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MySQL 5.1: Item_func_trim Class Reference

Item_func_trim Class Reference

#include <item_strfunc.h>

Inheritance diagram for Item_func_trim:

[legend]Collaboration diagram for Item_func_trim:

[legend]List of all members.


Public Member Functions
	Item_func_trim (Item a, Item b)
	Item_func_trim (Item *a)
String *	val_str (String *)
void	fix_length_and_dec ()
const char *	func_name () const
void	print (String *str)
virtual const char *	mode_name () const
bool	check_partition_func_processor (byte *bool_arg)
Protected Attributes
String	tmp_value
String	remove

Detailed Description

Definition at line 232 of file item_strfunc.h.

Constructor & Destructor Documentation

Item_func_trim::Item_func_trim	(	Item *	a,
		Item *	b
	)			`[inline]`

Definition at line 238 of file item_strfunc.h.

00238 :Item_str_func(a,b) {}

Item_func_trim::Item_func_trim ( Item * a ) [inline]

Definition at line 239 of file item_strfunc.h.

00239 :Item_str_func(a) {}

Member Function Documentation

bool Item_func_trim::check_partition_func_processor ( byte * bool_arg ) [inline, virtual]

Reimplemented from Item.

Definition at line 245 of file item_strfunc.h.

00245 { return 0;}

void Item_func_trim::fix_length_and_dec ( ) [virtual]

Implements Item_result_field.

Definition at line 1488 of file item_strfunc.cc.

References Item_func::agg_arg_charsets(), Item_func::arg_count, Item_func::args, DTCollation::collation, Item::collation, Item::max_length, MY_COLL_CMP_CONV, remove, DTCollation::set(), String::set_ascii(), and String::set_charset().

01489 {
01490   max_length= args[0]->max_length;
01491   if (arg_count == 1)
01492   {
01493     collation.set(args[0]->collation);
01494     remove.set_charset(collation.collation);
01495     remove.set_ascii(" ",1);
01496   }
01497   else
01498   {
01499     // Handle character set for args[1] and args[0].
01500     // Note that we pass args[1] as the first item, and args[0] as the second.
01501     if (agg_arg_charsets(collation, &args[1], 2, MY_COLL_CMP_CONV, -1))
01502       return;
01503   }
01504 }

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const char* Item_func_trim::func_name ( ) const [inline, virtual]

Implements Item_func.

Reimplemented in Item_func_ltrim, and Item_func_rtrim.

Definition at line 242 of file item_strfunc.h.

Referenced by print().

00242 { return "trim"; }

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virtual const char* Item_func_trim::mode_name ( ) const [inline, virtual]

Reimplemented in Item_func_ltrim, and Item_func_rtrim.

Definition at line 244 of file item_strfunc.h.

Referenced by print().

00244 { return "both"; }

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void Item_func_trim::print ( String * str ) [virtual]

Reimplemented from Item_func.

Definition at line 1506 of file item_strfunc.cc.

References String::append(), Item_func::arg_count, Item_func::args, func_name(), mode_name(), Item::print(), Item_func::print(), and STRING_WITH_LEN.

01507 {
01508   if (arg_count == 1)
01509   {
01510     Item_func::print(str);
01511     return;
01512   }
01513   str->append(Item_func_trim::func_name());
01514   str->append('(');
01515   str->append(mode_name());
01516   str->append(' ');
01517   args[1]->print(str);
01518   str->append(STRING_WITH_LEN(" from "));
01519   args[0]->print(str);
01520   str->append(')');
01521 }

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String * Item_func_trim::val_str ( String * ) [virtual]

Implements Item.

Reimplemented in Item_func_ltrim, and Item_func_rtrim.

Definition at line 1426 of file item_strfunc.cc.

References Item_func::arg_count, Item_func::args, String::charset(), DBUG_ASSERT, Item::fixed, String::length(), LINT_INIT, MAX_FIELD_WIDTH, memcmp(), my_ismbchar, Item::null_value, p, String::ptr(), remove, String::set(), system_charset_info, tmp_value, use_mb, and Item::val_str().

01427 {
01428   DBUG_ASSERT(fixed == 1);
01429   char buff[MAX_FIELD_WIDTH], *ptr, *end;
01430   const char *r_ptr;
01431   String tmp(buff, sizeof(buff), system_charset_info);
01432   String *res, *remove_str;
01433   uint remove_length;
01434   LINT_INIT(remove_length);
01435 
01436   res= args[0]->val_str(str);
01437   if ((null_value=args[0]->null_value))
01438     return 0;
01439   remove_str= &remove;                          /* Default value. */
01440   if (arg_count == 2)
01441   {
01442     remove_str= args[1]->val_str(&tmp);
01443     if ((null_value= args[1]->null_value))
01444       return 0;
01445   }
01446 
01447   if ((remove_length= remove_str->length()) == 0 ||
01448       remove_length > res->length())
01449     return res;
01450 
01451   ptr= (char*) res->ptr();
01452   end= ptr+res->length();
01453   r_ptr= remove_str->ptr();
01454   while (ptr+remove_length <= end && !memcmp(ptr,r_ptr,remove_length))
01455     ptr+=remove_length;
01456 #ifdef USE_MB
01457   if (use_mb(res->charset()))
01458   {
01459     char *p=ptr;
01460     register uint32 l;
01461  loop:
01462     while (ptr + remove_length < end)
01463     {
01464       if ((l=my_ismbchar(res->charset(), ptr,end))) ptr+=l;
01465       else ++ptr;
01466     }
01467     if (ptr + remove_length == end && !memcmp(ptr,r_ptr,remove_length))
01468     {
01469       end-=remove_length;
01470       ptr=p;
01471       goto loop;
01472     }
01473     ptr=p;
01474   }
01475   else
01476 #endif /* USE_MB */
01477   {
01478     while (ptr + remove_length <= end &&
01479            !memcmp(end-remove_length,r_ptr,remove_length))
01480       end-=remove_length;
01481   }
01482   if (ptr == res->ptr() && end == ptr+res->length())
01483     return res;
01484   tmp_value.set(*res,(uint) (ptr - res->ptr()),(uint) (end-ptr));
01485   return &tmp_value;
01486 }