openbsd-compat/bsd-snprintf.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  * date: 2002/12/19 19:56:31;  author: herb;  state: Exp;  lines: +2 -0
  57  * actually print args for %g and %e
  58  *
  59  * date: 2002/06/03 13:37:52;  author: jmcd;  state: Exp;  lines: +8 -0
  60  * Since includes.h isn't included here, VA_COPY has to be defined here.  I don't
  61  * see any include file that is guaranteed to be here, so I'm defining it
  62  * locally.  Fixes AIX and Solaris builds.
  63  *
  64  * date: 2002/06/03 03:07:24;  author: tridge;  state: Exp;  lines: +5 -13
  65  * put the ifdef for HAVE_VA_COPY in one place rather than in lots of
  66  * functions
  67  *
  68  * date: 2002/05/17 14:51:22;  author: jmcd;  state: Exp;  lines: +21 -4
  69  * Fix usage of va_list passed as an arg.  Use __va_copy before using it
  70  * when it exists.
  71  *
  72  * date: 2002/04/16 22:38:04;  author: idra;  state: Exp;  lines: +20 -14
  73  * Fix incorrect zpadlen handling in fmtfp.
  74  * Thanks to Ollie Oldham <ollie.oldham@metro-optix.com> for spotting it.
  75  * few mods to make it easier to compile the tests.
  76  * addedd the "Ollie" test to the floating point ones.
  77  *
  78  * Martin Pool (mbp@samba.org) April 2003
  79  *    Remove NO_CONFIG_H so that the test case can be built within a source
  80  *    tree with less trouble.
  81  *    Remove unnecessary SAFE_FREE() definition.
  82  *
  83  * Martin Pool (mbp@samba.org) May 2003
  84  *    Put in a prototype for dummy_snprintf() to quiet compiler warnings.
  85  *
  86  *    Move #endif to make sure VA_COPY, LDOUBLE, etc are defined even
  87  *    if the C library has some snprintf functions already.
  88  *
  89  * Damien Miller (djm@mindrot.org) Jan 2007
  90  *    Fix integer overflows in return value.
  91  *    Make formatting quite a bit faster by inlining dopr_outch()
  92  *
  93  **************************************************************/
  94
  95 #include "includes.h"
  96
  97 #if defined(BROKEN_SNPRINTF)            /* For those with broken snprintf() */
  98 # undef HAVE_SNPRINTF
  99 # undef HAVE_VSNPRINTF
 100 #endif
 101
 102 #ifndef VA_COPY
 103 # ifdef HAVE_VA_COPY
 104 #  define VA_COPY(dest, src) va_copy(dest, src)
 105 # else
 106 #  ifdef HAVE___VA_COPY
 107 #   define VA_COPY(dest, src) __va_copy(dest, src)
 108 #  else
 109 #   define VA_COPY(dest, src) (dest) = (src)
 110 #  endif
 111 # endif
 112 #endif
 113
 114 #if !defined(HAVE_SNPRINTF) || !defined(HAVE_VSNPRINTF)
 115
 116 #include <ctype.h>
 117 #include <stdarg.h>
 118 #include <stdlib.h>
 119 #include <string.h>
 120 #include <limits.h>
 121 #include <errno.h>
 122
 123 #ifdef HAVE_LONG_DOUBLE
 124 # define LDOUBLE long double
 125 #else
 126 # define LDOUBLE double
 127 #endif
 128
 129 #ifdef HAVE_LONG_LONG
 130 # define LLONG long long
 131 #else
 132 # define LLONG long
 133 #endif
 134
 135 /*
 136  * dopr(): poor man's version of doprintf
 137  */
 138
 139 /* format read states */
 140 #define DP_S_DEFAULT 0
 141 #define DP_S_FLAGS   1
 142 #define DP_S_MIN     2
 143 #define DP_S_DOT     3
 144 #define DP_S_MAX     4
 145 #define DP_S_MOD     5
 146 #define DP_S_CONV    6
 147 #define DP_S_DONE    7
 148
 149 /* format flags - Bits */
 150 #define DP_F_MINUS      (1 << 0)
 151 #define DP_F_PLUS       (1 << 1)
 152 #define DP_F_SPACE      (1 << 2)
 153 #define DP_F_NUM        (1 << 3)
 154 #define DP_F_ZERO       (1 << 4)
 155 #define DP_F_UP         (1 << 5)
 156 #define DP_F_UNSIGNED   (1 << 6)
 157
 158 /* Conversion Flags */
 159 #define DP_C_SHORT   1
 160 #define DP_C_LONG    2
 161 #define DP_C_LDOUBLE 3
 162 #define DP_C_LLONG   4
 163
 164 #define char_to_int(p) ((p)- '0')
 165 #ifndef MAX
 166 # define MAX(p,q) (((p) >= (q)) ? (p) : (q))
 167 #endif
 168
 169 #define DOPR_OUTCH(buf, pos, buflen, thechar) \
 170         do { \
 171                 if (pos + 1 >= INT_MAX) { \
 172                         errno = ERANGE; \
 173                         return -1; \
 174                 } \
 175                 if (pos < buflen) \
 176                         buf[pos] = thechar; \
 177                 (pos)++; \
 178         } while (0)
 179
 180 static int dopr(char *buffer, size_t maxlen, const char *format,
 181     va_list args_in);
 182 static int fmtstr(char *buffer, size_t *currlen, size_t maxlen,
 183     char *value, int flags, int min, int max);
 184 static int fmtint(char *buffer, size_t *currlen, size_t maxlen,
 185     LLONG value, int base, int min, int max, int flags);
