my_vsnprintf.c 17.1 KB
Newer Older
unknown's avatar
unknown committed
1 2 3 4
/* 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
unknown's avatar
unknown committed
5
   the Free Software Foundation; version 2 of the License.
unknown's avatar
unknown committed
6 7

   This program is distributed in the hope that it will be useful,
unknown's avatar
unknown committed
8
   but WITHOUT ANY WARRANTY; without even the implied warranty of
unknown's avatar
unknown committed
9 10 11 12 13 14
   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 */
unknown's avatar
unknown committed
15

16
#include <my_global.h>
unknown's avatar
unknown committed
17 18 19 20
#include <m_string.h>
#include <stdarg.h>
#include <m_ctype.h>

21

22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 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 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170
#define MAX_ARGS 32                           /* max positional args count*/
#define MAX_PRINT_INFO 32                     /* max print position count */

#define LENGTH_ARG     1
#define WIDTH_ARG      2
#define PREZERO_ARG    4
#define ESCAPED_ARG    8 

typedef struct pos_arg_info ARGS_INFO;
typedef struct print_info PRINT_INFO;

struct pos_arg_info
{
  char arg_type;                              /* argument type */
  uint have_longlong;                         /* used from integer values */
  char *str_arg;                              /* string value of the arg */
  longlong longlong_arg;                      /* integer value of the arg */
  double double_arg;                          /* double value of the arg */
};


struct print_info
{
  char arg_type;                              /* argument type */
  size_t arg_idx;                             /* index of the positional arg */
  size_t length;                              /* print width or arg index */
  size_t width;                               /* print width or arg index */
  uint flags;
  const char *begin;                          /**/
  const char *end;                            /**/
};


/**
  Calculates print length or index of positional argument

  @param fmt         processed string
  @param length      print length or index of positional argument
  @param pre_zero    returns flags with PREZERO_ARG set if necessary

  @retval
    string position right after length digits
*/

static const char *get_length(const char *fmt, size_t *length, uint *pre_zero)
{
  for (; my_isdigit(&my_charset_latin1, *fmt); fmt++)
  {
    *length= *length * 10 + (uint)(*fmt - '0');
    if (!*length)
      *pre_zero|= PREZERO_ARG;                  /* first digit was 0 */
  }
  return fmt;
}


/**
  Calculates print width or index of positional argument

  @param fmt         processed string
  @param width       print width or index of positional argument

  @retval
    string position right after width digits
*/

static const char *get_width(const char *fmt, size_t *width)
{
  for (; my_isdigit(&my_charset_latin1, *fmt); fmt++)
  {
    *width= *width * 10 + (uint)(*fmt - '0');
  }
  return fmt;
}

/**
  Calculates print width or index of positional argument

  @param fmt            processed string
  @param have_longlong  TRUE if longlong is required

  @retval
    string position right after modifier symbol
*/

static const char *check_longlong(const char *fmt, uint *have_longlong)
{
  *have_longlong= 0;
  if (*fmt == 'l')
  {
    fmt++;
    if (*fmt != 'l')
      *have_longlong= (sizeof(long) == sizeof(longlong));
    else
    {
      fmt++;
      *have_longlong= 1;
    }
  }
  else if (*fmt == 'z')
  {
    fmt++;
    *have_longlong= (sizeof(size_t) == sizeof(longlong));
  }
  return fmt;
}


/**
  Returns escaped string

  @param cs         string charset
  @param to         buffer where escaped string will be placed
  @param end        end of buffer
  @param par        string to escape
  @param par_len    string length
  @param quote_char character for quoting

  @retval
    position in buffer which points on the end of escaped string
*/

static char *backtick_string(CHARSET_INFO *cs, char *to, char *end,
                             char *par, size_t par_len, char quote_char)
{
  uint char_len;
  char *start= to;
  char *par_end= par + par_len;
  size_t buff_length= (size_t) (end - to);

  if (buff_length <= par_len)
    goto err;
  *start++= quote_char;

  for ( ; par < par_end; par+= char_len)
  {
    uchar c= *(uchar *) par;
    if (!(char_len= my_mbcharlen(cs, c)))
      char_len= 1;
    if (char_len == 1 && c == (uchar) quote_char )
    {
      if (start + 1 >= end)
        goto err;
      *start++= quote_char;
    }
    if (start + char_len >= end)
      goto err;
    start= strnmov(start, par, char_len);
  }
171
    
