libs/basekit/source/PortableSnprintf.c

   1 /*
   2  * Copyright Patrick Powell 1995
   3  * This code is based on code written by Patrick Powell (papowell@astart.com)
   4  * It may be used for any purpose as long as this notice remains intact
   5  * on all source code distributions
   6  */
   7
   8 /**************************************************************
   9  * Original:
  10  * Patrick Powell Tue Apr 11 09:48:21 PDT 1995
  11  * A bombproof version of doprnt (dopr) included.
  12  * Sigh.  This sort of thing is always nasty do deal with.  Note that
  13  * the version here does not include floating point...
  14  *
  15  * snprintf() is used instead of sprintf() as it does limit checks
  16  * for string length.  This covers a nasty loophole.
  17  *
  18  * The other functions are there to prevent NULL pointers from
  19  * causing nast effects.
  20  *
  21  * More Recently:
  22  *  Brandon Long <blong@fiction.net> 9/15/96 for mutt 0.43
  23  *  This was ugly.  It is still ugly.  I opted out of floating point
  24  *  numbers, but the formatter understands just about everything
  25  *  from the normal C string format, at least as far as I can tell from
  26  *  the Solaris 2.5 printf(3S) man page.
  27  *
  28  *  Brandon Long <blong@fiction.net> 10/22/97 for mutt 0.87.1
  29  *    Ok, added some minimal floating point support, which means this
  30  *    probably requires libm on most operating systems.  Don't yet
  31  *    support the exponent (e,E) and sigfig (g,G).  Also, fmtint()
  32  *    was pretty badly broken, it just wasn't being exercised in ways
  33  *    which showed it, so that's been fixed.  Also, formated the code
  34  *    to mutt conventions, and removed dead code left over from the
  35  *    original.  Also, there is now a builtin-test, just compile with:
  36  *           gcc -DTEST_SNPRINTF -o snprintf snprintf.c -lm
  37  *    and run snprintf for results.
  38  *
  39  *  Thomas Roessler <roessler@guug.de> 01/27/98 for mutt 0.89i
  40  *    The PGP code was using unsigned hexadecimal formats.
  41  *    Unfortunately, unsigned formats simply didn't work.
  42  *
  43  *  Michael Elkins <me@cs.hmc.edu> 03/05/98 for mutt 0.90.8
  44  *    The original code assumed that both snprintf() and vsnprintf() were
  45  *    missing.  Some systems only have snprintf() but not vsnprintf(), so
  46  *    the code is now broken down under HAVE_SNPRINTF and HAVE_VSNPRINTF.
  47  *
  48  *  Andrew Tridgell (tridge@samba.org) Oct 1998
  49  *    fixed handling of %.0f
  50  *    added test for HAVE_LONG_DOUBLE
  51  *
  52  * tridge@samba.org, idra@samba.org, April 2001
  53  *    got rid of fcvt code (twas buggy and made testing harder)
  54  *    added C99 semantics
  55  *
  56  **************************************************************/
  57
  58 #include <string.h>
  59 #include <ctype.h>
  60 #include <sys/types.h>
  61 #include <stdarg.h>
  62 #include <stdlib.h>
  63
  64 #define NO_CONFIG_H 1
  65 #define HAVE_STRING_H 1
  66 #define HAVE_CTYPE_H 1
  67 #define HAVE_STDLIB_H 1
  68
  69 #define HAVE_SNPRINTF 1
  70 #define HAVE_VSNPRINTF 1
  71 #define HAVE_C99_VSNPRINTF 1
  72
  73 #define HAVE_LONG_DOUBLE 1
  74 #define HAVE_LONG_LONG 1
  75 #define HAVE_SNPRINTF 1
  76 #define HAVE_C99_VSNPRINTF 1
  77 #define HAVE_ASPRINTF 1
  78 #define HAVE_VASPRINTF 1
  79
  80 #ifndef NO_CONFIG_H
  81 #include "config.h"
  82 #endif
  83
  84 #ifdef HAVE_STRING_H
  85 #include <string.h>
  86 #endif
  87
  88 #ifdef HAVE_STRINGS_H
  89 #include <strings.h>
  90 #endif
  91 #ifdef HAVE_CTYPE_H
  92 #include <ctype.h>
  93 #endif
  94 #include <sys/types.h>
  95 #include <stdarg.h>
  96 #ifdef HAVE_STDLIB_H
  97 #include <stdlib.h>
  98 #endif
  99
 100 #if defined(HAVE_SNPRINTF) && defined(HAVE_VSNPRINTF) && defined(HAVE_C99_VSNPRINTF)
 101 /* only include stdio.h if we are not re-defining snprintf or vsnprintf */
 102 #include <stdio.h>
 103 /* make the compiler happy with an empty file */
 104 void dummy_snprintf(void) {}
 105 #else
 106
 107 #ifdef HAVE_LONG_DOUBLE
 108 #define LDOUBLE long double
 109 #else
 110 #define LDOUBLE double
 111 #endif
 112