 186 static int fmtfp(char *buffer, size_t *currlen, size_t maxlen,
 187     LDOUBLE fvalue, int min, int max, int flags);
 188
 189 static int
 190 dopr(char *buffer, size_t maxlen, const char *format, va_list args_in)
 191 {
 192         char ch;
 193         LLONG value;
 194         LDOUBLE fvalue;
 195         char *strvalue;
 196         int min;
 197         int max;
 198         int state;
 199         int flags;
 200         int cflags;
 201         size_t currlen;
 202         va_list args;
 203
 204         VA_COPY(args, args_in);
 205
 206         state = DP_S_DEFAULT;
 207         currlen = flags = cflags = min = 0;
 208         max = -1;
 209         ch = *format++;
 210
 211         while (state != DP_S_DONE) {
 212                 if (ch == '\0')
 213                         state = DP_S_DONE;
 214
 215                 switch(state) {
 216                 case DP_S_DEFAULT:
 217                         if (ch == '%')
 218                                 state = DP_S_FLAGS;
 219                         else
 220                                 DOPR_OUTCH(buffer, currlen, maxlen, ch);
 221                         ch = *format++;
 222                         break;
 223                 case DP_S_FLAGS:
 224                         switch (ch) {
 225                         case '-':
 226                                 flags |= DP_F_MINUS;
 227                                 ch = *format++;
 228                                 break;
 229                         case '+':
 230                                 flags |= DP_F_PLUS;
 231                                 ch = *format++;
 232                                 break;
 233                         case ' ':
 234                                 flags |= DP_F_SPACE;
 235                                 ch = *format++;
 236                                 break;
 237                         case '#':
 238                                 flags |= DP_F_NUM;
 239                                 ch = *format++;
 240                                 break;
 241                         case '0':
 242                                 flags |= DP_F_ZERO;
 243                                 ch = *format++;
 244                                 break;
 245                         default:
 246                                 state = DP_S_MIN;
 247                                 break;
 248                         }
 249                         break;
 250                 case DP_S_MIN:
 251                         if (isdigit((unsigned char)ch)) {
 252                                 min = 10*min + char_to_int (ch);
 253                                 ch = *format++;
 254                         } else if (ch == '*') {
 255                                 min = va_arg (args, int);
 256                                 ch = *format++;
 257                                 state = DP_S_DOT;
 258                         } else {
 259                                 state = DP_S_DOT;
 260                         }
 261                         break;
 262                 case DP_S_DOT:
 263                         if (ch == '.') {
 264                                 state = DP_S_MAX;
 265                                 ch = *format++;
 266                         } else {
 267                                 state = DP_S_MOD;
 268                         }
 269                         break;
 270                 case DP_S_MAX:
 271                         if (isdigit((unsigned char)ch)) {
 272                                 if (max < 0)
 273                                         max = 0;
 274                                 max = 10*max + char_to_int (ch);
 275                                 ch = *format++;
 276                         } else if (ch == '*') {
 277                                 max = va_arg (args, int);
 278                                 ch = *format++;
 279                                 state = DP_S_MOD;
 280                         } else {
 281                                 state = DP_S_MOD;
 282                         }
 283                         break;
 284                 case DP_S_MOD:
 285                         switch (ch) {
 286                         case 'h':
 287                                 cflags = DP_C_SHORT;
 288                                 ch = *format++;
 289                                 break;
 290                         case 'l':
 291                                 cflags = DP_C_LONG;
