sql_string.cc 18.7 KB
Newer Older
monty@hundin.mysql.fi's avatar
monty@hundin.mysql.fi committed
1 2 3 4 5 6 7 8
/* Copyright (C) 2000 MySQL AB

   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; either version 2 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
bk@work.mysql.com's avatar
bk@work.mysql.com committed
9
   but WITHOUT ANY WARRANTY; without even the implied warranty of
monty@hundin.mysql.fi's avatar
monty@hundin.mysql.fi committed
10 11 12 13 14 15
   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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
bk@work.mysql.com's avatar
bk@work.mysql.com committed
16 17 18 19 20 21 22

/* This file is originally from the mysql distribution. Coded by monty */

#ifdef __GNUC__
#pragma implementation				// gcc: Class implementation
#endif

23
#include <my_global.h>
bk@work.mysql.com's avatar
bk@work.mysql.com committed
24 25 26 27 28 29 30
#include <my_sys.h>
#include <m_string.h>
#include <m_ctype.h>
#ifdef HAVE_FCONVERT
#include <floatingpoint.h>
#endif

31 32 33 34 35
/*
  The following extern declarations are ok as these are interface functions
  required by the string function
*/

bk@work.mysql.com's avatar
bk@work.mysql.com committed
36 37 38 39 40 41 42 43 44 45 46 47
extern gptr sql_alloc(unsigned size);
extern void sql_element_free(void *ptr);

#include "sql_string.h"

/*****************************************************************************
** String functions
*****************************************************************************/

bool String::real_alloc(uint32 arg_length)
{
  arg_length=ALIGN_SIZE(arg_length+1);
48
  str_length=0;
bk@work.mysql.com's avatar
bk@work.mysql.com committed
49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84
  if (Alloced_length < arg_length)
  {
    free();
    if (!(Ptr=(char*) my_malloc(arg_length,MYF(MY_WME))))
      return TRUE;
    Alloced_length=arg_length;
    alloced=1;
  }
  Ptr[0]=0;
  return FALSE;
}


/*
** Check that string is big enough. Set string[alloc_length] to 0
** (for C functions)
*/

bool String::realloc(uint32 alloc_length)
{
  uint32 len=ALIGN_SIZE(alloc_length+1);
  if (Alloced_length < len)
  {
    char *new_ptr;
    if (alloced)
    {
      if ((new_ptr= (char*) my_realloc(Ptr,len,MYF(MY_WME))))
      {
	Ptr=new_ptr;
	Alloced_length=len;
      }
      else
	return TRUE;				// Signal error
    }
    else if ((new_ptr= (char*) my_malloc(len,MYF(MY_WME))))
    {
85 86
      if (str_length)				// Avoid bugs in memcpy on AIX
	memcpy(new_ptr,Ptr,str_length);
bk@work.mysql.com's avatar
bk@work.mysql.com committed
87 88 89 90 91 92 93 94 95 96 97 98
      new_ptr[str_length]=0;
      Ptr=new_ptr;
      Alloced_length=len;
      alloced=1;
    }
    else
      return TRUE;			// Signal error
  }
  Ptr[alloc_length]=0;			// This make other funcs shorter
  return FALSE;
}

99
bool String::set(longlong num, CHARSET_INFO *cs)
bk@work.mysql.com's avatar
bk@work.mysql.com committed
100
{
101 102 103
  uint l=20*cs->mbmaxlen+1;

  if (alloc(l))
bk@work.mysql.com's avatar
bk@work.mysql.com committed
104
    return TRUE;
105
  str_length=(uint32) (cs->cset->longlong10_to_str)(cs,Ptr,l,-10,num);
106
  str_charset=cs;
bk@work.mysql.com's avatar
bk@work.mysql.com committed
107 108 109
  return FALSE;
}

110
bool String::set(ulonglong num, CHARSET_INFO *cs)
bk@work.mysql.com's avatar
bk@work.mysql.com committed
111
{
112 113 114
  uint l=20*cs->mbmaxlen+1;

  if (alloc(l))
bk@work.mysql.com's avatar
bk@work.mysql.com committed
115
    return TRUE;
116
  str_length=(uint32) (cs->cset->longlong10_to_str)(cs,Ptr,l,10,num);
117
  str_charset=cs;
bk@work.mysql.com's avatar
bk@work.mysql.com committed
118 119 120
  return FALSE;
}

