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merge with 5.3

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sql/sql_insert.cc:
  CREATE ... IF NOT EXISTS may do nothing, but
  it is still not a failure. don't forget to my_ok it.
  ******
  CREATE ... IF NOT EXISTS may do nothing, but
  it is still not a failure. don't forget to my_ok it.
sql/sql_table.cc:
  small cleanup
  ******
  small cleanup
This commit is contained in:
Sergei Golubchik
2011-10-19 21:45:18 +02:00
parent 4e46d8e5bf 5dc1a2231f
commit 76f0b94bb0
1705 changed files with 166414 additions and 39720 deletions
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75
include/m_string.h
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@@ -90,6 +90,12 @@ extern const char _dig_vec_lower[];
extern char *strmov_overlapp(char *dest, const char *src);
#if defined(_lint) || defined(FORCE_INIT_OF_VARS)
#define LINT_INIT_STRUCT(var) bzero(&var, sizeof(var)) /* No uninitialize-warning */
#else
#define LINT_INIT_STRUCT(var)
#endif
/* Prototypes for string functions */
extern void bmove_upp(uchar *dst,const uchar *src,size_t len);
@@ -215,75 +221,6 @@ struct st_mysql_const_unsigned_lex_string
};
typedef struct st_mysql_const_unsigned_lex_string LEX_CUSTRING;
/* SPACE_INT is a word that contains only spaces */
#if SIZEOF_INT == 4
#define SPACE_INT 0x20202020
#elif SIZEOF_INT == 8
#define SPACE_INT 0x2020202020202020
#else
#error define the appropriate constant for a word full of spaces
#endif
/**
Skip trailing space.
On most systems reading memory in larger chunks (ideally equal to the size of
the chinks that the machine physically reads from memory) causes fewer memory
access loops and hence increased performance.
This is why the 'int' type is used : it's closest to that (according to how
it's defined in C).
So when we determine the amount of whitespace at the end of a string we do
the following :
1. We divide the string into 3 zones :
a) from the start of the string (__start) to the first multiple
of sizeof(int) (__start_words)
b) from the end of the string (__end) to the last multiple of sizeof(int)
(__end_words)
c) a zone that is aligned to sizeof(int) and can be safely accessed
through an int *
2. We start comparing backwards from (c) char-by-char. If all we find is
space then we continue
3. If there are elements in zone (b) we compare them as unsigned ints to a
int mask (SPACE_INT) consisting of all spaces
4. Finally we compare the remaining part (a) of the string char by char.
This covers for the last non-space unsigned int from 3. (if any)
This algorithm works well for relatively larger strings, but it will slow
the things down for smaller strings (because of the additional calculations
and checks compared to the naive method). Thus the barrier of length 20
is added.
@param ptr pointer to the input string
@param len the length of the string
@return the last non-space character
*/
static inline const uchar *skip_trailing_space(const uchar *ptr,size_t len)
{
const uchar *end= ptr + len;
if (len > 20)
{
const uchar *end_words= (const uchar *)(intptr)
(((ulonglong)(intptr)end) / SIZEOF_INT * SIZEOF_INT);
const uchar *start_words= (const uchar *)(intptr)
((((ulonglong)(intptr)ptr) + SIZEOF_INT - 1) / SIZEOF_INT * SIZEOF_INT);
DBUG_ASSERT(((ulonglong)(intptr)ptr) >= SIZEOF_INT);
if (end_words > ptr)
{
while (end > end_words && end[-1] == 0x20)
end--;
if (end[-1] == 0x20 && start_words < end_words)
while (end > start_words && ((unsigned *)end)[-1] == SPACE_INT)
end -= SIZEOF_INT;
}
}
while (end > ptr && end[-1] == 0x20)
end--;
return (end);
}
static inline void lex_string_set(LEX_STRING *lex_str, const char *c_str)
{
lex_str->str= (char *) c_str;