 292                                 ch = *format++;
 293                                 if (ch == 'l') {        /* It's a long long */
 294                                         cflags = DP_C_LLONG;
 295                                         ch = *format++;
 296                                 }
 297                                 break;
 298                         case 'L':
 299                                 cflags = DP_C_LDOUBLE;
 300                                 ch = *format++;
 301                                 break;
 302                         default:
 303                                 break;
 304                         }
 305                         state = DP_S_CONV;
 306                         break;
 307                 case DP_S_CONV:
 308                         switch (ch) {
 309                         case 'd':
 310                         case 'i':
 311                                 if (cflags == DP_C_SHORT)
 312                                         value = va_arg (args, int);
 313                                 else if (cflags == DP_C_LONG)
 314                                         value = va_arg (args, long int);
 315                                 else if (cflags == DP_C_LLONG)
 316                                         value = va_arg (args, LLONG);
 317                                 else
 318                                         value = va_arg (args, int);
 319                                 if (fmtint(buffer, &currlen, maxlen,
 320                                     value, 10, min, max, flags) == -1)
 321                                         return -1;
 322                                 break;
 323                         case 'o':
 324                                 flags |= DP_F_UNSIGNED;
 325                                 if (cflags == DP_C_SHORT)
 326                                         value = va_arg (args, unsigned int);
 327                                 else if (cflags == DP_C_LONG)
 328                                         value = (long)va_arg (args, unsigned long int);
 329                                 else if (cflags == DP_C_LLONG)
 330                                         value = (long)va_arg (args, unsigned LLONG);
 331                                 else
 332                                         value = (long)va_arg (args, unsigned int);
 333                                 if (fmtint(buffer, &currlen, maxlen, value,
 334                                     8, min, max, flags) == -1)
 335                                         return -1;
 336                                 break;
 337                         case 'u':
 338                                 flags |= DP_F_UNSIGNED;
 339                                 if (cflags == DP_C_SHORT)
 340                                         value = va_arg (args, unsigned int);
 341                                 else if (cflags == DP_C_LONG)
 342                                         value = (long)va_arg (args, unsigned long int);
 343                                 else if (cflags == DP_C_LLONG)
 344                                         value = (LLONG)va_arg (args, unsigned LLONG);
 345                                 else
 346                                         value = (long)va_arg (args, unsigned int);
 347                                 if (fmtint(buffer, &currlen, maxlen, value,
 348                                     10, min, max, flags) == -1)
 349                                         return -1;
 350                                 break;
 351                         case 'X':
 352                                 flags |= DP_F_UP;
 353                         case 'x':
 354                                 flags |= DP_F_UNSIGNED;
 355                                 if (cflags == DP_C_SHORT)
 356                                         value = va_arg (args, unsigned int);
 357                                 else if (cflags == DP_C_LONG)
 358                                         value = (long)va_arg (args, unsigned long int);
 359                                 else if (cflags == DP_C_LLONG)
 360                                         value = (LLONG)va_arg (args, unsigned LLONG);
 361                                 else
 362                                         value = (long)va_arg (args, unsigned int);
 363                                 if (fmtint(buffer, &currlen, maxlen, value,
 364                                     16, min, max, flags) == -1)