121
bool String::set(double num,uint decimals, CHARSET_INFO *cs)
bk@work.mysql.com's avatar
bk@work.mysql.com committed
122 123
{
  char buff[331];
124 125

  str_charset=cs;
bk@work.mysql.com's avatar
bk@work.mysql.com committed
126 127
  if (decimals >= NOT_FIXED_DEC)
  {
128 129
    uint32 len= my_sprintf(buff,(buff, "%.14g",num));// Enough for a DATETIME
    return copy(buff, len, &my_charset_latin1, cs);
bk@work.mysql.com's avatar
bk@work.mysql.com committed
130 131 132 133 134 135
  }
#ifdef HAVE_FCONVERT
  int decpt,sign;
  char *pos,*to;

  VOID(fconvert(num,(int) decimals,&decpt,&sign,buff+1));
136
  if (!my_isdigit(&my_charset_latin1, buff[1]))
bk@work.mysql.com's avatar
bk@work.mysql.com committed
137 138 139 140 141 142 143
  {						// Nan or Inf
    pos=buff+1;
    if (sign)
    {
      buff[0]='-';
      pos=buff;
    }
144
    return copy(pos,(uint32) strlen(pos), &my_charset_latin1, cs);
bk@work.mysql.com's avatar
bk@work.mysql.com committed
145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187
  }
  if (alloc((uint32) ((uint32) decpt+3+decimals)))
    return TRUE;
  to=Ptr;
  if (sign)
    *to++='-';

  pos=buff+1;
  if (decpt < 0)
  {					/* value is < 0 */
    *to++='0';
    if (!decimals)
      goto end;
    *to++='.';
    if ((uint32) -decpt > decimals)
      decpt= - (int) decimals;
    decimals=(uint32) ((int) decimals+decpt);
    while (decpt++ < 0)
      *to++='0';
  }
  else if (decpt == 0)
  {
    *to++= '0';
    if (!decimals)
      goto end;
    *to++='.';
  }
  else
  {
    while (decpt-- > 0)
      *to++= *pos++;
    if (!decimals)
      goto end;
    *to++='.';
  }
  while (decimals--)
    *to++= *pos++;

end:
  *to=0;
  str_length=(uint32) (to-Ptr);
  return FALSE;
#else
188
#ifdef HAVE_SNPRINTF
monty@donna.mysql.com's avatar
monty@donna.mysql.com committed
189 190
  buff[sizeof(buff)-1]=0;			// Safety
  snprintf(buff,sizeof(buff)-1, "%.*f",(int) decimals,num);
bk@work.mysql.com's avatar
bk@work.mysql.com committed
191 192 193
#else
  sprintf(buff,"%.*f",(int) decimals,num);
#endif
194
  return copy(buff,(uint32) strlen(buff), &my_charset_latin1, cs);
bk@work.mysql.com's avatar
bk@work.mysql.com committed
195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215
#endif
}


bool String::copy()
{
  if (!alloced)
  {
    Alloced_length=0;				// Force realloc
    return realloc(str_length);
  }
  return FALSE;
}

bool String::copy(const String &str)
{
  if (alloc(str.str_length))
    return TRUE;
  str_length=str.str_length;
  bmove(Ptr,str.Ptr,str_length);		// May be overlapping
  Ptr[str_length]=0;
216
  str_charset=str.str_charset;
bk@work.mysql.com's avatar
bk@work.mysql.com committed
217 218 219
  return FALSE;
}

220
bool String::copy(const char *str,uint32 arg_length, CHARSET_INFO *cs)
bk@work.mysql.com's avatar
bk@work.mysql.com committed
221 222 223
{
  if (alloc(arg_length))
    return TRUE;
224 225
  if ((str_length=arg_length))
    memcpy(Ptr,str,arg_length);
bk@work.mysql.com's avatar
bk@work.mysql.com committed
226
  Ptr[arg_length]=0;
227
  str_charset=cs;
bk@work.mysql.com's avatar
bk@work.mysql.com committed
228 229 230
  return FALSE;
}

231 232

/*
233 234 235 236 237 238 239 240 241 242 243 244 245 246 247
  Checks that the source string can be just copied to the destination string
  without conversion.

