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      1 /*
      2  * Copyright (c) 2008-2016 Stefan Krah. All rights reserved.
      3  *
      4  * Redistribution and use in source and binary forms, with or without
      5  * modification, are permitted provided that the following conditions
      6  * are met:
      7  *
      8  * 1. Redistributions of source code must retain the above copyright
      9  *    notice, this list of conditions and the following disclaimer.
     10  *
     11  * 2. Redistributions in binary form must reproduce the above copyright
     12  *    notice, this list of conditions and the following disclaimer in the
     13  *    documentation and/or other materials provided with the distribution.
     14  *
     15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS" AND
     16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
     19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     25  * SUCH DAMAGE.
     26  */
     27 
     28 
     29 #include "mpdecimal.h"
     30 #include <stdio.h>
     31 #include <stdlib.h>
     32 #include <string.h>
     33 #include <ctype.h>
     34 #include <limits.h>
     35 #include <assert.h>
     36 #include <errno.h>
     37 #include <locale.h>
     38 #include "bits.h"
     39 #include "constants.h"
     40 #include "typearith.h"
     41 #include "io.h"
     42 
     43 
     44 /* This file contains functions for decimal <-> string conversions, including
     45    PEP-3101 formatting for numeric types. */
     46 
     47 
     48 /*
     49  * Work around the behavior of tolower() and strcasecmp() in certain
     50  * locales. For example, in tr_TR.utf8:
     51  *
     52  * tolower((unsigned char)'I') == 'I'
     53  *
     54  * u is the exact uppercase version of l; n is strlen(l) or strlen(l)+1
     55  */
     56 static inline int
     57 _mpd_strneq(const char *s, const char *l, const char *u, size_t n)
     58 {
     59     while (--n != SIZE_MAX) {
     60         if (*s != *l && *s != *u) {
     61             return 0;
     62         }
     63         s++; u++; l++;
     64     }
     65 
     66     return 1;
     67 }
     68 
     69 static mpd_ssize_t
     70 strtoexp(const char *s)
     71 {
     72     char *end;
     73     mpd_ssize_t retval;
     74 
     75     errno = 0;
     76     retval = mpd_strtossize(s, &end, 10);
     77     if (errno == 0 && !(*s != '\0' && *end == '\0'))
     78         errno = EINVAL;
     79 
     80     return retval;
     81 }
     82 
     83 /*
     84  * Scan 'len' words. The most significant word contains 'r' digits,
     85  * the remaining words are full words. Skip dpoint. The string 's' must
     86  * consist of digits and an optional single decimal point at 'dpoint'.
     87  */
     88 static void
     89 string_to_coeff(mpd_uint_t *data, const char *s, const char *dpoint, int r,
     90                 size_t len)
     91 {
     92     int j;
     93 
     94     if (r > 0) {
     95         data[--len] = 0;
     96         for (j = 0; j < r; j++, s++) {
     97             if (s == dpoint) s++;
     98             data[len] = 10 * data[len] + (*s - '0');
     99         }
    100     }
    101 
    102     while (--len != SIZE_MAX) {
    103         data[len] = 0;
    104         for (j = 0; j < MPD_RDIGITS; j++, s++) {
    105             if (s == dpoint) s++;
    106             data[len] = 10 * data[len] + (*s - '0');
    107         }
    108     }
    109 }
    110 
    111 /*
    112  * Partially verify a numeric string of the form:
    113  *
    114  *     [cdigits][.][cdigits][eE][+-][edigits]
    115  *
    116  * If successful, return a pointer to the location of the first
    117  * relevant coefficient digit. This digit is either non-zero or
    118  * part of one of the following patterns:
    119  *
    120  *     ["0\x00", "0.\x00", "0.E", "0.e", "0E", "0e"]
    121  *
    122  * The locations of a single optional dot or indicator are stored
    123  * in 'dpoint' and 'exp'.
    124  *
    125  * The end of the string is stored in 'end'. If an indicator [eE]
    126  * occurs without trailing [edigits], the condition is caught
    127  * later by strtoexp().
    128  */
    129 static const char *
    130 scan_dpoint_exp(const char *s, const char **dpoint, const char **exp,
    131                 const char **end)
    132 {
    133     const char *coeff = NULL;
    134 
    135     *dpoint = NULL;
    136     *exp = NULL;
    137     for (; *s != '\0'; s++) {
    138         switch (*s) {
    139         case '.':
    140             if (*dpoint != NULL || *exp != NULL)
    141                 return NULL;
    142             *dpoint = s;
    143             break;
    144         case 'E': case 'e':
    145             if (*exp != NULL)
    146                 return NULL;
    147             *exp = s;
    148             if (*(s+1) == '+' || *(s+1) == '-')
    149                 s++;
    150             break;
    151         default:
    152             if (!isdigit((uchar)*s))
    153                 return NULL;
    154             if (coeff == NULL && *exp == NULL) {
    155                 if (*s == '0') {
    156                     if (!isdigit((uchar)*(s+1)))
    157                         if (!(*(s+1) == '.' &&
    158                               isdigit((uchar)*(s+2))))
    159                             coeff = s;
    160                 }
    161                 else {
    162                     coeff = s;
    163                 }
    164             }
    165             break;
    166 
    167         }
    168     }
    169 
    170     *end = s;
    171     return coeff;
    172 }
    173 
    174 /* scan the payload of a NaN */
    175 static const char *
    176 scan_payload(const char *s, const char **end)
    177 {
    178     const char *coeff;
    179 
    180     while (*s == '0')
    181         s++;
    182     coeff = s;
    183 
    184     while (isdigit((uchar)*s))
    185         s++;
    186     *end = s;
    187 
    188     return (*s == '\0') ? coeff : NULL;
    189 }
    190 
    191 /* convert a character string to a decimal */
    192 void
    193 mpd_qset_string(mpd_t *dec, const char *s, const mpd_context_t *ctx,
    194                 uint32_t *status)
    195 {
    196     mpd_ssize_t q, r, len;
    197     const char *coeff, *end;
    198     const char *dpoint = NULL, *exp = NULL;
    199     size_t digits;
    200     uint8_t sign = MPD_POS;
    201 
    202     mpd_set_flags(dec, 0);
    203     dec->len = 0;
    204     dec->exp = 0;
    205 
    206     /* sign */
    207     if (*s == '+') {
    208         s++;
    209     }
    210     else if (*s == '-') {
    211         mpd_set_negative(dec);
    212         sign = MPD_NEG;
    213         s++;
    214     }
    215 
    216     if (_mpd_strneq(s, "nan", "NAN", 3)) { /* NaN */
    217         s += 3;
    218         mpd_setspecial(dec, sign, MPD_NAN);
    219         if (*s == '\0')
    220             return;
    221         /* validate payload: digits only */
    222         if ((coeff = scan_payload(s, &end)) == NULL)
    223             goto conversion_error;
    224         /* payload consists entirely of zeros */
    225         if (*coeff == '\0')
    226             return;
    227         digits = end - coeff;
    228         /* prec >= 1, clamp is 0 or 1 */
    229         if (digits > (size_t)(ctx->prec-ctx->clamp))
    230             goto conversion_error;
    231     } /* sNaN */
    232     else if (_mpd_strneq(s, "snan", "SNAN", 4)) {