172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474
  if (start + 1 >= end)
    goto err;
  *start++= quote_char;
  return start;

err:
    *to='\0';
  return to;
}


/**
  Prints string argument
*/

static char *process_str_arg(CHARSET_INFO *cs, char *to, char *end,
                             size_t width, char *par, uint print_type)
{
  int well_formed_error;
  size_t plen, left_len= (size_t) (end - to) + 1;
  if (!par)
    par = (char*) "(null)";

  plen= strnlen(par, width);
  if (left_len <= plen)
    plen = left_len - 1;
  plen= cs->cset->well_formed_len(cs, par, par + plen,
                                  width, &well_formed_error);
  if (print_type & ESCAPED_ARG)
    to= backtick_string(cs, to, end, par, plen, '`');
  else
    to= strnmov(to,par,plen);
  return to;
}


/**
  Prints binary argument
*/

static char *process_bin_arg(char *to, char *end, size_t width, char *par)
{
  DBUG_ASSERT(to <= end);
  if (to + width + 1 > end)
    width= end - to - 1;  /* sign doesn't matter */
  memmove(to, par, width);
  to+= width;
  return to;
}


/**
  Prints integer argument
*/

static char *process_int_arg(char *to, char *end, size_t length,
                             longlong par, char arg_type, uint print_type)
{
  size_t res_length, to_length;
  char *store_start= to, *store_end;
  char buff[32];

  if ((to_length= (size_t) (end-to)) < 16 || length)
    store_start= buff;

  if (arg_type == 'd')
    store_end= int10_to_str(par, store_start, -10);
  else if (arg_type == 'u')
    store_end= int10_to_str(par, store_start, 10);
  else if (arg_type == 'p')
  {
    store_start[0]= '0';
    store_start[1]= 'x';
    store_end= int2str(par, store_start + 2, 16, 0);
  }
  else
  {
    DBUG_ASSERT(arg_type == 'X' || arg_type =='x');
    store_end= int2str(par, store_start, 16, (arg_type == 'X'));
  }

  if ((res_length= (size_t) (store_end - store_start)) > to_length)
    return to;                           /* num doesn't fit in output */
  /* If %#d syntax was used, we have to pre-zero/pre-space the string */
  if (store_start == buff)
  {
    length= min(length, to_length);
    if (res_length < length)
    {
      size_t diff= (length- res_length);
      bfill(to, diff, (print_type & PREZERO_ARG) ? '0' : ' ');
      to+= diff;
    }
    bmove(to, store_start, res_length);
  }
  to+= res_length;
  return to;
}


/**
  Procesed positional arguments.

  @param cs         string charset
  @param to         buffer where processed string will be place
  @param end        end of buffer
  @param par        format string
  @param arg_index  arg index of the first occurrence of positional arg
  @param ap         list of parameters

  @retval
    end of buffer where processed string is placed
*/

static char *process_args(CHARSET_INFO *cs, char *to, char *end,
                          const char* fmt, size_t arg_index, va_list ap)
{
  ARGS_INFO args_arr[MAX_ARGS];
  PRINT_INFO print_arr[MAX_PRINT_INFO];
  uint idx= 0, arg_count= arg_index;

start:
  /* Here we are at the beginning of positional argument, right after $ */
  arg_index--;
  print_arr[idx].flags= 0;
  if (*fmt == '`')
  {
    print_arr[idx].flags|= ESCAPED_ARG;
    fmt++;
  }
  if (*fmt == '-')
    fmt++;
  print_arr[idx].length= print_arr[idx].width= 0;
  /* Get print length */
  if (*fmt == '*')
  {          
    fmt++;
    fmt= get_length(fmt, &print_arr[idx].length, &print_arr[idx].flags);
    print_arr[idx].length--;    
    DBUG_ASSERT(*fmt == '$' && print_arr[idx].length < MAX_ARGS);
    args_arr[print_arr[idx].length].arg_type= 'd';
    print_arr[idx].flags|= LENGTH_ARG;
    arg_count= max(arg_count, print_arr[idx].length + 1);
    fmt++;
  }
  else
    fmt= get_length(fmt, &print_arr[idx].length, &print_arr[idx].flags);
  