 113 #ifdef HAVE_LONG_LONG
 114 #define LLONG long long
 115 #else
 116 #define LLONG long
 117 #endif
 118
 119 static size_t dopr(char *buffer, size_t maxlen, const char *format,
 120                    va_list args);
 121 static void fmtstr(char *buffer, size_t *currlen, size_t maxlen,
 122                    char *value, int flags, int min, int max);
 123 static void fmtint(char *buffer, size_t *currlen, size_t maxlen,
 124                    long value, int base, int min, int max, int flags);
 125 static void fmtfp(char *buffer, size_t *currlen, size_t maxlen,
 126                   LDOUBLE fvalue, int min, int max, int flags);
 127 static void dopr_outch(char *buffer, size_t *currlen, size_t maxlen, char c);
 128
 129 /*
 130  * dopr(): poor man's version of doprintf
 131  */
 132
 133 /* format read states */
 134 #define DP_S_DEFAULT 0
 135 #define DP_S_FLAGS   1
 136 #define DP_S_MIN     2
 137 #define DP_S_DOT     3
 138 #define DP_S_MAX     4
 139 #define DP_S_MOD     5
 140 #define DP_S_CONV    6
 141 #define DP_S_DONE    7
 142
 143 /* format flags - Bits */
 144 #define DP_F_MINUS      (1 << 0)
 145 #define DP_F_PLUS       (1 << 1)
 146 #define DP_F_SPACE      (1 << 2)
 147 #define DP_F_NUM        (1 << 3)
 148 #define DP_F_ZERO       (1 << 4)
 149 #define DP_F_UP         (1 << 5)
 150 #define DP_F_UNSIGNED   (1 << 6)
 151
 152 /* Conversion Flags */
 153 #define DP_C_SHORT   1
 154 #define DP_C_LONG    2
 155 #define DP_C_LDOUBLE 3
 156 #define DP_C_LLONG   4
 157
 158 #define char_to_int(p) ((p)- '0')
 159 #ifndef MAX
 160 #define MAX(p,q) (((p) >= (q)) ? (p) : (q))
 161 #endif
 162
 163 static size_t dopr(char *buffer, size_t maxlen, const char *format, va_list args)
 164 {
 165     char ch;
 166     LLONG value;
 167     LDOUBLE fvalue;
 168     char *strvalue;
 169     int min;
 170     int max;
 171     int state;
 172     int flags;
 173     int cflags;
 174     size_t currlen;
 175
 176     state = DP_S_DEFAULT;
 177     currlen = flags = cflags = min = 0;
 178     max = -1;
 179     ch = *format++;
 180
 181     while (state != DP_S_DONE) {
 182         if (ch == '\0')
 183             state = DP_S_DONE;
 184
 185         switch(state) {
 186         case DP_S_DEFAULT:
 187             if (ch == '%')
 188                 state = DP_S_FLAGS;
 189             else
 190                 dopr_outch (buffer, &currlen, maxlen, ch);
 191             ch = *format++;
 192             break;
 193         case DP_S_FLAGS:
 194             switch (ch) {
 195             case '-':
 196                 flags |= DP_F_MINUS;
 197                 ch = *format++;
 198                 break;
 199             case '+':
 200                 flags |= DP_F_PLUS;
 201                 ch = *format++;
 202                 break;
 203             case ' ':
 204                 flags |= DP_F_SPACE;
 205                 ch = *format++;
 206                 break;
 207             case '#':
 208                 flags |= DP_F_NUM;
 209                 ch = *format++;
 210                 break;
 211             case '0':
 212                 flags |= DP_F_ZERO;
 213                 ch = *format++;
 214                 break;
 215             default:
 216                 state = DP_S_MIN;
 217                 break;
 218             }
 219             break;
 220         case DP_S_MIN:
 221             if (isdigit((unsigned char)ch)) {
 222                 min = 10*min + char_to_int (ch);
 223                 ch = *format++;
 224             } else if (ch == '*') {
 225                 min = va_arg (args, int);
 226                 ch = *format++;
 227                 state = DP_S_DOT;
 228             } else {
 229                 state = DP_S_DOT;
 230             }
 231             break;
 232         case DP_S_DOT:
 233             if (ch == '.') {
 234                 state = DP_S_MAX;
 235                 ch = *format++;
 236             } else {
 237                 state = DP_S_MOD;
 238             }
 239             break;
 240         case DP_S_MAX:
 241             if (isdigit((unsigned char)ch)) {
 242                 if (max < 0)
 243                     max = 0;
 244                 max = 10*max + char_to_int (ch);