    233         s += 4;
    234         mpd_setspecial(dec, sign, MPD_SNAN);
    235         if (*s == '\0')
    236             return;
    237         /* validate payload: digits only */
    238         if ((coeff = scan_payload(s, &end)) == NULL)
    239             goto conversion_error;
    240         /* payload consists entirely of zeros */
    241         if (*coeff == '\0')
    242             return;
    243         digits = end - coeff;
    244         if (digits > (size_t)(ctx->prec-ctx->clamp))
    245             goto conversion_error;
    246     }
    247     else if (_mpd_strneq(s, "inf", "INF", 3)) {
    248         s += 3;
    249         if (*s == '\0' || _mpd_strneq(s, "inity", "INITY", 6)) {
    250             /* numeric-value: infinity */
    251             mpd_setspecial(dec, sign, MPD_INF);
    252             return;
    253         }
    254         goto conversion_error;
    255     }
    256     else {
    257         /* scan for start of coefficient, decimal point, indicator, end */
    258         if ((coeff = scan_dpoint_exp(s, &dpoint, &exp, &end)) == NULL)
    259             goto conversion_error;
    260 
    261         /* numeric-value: [exponent-part] */
    262         if (exp) {
    263             /* exponent-part */
    264             end = exp; exp++;
    265             dec->exp = strtoexp(exp);
    266             if (errno) {
    267                 if (!(errno == ERANGE &&
    268                      (dec->exp == MPD_SSIZE_MAX ||
    269                       dec->exp == MPD_SSIZE_MIN)))
    270                     goto conversion_error;
    271             }
    272         }
    273 
    274             digits = end - coeff;
    275         if (dpoint) {
    276             size_t fracdigits = end-dpoint-1;
    277             if (dpoint > coeff) digits--;
    278 
    279             if (fracdigits > MPD_MAX_PREC) {
    280                 goto conversion_error;
    281             }
    282             if (dec->exp < MPD_SSIZE_MIN+(mpd_ssize_t)fracdigits) {
    283                 dec->exp = MPD_SSIZE_MIN;
    284             }
    285             else {
    286                 dec->exp -= (mpd_ssize_t)fracdigits;
    287             }
    288         }
    289         if (digits > MPD_MAX_PREC) {
    290             goto conversion_error;
    291         }
    292         if (dec->exp > MPD_EXP_INF) {
    293             dec->exp = MPD_EXP_INF;
    294         }
    295         if (dec->exp == MPD_SSIZE_MIN) {
    296             dec->exp = MPD_SSIZE_MIN+1;
    297         }
    298     }
    299 
    300     _mpd_idiv_word(&q, &r, (mpd_ssize_t)digits, MPD_RDIGITS);
    301 
    302     len = (r == 0) ? q : q+1;
    303     if (len == 0) {
    304         goto conversion_error; /* GCOV_NOT_REACHED */
    305     }
    306     if (!mpd_qresize(dec, len, status)) {
    307         mpd_seterror(dec, MPD_Malloc_error, status);
    308         return;
    309     }
    310     dec->len = len;
    311 
    312     string_to_coeff(dec->data, coeff, dpoint, (int)r, len);
    313 
    314     mpd_setdigits(dec);
    315     mpd_qfinalize(dec, ctx, status);
    316     return;
    317 
    318 conversion_error:
    319     /* standard wants a positive NaN */
    320     mpd_seterror(dec, MPD_Conversion_syntax, status);
    321 }
    322 
    323 /* Print word x with n decimal digits to string s. dot is either NULL
    324    or the location of a decimal point. */
    325 #define EXTRACT_DIGIT(s, x, d, dot) \
    326         if (s == dot) *s++ = '.'; *s++ = '0' + (char)(x / d); x %= d
    327 static inline char *
    328 word_to_string(char *s, mpd_uint_t x, int n, char *dot)
    329 {
    330     switch(n) {
    331 #ifdef CONFIG_64
    332     case 20: EXTRACT_DIGIT(s, x, 10000000000000000000ULL, dot); /* GCOV_NOT_REACHED */
    333     case 19: EXTRACT_DIGIT(s, x, 1000000000000000000ULL, dot);
    334     case 18: EXTRACT_DIGIT(s, x, 100000000000000000ULL, dot);
    335     case 17: EXTRACT_DIGIT(s, x, 10000000000000000ULL, dot);
    336     case 16: EXTRACT_DIGIT(s, x, 1000000000000000ULL, dot);
    337     case 15: EXTRACT_DIGIT(s, x, 100000000000000ULL, dot);
    338     case 14: EXTRACT_DIGIT(s, x, 10000000000000ULL, dot);
    339     case 13: EXTRACT_DIGIT(s, x, 1000000000000ULL, dot);
    340     case 12: EXTRACT_DIGIT(s, x, 100000000000ULL, dot);
    341     case 11: EXTRACT_DIGIT(s, x, 10000000000ULL, dot);
    342 #endif
    343     case 10: EXTRACT_DIGIT(s, x, 1000000000UL, dot);
    344     case 9:  EXTRACT_DIGIT(s, x, 100000000UL, dot);
    345     case 8:  EXTRACT_DIGIT(s, x, 10000000UL, dot);
    346     case 7:  EXTRACT_DIGIT(s, x, 1000000UL, dot);
    347     case 6:  EXTRACT_DIGIT(s, x, 100000UL, dot);
    348     case 5:  EXTRACT_DIGIT(s, x, 10000UL, dot);
    349     case 4:  EXTRACT_DIGIT(s, x, 1000UL, dot);
    350     case 3:  EXTRACT_DIGIT(s, x, 100UL, dot);
    351     case 2:  EXTRACT_DIGIT(s, x, 10UL, dot);
    352     default: if (s == dot) *s++ = '.'; *s++ = '0' + (char)x;
    353     }
    354 
    355     *s = '\0';
    356     return s;
    357 }
    358 
    359 /* Print exponent x to string s. Undefined for MPD_SSIZE_MIN. */
    360 static inline char *
    361 exp_to_string(char *s, mpd_ssize_t x)
    362 {
    363     char sign = '+';
    364 
    365     if (x < 0) {
    366         sign = '-';
    367         x = -x;
    368     }
    369     *s++ = sign;
    370 
    371     return word_to_string(s, x, mpd_word_digits(x), NULL);
    372 }
    373 
    374 /* Print the coefficient of dec to string s. len(dec) > 0. */
    375 static inline char *
    376 coeff_to_string(char *s, const mpd_t *dec)
    377 {
    378     mpd_uint_t x;
    379     mpd_ssize_t i;
    380 
    381     /* most significant word */
    382     x = mpd_msword(dec);
    383     s = word_to_string(s, x, mpd_word_digits(x), NULL);
    384 
    385     /* remaining full words */
    386     for (i=dec->len-2; i >= 0; --i) {
    387         x = dec->data[i];
    388         s = word_to_string(s, x, MPD_RDIGITS, NULL);
    389     }
    390 
    391     return s;
    392 }
    393 
    394 /* Print the coefficient of dec to string s. len(dec) > 0. dot is either
    395    NULL or a pointer to the location of a decimal point. */
    396 static inline char *
    397 coeff_to_string_dot(char *s, char *dot, const mpd_t *dec)
    398 {
    399     mpd_uint_t x;
    400     mpd_ssize_t i;
    401 
    402     /* most significant word */
    403     x = mpd_msword(dec);
    404     s = word_to_string(s, x, mpd_word_digits(x), dot);
    405 
    406     /* remaining full words */
    407     for (i=dec->len-2; i >= 0; --i) {
    408         x = dec->data[i];
    409         s = word_to_string(s, x, MPD_RDIGITS, dot);
    410     }
    411 
    412     return s;
    413 }
    414 
    415 /* Format type */
    416 #define MPD_FMT_LOWER      0x00000000
    417 #define MPD_FMT_UPPER      0x00000001
    418 #define MPD_FMT_TOSCI      0x00000002
    419 #define MPD_FMT_TOENG      0x00000004
    420 #define MPD_FMT_EXP        0x00000008
    421 #define MPD_FMT_FIXED      0x00000010
    422 #define MPD_FMT_PERCENT    0x00000020
    423 #define MPD_FMT_SIGN_SPACE 0x00000040
    424 #define MPD_FMT_SIGN_PLUS  0x00000080
    425 
    426 /* Default place of the decimal point for MPD_FMT_TOSCI, MPD_FMT_EXP */
    427 #define MPD_DEFAULT_DOTPLACE 1
    428 
    429 /*
    430  * Set *result to the string representation of a decimal. Return the length
    431  * of *result, not including the terminating '\0' character.