  if (*fmt == '.')
  {
    fmt++;
    /* Get print width */
    if (*fmt == '*')
    {
      fmt= get_width(fmt, &print_arr[idx].width);
      print_arr[idx].width--;
      DBUG_ASSERT(*fmt == '$' && print_arr[idx].width < MAX_ARGS);
      args_arr[print_arr[idx].width].arg_type= 'd';
      print_arr[idx].flags|= WIDTH_ARG;
      arg_count= max(arg_count, print_arr[idx].width + 1);
      fmt++;
    }
    else
      fmt= get_width(fmt, &print_arr[idx].width);
  }
  else
    print_arr[idx].width= SIZE_T_MAX;

  fmt= check_longlong(fmt, &args_arr[arg_index].have_longlong);
  if (*fmt == 'p')
    args_arr[arg_index].have_longlong= (sizeof(void *) == sizeof(longlong));
  args_arr[arg_index].arg_type= print_arr[idx].arg_type= *fmt;
  
  print_arr[idx].arg_idx= arg_index;
  print_arr[idx].begin= ++fmt;

  while (*fmt && *fmt != '%')
    fmt++;

  if (!*fmt)                                  /* End of format string */
  {
    uint i;
    print_arr[idx].end= fmt;
    /* Obtain parameters from the list */
    for (i= 0 ; i < arg_count; i++)
    {
      switch (args_arr[i].arg_type) {
      case 's':
      case 'b':
        args_arr[i].str_arg= va_arg(ap, char *);
        break;
      case 'f':
      case 'g':
        args_arr[i].double_arg= va_arg(ap, double);
        break;
      case 'd':
      case 'u':
      case 'x':
      case 'X':
      case 'p':
        if (args_arr[i].have_longlong)
          args_arr[i].longlong_arg= va_arg(ap,longlong);
        else if (args_arr[i].arg_type == 'd')
          args_arr[i].longlong_arg= va_arg(ap, int);
        else
          args_arr[i].longlong_arg= va_arg(ap, uint);
        break;
      case 'c':
        args_arr[i].longlong_arg= va_arg(ap, int);
        break;
      default:
        DBUG_ASSERT(0);
      }
    }
    /* Print result string */
    for (i= 0; i <= idx; i++)
    {
      uint width= 0, length= 0;
      switch (print_arr[i].arg_type) {
      case 's':
      {
        char *par= args_arr[print_arr[i].arg_idx].str_arg;
        width= (print_arr[i].flags & WIDTH_ARG) ?
          args_arr[print_arr[i].width].longlong_arg : print_arr[i].width;
        to= process_str_arg(cs, to, end, width, par, print_arr[i].flags);
        break;
      }
      case 'b':
      {
        char *par = args_arr[print_arr[i].arg_idx].str_arg;
        width= (print_arr[i].flags & WIDTH_ARG) ?
          args_arr[print_arr[i].width].longlong_arg : print_arr[i].width;
        to= process_bin_arg(to, end, width, par);
        break;
      }
      case 'c':
      {
        if (to == end)
          break;
        *to++= (char) args_arr[print_arr[i].arg_idx].longlong_arg;
        break;
      }
      case 'd':
      case 'u':
      case 'x':
      case 'X':
      case 'p':
      {
        /* Integer parameter */
        longlong larg;
        length= (print_arr[i].flags & LENGTH_ARG) ?
          args_arr[print_arr[i].length].longlong_arg : print_arr[i].length;

        if (args_arr[print_arr[i].arg_idx].have_longlong)
          larg = args_arr[print_arr[i].arg_idx].longlong_arg;
        else if (print_arr[i].arg_type == 'd')
          larg = (int) args_arr[print_arr[i].arg_idx].longlong_arg;
        else
          larg= (uint) args_arr[print_arr[i].arg_idx].longlong_arg;

        to= process_int_arg(to, end, length, larg, print_arr[i].arg_type,
                            print_arr[i].flags);
        break;
      }
      default:
        break;
      }

      if (to == end)
        break;

      length= min(end - to , print_arr[i].end - print_arr[i].begin);
      if (to + length < end)
        length++;
      to= strnmov(to, print_arr[i].begin, length);
    }
    DBUG_ASSERT(to <= end);
    *to='\0';				/* End of errmessage */
    return to;
  }
  else
  {
    /* Process next positional argument*/
    DBUG_ASSERT(*fmt == '%');
    print_arr[idx].end= fmt - 1;
    idx++;
    fmt++;
    arg_index= 0;
    fmt= get_width(fmt, &arg_index);
    DBUG_ASSERT(*fmt == '$');
    fmt++;
    arg_count= max(arg_count, arg_index);
    goto start;
  }
  DBUG_ASSERT(0);
  return 0;
}