  SYNPOSIS

  needs_conversion()
  arg_length		Length of string to copy.
  from_cs		Character set to copy from
  to_cs			Character set to copy to
  uint32 *offset	Returns number of unaligned characters.

  RETURN
   0  No conversion needed
   1  Either character set conversion or adding leading  zeros
      (e.g. for UCS-2) must be done
248
*/
249 250 251 252 253

bool String::needs_conversion(uint32 arg_length,
			      CHARSET_INFO *from_cs,
			      CHARSET_INFO *to_cs,
			      uint32 *offset)
254
{
255
  *offset= 0;
256 257 258
  if ((to_cs == &my_charset_bin) || 
      (to_cs == from_cs) ||
      my_charset_same(from_cs, to_cs) ||
259 260
      ((from_cs == &my_charset_bin) &&
       (!(*offset=(arg_length % to_cs->mbminlen)))))
261 262 263 264
    return FALSE;
  return TRUE;
}

265

266
/*
267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288
  Copy a multi-byte character sets with adding leading zeros.

  SYNOPSIS

  copy_aligned()
  str			String to copy
  arg_length		Length of string. This should NOT be dividable with
			cs->mbminlen.
  offset		arg_length % cs->mb_minlength
  cs			Character set for 'str'

  NOTES
    For real multi-byte, ascii incompatible charactser sets,
    like UCS-2, add leading zeros if we have an incomplete character.
    Thus, 
      SELECT _ucs2 0xAA 
    will automatically be converted into
      SELECT _ucs2 0x00AA

  RETURN
    0  ok
    1  error
289 290
*/

291
bool String::copy_aligned(const char *str,uint32 arg_length, uint32 offset,
292
			  CHARSET_INFO *cs)
293 294
{
  /* How many bytes are in incomplete character */
295 296
  offset= cs->mbmaxlen - offset; /* How many zeros we should prepend */
  DBUG_ASSERT(offset && offset != cs->mbmaxlen);
297

298
  uint32 aligned_length= arg_length + offset;
299 300 301 302
  if (alloc(aligned_length))
    return TRUE;
  
  /*
303 304 305
    Note, this is only safe for little-endian UCS-2.
    If we add big-endian UCS-2 sometimes, this code
    will be more complicated. But it's OK for now.
306
  */
307 308
  bzero((char*) Ptr, offset);
  memcpy(Ptr + offset, str, arg_length);
309
  Ptr[aligned_length]=0;
310 311 312
  /* str_length is always >= 0 as arg_length is != 0 */
  str_length= aligned_length;
  str_charset= cs;
313 314 315
  return FALSE;
}

316 317 318 319 320

bool String::set_or_copy_aligned(const char *str,uint32 arg_length,
				 CHARSET_INFO *cs)
{
  /* How many bytes are in incomplete character */
321
  uint32 offset= (arg_length % cs->mbminlen); 
322
  
323
  if (!offset) /* All characters are complete, just copy */
324 325 326 327
  {
    set(str, arg_length, cs);
    return FALSE;
  }
328
  return copy_aligned(str, arg_length, offset, cs);
329 330
}

331
	/* Copy with charset convertion */
332

333 334 335
bool String::copy(const char *str, uint32 arg_length,
		  CHARSET_INFO *from_cs, CHARSET_INFO *to_cs)
{
336 337
  uint32 offset;
  if (!needs_conversion(arg_length, from_cs, to_cs, &offset))
338
    return copy(str, arg_length, to_cs);
339 340
  if ((from_cs == &my_charset_bin) && offset)
    return copy_aligned(str, arg_length, offset, to_cs);
341
  
342
  uint32 new_length= to_cs->mbmaxlen*arg_length;
343 344
  if (alloc(new_length))
    return TRUE;
345 346 347 348 349
  str_length=copy_and_convert((char*) Ptr, new_length, to_cs,
			      str, arg_length, from_cs);
  str_charset=to_cs;
  return FALSE;
}
350

351 352 353

/*
  Set a string to the value of a latin1-string, keeping the original charset
354
  
355 356 357 358
  SYNOPSIS
    copy_or_set()
    str			String of a simple charset (latin1)
    arg_length		Length of string
359

360 361 362 363 364 365 366 367 368 369 370
  IMPLEMENTATION
    If string object is of a simple character set, set it to point to the
    given string.
    If not, make a copy and convert it to the new character set.