    432  *
    433  * Formatting is done according to 'flags'. A return value of -1 with *result
    434  * set to NULL indicates MPD_Malloc_error.
    435  *
    436  * 'dplace' is the default place of the decimal point. It is always set to
    437  * MPD_DEFAULT_DOTPLACE except for zeros in combination with MPD_FMT_EXP.
    438  */
    439 static mpd_ssize_t
    440 _mpd_to_string(char **result, const mpd_t *dec, int flags, mpd_ssize_t dplace)
    441 {
    442     char *decstring = NULL, *cp = NULL;
    443     mpd_ssize_t ldigits;
    444     mpd_ssize_t mem = 0, k;
    445 
    446     if (mpd_isspecial(dec)) {
    447 
    448         mem = sizeof "-Infinity%";
    449         if (mpd_isnan(dec) && dec->len > 0) {
    450             /* diagnostic code */
    451             mem += dec->digits;
    452         }
    453         cp = decstring = mpd_alloc(mem, sizeof *decstring);
    454         if (cp == NULL) {
    455             *result = NULL;
    456             return -1;
    457         }
    458 
    459         if (mpd_isnegative(dec)) {
    460             *cp++ = '-';
    461         }
    462         else if (flags&MPD_FMT_SIGN_SPACE) {
    463             *cp++ = ' ';
    464         }
    465         else if (flags&MPD_FMT_SIGN_PLUS) {
    466             *cp++ = '+';
    467         }
    468 
    469         if (mpd_isnan(dec)) {
    470             if (mpd_isqnan(dec)) {
    471                 strcpy(cp, "NaN");
    472                 cp += 3;
    473             }
    474             else {
    475                 strcpy(cp, "sNaN");
    476                 cp += 4;
    477             }
    478             if (dec->len > 0) { /* diagnostic code */
    479                 cp = coeff_to_string(cp, dec);
    480             }
    481         }
    482         else if (mpd_isinfinite(dec)) {
    483             strcpy(cp, "Infinity");
    484             cp += 8;
    485         }
    486         else { /* debug */
    487             abort(); /* GCOV_NOT_REACHED */
    488         }
    489     }
    490     else {
    491         assert(dec->len > 0);
    492 
    493         /*
    494          * For easier manipulation of the decimal point's location
    495          * and the exponent that is finally printed, the number is
    496          * rescaled to a virtual representation with exp = 0. Here
    497          * ldigits denotes the number of decimal digits to the left
    498          * of the decimal point and remains constant once initialized.
    499          *
    500          * dplace is the location of the decimal point relative to
    501          * the start of the coefficient. Note that 3) always holds
    502          * when dplace is shifted.
    503          *
    504          *   1) ldigits := dec->digits - dec->exp
    505          *   2) dplace  := ldigits            (initially)
    506          *   3) exp     := ldigits - dplace   (initially exp = 0)
    507          *
    508          *   0.00000_.____._____000000.
    509          *    ^      ^    ^           ^
    510          *    |      |    |           |
    511          *    |      |    |           `- dplace >= digits
    512          *    |      |    `- dplace in the middle of the coefficient
    513          *    |      ` dplace = 1 (after the first coefficient digit)
    514          *    `- dplace <= 0
    515          */
    516 
    517         ldigits = dec->digits + dec->exp;
    518 
    519         if (flags&MPD_FMT_EXP) {
    520             ;
    521         }
    522         else if (flags&MPD_FMT_FIXED || (dec->exp <= 0 && ldigits > -6)) {
    523             /* MPD_FMT_FIXED: always use fixed point notation.
    524              * MPD_FMT_TOSCI, MPD_FMT_TOENG: for a certain range,
    525              * override exponent notation. */
    526             dplace = ldigits;
    527         }
    528         else if (flags&MPD_FMT_TOENG) {
    529             if (mpd_iszero(dec)) {
    530                 /* If the exponent is divisible by three,
    531                  * dplace = 1. Otherwise, move dplace one
    532                  * or two places to the left. */
    533                 dplace = -1 + mod_mpd_ssize_t(dec->exp+2, 3);
    534             }
    535             else { /* ldigits-1 is the adjusted exponent, which
    536                 * should be divisible by three. If not, move
    537                 * dplace one or two places to the right. */
    538                 dplace += mod_mpd_ssize_t(ldigits-1, 3);
    539             }
    540         }
    541 
    542         /*
    543          * Basic space requirements:
    544          *
    545          * [-][.][coeffdigits][E][-][expdigits+1][%]['\0']
    546          *
    547          * If the decimal point lies outside of the coefficient digits,
    548          * space is adjusted accordingly.