/**
  Produces output string according to a format string

475 476
  See the detailed documentation around my_snprintf_service_st

477 478 479 480 481 482 483
  @param cs         string charset
  @param to         buffer where processed string will be place
  @param n          size of buffer
  @param par        format string
  @param ap         list of parameters

  @retval
484 485 486
    length of result string
*/

487 488
size_t my_vsnprintf_ex(CHARSET_INFO *cs, char *to, size_t n,
                       const char* fmt, va_list ap)
unknown's avatar
unknown committed
489
{
490
  char *start=to, *end=to+n-1;
491
  size_t length, width;
492
  uint print_type, have_longlong;
493

494
  for (; *fmt ; fmt++)
unknown's avatar
unknown committed
495
  {
unknown's avatar
unknown committed
496
    if (*fmt != '%')
unknown's avatar
unknown committed
497
    {
498
      if (to == end)                            /* End of buffer */
unknown's avatar
unknown committed
499
	break;
500
      *to++= *fmt;                            /* Copy ordinary char */
unknown's avatar
unknown committed
501 502
      continue;
    }
503
    fmt++;					/* skip '%' */
504

505
    length= width= 0;
506 507 508 509
    print_type= 0;

    /* Read max fill size (only used with %d and %u) */
    if (my_isdigit(&my_charset_latin1, *fmt))
510
    {
511 512 513 514 515 516
      fmt= get_length(fmt, &length, &print_type);
      if (*fmt == '$')
      {
        to= process_args(cs, to, end, (fmt+1), length, ap);
        return (size_t) (to - start);
      }
517
    }
518
    else
519 520 521 522 523 524 525 526 527
    {
      if (*fmt == '`')
      {
        print_type|= ESCAPED_ARG;
        fmt++;
      }
      if (*fmt == '-')
        fmt++;
      if (*fmt == '*')
528
      {
529 530
        fmt++;
        length= va_arg(ap, int);
531
      }
532 533 534 535
      else
        fmt= get_length(fmt, &length, &print_type);
    }

unknown's avatar
unknown committed
536
    if (*fmt == '.')
537 538 539 540 541 542 543 544
    {
      fmt++;
      if (*fmt == '*')
      {
        fmt++;
        width= va_arg(ap, int);
      }
      else
545
        fmt= get_width(fmt, &width);
546
    }
unknown's avatar
unknown committed
547
    else
548 549 550 551
      width= SIZE_T_MAX;   

    fmt= check_longlong(fmt, &have_longlong);

552
    if (*fmt == 's')				/* String parameter */
unknown's avatar
unknown committed
553
    {
554 555
      reg2 char *par= va_arg(ap, char *);
      to= process_str_arg(cs, to, end, width, par, print_type);
556
      continue;
unknown's avatar
unknown committed
557
    }
unknown's avatar
unknown committed
558 559 560
    else if (*fmt == 'b')				/* Buffer parameter */
    {
      char *par = va_arg(ap, char *);
561
      to= process_bin_arg(to, end, width, par);
unknown's avatar
unknown committed
562 563
      continue;
    }
564 565
    else if (*fmt == 'd' || *fmt == 'u' || *fmt == 'x' || *fmt == 'X' ||
             *fmt == 'p')
566
    {
567 568 569 570 571 572 573 574 575
      /* Integer parameter */
      longlong larg;
      if (*fmt == 'p')
        have_longlong= (sizeof(void *) == sizeof(longlong));

      if (have_longlong)
        larg = va_arg(ap,longlong);
      else if (*fmt == 'd')
        larg = va_arg(ap, int);
576
      else
577 578 579
        larg= va_arg(ap, uint);

      to= process_int_arg(to, end, length, larg, *fmt, print_type);
580 581
      continue;
    }
unknown's avatar
unknown committed
582 583 584 585 586 587 588 589 590 591
    else if (*fmt == 'c')                       /* Character parameter */
    {
      register int larg;
      if (to == end)
        break;
      larg = va_arg(ap, int);
      *to++= (char) larg;
      continue;
    }

