left white spaces.
Assumes that there are no multi-bytes characters
that can be considered white-space.
*/
Lex_cstring ltrim_whitespace(CHARSET_INFO *cs) const
{
DBUG_ASSERT(cs->mbminlen == 1);
Lex_cstring str= *this;
while (str.length > 0 && my_isspace(cs, str.str[0]))
{
str.length--;
str.str++;
}
return str;
}
/*
Trim right white spaces.
Assumes that there are no multi-bytes characters
that can be considered white-space.
Also, assumes that the character set supports backward space parsing.
*/
Lex_cstring rtrim_whitespace(CHARSET_INFO *cs) const
{
DBUG_ASSERT(cs->mbminlen == 1);
Lex_cstring str= *this;
while (str.length > 0 && my_isspace(cs, str.str[str.length - 1]))
{
str.length --;
}
return str;
}
/*
Trim all spaces.
*/
Lex_cstring trim_whitespace(CHARSET_INFO *cs) const
{
return ltrim_whitespace(cs).rtrim_whitespace(cs);
}
/*
Trim all spaces and return the length of the leading space sequence.
*/
Lex_cstring trim_whitespace(CHARSET_INFO *cs, size_t *prefix_length) const
{
Lex_cstring tmp= Lex_cstring(*this).ltrim_whitespace(cs);
if (prefix_length)
*prefix_length= tmp.str - str;
return tmp.rtrim_whitespace(cs);
}
/*
Return the "n" leftmost bytes if this[0] is longer than "n" bytes,
or return this[0] itself otherwise.
*/
Lex_cstring left(size_t n) const
{
return Lex_cstring(str, MY_MIN(length, n));
}
/*
If this[0] is shorter than "pos" bytes, then return an empty string.
Otherwise, return a substring of this[0] starting from
the byte position "pos" until the end.
*/
Lex_cstring substr(size_t pos) const
{
return length <= pos ? Lex_cstring(str + length, (size_t) 0) :
Lex_cstring(str + pos, length - pos);
}
// Check if a prefix of this[0] is equal to "rhs".
bool starts_with(const LEX_CSTRING &rhs) const
{
DBUG_ASSERT(str);
DBUG_ASSERT(rhs.str);
return length >= rhs.length && !memcmp(str, rhs.str, rhs.length);
}
};
class Lex_cstring_strlen: public Lex_cstring
{
public:
explicit Lex_cstring_strlen(const char *from)
:Lex_cstring(from, from ? strlen(from) : 0)
{ }
};
/* Functions to compare if two lex strings are equal */
static inline bool lex_string_cmp(CHARSET_INFO *charset, const LEX_CSTRING *a,
const LEX_CSTRING *b)
{
return my_strcasecmp(charset, a->str, b->str);
}
/*
Compare to LEX_CSTRING's and return 0 if equal
*/
static inline bool cmp(const LEX_CSTRING *a, const LEX_CSTRING *b)
{
return a->length != b->length ||
(a->length && memcmp(a->str, b->str, a->length));
}
static inline bool cmp(const LEX_CSTRING a, const LEX_CSTRING b)
{
return a.length != b.length || (a.length && memcmp(a.str, b.str, a.length));
}
/*
Compare if two LEX_CSTRING are equal. Assumption is that
character set is ASCII (like for plugin names)
*/
static inline bool lex_string_eq(const LEX_CSTRING *a, const LEX_CSTRING *b)
{
if (a->length != b->length)
return 0; /* Different */
return strcasecmp(a->str, b->str) == 0;
}
/*
To be used when calling lex_string_eq with STRING_WITH_LEN() as second
argument
*/
static inline bool lex_string_eq(const LEX_CSTRING *a, const char *b, size_t b_length)
{
if (a->length != b_length)
return 0; /* Different */
return strcasecmp(a->str, b) == 0;
}
#endif /* LEX_STRING_INCLUDED */
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