    549          */
    550         if (dplace <= 0) {
    551             mem = -dplace + dec->digits + 2;
    552         }
    553         else if (dplace >= dec->digits) {
    554             mem = dplace;
    555         }
    556         else {
    557             mem = dec->digits;
    558         }
    559         mem += (MPD_EXPDIGITS+1+6);
    560 
    561         cp = decstring = mpd_alloc(mem, sizeof *decstring);
    562         if (cp == NULL) {
    563             *result = NULL;
    564             return -1;
    565         }
    566 
    567 
    568         if (mpd_isnegative(dec)) {
    569             *cp++ = '-';
    570         }
    571         else if (flags&MPD_FMT_SIGN_SPACE) {
    572             *cp++ = ' ';
    573         }
    574         else if (flags&MPD_FMT_SIGN_PLUS) {
    575             *cp++ = '+';
    576         }
    577 
    578         if (dplace <= 0) {
    579             /* space: -dplace+dec->digits+2 */
    580             *cp++ = '0';
    581             *cp++ = '.';
    582             for (k = 0; k < -dplace; k++) {
    583                 *cp++ = '0';
    584             }
    585             cp = coeff_to_string(cp, dec);
    586         }
    587         else if (dplace >= dec->digits) {
    588             /* space: dplace */
    589             cp = coeff_to_string(cp, dec);
    590             for (k = 0; k < dplace-dec->digits; k++) {
    591                 *cp++ = '0';
    592             }
    593         }
    594         else {
    595             /* space: dec->digits+1 */
    596             cp = coeff_to_string_dot(cp, cp+dplace, dec);
    597         }
    598 
    599         /*
    600          * Conditions for printing an exponent:
    601          *
    602          *   MPD_FMT_TOSCI, MPD_FMT_TOENG: only if ldigits != dplace
    603          *   MPD_FMT_FIXED:                never (ldigits == dplace)
    604          *   MPD_FMT_EXP:                  always
    605          */
    606         if (ldigits != dplace || flags&MPD_FMT_EXP) {
    607             /* space: expdigits+2 */
    608             *cp++ = (flags&MPD_FMT_UPPER) ? 'E' : 'e';
    609             cp = exp_to_string(cp, ldigits-dplace);
    610         }
    611     }
    612 
    613     if (flags&MPD_FMT_PERCENT) {
    614         *cp++ = '%';
    615     }
    616 
    617     assert(cp < decstring+mem);
    618     assert(cp-decstring < MPD_SSIZE_MAX);
    619 
    620     *cp = '\0';
    621     *result = decstring;
    622     return (mpd_ssize_t)(cp-decstring);
    623 }
    624 
    625 char *
    626 mpd_to_sci(const mpd_t *dec, int fmt)
    627 {
    628     char *res;
    629     int flags = MPD_FMT_TOSCI;
    630 
    631     flags |= fmt ? MPD_FMT_UPPER : MPD_FMT_LOWER;
    632     (void)_mpd_to_string(&res, dec, flags, MPD_DEFAULT_DOTPLACE);
    633     return res;
    634 }
    635 
    636 char *
    637 mpd_to_eng(const mpd_t *dec, int fmt)
    638 {
    639     char *res;
    640     int flags = MPD_FMT_TOENG;
    641 
    642     flags |= fmt ? MPD_FMT_UPPER : MPD_FMT_LOWER;
    643     (void)_mpd_to_string(&res, dec, flags, MPD_DEFAULT_DOTPLACE);
    644     return res;
    645 }
    646 
    647 mpd_ssize_t
    648 mpd_to_sci_size(char **res, const mpd_t *dec, int fmt)
    649 {
    650     int flags = MPD_FMT_TOSCI;
    651 
    652     flags |= fmt ? MPD_FMT_UPPER : MPD_FMT_LOWER;
    653     return _mpd_to_string(res, dec, flags, MPD_DEFAULT_DOTPLACE);
    654 }
    655 
    656 mpd_ssize_t
    657 mpd_to_eng_size(char **res, const mpd_t *dec, int fmt)
    658 {
    659     int flags = MPD_FMT_TOENG;
    660 
    661     flags |= fmt ? MPD_FMT_UPPER : MPD_FMT_LOWER;
    662     return _mpd_to_string(res, dec, flags, MPD_DEFAULT_DOTPLACE);
    663 }
    664 
    665 /* Copy a single UTF-8 char to dest. See: The Unicode Standard, version 5.2,
    666    chapter 3.9: Well-formed UTF-8 byte sequences. */
    667 static int
    668 _mpd_copy_utf8(char dest[5], const char *s)
    669 {
    670     const uchar *cp = (const uchar *)s;
    671     uchar lb, ub;
    672     int count, i;
    673 
    674 
    675     if (*cp == 0) {
    676         /* empty string */
    677         dest[0] = '\0';
    678         return 0;
    679     }
    680     else if (*cp <= 0x7f) {
    681         /* ascii */
    682         dest[0] = *cp;
    683         dest[1] = '\0';
    684         return 1;
    685     }
    686     else if (0xc2 <= *cp && *cp <= 0xdf) {
    687         lb = 0x80; ub = 0xbf;
    688         count = 2;
    689     }
    690     else if (*cp == 0xe0) {
    691         lb = 0xa0; ub = 0xbf;
    692         count = 3;
    693     }
    694     else if (*cp <= 0xec) {
    695         lb = 0x80; ub = 0xbf;
    696         count = 3;
    697     }
    698     else if (*cp == 0xed) {
    699         lb = 0x80; ub = 0x9f;
    700         count = 3;
    701     }
    702     else if (*cp <= 0xef) {
    703         lb = 0x80; ub = 0xbf;
    704         count = 3;
    705     }
    706     else if (*cp == 0xf0) {
    707         lb = 0x90; ub = 0xbf;
    708         count = 4;
    709     }
    710     else if (*cp <= 0xf3) {
    711         lb = 0x80; ub = 0xbf;
    712         count = 4;
    713     }
    714     else if (*cp == 0xf4) {
    715         lb = 0x80; ub = 0x8f;
    716         count = 4;
    717     }
    718     else {
    719         /* invalid */
    720         goto error;
    721     }
    722 
    723     dest[0] = *cp++;
    724     if (*cp < lb || ub < *cp) {
    725         goto error;
    726     }
    727     dest[1] = *cp++;
    728     for (i = 2; i < count; i++) {
    729         if (*cp < 0x80 || 0xbf < *cp) {
    730             goto error;
    731         }
    732         dest[i] = *cp++;
    733     }
    734     dest[i] = '\0';
    735 
    736     return count;
    737 
    738 error:
    739     dest[0] = '\0';
    740     return -1;
    741 }
    742 
    743 int
    744 mpd_validate_lconv(mpd_spec_t *spec)
    745 {
    746     size_t n;
    747 #if CHAR_MAX == SCHAR_MAX
    748     const char *cp = spec->grouping;
    749     while (*cp != '\0') {
    750         if (*cp++ < 0) {
    751             return -1;
    752         }
    753     }
    754 #endif
    755     n = strlen(spec->dot);
    756     if (n == 0 || n > 4) {
    757         return -1;
    758     }
    759     if (strlen(spec->sep) > 4) {
    760         return -1;
    761     }
    762 
    763     return 0;
    764 }
    765 
    766 int
    767 mpd_parse_fmt_str(mpd_spec_t *spec, const char *fmt, int caps)
    768 {
    769     char *cp = (char *)fmt;
    770     int have_align = 0, n;
    771 
    772     /* defaults */
    773     spec->min_width = 0;
    774     spec->prec = -1;
    775     spec->type = caps ? 'G' : 'g';
    776     spec->align = '>';
    777     spec->sign = '-';
    778     spec->dot = "";
    779     spec->sep = "";