  RETURN
    0	ok
    1	Could not allocate result buffer

*/

371
bool String::set_ascii(const char *str, uint32 arg_length)
372
{
bar@mysql.com's avatar
bar@mysql.com committed
373
  if (str_charset->mbminlen == 1)
374 375 376
  {
    set(str, arg_length, str_charset);
    return 0;
377
  }
378
  return copy(str, arg_length, &my_charset_latin1, str_charset);
379 380
}

381

bk@work.mysql.com's avatar
bk@work.mysql.com committed
382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399
/* This is used by mysql.cc */

bool String::fill(uint32 max_length,char fill_char)
{
  if (str_length > max_length)
    Ptr[str_length=max_length]=0;
  else
  {
    if (realloc(max_length))
      return TRUE;
    bfill(Ptr+str_length,max_length-str_length,fill_char);
    str_length=max_length;
  }
  return FALSE;
}

void String::strip_sp()
{
400
   while (str_length && my_isspace(str_charset,Ptr[str_length-1]))
bk@work.mysql.com's avatar
bk@work.mysql.com committed
401 402 403 404 405
    str_length--;
}

bool String::append(const String &s)
{
406 407 408 409 410 411 412
  if (s.length())
  {
    if (realloc(str_length+s.length()))
      return TRUE;
    memcpy(Ptr+str_length,s.ptr(),s.length());
    str_length+=s.length();
  }
bk@work.mysql.com's avatar
bk@work.mysql.com committed
413 414 415
  return FALSE;
}

416 417

/*
418
  Append an ASCII string to the a string of the current character set
419 420
*/

bk@work.mysql.com's avatar
bk@work.mysql.com committed
421 422
bool String::append(const char *s,uint32 arg_length)
{
423 424 425 426 427 428 429
  if (!arg_length)
    return FALSE;

  /*
    For an ASCII incompatible string, e.g. UCS-2, we need to convert
  */
  if (str_charset->mbminlen > 1)
430 431 432 433 434
  {
    uint32 add_length=arg_length * str_charset->mbmaxlen;
    if (realloc(str_length+ add_length))
      return TRUE;
    str_length+= copy_and_convert(Ptr+str_length, add_length, str_charset,
435
				  s, arg_length, &my_charset_latin1);
436 437
    return FALSE;
  }
438 439 440 441

  /*
    For an ASCII compatinble string we can just append.
  */
bk@work.mysql.com's avatar
bk@work.mysql.com committed
442 443 444 445 446 447 448
  if (realloc(str_length+arg_length))
    return TRUE;
  memcpy(Ptr+str_length,s,arg_length);
  str_length+=arg_length;
  return FALSE;
}

449

450 451 452 453 454 455 456 457 458 459
/*
  Append a 0-terminated ASCII string
*/

bool String::append(const char *s)
{
  return append(s, strlen(s));
}


460 461 462 463 464 465 466
/*
  Append a string in the given charset to the string
  with character set recoding
*/

bool String::append(const char *s,uint32 arg_length, CHARSET_INFO *cs)
{
467
  uint32 dummy_offset;
468
  
469
  if (needs_conversion(arg_length, cs, str_charset, &dummy_offset))
470
  {
471 472 473
    uint32 add_length= arg_length / cs->mbminlen * str_charset->mbmaxlen;
    if (realloc(str_length + add_length)) 
      return TRUE;
474 475 476
    str_length+= copy_and_convert(Ptr+str_length, add_length, str_charset,
				  s, arg_length, cs);
  }
477 478
  else
  {
479 480
    if (realloc(str_length + arg_length)) 
      return TRUE;
481 482 483
    memcpy(Ptr + str_length, s, arg_length);
    str_length+= arg_length;
  }
484 485 486 487
  return FALSE;
}