 245                 ch = *format++;
 246             } else if (ch == '*') {
 247                 max = va_arg (args, int);
 248                 ch = *format++;
 249                 state = DP_S_MOD;
 250             } else {
 251                 state = DP_S_MOD;
 252             }
 253             break;
 254         case DP_S_MOD:
 255             switch (ch) {
 256             case 'h':
 257                 cflags = DP_C_SHORT;
 258                 ch = *format++;
 259                 break;
 260             case 'l':
 261                 cflags = DP_C_LONG;
 262                 ch = *format++;
 263                 if (ch == 'l') {        /* It's a long long */
 264                     cflags = DP_C_LLONG;
 265                     ch = *format++;
 266                 }
 267                 break;
 268             case 'L':
 269                 cflags = DP_C_LDOUBLE;
 270                 ch = *format++;
 271                 break;
 272             default:
 273                 break;
 274             }
 275             state = DP_S_CONV;
 276             break;
 277         case DP_S_CONV:
 278             switch (ch) {
 279             case 'd':
 280             case 'i':
 281                 if (cflags == DP_C_SHORT)
 282                     value = va_arg (args, int);
 283                 else if (cflags == DP_C_LONG)
 284                     value = va_arg (args, long int);
 285                 else if (cflags == DP_C_LLONG)
 286                     value = va_arg (args, LLONG);
 287                 else
 288                     value = va_arg (args, int);
 289                 fmtint (buffer, &currlen, maxlen, value, 10, min, max, flags);
 290                 break;
 291             case 'o':
 292                 flags |= DP_F_UNSIGNED;
 293                 if (cflags == DP_C_SHORT)
 294                     value = va_arg (args, unsigned int);
 295                 else if (cflags == DP_C_LONG)
 296                     value = (long)va_arg (args, unsigned long int);
 297                 else if (cflags == DP_C_LLONG)
 298                     value = (long)va_arg (args, unsigned LLONG);
 299                 else
 300                     value = (long)va_arg (args, unsigned int);
 301                 fmtint (buffer, &currlen, maxlen, value, 8, min, max, flags);
 302                 break;
 303             case 'u':
 304                 flags |= DP_F_UNSIGNED;
 305                 if (cflags == DP_C_SHORT)
 306                     value = va_arg (args, unsigned int);
 307                 else if (cflags == DP_C_LONG)
 308                     value = (long)va_arg (args, unsigned long int);
 309                 else if (cflags == DP_C_LLONG)
 310                     value = (LLONG)va_arg (args, unsigned LLONG);
 311                 else
 312                     value = (long)va_arg (args, unsigned int);
 313                 fmtint (buffer, &currlen, maxlen, value, 10, min, max, flags);
 314                 break;
 315             case 'X':
 316                 flags |= DP_F_UP;
 317             case 'x':
 318                 flags |= DP_F_UNSIGNED;
 319                 if (cflags == DP_C_SHORT)
 320                     value = va_arg (args, unsigned int);
 321                 else if (cflags == DP_C_LONG)
 322                     value = (long)va_arg (args, unsigned long int);
 323                 else if (cflags == DP_C_LLONG)
 324                     value = (LLONG)va_arg (args, unsigned LLONG);
 325                 else
 326                     value = (long)va_arg (args, unsigned int);
 327                 fmtint (buffer, &currlen, maxlen, value, 16, min, max, flags);
 328                 break;
 329             case 'f':
 330                 if (cflags == DP_C_LDOUBLE)
 331                     fvalue = va_arg (args, LDOUBLE);
 332                 else
 333                     fvalue = va_arg (args, double);
 334                 /* um, floating point? */
 335                 fmtfp (buffer, &currlen, maxlen, fvalue, min, max, flags);
 336                 break;
 337             case 'E':
 338                 flags |= DP_F_UP;
 339             case 'e':
 340                 if (cflags == DP_C_LDOUBLE)