    780     spec->grouping = "";
    781 
    782 
    783     /* presume that the first character is a UTF-8 fill character */
    784     if ((n = _mpd_copy_utf8(spec->fill, cp)) < 0) {
    785         return 0;
    786     }
    787 
    788     /* alignment directive, prefixed by a fill character */
    789     if (*cp && (*(cp+n) == '<' || *(cp+n) == '>' ||
    790                 *(cp+n) == '=' || *(cp+n) == '^')) {
    791         cp += n;
    792         spec->align = *cp++;
    793         have_align = 1;
    794     } /* alignment directive */
    795     else {
    796         /* default fill character */
    797         spec->fill[0] = ' ';
    798         spec->fill[1] = '\0';
    799         if (*cp == '<' || *cp == '>' ||
    800             *cp == '=' || *cp == '^') {
    801             spec->align = *cp++;
    802             have_align = 1;
    803         }
    804     }
    805 
    806     /* sign formatting */
    807     if (*cp == '+' || *cp == '-' || *cp == ' ') {
    808         spec->sign = *cp++;
    809     }
    810 
    811     /* zero padding */
    812     if (*cp == '0') {
    813         /* zero padding implies alignment, which should not be
    814          * specified twice. */
    815         if (have_align) {
    816             return 0;
    817         }
    818         spec->align = 'z';
    819         spec->fill[0] = *cp++;
    820         spec->fill[1] = '\0';
    821     }
    822 
    823     /* minimum width */
    824     if (isdigit((uchar)*cp)) {
    825         if (*cp == '0') {
    826             return 0;
    827         }
    828         errno = 0;
    829         spec->min_width = mpd_strtossize(cp, &cp, 10);
    830         if (errno == ERANGE || errno == EINVAL) {
    831             return 0;
    832         }
    833     }
    834 
    835     /* thousands separator */
    836     if (*cp == ',') {
    837         spec->dot = ".";
    838         spec->sep = ",";
    839         spec->grouping = "\003\003";
    840         cp++;
    841     }
    842 
    843     /* fraction digits or significant digits */
    844     if (*cp == '.') {
    845         cp++;
    846         if (!isdigit((uchar)*cp)) {
    847             return 0;
    848         }
    849         errno = 0;
    850         spec->prec = mpd_strtossize(cp, &cp, 10);
    851         if (errno == ERANGE || errno == EINVAL) {
    852             return 0;
    853         }
    854     }
    855 
    856     /* type */
    857     if (*cp == 'E' || *cp == 'e' || *cp == 'F' || *cp == 'f' ||
    858         *cp == 'G' || *cp == 'g' || *cp == '%') {
    859         spec->type = *cp++;
    860     }
    861     else if (*cp == 'N' || *cp == 'n') {
    862         /* locale specific conversion */
    863         struct lconv *lc;
    864         /* separator has already been specified */
    865         if (*spec->sep) {
    866             return 0;
    867         }
    868         spec->type = *cp++;
    869         spec->type = (spec->type == 'N') ? 'G' : 'g';
    870         lc = localeconv();
    871         spec->dot = lc->decimal_point;
    872         spec->sep = lc->thousands_sep;
    873         spec->grouping = lc->grouping;
    874         if (mpd_validate_lconv(spec) < 0) {
    875             return 0; /* GCOV_NOT_REACHED */
    876         }
    877     }
    878 
    879     /* check correctness */
    880     if (*cp != '\0') {
    881         return 0;
    882     }
    883 
    884     return 1;
    885 }
    886 
    887 /*
    888  * The following functions assume that spec->min_width <= MPD_MAX_PREC, which
    889  * is made sure in mpd_qformat_spec. Then, even with a spec that inserts a
    890  * four-byte separator after each digit, nbytes in the following struct
    891  * cannot overflow.
    892  */
    893 
    894 /* Multibyte string */
    895 typedef struct {
    896     mpd_ssize_t nbytes; /* length in bytes */
    897     mpd_ssize_t nchars; /* length in chars */
    898     mpd_ssize_t cur;    /* current write index */
    899     char *data;
    900 } mpd_mbstr_t;
    901 
    902 static inline void
    903 _mpd_bcopy(char *dest, const char *src, mpd_ssize_t n)
    904 {
    905     while (--n >= 0) {
    906         dest[n] = src[n];
    907     }
    908 }
    909 
    910 static inline void
    911 _mbstr_copy_char(mpd_mbstr_t *dest, const char *src, mpd_ssize_t n)
    912 {
    913     dest->nbytes += n;
    914     dest->nchars += (n > 0 ? 1 : 0);
    915     dest->cur -= n;
    916 
    917     if (dest->data != NULL) {
    918         _mpd_bcopy(dest->data+dest->cur, src, n);
    919     }
    920 }
    921 
    922 static inline void
    923 _mbstr_copy_ascii(mpd_mbstr_t *dest, const char *src, mpd_ssize_t n)
    924 {
    925     dest->nbytes += n;
    926     dest->nchars += n;
    927     dest->cur -= n;
    928 
    929     if (dest->data != NULL) {
    930         _mpd_bcopy(dest->data+dest->cur, src, n);
    931     }
    932 }
    933 
    934 static inline void
    935 _mbstr_copy_pad(mpd_mbstr_t *dest, mpd_ssize_t n)
    936 {
    937     dest->nbytes += n;
    938     dest->nchars += n;
    939     dest->cur -= n;
    940 
    941     if (dest->data != NULL) {
    942         char *cp = dest->data + dest->cur;
    943         while (--n >= 0) {
    944             cp[n] = '0';
    945         }
    946     }
    947 }
    948 
    949 /*
    950  * Copy a numeric string to dest->data, adding separators in the integer
    951  * part according to spec->grouping. If leading zero padding is enabled
    952  * and the result is smaller than spec->min_width, continue adding zeros
    953  * and separators until the minimum width is reached.
    954  *
    955  * The final length of dest->data is stored in dest->nbytes. The number
    956  * of UTF-8 characters is stored in dest->nchars.
    957  *
    958  * First run (dest->data == NULL): determine the length of the result
    959  * string and store it in dest->nbytes.
    960  *
    961  * Second run (write to dest->data): data is written in chunks and in
    962  * reverse order, starting with the rest of the numeric string.
    963  */
    964 static void
    965 _mpd_add_sep_dot(mpd_mbstr_t *dest,
    966                  const char *sign, /* location of optional sign */
    967                  const char *src, mpd_ssize_t n_src, /* integer part and length */
    968                  const char *dot, /* location of optional decimal point */
    969                  const char *rest, mpd_ssize_t n_rest, /* remaining part and length */
    970                  const mpd_spec_t *spec)
    971 {
    972     mpd_ssize_t n_sep, n_sign, consume;
    973     const char *g;
    974     int pad = 0;
    975 
    976     n_sign = sign ? 1 : 0;
    977     n_sep = (mpd_ssize_t)strlen(spec->sep);
    978     /* Initial write index: set to location of '\0' in the output string.