488
#ifdef TO_BE_REMOVED
bk@work.mysql.com's avatar
bk@work.mysql.com committed
489 490 491 492 493 494 495 496 497 498 499 500
bool String::append(FILE* file, uint32 arg_length, myf my_flags)
{
  if (realloc(str_length+arg_length))
    return TRUE;
  if (my_fread(file, (byte*) Ptr + str_length, arg_length, my_flags))
  {
    shrink(str_length);
    return TRUE;
  }
  str_length+=arg_length;
  return FALSE;
}
501 502 503 504 505 506 507 508 509 510 511 512 513 514
#endif

bool String::append(IO_CACHE* file, uint32 arg_length)
{
  if (realloc(str_length+arg_length))
    return TRUE;
  if (my_b_read(file, (byte*) Ptr + str_length, arg_length))
  {
    shrink(str_length);
    return TRUE;
  }
  str_length+=arg_length;
  return FALSE;
}
bk@work.mysql.com's avatar
bk@work.mysql.com committed
515

516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532
bool String::append_with_prefill(const char *s,uint32 arg_length,
		 uint32 full_length, char fill_char)
{
  int t_length= arg_length > full_length ? arg_length : full_length;

  if (realloc(str_length + t_length))
    return TRUE;
  t_length= full_length - arg_length;
  if (t_length > 0)
  {
    bfill(Ptr+str_length, t_length, fill_char);
    str_length=str_length + t_length;
  }
  append(s, arg_length);
  return FALSE;
}

bk@work.mysql.com's avatar
bk@work.mysql.com committed
533 534
uint32 String::numchars()
{
535
  return str_charset->cset->numchars(str_charset, Ptr, Ptr+str_length);
bk@work.mysql.com's avatar
bk@work.mysql.com committed
536 537 538 539
}

int String::charpos(int i,uint32 offset)
{
540
  if (i<0) return i;
541
  return str_charset->cset->charpos(str_charset,Ptr+offset,Ptr+str_length,i);
bk@work.mysql.com's avatar
bk@work.mysql.com committed
542 543 544 545 546 547 548
}

int String::strstr(const String &s,uint32 offset)
{
  if (s.length()+offset <= str_length)
  {
    if (!s.length())
monty@donna.mysql.com's avatar
monty@donna.mysql.com committed
549
      return ((int) offset);	// Empty string is always found
bk@work.mysql.com's avatar
bk@work.mysql.com committed
550 551 552 553 554

    register const char *str = Ptr+offset;
    register const char *search=s.ptr();
    const char *end=Ptr+str_length-s.length()+1;
    const char *search_end=s.ptr()+s.length();
555
skip:
bk@work.mysql.com's avatar
bk@work.mysql.com committed
556 557 558 559 560 561 562
    while (str != end)
    {
      if (*str++ == *search)
      {
	register char *i,*j;
	i=(char*) str; j=(char*) search+1;
	while (j != search_end)
563
	  if (*i++ != *j++) goto skip;
bk@work.mysql.com's avatar
bk@work.mysql.com committed
564 565 566 567
	return (int) (str-Ptr) -1;
      }
    }
  }
568 569
  return -1;
}
bk@work.mysql.com's avatar
bk@work.mysql.com committed
570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585

/*
** Search string from end. Offset is offset to the end of string
*/

int String::strrstr(const String &s,uint32 offset)
{
  if (s.length() <= offset && offset <= str_length)
  {
    if (!s.length())
      return offset;				// Empty string is always found
    register const char *str = Ptr+offset-1;
    register const char *search=s.ptr()+s.length()-1;

    const char *end=Ptr+s.length()-2;
    const char *search_end=s.ptr()-1;
586
skip:
bk@work.mysql.com's avatar
bk@work.mysql.com committed
587 588 589 590 591 592 593
    while (str != end)
    {
      if (*str-- == *search)
      {
	register char *i,*j;
	i=(char*) str; j=(char*) search-1;
	while (j != search_end)
594
	  if (*i-- != *j--) goto skip;
bk@work.mysql.com's avatar
bk@work.mysql.com committed
595 596 597 598 599 600 601 602 603 604 605 606 607 608 609
	return (int) (i-Ptr) +1;
      }
    }
  }
  return -1;
}