 365                                         return -1;
 366                                 break;
 367                         case 'f':
 368                                 if (cflags == DP_C_LDOUBLE)
 369                                         fvalue = va_arg (args, LDOUBLE);
 370                                 else
 371                                         fvalue = va_arg (args, double);
 372                                 if (fmtfp(buffer, &currlen, maxlen, fvalue,
 373                                     min, max, flags) == -1)
 374                                         return -1;
 375                                 break;
 376                         case 'E':
 377                                 flags |= DP_F_UP;
 378                         case 'e':
 379                                 if (cflags == DP_C_LDOUBLE)
 380                                         fvalue = va_arg (args, LDOUBLE);
 381                                 else
 382                                         fvalue = va_arg (args, double);
 383                                 if (fmtfp(buffer, &currlen, maxlen, fvalue,
 384                                     min, max, flags) == -1)
 385                                         return -1;
 386                                 break;
 387                         case 'G':
 388                                 flags |= DP_F_UP;
 389                         case 'g':
 390                                 if (cflags == DP_C_LDOUBLE)
 391                                         fvalue = va_arg (args, LDOUBLE);
 392                                 else
 393                                         fvalue = va_arg (args, double);
 394                                 if (fmtfp(buffer, &currlen, maxlen, fvalue,
 395                                     min, max, flags) == -1)
 396                                         return -1;
 397                                 break;
 398                         case 'c':
 399                                 DOPR_OUTCH(buffer, currlen, maxlen,
 400                                     va_arg (args, int));
 401                                 break;
 402                         case 's':
 403                                 strvalue = va_arg (args, char *);
 404                                 if (!strvalue) strvalue = "(NULL)";
 405                                 if (max == -1) {
 406                                         max = strlen(strvalue);
 407                                 }
 408                                 if (min > 0 && max >= 0 && min > max) max = min;
 409                                 if (fmtstr(buffer, &currlen, maxlen,
 410                                     strvalue, flags, min, max) == -1)
 411                                         return -1;
 412                                 break;
 413                         case 'p':
 414                                 strvalue = va_arg (args, void *);
 415                                 if (fmtint(buffer, &currlen, maxlen,
 416                                     (long) strvalue, 16, min, max, flags) == -1)
 417                                         return -1;
 418                                 break;
 419                         case 'n':
 420                                 if (cflags == DP_C_SHORT) {
 421                                         short int *num;
 422                                         num = va_arg (args, short int *);
 423                                         *num = currlen;
 424                                 } else if (cflags == DP_C_LONG) {
 425                                         long int *num;
 426                                         num = va_arg (args, long int *);
 427                                         *num = (long int)currlen;
 428                                 } else if (cflags == DP_C_LLONG) {
 429                                         LLONG *num;
 430                                         num = va_arg (args, LLONG *);
 431                                         *num = (LLONG)currlen;
 432                                 } else {
 433                                         int *num;
 434                                         num = va_arg (args, int *);
 435                                         *num = currlen;
 436                                 }
 437                                 break;
 438                         case '%':
 439                                 DOPR_OUTCH(buffer, currlen, maxlen, ch);
 440                                 break;