    979      * Irrelevant for the first run. */
    980     dest->cur = dest->nbytes;
    981     dest->nbytes = dest->nchars = 0;
    982 
    983     _mbstr_copy_ascii(dest, rest, n_rest);
    984 
    985     if (dot) {
    986         _mbstr_copy_char(dest, dot, (mpd_ssize_t)strlen(dot));
    987     }
    988 
    989     g = spec->grouping;
    990     consume = *g;
    991     while (1) {
    992         /* If the group length is 0 or CHAR_MAX or greater than the
    993          * number of source bytes, consume all remaining bytes. */
    994         if (*g == 0 || *g == CHAR_MAX || consume > n_src) {
    995             consume = n_src;
    996         }
    997         n_src -= consume;
    998         if (pad) {
    999             _mbstr_copy_pad(dest, consume);
   1000         }
   1001         else {
   1002             _mbstr_copy_ascii(dest, src+n_src, consume);
   1003         }
   1004 
   1005         if (n_src == 0) {
   1006             /* Either the real source of intpart digits or the virtual
   1007              * source of padding zeros is exhausted. */
   1008             if (spec->align == 'z' &&
   1009                 dest->nchars + n_sign < spec->min_width) {
   1010                 /* Zero padding is set and length < min_width:
   1011                  * Generate n_src additional characters. */
   1012                 n_src = spec->min_width - (dest->nchars + n_sign);
   1013                 /* Next iteration:
   1014                  *   case *g == 0 || *g == CHAR_MAX:
   1015                  *      consume all padding characters
   1016                  *   case consume < g*:
   1017                  *      fill remainder of current group
   1018                  *   case consume == g*
   1019                  *      copying is a no-op */
   1020                 consume = *g - consume;
   1021                 /* Switch on virtual source of zeros. */
   1022                 pad = 1;
   1023                 continue;
   1024             }
   1025             break;
   1026         }
   1027 
   1028         if (n_sep > 0) {
   1029             /* If padding is switched on, separators are counted
   1030              * as padding characters. This rule does not apply if
   1031              * the separator would be the first character of the
   1032              * result string. */
   1033             if (pad && n_src > 1) n_src -= 1;
   1034             _mbstr_copy_char(dest, spec->sep, n_sep);
   1035         }
   1036 
   1037         /* If non-NUL, use the next value for grouping. */
   1038         if (*g && *(g+1)) g++;
   1039         consume = *g;
   1040     }
   1041 
   1042     if (sign) {
   1043         _mbstr_copy_ascii(dest, sign, 1);
   1044     }
   1045 
   1046     if (dest->data) {
   1047         dest->data[dest->nbytes] = '\0';
   1048     }
   1049 }
   1050 
   1051 /*
   1052  * Convert a numeric-string to its locale-specific appearance.
   1053  * The string must have one of these forms:
   1054  *
   1055  *     1) [sign] digits [exponent-part]
   1056  *     2) [sign] digits '.' [digits] [exponent-part]
   1057  *
   1058  * Not allowed, since _mpd_to_string() never returns this form:
   1059  *
   1060  *     3) [sign] '.' digits [exponent-part]
   1061  *
   1062  * Input: result->data := original numeric string (ASCII)
   1063  *        result->bytes := strlen(result->data)
   1064  *        result->nchars := strlen(result->data)
   1065  *
   1066  * Output: result->data := modified or original string
   1067  *         result->bytes := strlen(result->data)
   1068  *         result->nchars := number of characters (possibly UTF-8)
   1069  */
   1070 static int
   1071 _mpd_apply_lconv(mpd_mbstr_t *result, const mpd_spec_t *spec, uint32_t *status)
   1072 {
   1073     const char *sign = NULL, *intpart = NULL, *dot = NULL;
   1074     const char *rest, *dp;
   1075     char *decstring;
   1076     mpd_ssize_t n_int, n_rest;
   1077 
   1078     /* original numeric string */
   1079     dp = result->data;
   1080 
   1081     /* sign */
   1082     if (*dp == '+' || *dp == '-' || *dp == ' ') {
   1083         sign = dp++;
   1084     }
   1085     /* integer part */
   1086     assert(isdigit((uchar)*dp));
   1087     intpart = dp++;
   1088     while (isdigit((uchar)*dp)) {
   1089         dp++;
   1090     }
   1091     n_int = (mpd_ssize_t)(dp-intpart);
   1092     /* decimal point */
   1093     if (*dp == '.') {
   1094         dp++; dot = spec->dot;
   1095     }
   1096     /* rest */
   1097     rest = dp;
   1098     n_rest = result->nbytes - (mpd_ssize_t)(dp-result->data);
   1099 
   1100     if (dot == NULL && (*spec->sep == '\0' || *spec->grouping == '\0')) {
   1101         /* _mpd_add_sep_dot() would not change anything */
   1102         return 1;
   1103     }
   1104 
   1105     /* Determine the size of the new decimal string after inserting the
   1106      * decimal point, optional separators and optional padding. */
   1107     decstring = result->data;
   1108     result->data = NULL;
   1109     _mpd_add_sep_dot(result, sign, intpart, n_int, dot,
   1110                      rest, n_rest, spec);
   1111 
   1112     result->data = mpd_alloc(result->nbytes+1, 1);
   1113     if (result->data == NULL) {
   1114         *status |= MPD_Malloc_error;
   1115         mpd_free(decstring);
   1116         return 0;
   1117     }
   1118 
   1119     /* Perform actual writes. */
   1120     _mpd_add_sep_dot(result, sign, intpart, n_int, dot,
   1121                      rest, n_rest, spec);
   1122 
   1123     mpd_free(decstring);
   1124     return 1;
   1125 }
   1126 
   1127 /* Add padding to the formatted string if necessary. */
   1128 static int
   1129 _mpd_add_pad(mpd_mbstr_t *result, const mpd_spec_t *spec, uint32_t *status)
   1130 {
   1131     if (result->nchars < spec->min_width) {
   1132         mpd_ssize_t add_chars, add_bytes;
   1133         size_t lpad = 0, rpad = 0;
   1134         size_t n_fill, len, i, j;
   1135         char align = spec->align;
   1136         uint8_t err = 0;
   1137         char *cp;
   1138 
   1139         n_fill = strlen(spec->fill);
   1140         add_chars = (spec->min_width - result->nchars);
   1141         /* max value: MPD_MAX_PREC * 4 */
   1142         add_bytes = add_chars * (mpd_ssize_t)n_fill;
   1143 
   1144         cp = result->data = mpd_realloc(result->data,
   1145                                         result->nbytes+add_bytes+1,
   1146                                         sizeof *result->data, &err);
   1147         if (err) {
   1148             *status |= MPD_Malloc_error;
   1149             mpd_free(result->data);
   1150             return 0;
   1151         }
   1152 
   1153         if (align == 'z') {
   1154             align = '=';
   1155         }
   1156 
   1157         if (align == '<') {
   1158             rpad = add_chars;
   1159         }
   1160         else if (align == '>' || align == '=') {
   1161             lpad = add_chars;
   1162         }
   1163         else { /* align == '^' */
   1164             lpad = add_chars/2;
   1165             rpad = add_chars-lpad;
   1166         }
   1167 
   1168         len = result->nbytes;
   1169         if (align == '=' && (*cp == '-' || *cp == '+' || *cp == ' ')) {
   1170             /* leave sign in the leading position */
   1171             cp++; len--;
   1172         }
   1173 
   1174         memmove(cp+n_fill*lpad, cp, len);
   1175         for (i = 0; i < lpad; i++) {
   1176             for (j = 0; j < n_fill; j++) {
   1177                 cp[i*n_fill+j] = spec->fill[j];
   1178             }
   1179         }
   1180         cp += (n_fill*lpad + len);
   1181         for (i = 0; i < rpad; i++) {
   1182             for (j = 0; j < n_fill; j++) {
   1183                 cp[i*n_fill+j] = spec->fill[j];
   1184             }
   1185         }
   1186 
   1187         result->nbytes += add_bytes;
   1188         result->nchars += add_chars;
   1189         result->data[result->nbytes] = '\0';
   1190     }
   1191 
   1192     return 1;
   1193 }
   1194 
   1195 /* Round a number to prec digits. The adjusted exponent stays the same
   1196    or increases by one if rounding up crosses a power of ten boundary.