 341                     fvalue = va_arg (args, LDOUBLE);
 342                 else
 343                     fvalue = va_arg (args, double);
 344                 break;
 345             case 'G':
 346                 flags |= DP_F_UP;
 347             case 'g':
 348                 if (cflags == DP_C_LDOUBLE)
 349                     fvalue = va_arg (args, LDOUBLE);
 350                 else
 351                     fvalue = va_arg (args, double);
 352                 break;
 353             case 'c':
 354                 dopr_outch (buffer, &currlen, maxlen, va_arg (args, int));
 355                 break;
 356             case 's':
 357                 strvalue = va_arg (args, char *);
 358                 if (max == -1) {
 359                     max = strlen(strvalue);
 360                 }
 361                 if (min > 0 && max >= 0 && min > max) max = min;
 362                 fmtstr (buffer, &currlen, maxlen, strvalue, flags, min, max);
 363                 break;
 364             case 'p':
 365                 strvalue = va_arg (args, void *);
 366                 fmtint (buffer, &currlen, maxlen, (long) strvalue, 16, min, max, flags);
 367                 break;
 368             case 'n':
 369                 if (cflags == DP_C_SHORT) {
 370                     short int *num;
 371                     num = va_arg (args, short int *);
 372                     *num = currlen;
 373                 } else if (cflags == DP_C_LONG) {
 374                     long int *num;
 375                     num = va_arg (args, long int *);
 376                     *num = (long int)currlen;
 377                 } else if (cflags == DP_C_LLONG) {
 378                     LLONG *num;
 379                     num = va_arg (args, LLONG *);
 380                     *num = (LLONG)currlen;
 381                 } else {
 382                     int *num;
 383                     num = va_arg (args, int *);
 384                     *num = currlen;
 385                 }
 386                 break;
 387             case '%':
 388                 dopr_outch (buffer, &currlen, maxlen, ch);
 389                 break;
 390             case 'w':
 391                 /* not supported yet, treat as next char */
 392                 ch = *format++;
 393                 break;
 394             default:
 395                 /* Unknown, skip */
 396                 break;
 397             }
 398             ch = *format++;
 399             state = DP_S_DEFAULT;
 400             flags = cflags = min = 0;
 401             max = -1;
 402             break;
 403         case DP_S_DONE:
 404             break;
 405         default:
 406             /* hmm? */
 407             break; /* some picky compilers need this */
 408         }
 409     }
 410     if (maxlen != 0) {
 411         if (currlen < maxlen - 1)
 412             buffer[currlen] = '\0';
 413         else if (maxlen > 0)
 414             buffer[maxlen - 1] = '\0';
 415     }
 416
 417     return currlen;
 418 }
 419
 420 static void fmtstr(char *buffer, size_t *currlen, size_t maxlen,
 421                    char *value, int flags, int min, int max)
 422 {
 423     int padlen, strln;     /* amount to pad */
 424     int cnt = 0;
 425
 426 #ifdef DEBUG_SNPRINTF
 427     printf("fmtstr min=%d max=%d s=[%s]\n", min, max, value);
 428 #endif
 429     if (value == 0) {
 430         value = "<NULL>";
 431     }
 432
 433     for (strln = 0; value[strln]; ++strln); /* strlen */
 434     padlen = min - strln;
 435     if (padlen < 0)
 436         padlen = 0;
 437     if (flags & DP_F_MINUS)
 438         padlen = -padlen; /* Left Justify */
 439
 440     while ((padlen > 0) && (cnt < max)) {
 441         dopr_outch (buffer, currlen, maxlen, ' ');
 442         --padlen;
 443         ++cnt;
 444     }
 445     while (*value && (cnt < max)) {
 446         dopr_outch (buffer, currlen, maxlen, *value++);
 447         ++cnt;
 448     }
 449     while ((padlen < 0) && (cnt < max)) {
 450         dopr_outch (buffer, currlen, maxlen, ' ');
 451         ++padlen;
 452         ++cnt;
 453     }
 454 }
 455
 456 /* Have to handle DP_F_NUM (ie 0x and 0 alternates) */
 457
