summaryrefslogtreecommitdiff
path: root/strings/strto.c
blob: 8255c38f52e88e280fedd0a40f34814fffd2ffe4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
/* Copyright (c) 2000-2004, 2006, 2007 MySQL AB
   Use is subject to license terms.

   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; version 2 of the License.

   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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  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 uchar 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 == '\0')
  {
    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 != '\0'; 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;
}