 441                         case 'w':
 442                                 /* not supported yet, treat as next char */
 443                                 ch = *format++;
 444                                 break;
 445                         default:
 446                                 /* Unknown, skip */
 447                                 break;
 448                         }
 449                         ch = *format++;
 450                         state = DP_S_DEFAULT;
 451                         flags = cflags = min = 0;
 452                         max = -1;
 453                         break;
 454                 case DP_S_DONE:
 455                         break;
 456                 default:
 457                         /* hmm? */
 458                         break; /* some picky compilers need this */
 459                 }
 460         }
 461         if (maxlen != 0) {
 462                 if (currlen < maxlen - 1)
 463                         buffer[currlen] = '\0';
 464                 else if (maxlen > 0)
 465                         buffer[maxlen - 1] = '\0';
 466         }
 467
 468         return currlen < INT_MAX ? (int)currlen : -1;
 469 }
 470
 471 static int
 472 fmtstr(char *buffer, size_t *currlen, size_t maxlen,
 473     char *value, int flags, int min, int max)
 474 {
 475         int padlen, strln;     /* amount to pad */
 476         int cnt = 0;
 477
 478 #ifdef DEBUG_SNPRINTF
 479         printf("fmtstr min=%d max=%d s=[%s]\n", min, max, value);
 480 #endif
 481         if (value == 0) {
 482                 value = "<NULL>";
 483         }
 484
 485         for (strln = 0; strln < max && value[strln]; ++strln); /* strlen */
 486         padlen = min - strln;
 487         if (padlen < 0)
 488                 padlen = 0;
 489         if (flags & DP_F_MINUS)
 490                 padlen = -padlen; /* Left Justify */
 491
 492         while ((padlen > 0) && (cnt < max)) {
 493                 DOPR_OUTCH(buffer, *currlen, maxlen, ' ');
 494                 --padlen;
 495                 ++cnt;
 496         }
 497         while (*value && (cnt < max)) {
 498                 DOPR_OUTCH(buffer, *currlen, maxlen, *value);
 499                 *value++;
 500                 ++cnt;
 501         }
 502         while ((padlen < 0) && (cnt < max)) {
 503                 DOPR_OUTCH(buffer, *currlen, maxlen, ' ');
 504                 ++padlen;
 505                 ++cnt;
 506         }
 507         return 0;
 508 }
 509
 510 /* Have to handle DP_F_NUM (ie 0x and 0 alternates) */
 511
 512 static int
 513 fmtint(char *buffer, size_t *currlen, size_t maxlen,
 514                     LLONG value, int base, int min, int max, int flags)
 515 {
 516         int signvalue = 0;
 517         unsigned LLONG uvalue;
 518         char convert[20];
 519         int place = 0;
 520         int spadlen = 0; /* amount to space pad */
 521         int zpadlen = 0; /* amount to zero pad */
 522         int caps = 0;
 523
 524         if (max < 0)
 525                 max = 0;
 526
 527         uvalue = value;
 528
 529         if(!(flags & DP_F_UNSIGNED)) {
 530                 if( value < 0 ) {
 531                         signvalue = '-';
 532                         uvalue = -value;
 533                 } else {
 534                         if (flags & DP_F_PLUS)  /* Do a sign (+/i) */
 535                                 signvalue = '+';
 536                         else if (flags & DP_F_SPACE)
 537                                 signvalue = ' ';
 538                 }
 539         }
 540
 541         if (flags & DP_F_UP) caps = 1; /* Should characters be upper case? */
 542
 543         do {
 544                 convert[place++] =
 545                         (caps? "0123456789ABCDEF":"0123456789abcdef")
 546                         [uvalue % (unsigned)base  ];
 547                 uvalue = (uvalue / (unsigned)base );
 548         } while(uvalue && (place < 20));
 549         if (place == 20) place--;
 550         convert[place] = 0;
 551
 552         zpadlen = max - place;
 553         spadlen = min - MAX (max, place) - (signvalue ? 1 : 0);
 554         if (zpadlen < 0) zpadlen = 0;
 555         if (spadlen < 0) spadlen = 0;
 556         if (flags & DP_F_ZERO) {
 557                 zpadlen = MAX(zpadlen, spadlen);
 558                 spadlen = 0;
 559         }
 560         if (flags & DP_F_MINUS)
 561                 spadlen = -spadlen; /* Left Justifty */
 562
 563 #ifdef DEBUG_SNPRINTF
 564         printf("zpad: %d, spad: %d, min: %d, max: %d, place: %d\n",