592 593 594 595
    /* We come here on '%%', unknown code or too long parameter */
    if (to == end)
      break;
    *to++='%';				/* % used as % or unknown code */
unknown's avatar
unknown committed
596
  }
unknown's avatar
unknown committed
597
  DBUG_ASSERT(to <= end);
598
  *to='\0';				/* End of errmessage */
599
  return (size_t) (to - start);
unknown's avatar
unknown committed
600
}
unknown's avatar
unknown committed
601

602

603 604 605 606 607 608 609 610 611 612 613 614 615
/*
  Limited snprintf() implementations

  exported to plugins as a service, see the detailed documentation
  around my_snprintf_service_st
*/

size_t my_vsnprintf(char *to, size_t n, const char* fmt, va_list ap)
{
  return my_vsnprintf_ex(&my_charset_latin1, to, n, fmt, ap);
}


616
size_t my_snprintf(char* to, size_t n, const char* fmt, ...)
617
{
618
  size_t result;
619 620 621 622 623 624
  va_list args;
  va_start(args,fmt);
  result= my_vsnprintf(to, n, fmt, args);
  va_end(args);
  return result;
}
625

unknown's avatar
unknown committed
626
#ifdef MAIN
unknown's avatar
unknown committed
627
#define OVERRUN_SENTRY  250
unknown's avatar
unknown committed
628 629
static void my_printf(const char * fmt, ...)
{
unknown's avatar
unknown committed
630
  char buf[33];
unknown's avatar
unknown committed
631 632 633
  int n;
  va_list ar;
  va_start(ar, fmt);
unknown's avatar
unknown committed
634 635
  buf[sizeof(buf)-1]=OVERRUN_SENTRY;
  n = my_vsnprintf(buf, sizeof(buf)-1,fmt, ar);
unknown's avatar
unknown committed
636 637
  printf(buf);
  printf("n=%d, strlen=%d\n", n, strlen(buf));
638
  if ((uchar) buf[sizeof(buf)-1] != OVERRUN_SENTRY)
unknown's avatar
unknown committed
639 640 641 642
  {
    fprintf(stderr, "Buffer overrun\n");
    abort();
  }
unknown's avatar
unknown committed
643 644 645
  va_end(ar);
}

646

unknown's avatar
unknown committed
647 648
int main()
{
unknown's avatar
unknown committed
649

unknown's avatar
unknown committed
650 651 652 653 654 655 656 657 658
  my_printf("Hello\n");
  my_printf("Hello int, %d\n", 1);
  my_printf("Hello string '%s'\n", "I am a string");
  my_printf("Hello hack hack hack hack hack hack hack %d\n", 1);
  my_printf("Hello %d hack  %d\n", 1, 4);
  my_printf("Hello %d hack hack hack hack hack %d\n", 1, 4);
  my_printf("Hello '%s' hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh\n", "hack");
  my_printf("Hello hhhhhhhhhhhhhh %d sssssssssssssss\n", 1);
  my_printf("Hello  %u\n", 1);
659
  my_printf("Hex:   %lx  '%6lx'\n", 32, 65);
unknown's avatar
unknown committed
660 661
  my_printf("conn %ld to: '%-.64s' user: '%-.32s' host:\
 `%-.64s' (%-.64s)", 1, 0,0,0,0);
662 663 664 665 666 667 668 669 670 671 672 673

  my_printf("Hello string %`s\n", "I am a string");
  my_printf("Hello %05s\n", "TEST");
  my_printf("My %1$`-.1s test\n", "QQQQ");
  my_printf("My %1$s test done %2$s\n", "DDDD", "AAAA");
  my_printf("My %1$s test %2$s, %1$-.3s\n", "DDDD", "CCCC");
  my_printf("My %1$`-.4b test\n", "QQQQ");
  my_printf("My %1$c test\n", 'X');
  my_printf("My `%010d` test1 %4x test2 %4X\n", 10, 10, 10);
  my_printf("My `%1$010d` test1 %2$4x test2 %2$4x\n", 10, 10);
  my_printf("My %1$*02$d test\n", 10, 5);
  my_printf("My %1$`s test %2$s, %1$`-.3s\n", "DDDD", "CCCC");
unknown's avatar
unknown committed
674 675 676
  return 0;
}
#endif