/*
** replace substring with string
** If wrong parameter or not enough memory, do nothing
*/


bool String::replace(uint32 offset,uint32 arg_length,const String &to)
{
610 611 612 613 614 615 616
  return replace(offset,arg_length,to.ptr(),to.length());
}

bool String::replace(uint32 offset,uint32 arg_length,
                     const char *to,uint32 length)
{
  long diff = (long) length-(long) arg_length;
bk@work.mysql.com's avatar
bk@work.mysql.com committed
617 618 619 620
  if (offset+arg_length <= str_length)
  {
    if (diff < 0)
    {
621 622 623
      if (length)
	memcpy(Ptr+offset,to,length);
      bmove(Ptr+offset+length,Ptr+offset+arg_length,
bk@work.mysql.com's avatar
bk@work.mysql.com committed
624 625 626 627 628 629 630 631 632 633 634
	    str_length-offset-arg_length);
    }
    else
    {
      if (diff)
      {
	if (realloc(str_length+(uint32) diff))
	  return TRUE;
	bmove_upp(Ptr+str_length+diff,Ptr+str_length,
		  str_length-offset-arg_length);
      }
635 636
      if (length)
	memcpy(Ptr+offset,to,length);
bk@work.mysql.com's avatar
bk@work.mysql.com committed
637 638 639 640 641 642
    }
    str_length+=(uint32) diff;
  }
  return FALSE;
}

643

644 645 646 647 648 649 650 651 652 653 654
// added by Holyfoot for "geometry" needs
int String::reserve(uint32 space_needed, uint32 grow_by)
{
  if (Alloced_length < str_length + space_needed)
  {
    if (realloc(Alloced_length + max(space_needed, grow_by) - 1))
      return TRUE;
  }
  return FALSE;
}

655
void String::qs_append(const char *str, uint32 len)
656 657 658 659 660 661 662 663
{
  memcpy(Ptr + str_length, str, len + 1);
  str_length += len;
}

void String::qs_append(double d)
{
  char *buff = Ptr + str_length;
664
  str_length+= my_sprintf(buff, (buff, "%.14g", d));
665 666 667 668 669
}

void String::qs_append(double *d)
{
  double ld;
670
  float8get(ld, (char*) d);
671 672 673
  qs_append(ld);
}

bk@work.mysql.com's avatar
bk@work.mysql.com committed
674

monty@mysql.com's avatar
monty@mysql.com committed
675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694
/*
  Compare strings according to collation, without end space.

  SYNOPSIS
    sortcmp()
    s		First string
    t		Second string
    cs		Collation

  NOTE:
    Normally this is case sensitive comparison

  RETURN
  < 0	s < t
  0	s == t
  > 0	s > t
*/


int sortcmp(const String *s,const String *t, CHARSET_INFO *cs)
bk@work.mysql.com's avatar
bk@work.mysql.com committed
695
{
monty@mysql.com's avatar
monty@mysql.com committed
696
 return cs->coll->strnncollsp(cs,
monty@mysql.com's avatar
monty@mysql.com committed
697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720
                             (unsigned char *) s->ptr(),s->length(),
			     (unsigned char *) t->ptr(),t->length());
}


/*
  Compare strings byte by byte. End spaces are also compared.

  SYNOPSIS
    stringcmp()
    s		First string
    t		Second string

  NOTE:
    Strings are compared as a stream of unsigned chars

  RETURN
  < 0	s < t
  0	s == t
  > 0	s > t
*/


int stringcmp(const String *s,const String *t)
bk@work.mysql.com's avatar
bk@work.mysql.com committed
721
{
monty@mysql.com's avatar
monty@mysql.com committed
722 723 724
  uint32 s_len=s->length(),t_len=t->length(),len=min(s_len,t_len);
  int cmp= memcmp(s->ptr(), t->ptr(), len);
  return (cmp) ? cmp : (int) (s_len - t_len);
bk@work.mysql.com's avatar
bk@work.mysql.com committed
725 726 727 728 729 730 731 732 733 734 735 736 737 738
}