 458 static void fmtint(char *buffer, size_t *currlen, size_t maxlen,
 459                    long value, int base, int min, int max, int flags)
 460 {
 461     int signvalue = 0;
 462     unsigned long uvalue;
 463     char convert[20];
 464     int place = 0;
 465     int spadlen = 0; /* amount to space pad */
 466     int zpadlen = 0; /* amount to zero pad */
 467     int caps = 0;
 468
 469     if (max < 0)
 470         max = 0;
 471
 472     uvalue = value;
 473
 474     if(!(flags & DP_F_UNSIGNED)) {
 475         if( value < 0 ) {
 476             signvalue = '-';
 477             uvalue = -value;
 478         } else {
 479             if (flags & DP_F_PLUS)  /* Do a sign (+/i) */
 480                 signvalue = '+';
 481             else if (flags & DP_F_SPACE)
 482                 signvalue = ' ';
 483         }
 484     }
 485
 486     if (flags & DP_F_UP) caps = 1; /* Should characters be upper case? */
 487
 488     do {
 489         convert[place++] =
 490             (caps? "0123456789ABCDEF":"0123456789abcdef")
 491             [uvalue % (unsigned)base  ];
 492         uvalue = (uvalue / (unsigned)base );
 493     } while(uvalue && (place < 20));
 494     if (place == 20) place--;
 495     convert[place] = 0;
 496
 497     zpadlen = max - place;
 498     spadlen = min - MAX (max, place) - (signvalue ? 1 : 0);
 499     if (zpadlen < 0) zpadlen = 0;
 500     if (spadlen < 0) spadlen = 0;
 501     if (flags & DP_F_ZERO) {
 502         zpadlen = MAX(zpadlen, spadlen);
 503         spadlen = 0;
 504     }
 505     if (flags & DP_F_MINUS)
 506         spadlen = -spadlen; /* Left Justifty */
 507
 508 #ifdef DEBUG_SNPRINTF
 509     printf("zpad: %d, spad: %d, min: %d, max: %d, place: %d\n",
 510            zpadlen, spadlen, min, max, place);
 511 #endif
 512
 513     /* Spaces */
 514     while (spadlen > 0) {
 515         dopr_outch (buffer, currlen, maxlen, ' ');
 516         --spadlen;
 517     }
 518
 519     /* Sign */
 520     if (signvalue)
 521         dopr_outch (buffer, currlen, maxlen, signvalue);
 522
 523     /* Zeros */
 524     if (zpadlen > 0) {
 525         while (zpadlen > 0) {
 526             dopr_outch (buffer, currlen, maxlen, '0');
 527             --zpadlen;
 528         }
 529     }
 530
 531     /* Digits */
 532     while (place > 0)
 533         dopr_outch (buffer, currlen, maxlen, convert[--place]);
 534
 535     /* Left Justified spaces */
 536     while (spadlen < 0) {
 537         dopr_outch (buffer, currlen, maxlen, ' ');
 538         ++spadlen;
 539     }
 540 }
 541
 542 static LDOUBLE abs_val(LDOUBLE value)
 543 {
 544     LDOUBLE result = value;
 545
 546     if (value < 0)
 547         result = -value;
 548
 549     return result;
 550 }
 551
 552 static LDOUBLE POW10(int exp)
 553 {
 554     LDOUBLE result = 1;
 555
 556     while (exp) {
 557         result *= 10;
 558         exp--;
 559     }
 560
 561     return result;
 562 }
 563
 564 static LLONG ROUND(LDOUBLE value)
 565 {
 566     LLONG intpart;
 567
 568     intpart = (LLONG)value;
 569     value = value - intpart;
 570     if (value >= 0.5) intpart++;
 571
 572     return intpart;
 573 }
 574
 575 /* a replacement for modf that doesn't need the math library. Should
 576  be portable, but slow */
 577 static double my_modf(double x0, double *iptr)
 578 {
 579     int i;
 580     long l;
 581     double x = x0;
 582     double f = 1.0;
 583
 584     for (i=0;i<100;i ++) {
 585         l = (long)x;
 586         if (l <= (x+1) && l >= (x-1)) break;
 587         x *= 0.1;
 588         f *= 10.0;
 589     }
 590
 591     if (i == 100) {
 592         /* yikes! the number is beyond what we can handle. What do we do? */
 593         (*iptr) = 0;
 594         return 0;
 595     }
 596
 597     if (i != 0) {
 598         double i2;
 599         double ret;
 600
 601         ret = my_modf(x0-l*f, &i2);
 602         (*iptr) = l*f + i2;
 603         return ret;
 604     }
 605
 606     (*iptr) = l;
 607     return x - (*iptr);
 608 }
 609
 610
 611 static void fmtfp (char *buffer, size_t *currlen, size_t maxlen,
 612                    LDOUBLE fvalue, int min, int max, int flags)
 613 {
 614     int signvalue = 0;
