strto.c
上传用户:romrleung
上传日期:2022-05-23
资源大小:18897k
文件大小:5k
- /* Copyright (C) 2000 MySQL AB
- This program 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 2 of the License, or
- (at your option) any later version.
- This program 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 this program; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
- /*
- strtol,strtoul,strtoll,strtoull
- convert string to long, unsigned long, long long or unsigned long long.
- strtoxx(char *src,char **ptr,int base)
- converts the string pointed to by src to an long of appropriate long and
- returnes it. It skips leading spaces and tabs (but not newlines, formfeeds,
- backspaces), then it accepts an optional sign and a sequence of digits
- in the specified radix.
- If the value of ptr is not (char **)NULL, a pointer to the character
- terminating the scan is returned in the location pointed to by ptr.
- Trailing spaces will NOT be skipped.
- If an error is detected, the result will be LONG_MIN, 0 or LONG_MAX,
- (or LONGLONG..) and errno will be set to
- EDOM if there are no digits
- ERANGE if the result would overflow.
- the ptr will be set to src.
- This file is based on the strtol from the the GNU C Library.
- it can be compiled with the UNSIGNED and/or LONGLONG flag set
- */
- #if !defined(_global_h) || !defined(_m_string_h)
- # error Calling file must include 'my_global.h' and 'm_string.h'
- /* see 'strtoll.c' and 'strtoull.c' for the reasons */
- #endif
- #include "m_ctype.h"
- #include "my_sys.h" /* defines errno */
- #include <errno.h>
- #undef strtoull
- #undef strtoll
- #undef strtoul
- #undef strtol
- #ifdef USE_LONGLONG
- #define UTYPE_MAX (~(ulonglong) 0)
- #define TYPE_MIN LONGLONG_MIN
- #define TYPE_MAX LONGLONG_MAX
- #define longtype longlong
- #define ulongtype ulonglong
- #ifdef USE_UNSIGNED
- #define function ulongtype strtoull
- #else
- #define function longtype strtoll
- #endif
- #else
- #define UTYPE_MAX (ulong) ~0L
- #define TYPE_MIN LONG_MIN
- #define TYPE_MAX LONG_MAX
- #define longtype long
- #define ulongtype unsigned long
- #ifdef USE_UNSIGNED
- #define function ulongtype strtoul
- #else
- #define function longtype strtol
- #endif
- #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 reset to 10.
- If ENDPTR is not NULL, a pointer to the character after the last
- one converted is stored in *ENDPTR. */
- function (const char *nptr,char **endptr,int base)
- {
- int negative;
- register ulongtype cutoff;
- register unsigned int cutlim;
- register ulongtype i;
- register const char *s;
- register unsigned char c;
- const char *save;
- int overflow;
- if (base < 0 || base == 1 || base > 36)
- base = 10;
- s = nptr;
- /* Skip white space. */
- while (my_isspace(&my_charset_latin1, *s))
- ++s;
- if (*s == ' ')
- {
- goto noconv;
- }
- /* Check for a sign. */
- negative= 0;
- if (*s == '-')
- {
- negative = 1;
- ++s;
- }
- else if (*s == '+')
- {
- ++s;
- }
-
- if (base == 16 && s[0] == '0' && my_toupper (&my_charset_latin1, s[1]) == 'X')
- s += 2;
- /* If BASE is zero, figure it out ourselves. */
- if (base == 0)
- {
- if (*s == '0')
- {
- if (my_toupper (&my_charset_latin1, s[1]) == 'X')
- {
- s += 2;
- base = 16;
- }
- else
- base = 8;
- }
- else
- base = 10;
- }
- /* Save the pointer so we can check later if anything happened. */
- save = s;
- cutoff = UTYPE_MAX / (unsigned long int) base;
- cutlim = (uint) (UTYPE_MAX % (unsigned long int) base);
- overflow = 0;
- i = 0;
- for (c = *s; c != ' '; c = *++s)
- {
- if (my_isdigit (&my_charset_latin1, c))
- c -= '0';
- else if (my_isalpha (&my_charset_latin1, c))
- c = my_toupper (&my_charset_latin1, c) - 'A' + 10;
- else
- break;
- if (c >= base)
- break;
- /* Check for overflow. */
- if (i > cutoff || (i == cutoff && c > cutlim))
- overflow = 1;
- else
- {
- i *= (ulongtype) 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;
- #ifndef USE_UNSIGNED
- /* Check for a value that is within the range of
- `unsigned long int', but outside the range of `long int'. */
- if (negative)
- {
- if (i > (ulongtype) TYPE_MIN)
- overflow = 1;
- }
- else if (i > (ulongtype) TYPE_MAX)
- overflow = 1;
- #endif
- if (overflow)
- {
- my_errno=ERANGE;
- #ifdef USE_UNSIGNED
- return UTYPE_MAX;
- #else
- return negative ? TYPE_MIN : TYPE_MAX;
- #endif
- }
- /* Return the result of the appropriate sign. */
- return (negative ? -((longtype) i) : (longtype) i);
- noconv:
- /* There was no number to convert. */
- my_errno=EDOM;
- if (endptr != NULL)
- *endptr = (char *) nptr;
- return 0L;
- }