String *copy_if_not_alloced(String *to,String *from,uint32 from_length)
{
  if (from->Alloced_length >= from_length)
    return from;
  if (from->alloced || !to || from == to)
  {
    (void) from->realloc(from_length);
    return from;
  }
  if (to->realloc(from_length))
    return from;				// Actually an error
739 740
  if ((to->str_length=min(from->str_length,from_length)))
    memcpy(to->Ptr,from->Ptr,to->str_length);
741
  to->str_charset=from->str_charset;
bk@work.mysql.com's avatar
bk@work.mysql.com committed
742 743 744 745
  return to;
}


746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767
/****************************************************************************
  Help functions
****************************************************************************/

/*
  copy a string from one character set to another
  
  SYNOPSIS
    copy_and_convert()
    to			Store result here
    to_cs		Character set of result string
    from		Copy from here
    from_length		Length of from string
    from_cs		From character set

  NOTES
    'to' must be big enough as form_length * to_cs->mbmaxlen

  RETURN
    length of bytes copied to 'to'
*/

bk@work.mysql.com's avatar
bk@work.mysql.com committed
768

monty@mashka.mysql.fi's avatar
monty@mashka.mysql.fi committed
769
uint32
770 771 772 773 774 775 776 777
copy_and_convert(char *to, uint32 to_length, CHARSET_INFO *to_cs, 
		 const char *from, uint32 from_length, CHARSET_INFO *from_cs)
{
  int         cnvres;
  my_wc_t     wc;
  const uchar *from_end= (const uchar*) from+from_length;
  char *to_start= to;
  uchar *to_end= (uchar*) to+to_length;
778 779 780 781
  int (*mb_wc)(struct charset_info_st *, my_wc_t *, const uchar *,
	       const uchar *) = from_cs->cset->mb_wc;
  int (*wc_mb)(struct charset_info_st *, my_wc_t, uchar *s, uchar *e)=
    to_cs->cset->wc_mb;
782

783
  while (1)
784
  {
785
    if ((cnvres= (*mb_wc)(from_cs, &wc, (uchar*) from,
786
				      from_end)) > 0)
787 788 789 790 791 792 793 794 795 796
      from+= cnvres;
    else if (cnvres == MY_CS_ILSEQ)
    {
      from++;
      wc= '?';
    }
    else
      break;					// Impossible char.

outp:
797
    if ((cnvres= (*wc_mb)(to_cs, wc, (uchar*) to, to_end)) > 0)
798 799 800 801 802 803 804 805 806 807 808
      to+= cnvres;
    else if (cnvres == MY_CS_ILUNI && wc != '?')
    {
      wc= '?';
      goto outp;
    }
    else
      break;
  }
  return (uint32) (to - to_start);
}
bell@sanja.is.com.ua's avatar
bell@sanja.is.com.ua committed
809

810

bell@sanja.is.com.ua's avatar
bell@sanja.is.com.ua committed
811 812 813
void String::print(String *str)
{
  char *st= (char*)Ptr, *end= st+str_length;
814
  for (; st < end; st++)
bell@sanja.is.com.ua's avatar
bell@sanja.is.com.ua committed
815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841
  {
    uchar c= *st;
    switch (c)
    {
    case '\\':
      str->append("\\\\", 2);
      break;
    case '\0':
      str->append("\\0", 2);
      break;
    case '\'':
      str->append("\\'", 2);
      break;
    case '\n':
      str->append("\\n", 2);
      break;
    case '\r':
      str->append("\\r", 2);
      break;
    case 26: //Ctrl-Z
      str->append("\\z", 2);
      break;
    default:
      str->append(c);
    }
  }
}
842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861


/*
  Exchange state of this object and argument.

  SYNOPSIS
    String::swap()

  RETURN
    Target string will contain state of this object and vice versa.
*/

void String::swap(String &s)
{
  swap_variables(char *, Ptr, s.Ptr);
  swap_variables(uint32, str_length, s.str_length);
  swap_variables(uint32, Alloced_length, s.Alloced_length);
  swap_variables(bool, alloced, s.alloced);
  swap_variables(CHARSET_INFO*, str_charset, s.str_charset);
}