 615     double ufvalue;
 616     char iconvert[311];
 617     char fconvert[311];
 618     int iplace = 0;
 619     int fplace = 0;
 620     int padlen = 0; /* amount to pad */
 621     int zpadlen = 0;
 622     int caps = 0;
 623     int index;
 624     double intpart;
 625     double fracpart;
 626     double temp;
 627
 628     /*
 629      * AIX manpage says the default is 0, but Solaris says the default
 630      * is 6, and sprintf on AIX defaults to 6
 631      */
 632     if (max < 0)
 633         max = 6;
 634
 635     ufvalue = abs_val (fvalue);
 636
 637     if (fvalue < 0) {
 638         signvalue = '-';
 639     } else {
 640         if (flags & DP_F_PLUS) { /* Do a sign (+/i) */
 641             signvalue = '+';
 642         } else {
 643             if (flags & DP_F_SPACE)
 644                 signvalue = ' ';
 645         }
 646     }
 647
 648 #if 0
 649     if (flags & DP_F_UP) caps = 1; /* Should characters be upper case? */
 650 #endif
 651
 652 #if 0
 653     if (max == 0) ufvalue += 0.5; /* if max = 0 we must round */
 654 #endif
 655
 656     /*
 657      * Sorry, we only support 16 digits past the decimal because of our
 658      * conversion method
 659      */
 660     if (max > 16)
 661         max = 16;
 662
 663     /* We "cheat" by converting the fractional part to integer by
 664      * multiplying by a factor of 10
 665      */
 666
 667     temp = ufvalue;
 668     my_modf(temp, &intpart);
 669
 670     fracpart = ROUND((POW10(max)) * (ufvalue - intpart));
 671
 672     if (fracpart >= POW10(max)) {
 673         intpart++;
 674         fracpart -= POW10(max);
 675     }
 676
 677
 678     /* Convert integer part */
 679     do {
 680         temp = intpart;
 681         my_modf(intpart*0.1, &intpart);
 682         temp = temp*0.1;
 683         index = (int) ((temp -intpart +0.05)* 10.0);
 684         /* index = (int) (((double)(temp*0.1) -intpart +0.05) *10.0); */
 685         /* printf ("%llf, %f, %x\n", temp, intpart, index); */
 686         iconvert[iplace++] =
 687             (caps? "0123456789ABCDEF":"0123456789abcdef")[index];
 688     } while (intpart && (iplace < 311));
 689     if (iplace == 311) iplace--;
 690     iconvert[iplace] = 0;
 691
 692     /* Convert fractional part */
 693     if (fracpart)
 694     {
 695         do {
 696             temp = fracpart;
 697             my_modf(fracpart*0.1, &fracpart);
 698             temp = temp*0.1;
 699             index = (int) ((temp -fracpart +0.05)* 10.0);
 700             /* index = (int) ((((temp/10) -fracpart) +0.05) *10); */
 701             /* printf ("%lf, %lf, %ld\n", temp, fracpart, index); */
 702             fconvert[fplace++] =
 703                 (caps? "0123456789ABCDEF":"0123456789abcdef")[index];
 704         } while(fracpart && (fplace < 311));
 705         if (fplace == 311) fplace--;
 706     }
 707     fconvert[fplace] = 0;
 708
 709     /* -1 for decimal point, another -1 if we are printing a sign */
 710     padlen = min - iplace - max - 1 - ((signvalue) ? 1 : 0);
 711     zpadlen = max - fplace;
 712     if (zpadlen < 0) zpadlen = 0;
 713     if (padlen < 0)
 714         padlen = 0;
 715     if (flags & DP_F_MINUS)
 716         padlen = -padlen; /* Left Justifty */
 717
 718     if ((flags & DP_F_ZERO) && (padlen > 0)) {
 719         if (signvalue) {
 720             dopr_outch (buffer, currlen, maxlen, signvalue);
 721             --padlen;
 722             signvalue = 0;
 723         }
 724         while (padlen > 0) {
 725             dopr_outch (buffer, currlen, maxlen, '0');
 726             --padlen;
 727         }
 728     }
 729     while (padlen > 0) {
 730         dopr_outch (buffer, currlen, maxlen, ' ');
 731         --padlen;
 732     }
 733     if (signvalue)
 734         dopr_outch (buffer, currlen, maxlen, signvalue);
 735
 736     while (iplace > 0)
 737         dopr_outch (buffer, currlen, maxlen, iconvert[--iplace]);
 738
 739 #ifdef DEBUG_SNPRINTF
 740     printf("fmtfp: fplace=%d zpadlen=%d\n", fplace, zpadlen);
 741 #endif
 742
 743     /*
 744      * Decimal point.  This should probably use locale to find the correct
 745      * char to print out.
