📄 strtol.c
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/* strtol - convert string representation of a number into a long integer value. *//* Copyright (C) 1991,92,94,95,96,97,98,99,2000,2001 Free Software Foundation, Inc. This file is part of GNU Bash, the Bourne Again SHell. Bash is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. Bash is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with Bash. If not, see <http://www.gnu.org/licenses/>.*/#include <config.h>#if !defined (HAVE_STRTOL)#include <chartypes.h>#include <errno.h>#ifndef errnoextern int errno;#endif#ifndef __set_errno# define __set_errno(Val) errno = (Val)#endif#ifdef HAVE_LIMITS_H# include <limits.h>#endif#include <typemax.h>#include <stdc.h>#include <bashansi.h>#ifndef NULL# define NULL 0#endif/* Nonzero if we are defining `strtoul' or `strtoull', operating on unsigned integers. */#ifndef UNSIGNED# define UNSIGNED 0# define INT LONG int#else# define INT unsigned LONG int#endif#if UNSIGNED# ifdef QUAD# define strtol strtoull# else# define strtol strtoul# endif#else# ifdef QUAD# define strtol strtoll# endif#endif/* If QUAD is defined, we are defining `strtoll' or `strtoull', operating on `long long ints. */#ifdef QUAD# define LONG long long# define STRTOL_LONG_MIN LLONG_MIN# define STRTOL_LONG_MAX LLONG_MAX# define STRTOL_ULONG_MAX ULLONG_MAX#else /* !QUAD */# define LONG long# define STRTOL_LONG_MIN LONG_MIN# define STRTOL_LONG_MAX LONG_MAX# define STRTOL_ULONG_MAX ULONG_MAX#endif/* Convert NPTR to an `unsigned long int' or `long int' in base BASE. If BASE is 0 the base is determined by the presence of a leading zero, indicating octal or a leading "0x" or "0X", indicating hexadecimal. If BASE is < 2 or > 36, it is no longer reset to 10; EINVAL is returned. If ENDPTR is not NULL, a pointer to the character after the last one converted is stored in *ENDPTR. */INTstrtol (nptr, endptr, base) const char *nptr; char **endptr; int base;{ int negative; register unsigned LONG int cutoff; register unsigned int cutlim; register unsigned LONG int i; register const char *s; register unsigned char c; const char *save, *end; int overflow; if (base < 0 || base == 1 || base > 36) { __set_errno (EINVAL); return 0; } save = s = nptr; /* Skip white space. */ while (ISSPACE ((unsigned char)*s)) ++s; if (*s == '\0') goto noconv; /* Check for a sign. */ if (*s == '-' || *s == '+') { negative = (*s == '-'); ++s; } else negative = 0; /* Recognize number prefix and if BASE is zero, figure it out ourselves. */ if (*s == '0') { if ((base == 0 || base == 16) && TOUPPER ((unsigned char) s[1]) == 'X') { s += 2; base = 16; } else if (base == 0) base = 8; } else if (base == 0) base = 10; /* Save the pointer so we can check later if anything happened. */ save = s; end = NULL; cutoff = STRTOL_ULONG_MAX / (unsigned LONG int) base; cutlim = STRTOL_ULONG_MAX % (unsigned LONG int) base; overflow = 0; i = 0; c = *s; if (sizeof (long int) != sizeof (LONG int)) { unsigned long int j = 0; unsigned long int jmax = ULONG_MAX / base; for (;c != '\0'; c = *++s) { if (s == end) break; if (DIGIT (c)) c -= '0'; else if (ISALPHA (c)) c = TOUPPER (c) - 'A' + 10; else break; if ((int) c >= base) break; /* Note that we never can have an overflow. */ else if (j >= jmax) { /* We have an overflow. Now use the long representation. */ i = (unsigned LONG int) j; goto use_long; } else j = j * (unsigned long int) base + c; } i = (unsigned LONG int) j; } else for (;c != '\0'; c = *++s) { if (s == end) break; if (DIGIT (c)) c -= '0'; else if (ISALPHA (c)) c = TOUPPER (c) - 'A' + 10; else break; if ((int) c >= base) break; /* Check for overflow. */ if (i > cutoff || (i == cutoff && c > cutlim)) overflow = 1; else { use_long: i *= (unsigned LONG int) base; i += c; } } /* Check if anything actually happened. */ if (s == save) goto noconv; /* Store in ENDPTR the address of one character past the last character we converted. */ if (endptr != NULL) *endptr = (char *) s;#if !UNSIGNED /* Check for a value that is within the range of `unsigned LONG int', but outside the range of `LONG int'. */ if (overflow == 0 && i > (negative ? -((unsigned LONG int) (STRTOL_LONG_MIN + 1)) + 1 : (unsigned LONG int) STRTOL_LONG_MAX)) overflow = 1;#endif if (overflow) { __set_errno (ERANGE);#if UNSIGNED return STRTOL_ULONG_MAX;#else return negative ? STRTOL_LONG_MIN : STRTOL_LONG_MAX;#endif } /* Return the result of the appropriate sign. */ return negative ? -i : i;noconv: /* We must handle a special case here: the base is 0 or 16 and the first two characters are '0' and 'x', but the rest are no hexadecimal digits. This is no error case. We return 0 and ENDPTR points to the `x`. */ if (endptr != NULL) { if (save - nptr >= 2 && TOUPPER ((unsigned char) save[-1]) == 'X' && save[-2] == '0') *endptr = (char *) &save[-1]; else /* There was no number to convert. */ *endptr = (char *) nptr; } return 0L;}#endif /* !HAVE_STRTOL */
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