   1197    If result->digits would exceed MPD_MAX_PREC+1, MPD_Invalid_operation
   1198    is set and the result is NaN. */
   1199 static inline void
   1200 _mpd_round(mpd_t *result, const mpd_t *a, mpd_ssize_t prec,
   1201            const mpd_context_t *ctx, uint32_t *status)
   1202 {
   1203     mpd_ssize_t exp = a->exp + a->digits - prec;
   1204 
   1205     if (prec <= 0) {
   1206         mpd_seterror(result, MPD_Invalid_operation, status); /* GCOV_NOT_REACHED */
   1207         return; /* GCOV_NOT_REACHED */
   1208     }
   1209     if (mpd_isspecial(a) || mpd_iszero(a)) {
   1210         mpd_qcopy(result, a, status); /* GCOV_NOT_REACHED */
   1211         return; /* GCOV_NOT_REACHED */
   1212     }
   1213 
   1214     mpd_qrescale_fmt(result, a, exp, ctx, status);
   1215     if (result->digits > prec) {
   1216         mpd_qrescale_fmt(result, result, exp+1, ctx, status);
   1217     }
   1218 }
   1219 
   1220 /*
   1221  * Return the string representation of an mpd_t, formatted according to 'spec'.
   1222  * The format specification is assumed to be valid. Memory errors are indicated
   1223  * as usual. This function is quiet.
   1224  */
   1225 char *
   1226 mpd_qformat_spec(const mpd_t *dec, const mpd_spec_t *spec,
   1227                  const mpd_context_t *ctx, uint32_t *status)
   1228 {
   1229     mpd_uint_t dt[MPD_MINALLOC_MAX];
   1230     mpd_t tmp = {MPD_STATIC|MPD_STATIC_DATA,0,0,0,MPD_MINALLOC_MAX,dt};
   1231     mpd_ssize_t dplace = MPD_DEFAULT_DOTPLACE;
   1232     mpd_mbstr_t result;
   1233     mpd_spec_t stackspec;
   1234     char type = spec->type;
   1235     int flags = 0;
   1236 
   1237 
   1238     if (spec->min_width > MPD_MAX_PREC) {
   1239         *status |= MPD_Invalid_operation;
   1240         return NULL;
   1241     }
   1242 
   1243     if (isupper((uchar)type)) {
   1244         type = tolower((uchar)type);
   1245         flags |= MPD_FMT_UPPER;
   1246     }
   1247     if (spec->sign == ' ') {
   1248         flags |= MPD_FMT_SIGN_SPACE;
   1249     }
   1250     else if (spec->sign == '+') {
   1251         flags |= MPD_FMT_SIGN_PLUS;
   1252     }
   1253 
   1254     if (mpd_isspecial(dec)) {
   1255         if (spec->align == 'z') {
   1256             stackspec = *spec;
   1257             stackspec.fill[0] = ' ';
   1258             stackspec.fill[1] = '\0';
   1259             stackspec.align = '>';
   1260             spec = &stackspec;
   1261         }
   1262         if (type == '%') {
   1263             flags |= MPD_FMT_PERCENT;
   1264         }
   1265     }
   1266     else {
   1267         uint32_t workstatus = 0;
   1268         mpd_ssize_t prec;
   1269 
   1270         switch (type) {
   1271         case 'g': flags |= MPD_FMT_TOSCI; break;
   1272         case 'e': flags |= MPD_FMT_EXP; break;
   1273         case '%': flags |= MPD_FMT_PERCENT;
   1274                   if (!mpd_qcopy(&tmp, dec, status)) {
   1275                       return NULL;
   1276                   }
   1277                   tmp.exp += 2;
   1278                   dec = &tmp;
   1279                   type = 'f'; /* fall through */
   1280         case 'f': flags |= MPD_FMT_FIXED; break;
   1281         default: abort(); /* debug: GCOV_NOT_REACHED */
   1282         }
   1283 
   1284         if (spec->prec >= 0) {
   1285             if (spec->prec > MPD_MAX_PREC) {
   1286                 *status |= MPD_Invalid_operation;
   1287                 goto error;
   1288             }
   1289 
   1290             switch (type) {
   1291             case 'g':
   1292                 prec = (spec->prec == 0) ? 1 : spec->prec;
   1293                 if (dec->digits > prec) {
   1294                     _mpd_round(&tmp, dec, prec, ctx,
   1295                                &workstatus);
   1296                     dec = &tmp;
   1297                 }
   1298                 break;
   1299             case 'e':
   1300                 if (mpd_iszero(dec)) {
   1301                     dplace = 1-spec->prec;
   1302                 }
   1303                 else {
   1304                     _mpd_round(&tmp, dec, spec->prec+1, ctx,
   1305                                &workstatus);
   1306                     dec = &tmp;
   1307                 }
   1308                 break;
   1309             case 'f':
   1310                 mpd_qrescale(&tmp, dec, -spec->prec, ctx,
   1311                              &workstatus);
   1312                 dec = &tmp;
   1313                 break;
   1314             }
   1315         }
   1316 
   1317         if (type == 'f') {
   1318             if (mpd_iszero(dec) && dec->exp > 0) {
   1319                 mpd_qrescale(&tmp, dec, 0, ctx, &workstatus);
   1320                 dec = &tmp;
   1321             }
   1322         }
   1323 
   1324         if (workstatus&MPD_Errors) {
   1325             *status |= (workstatus&MPD_Errors);
   1326             goto error;
   1327         }
   1328     }
   1329 
   1330     /*
   1331      * At this point, for all scaled or non-scaled decimals:
   1332      *   1) 1 <= digits <= MAX_PREC+1
   1333      *   2) adjexp(scaled) = adjexp(orig) [+1]
   1334      *   3)   case 'g': MIN_ETINY <= exp <= MAX_EMAX+1
   1335      *        case 'e': MIN_ETINY-MAX_PREC <= exp <= MAX_EMAX+1
   1336      *        case 'f': MIN_ETINY <= exp <= MAX_EMAX+1
   1337      *   4) max memory alloc in _mpd_to_string:
   1338      *        case 'g': MAX_PREC+36
   1339      *        case 'e': MAX_PREC+36
   1340      *        case 'f': 2*MPD_MAX_PREC+30
   1341      */
   1342     result.nbytes = _mpd_to_string(&result.data, dec, flags, dplace);
   1343     result.nchars = result.nbytes;
   1344     if (result.nbytes < 0) {
   1345         *status |= MPD_Malloc_error;
   1346         goto error;
   1347     }
   1348 
   1349     if (*spec->dot != '\0' && !mpd_isspecial(dec)) {
   1350         if (result.nchars > MPD_MAX_PREC+36) {
   1351             /* Since a group length of one is not explicitly
   1352              * disallowed, ensure that it is always possible to
   1353              * insert a four byte separator after each digit. */
   1354             *status |= MPD_Invalid_operation;
   1355             mpd_free(result.data);
   1356             goto error;
   1357         }
   1358         if (!_mpd_apply_lconv(&result, spec, status)) {
   1359             goto error;
   1360         }
   1361     }
   1362 
   1363     if (spec->min_width) {
   1364         if (!_mpd_add_pad(&result, spec, status)) {
   1365             goto error;
   1366         }
   1367     }
   1368 
   1369     mpd_del(&tmp);
   1370     return result.data;
   1371 
   1372 error:
   1373     mpd_del(&tmp);
   1374     return NULL;
   1375 }
   1376 
   1377 char *
   1378 mpd_qformat(const mpd_t *dec, const char *fmt, const mpd_context_t *ctx,
   1379             uint32_t *status)
   1380 {
   1381     mpd_spec_t spec;
   1382 
   1383     if (!mpd_parse_fmt_str(&spec, fmt, 1)) {
   1384         *status |= MPD_Invalid_operation;
   1385         return NULL;
   1386     }
   1387 
   1388     return mpd_qformat_spec(dec, &spec, ctx, status);
   1389 }
   1390 
   1391 /*
   1392  * The specification has a *condition* called Invalid_operation and an
   1393  * IEEE *signal* called Invalid_operation. The former corresponds to
   1394  * MPD_Invalid_operation, the latter to MPD_IEEE_Invalid_operation.