 746      */
 747     if (max > 0) {
 748         dopr_outch (buffer, currlen, maxlen, '.');
 749
 750         while (fplace > 0)
 751             dopr_outch (buffer, currlen, maxlen, fconvert[--fplace]);
 752     }
 753
 754     while (zpadlen > 0) {
 755         dopr_outch (buffer, currlen, maxlen, '0');
 756         --zpadlen;
 757     }
 758
 759     while (padlen < 0) {
 760         dopr_outch (buffer, currlen, maxlen, ' ');
 761         ++padlen;
 762     }
 763 }
 764
 765 static void dopr_outch(char *buffer, size_t *currlen, size_t maxlen, char c)
 766 {
 767     if (*currlen < maxlen) {
 768         buffer[(*currlen)] = c;
 769     }
 770     (*currlen)++;
 771 }
 772
 773 #if !defined(HAVE_VSNPRINTF) || !defined(HAVE_C99_VSNPRINTF)
 774 int vsnprintf (char *str, size_t count, const char *fmt, va_list args)
 775 {
 776     return dopr(str, count, fmt, args);
 777 }
 778 #endif
 779
 780 #if !defined(HAVE_SNPRINTF) || !defined(HAVE_C99_VSNPRINTF)
 781 int snprintf(char *str,size_t count,const char *fmt,...)
 782 {
 783     size_t ret;
 784     va_list ap;
 785
 786     va_start(ap, fmt);
 787     ret = vsnprintf(str, count, fmt, ap);
 788     va_end(ap);
 789     return ret;
 790 }
 791 #endif
 792
 793 #endif
 794
 795 #ifndef HAVE_VASPRINTF
 796 int vasprintf(char **ptr, const char *format, va_list ap)
 797 {
 798     int ret;
 799
 800     ret = vsnprintf(NULL, 0, format, ap);
 801     if (ret <= 0) return ret;
 802
 803     (*ptr) = (char *)io_calloc(1, ret+1);
 804     if (!*ptr) return -1;
 805     ret = vsnprintf(*ptr, ret+1, format, ap);
 806
 807     return ret;
 808 }
 809 #endif
 810
 811
 812 #ifndef HAVE_ASPRINTF
 813 int asprintf(char **ptr, const char *format, ...)
