gl/lib/xdectoint.c

   1 /* Convert decimal strings with bounds checking and exit on error.
   2
   3    Copyright (C) 2014-2024 Free Software Foundation, Inc.
   4
   5    This program is free software: you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 3 of the License, or
   8    (at your option) any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  17
  18 #include <config.h>
  19
  20 #include "xdectoint.h"
  21
  22 #include <errno.h>
  23 #include <inttypes.h>
  24 #include <stdlib.h>
  25
  26 #include <error.h>
  27 #include <quote.h>
  28 #include <xstrtol.h>
  29
  30 /* Parse numeric string N_STR of base BASE, and return the value.
  31    The value is between MIN and MAX.
  32    Strings can have multiplicative SUFFIXES if specified.
  33    On a parse error or out-of-range number, diagnose with N_STR and ERR, and
  34    exit with status ERR_EXIT if nonzero, EXIT_FAILURE otherwise.
  35    However, if FLAGS & XTOINT_MIN_QUIET, do not diagnose or exit
  36    for too-low numbers; return MIN and set errno instead.
  37    Similarly for XTOINT_MAX_QUIET and too-high numbers and MAX.
  38    The errno value and diagnostic for out-of-range values depend on
  39    whether FLAGS & XTOINT_MIN_RANGE and FLAGS & XTOINT_MAX_RANGE are set.  */
  40
  41 __xdectoint_t
  42 __xnumtoint (char const *n_str, int base, __xdectoint_t min, __xdectoint_t max,
  43              char const *suffixes, char const *err, int err_exit,
  44              int flags)
  45 {
  46   __xdectoint_t tnum, r;
  47   strtol_error s_err = __xstrtol (n_str, nullptr, base, &tnum, suffixes);
  48
  49   /* Errno value to report if there is an overflow.  */
  50   int overflow_errno;
  51
  52   if (s_err != LONGINT_INVALID)
  53     {
  54       if (tnum < min)
  55         {
  56           r = min;
  57           overflow_errno = flags & XTOINT_MIN_RANGE ? ERANGE : EOVERFLOW;
  58           if (s_err == LONGINT_OK)
  59             s_err = LONGINT_OVERFLOW;
  60         }
  61       else if (max < tnum)
  62         {
  63           r = max;
  64           overflow_errno = flags & XTOINT_MAX_RANGE ? ERANGE : EOVERFLOW;
  65           if (s_err == LONGINT_OK)
  66             s_err = LONGINT_OVERFLOW;
  67         }
  68       else
  69         {
  70           r = tnum;
  71           overflow_errno = EOVERFLOW;
  72         }
  73     }
  74
  75   int e = s_err == LONGINT_OVERFLOW ? overflow_errno : 0;
  76
  77   if (! (s_err == LONGINT_OK
  78          || (s_err == LONGINT_OVERFLOW
  79              && flags & (tnum < 0 ? XTOINT_MIN_QUIET : XTOINT_MAX_QUIET))))
  80     error (err_exit ? err_exit : EXIT_FAILURE, e, "%s: %s", err, quote (n_str));
  81
  82   errno = e;
  83   return r;
  84 }
  85
  86 /* Parse decimal string N_STR, and return the value.
  87    Exit on parse error or if MIN or MAX are exceeded.
  88    Strings can have multiplicative SUFFIXES if specified.
  89    ERR is printed along with N_STR on error.  */
  90
  91 __xdectoint_t
  92 __xdectoint (char const *n_str, __xdectoint_t min, __xdectoint_t max,
  93              char const *suffixes, char const *err, int err_exit)
  94 {
  95   return __xnumtoint (n_str, 10, min, max, suffixes, err, err_exit, 0);
  96 }