   1395  * MPD_IEEE_Invalid_operation comprises the following conditions:
   1396  *
   1397  * [MPD_Conversion_syntax, MPD_Division_impossible, MPD_Division_undefined,
   1398  *  MPD_Fpu_error, MPD_Invalid_context, MPD_Invalid_operation,
   1399  *  MPD_Malloc_error]
   1400  *
   1401  * In the following functions, 'flag' denotes the condition, 'signal'
   1402  * denotes the IEEE signal.
   1403  */
   1404 
   1405 static const char *mpd_flag_string[MPD_NUM_FLAGS] = {
   1406     "Clamped",
   1407     "Conversion_syntax",
   1408     "Division_by_zero",
   1409     "Division_impossible",
   1410     "Division_undefined",
   1411     "Fpu_error",
   1412     "Inexact",
   1413     "Invalid_context",
   1414     "Invalid_operation",
   1415     "Malloc_error",
   1416     "Not_implemented",
   1417     "Overflow",
   1418     "Rounded",
   1419     "Subnormal",
   1420     "Underflow",
   1421 };
   1422 
   1423 static const char *mpd_signal_string[MPD_NUM_FLAGS] = {
   1424     "Clamped",
   1425     "IEEE_Invalid_operation",
   1426     "Division_by_zero",
   1427     "IEEE_Invalid_operation",
   1428     "IEEE_Invalid_operation",
   1429     "IEEE_Invalid_operation",
   1430     "Inexact",
   1431     "IEEE_Invalid_operation",
   1432     "IEEE_Invalid_operation",
   1433     "IEEE_Invalid_operation",
   1434     "Not_implemented",
   1435     "Overflow",
   1436     "Rounded",
   1437     "Subnormal",
   1438     "Underflow",
   1439 };
   1440 
   1441 /* print conditions to buffer, separated by spaces */
   1442 int
   1443 mpd_snprint_flags(char *dest, int nmemb, uint32_t flags)
   1444 {
   1445     char *cp;
   1446     int n, j;
   1447 
   1448     assert(nmemb >= MPD_MAX_FLAG_STRING);
   1449 
   1450     *dest = '\0'; cp = dest;
   1451     for (j = 0; j < MPD_NUM_FLAGS; j++) {
   1452         if (flags & (1U<<j)) {
   1453             n = snprintf(cp, nmemb, "%s ", mpd_flag_string[j]);
   1454             if (n < 0 || n >= nmemb) return -1;
   1455             cp += n; nmemb -= n;
   1456         }
   1457     }
   1458 
   1459     if (cp != dest) {
   1460         *(--cp) = '\0';
   1461     }
   1462 
   1463     return (int)(cp-dest);
   1464 }
   1465 
   1466 /* print conditions to buffer, in list form */
   1467 int
   1468 mpd_lsnprint_flags(char *dest, int nmemb, uint32_t flags, const char *flag_string[])
   1469 {
   1470     char *cp;
   1471     int n, j;
   1472 
   1473     assert(nmemb >= MPD_MAX_FLAG_LIST);
   1474     if (flag_string == NULL) {
   1475         flag_string = mpd_flag_string;
   1476     }
   1477 
   1478     *dest = '[';
   1479     *(dest+1) = '\0';
   1480     cp = dest+1;
   1481     --nmemb;
   1482 
   1483     for (j = 0; j < MPD_NUM_FLAGS; j++) {
   1484         if (flags & (1U<<j)) {
   1485             n = snprintf(cp, nmemb, "%s, ", flag_string[j]);
   1486             if (n < 0 || n >= nmemb) return -1;
   1487             cp += n; nmemb -= n;
   1488         }
   1489     }
   1490 
   1491     /* erase the last ", " */
   1492     if (cp != dest+1) {
   1493         cp -= 2;
   1494     }
   1495 
   1496     *cp++ = ']';
   1497     *cp = '\0';
   1498 
   1499     return (int)(cp-dest); /* strlen, without NUL terminator */
   1500 }
   1501 
   1502 /* print signals to buffer, in list form */
   1503 int
   1504 mpd_lsnprint_signals(char *dest, int nmemb, uint32_t flags, const char *signal_string[])
   1505 {
   1506     char *cp;
   1507     int n, j;
   1508     int ieee_invalid_done = 0;
   1509 
   1510     assert(nmemb >= MPD_MAX_SIGNAL_LIST);
   1511     if (signal_string == NULL) {
   1512         signal_string = mpd_signal_string;
   1513     }
   1514 
   1515     *dest = '[';
   1516     *(dest+1) = '\0';
   1517     cp = dest+1;
   1518     --nmemb;
   1519 
   1520     for (j = 0; j < MPD_NUM_FLAGS; j++) {
   1521         uint32_t f = flags & (1U<<j);
   1522         if (f) {
   1523             if (f&MPD_IEEE_Invalid_operation) {
   1524                 if (ieee_invalid_done) {
   1525                     continue;
   1526                 }
   1527                 ieee_invalid_done = 1;
   1528             }
   1529             n = snprintf(cp, nmemb, "%s, ", signal_string[j]);
   1530             if (n < 0 || n >= nmemb) return -1;
   1531             cp += n; nmemb -= n;
   1532         }
   1533     }
   1534 
   1535     /* erase the last ", " */
   1536     if (cp != dest+1) {
   1537         cp -= 2;
   1538     }
   1539 
   1540     *cp++ = ']';
   1541     *cp = '\0';
   1542 
   1543     return (int)(cp-dest); /* strlen, without NUL terminator */
   1544 }
   1545 
   1546 /* The following two functions are mainly intended for debugging. */
   1547 void
   1548 mpd_fprint(FILE *file, const mpd_t *dec)
   1549 {
   1550     char *decstring;
   1551 
   1552     decstring = mpd_to_sci(dec, 1);
   1553     if (decstring != NULL) {
   1554         fprintf(file, "%s\n", decstring);
   1555         mpd_free(decstring);
   1556     }
   1557     else {
   1558         fputs("mpd_fprint: output error\n", file); /* GCOV_NOT_REACHED */
   1559     }
   1560 }
   1561 
   1562 void
   1563 mpd_print(const mpd_t *dec)
   1564 {
   1565     char *decstring;
   1566 
   1567     decstring = mpd_to_sci(dec, 1);
   1568     if (decstring != NULL) {
   1569         printf("%s\n", decstring);
   1570         mpd_free(decstring);
   1571     }
   1572     else {
   1573         fputs("mpd_fprint: output error\n", stderr); /* GCOV_NOT_REACHED */
   1574     }
   1575 }
   1576 
   1577 
   1578