 814 {
 815     va_list ap;
 816     int ret;
 817
 818     va_start(ap, format);
 819     ret = vasprintf(ptr, format, ap);
 820     va_end(ap);
 821
 822     return ret;
 823 }
 824 #endif
 825
 826 #ifdef TEST_SNPRINTF
 827
 828 int sprintf(char *str,const char *fmt,...);
 829
 830 int main (void)
 831 {
 832     char buf1[1024];
 833     char buf2[1024];
 834     char *fp_fmt[] = {
 835         "%1.1f",
 836         "%-1.5f",
 837         "%1.5f",
 838         "%123.9f",
 839         "%10.5f",
 840         "% 10.5f",
 841         "%+22.9f",
 842         "%+4.9f",
 843         "%01.3f",
 844         "%4f",
 845         "%3.1f",
 846         "%3.2f",
 847         "%.0f",
 848         "%f",
 849         "-16.16f",
 850         NULL
 851     };
 852     double fp_nums[] = { 6442452944.1234, -1.5, 134.21, 91340.2, 341.1234, 0203.9, 0.96, 0.996,
 853     0.9996, 1.996, 4.136,  0};
 854     char *int_fmt[] = {
 855         "%-1.5d",
 856         "%1.5d",
 857         "%123.9d",
 858         "%5.5d",
 859         "%10.5d",
 860         "% 10.5d",
 861         "%+22.33d",
 862         "%01.3d",
 863         "%4d",
 864         "%d",
 865         NULL
 866     };
 867     long int_nums[] = { -1, 134, 91340, 341, 0203, 0};
 868     char *str_fmt[] = {
 869         "10.5s",
 870         "5.10s",
 871         "10.1s",
 872         "0.10s",
 873         "10.0s",
 874         "1.10s",
 875         "%s",
 876         "%.1s",
 877         "%.10s",
 878         "%10s",
 879         NULL
 880     };
 881     char *str_vals[] = {"hello", "a", "", "a longer string", NULL};
 882     int x, y;
 883     int fail = 0;
 884     int num = 0;
 885
 886     printf ("Testing snprintf format codes against system sprintf...\n");
 887
 888     for (x = 0; fp_fmt[x] ; x++) {
 889         for (y = 0; fp_nums[y] != 0 ; y++) {
 890             int l1 = snprintf(NULL, 0, fp_fmt[x], fp_nums[y]);
 891             int l2 = snprintf(buf1, sizeof(buf1), fp_fmt[x], fp_nums[y]);
 892             sprintf (buf2, fp_fmt[x], fp_nums[y]);
 893             if (strcmp (buf1, buf2)) {
 894                 printf("snprintf doesn't match Format: %s\n\tsnprintf = [%s]\n\t sprintf = [%s]\n",
 895                        fp_fmt[x], buf1, buf2);
 896                 fail++;
 897             }
 898             if (l1 != l2) {
 899                 printf("snprintf l1 != l2 (%d %d) %s\n", l1, l2, fp_fmt[x]);
 900                 fail++;
 901             }
 902             num++;
 903         }
 904     }
 905
 906     for (x = 0; int_fmt[x] ; x++) {
 907         for (y = 0; int_nums[y] != 0 ; y++) {
 908             int l1 = snprintf(NULL, 0, int_fmt[x], int_nums[y]);
 909             int l2 = snprintf(buf1, sizeof(buf1), int_fmt[x], int_nums[y]);
 910             sprintf (buf2, int_fmt[x], int_nums[y]);
 911             if (strcmp (buf1, buf2)) {
 912                 printf("snprintf doesn't match Format: %s\n\tsnprintf = [%s]\n\t sprintf = [%s]\n",
 913                        int_fmt[x], buf1, buf2);
 914                 fail++;
 915             }
 916             if (l1 != l2) {
 917                 printf("snprintf l1 != l2 (%d %d) %s\n", l1, l2, int_fmt[x]);
 918                 fail++;
 919             }
 920             num++;
 921         }
 922     }
 923
 924     for (x = 0; str_fmt[x] ; x++) {
 925         for (y = 0; str_vals[y] != 0 ; y++) {
 926             int l1 = snprintf(NULL, 0, str_fmt[x], str_vals[y]);
 927             int l2 = snprintf(buf1, sizeof(buf1), str_fmt[x], str_vals[y]);
 928             sprintf (buf2, str_fmt[x], str_vals[y]);
 929             if (strcmp (buf1, buf2)) {
 930                 printf("snprintf doesn't match Format: %s\n\tsnprintf = [%s]\n\t sprintf = [%s]\n",
 931                        str_fmt[x], buf1, buf2);
 932                 fail++;
 933             }
 934             if (l1 != l2) {
 935                 printf("snprintf l1 != l2 (%d %d) %s\n", l1, l2, str_fmt[x]);
 936                 fail++;
 937             }
 938             num++;
 939         }
 940     }
 941
 942     printf ("%d tests failed out of %d.\n", fail, num);
 943
 944     printf("seeing how many digits we support\n");
 945     {
 946         double v0 = 0.12345678901234567890123456789012345678901;
 947         for (x=0; x<100; x++) {
 948             snprintf(buf1, sizeof(buf1), "%1.1f", v0*pow(10, x));
 949             sprintf(buf2,                "%1.1f", v0*pow(10, x));
 950             if (strcmp(buf1, buf2)) {
 951                 printf("we seem to support %d digits\n", x-1);
 952                 break;
 953             }
 954         }
 955     }
 956
 957     return 0;
 958 }
 959 #endif /* SNPRINTF_TEST */