 565                zpadlen, spadlen, min, max, place);
 566 #endif
 567
 568         /* Spaces */
 569         while (spadlen > 0) {
 570                 DOPR_OUTCH(buffer, *currlen, maxlen, ' ');
 571                 --spadlen;
 572         }
 573
 574         /* Sign */
 575         if (signvalue)
 576                 DOPR_OUTCH(buffer, *currlen, maxlen, signvalue);
 577
 578         /* Zeros */
 579         if (zpadlen > 0) {
 580                 while (zpadlen > 0) {
 581                         DOPR_OUTCH(buffer, *currlen, maxlen, '0');
 582                         --zpadlen;
 583                 }
 584         }
 585
 586         /* Digits */
 587         while (place > 0) {
 588                 --place;
 589                 DOPR_OUTCH(buffer, *currlen, maxlen, convert[place]);
 590         }
 591
 592         /* Left Justified spaces */
 593         while (spadlen < 0) {
 594                 DOPR_OUTCH(buffer, *currlen, maxlen, ' ');
 595                 ++spadlen;
 596         }
 597         return 0;
 598 }
 599
 600 static LDOUBLE abs_val(LDOUBLE value)
 601 {
 602         LDOUBLE result = value;
 603
 604         if (value < 0)
 605                 result = -value;
 606
 607         return result;
 608 }
 609
 610 static LDOUBLE POW10(int val)
 611 {
 612         LDOUBLE result = 1;
 613
 614         while (val) {
 615                 result *= 10;
 616                 val--;
 617         }
 618
 619         return result;
 620 }
 621
 622 static LLONG ROUND(LDOUBLE value)
 623 {
 624         LLONG intpart;
 625
 626         intpart = (LLONG)value;
 627         value = value - intpart;
 628         if (value >= 0.5) intpart++;
 629
 630         return intpart;
 631 }
 632
 633 /* a replacement for modf that doesn't need the math library. Should
 634    be portable, but slow */
 635 static double my_modf(double x0, double *iptr)
 636 {
 637         int i;
 638         long l;
 639         double x = x0;
 640         double f = 1.0;
 641
 642         for (i=0;i<100;i++) {
 643                 l = (long)x;
 644                 if (l <= (x+1) && l >= (x-1)) break;
 645                 x *= 0.1;
 646                 f *= 10.0;
 647         }
 648
 649         if (i == 100) {
 650                 /*
 651                  * yikes! the number is beyond what we can handle.
 652                  * What do we do?
 653                  */
 654                 (*iptr) = 0;
 655                 return 0;
 656         }
 657
 658         if (i != 0) {
 659                 double i2;
 660                 double ret;
 661
 662                 ret = my_modf(x0-l*f, &i2);
 663                 (*iptr) = l*f + i2;
 664                 return ret;
 665         }
 666
 667         (*iptr) = l;
 668         return x - (*iptr);
 669 }
 670
 671
 672 static int
 673 fmtfp (char *buffer, size_t *currlen, size_t maxlen,
 674     LDOUBLE fvalue, int min, int max, int flags)
 675 {
 676         int signvalue = 0;
 677         double ufvalue;
 678         char iconvert[311];
 679         char fconvert[311];
 680         int iplace = 0;
 681         int fplace = 0;
 682         int padlen = 0; /* amount to pad */
 683         int zpadlen = 0;
 684         int caps = 0;
 685         int idx;
 686         double intpart;
 687         double fracpart;
 688         double temp;
 689
 690         /*
 691          * AIX manpage says the default is 0, but Solaris says the default
 692          * is 6, and sprintf on AIX defaults to 6
 693          */
 694         if (max < 0)
 695                 max = 6;
 696
 697         ufvalue = abs_val (fvalue);
 698
 699         if (fvalue < 0) {
 700                 signvalue = '-';
 701         } else {
 702                 if (flags & DP_F_PLUS) { /* Do a sign (+/i) */
 703                         signvalue = '+';
 704                 } else {
 705                         if (flags & DP_F_SPACE)
 706                                 signvalue = ' ';
 707                 }
 708         }
 709
 710 #if 0
 711         if (flags & DP_F_UP) caps = 1; /* Should characters be upper case? */
 712 #endif
 713
 714 #if 0
 715          if (max == 0) ufvalue += 0.5; /* if max = 0 we must round */
 716 #endif
 717
 718         /*
 719          * Sorry, we only support 16 digits past the decimal because of our
 720          * conversion method
 721          */
 722         if (max > 16)
 723                 max = 16;
 724
 725         /* We "cheat" by converting the fractional part to integer by
 726          * multiplying by a factor of 10
 727          */
 728
 729         temp = ufvalue;
 730         my_modf(temp, &intpart);
 731
 732         fracpart = ROUND((POW10(max)) * (ufvalue - intpart));
 733
 734         if (fracpart >= POW10(max)) {
 735                 intpart++;
 736                 fracpart -= POW10(max);
 737         }
 738
 739         /* Convert integer part */
 740         do {
 741                 temp = intpart*0.1;
 742                 my_modf(temp, &intpart);
 743                 idx = (int) ((temp -intpart +0.05)* 10.0);
 744                 /* idx = (int) (((double)(temp*0.1) -intpart +0.05) *10.0); */
 745                 /* printf ("%llf, %f, %x\n", temp, intpart, idx); */
 746                 iconvert[iplace++] =
 747                         (caps? "0123456789ABCDEF":"0123456789abcdef")[idx];
 748         } while (intpart && (iplace < 311));
 749         if (iplace == 311) iplace--;
 750         iconvert[iplace] = 0;
 751
 752         /* Convert fractional part */
 753         if (fracpart)
 754         {
 755                 do {
 756                         temp = fracpart*0.1;
 757                         my_modf(temp, &fracpart);
 758                         idx = (int) ((temp -fracpart +0.05)* 10.0);
 759                         /* idx = (int) ((((temp/10) -fracpart) +0.05) *10); */
 760                         /* printf ("%lf, %lf, %ld\n", temp, fracpart, idx ); */
 761                         fconvert[fplace++] =
 762                         (caps? "0123456789ABCDEF":"0123456789abcdef")[idx];
 763                 } while(fracpart && (fplace < 311));
 764                 if (fplace == 311) fplace--;
 765         }
 766         fconvert[fplace] = 0;
 767
 768         /* -1 for decimal point, another -1 if we are printing a sign */
 769         padlen = min - iplace - max - 1 - ((signvalue) ? 1 : 0);
 770         zpadlen = max - fplace;
 771         if (zpadlen < 0) zpadlen = 0;
 772         if (padlen < 0)
 773                 padlen = 0;
 774         if (flags & DP_F_MINUS)
 775                 padlen = -padlen; /* Left Justifty */
 776
 777         if ((flags & DP_F_ZERO) && (padlen > 0)) {
 778                 if (signvalue) {
 779                         DOPR_OUTCH(buffer, *currlen, maxlen, signvalue);
 780                         --padlen;
 781                         signvalue = 0;
 782                 }
 783                 while (padlen > 0) {
 784                         DOPR_OUTCH(buffer, *currlen, maxlen, '0');
 785                         --padlen;
 786                 }
 787         }
 788         while (padlen > 0) {
 789                 DOPR_OUTCH(buffer, *currlen, maxlen, ' ');
 790                 --padlen;
 791         }
 792         if (signvalue)
 793                 DOPR_OUTCH(buffer, *currlen, maxlen, signvalue);
 794
 795         while (iplace > 0) {
 796                 --iplace;
 797                 DOPR_OUTCH(buffer, *currlen, maxlen, iconvert[iplace]);
 798         }
 799
 800 #ifdef DEBUG_SNPRINTF
 801         printf("fmtfp: fplace=%d zpadlen=%d\n", fplace, zpadlen);
 802 #endif
 803
 804         /*
 805          * Decimal point.  This should probably use locale to find the correct
 806          * char to print out.
 807          */
 808         if (max > 0) {
 809                 DOPR_OUTCH(buffer, *currlen, maxlen, '.');
 810
 811                 while (zpadlen > 0) {
 812                         DOPR_OUTCH(buffer, *currlen, maxlen, '0');
 813                         --zpadlen;
 814                 }
 815
 816                 while (fplace > 0) {
 817                         --fplace;
 818                         DOPR_OUTCH(buffer, *currlen, maxlen, fconvert[fplace]);
 819                 }
 820         }
 821
 822         while (padlen < 0) {
 823                 DOPR_OUTCH(buffer, *currlen, maxlen, ' ');
 824                 ++padlen;
 825         }
 826         return 0;
 827 }
 828 #endif /* !defined(HAVE_SNPRINTF) || !defined(HAVE_VSNPRINTF) */
 829
 830 #if !defined(HAVE_VSNPRINTF)
 831 int
 832 vsnprintf (char *str, size_t count, const char *fmt, va_list args)
 833 {
 834         return dopr(str, count, fmt, args);
 835 }
 836 #endif
 837
 838 #if !defined(HAVE_SNPRINTF)
 839 int
 840 snprintf(char *str, size_t count, SNPRINTF_CONST char *fmt, ...)
 841 {
 842         size_t ret;
 843         va_list ap;
 844
 845         va_start(ap, fmt);
 846         ret = vsnprintf(str, count, fmt, ap);
 847         va_end(ap);
 848         return ret;
 849 }
 850 #endif