1 /* Convert string representation of a number into an integer value.
2
3 Copyright (C) 1991-1992, 1994-1999, 2003, 2005-2007, 2009-2020 Free Software
4 Foundation, Inc.
5
6 NOTE: The canonical source of this file is maintained with the GNU C
7 Library. Bugs can be reported to bug-glibc@gnu.org.
8
9 This program is free software: you can redistribute it and/or modify it
10 under the terms of the GNU General Public License as published by the
11 Free Software Foundation; either version 3 of the License, or any
12 later version.
13
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
18
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <https://www.gnu.org/licenses/>. */
21
22 #ifdef _LIBC
23 # define USE_NUMBER_GROUPING
24 #else
25 # include <config.h>
26 #endif
27
28 #include <ctype.h>
29 #include <errno.h>
30 #ifndef __set_errno
31 # define __set_errno(Val) errno = (Val)
32 #endif
33
34 #include <limits.h>
35 #include <stddef.h>
36 #include <stdlib.h>
37 #include <string.h>
38
39 #ifdef USE_NUMBER_GROUPING
40 # include "../locale/localeinfo.h"
41 #endif
42
43 /* Nonzero if we are defining 'strtoul' or 'strtoull', operating on
44 unsigned integers. */
45 #ifndef UNSIGNED
46 # define UNSIGNED 0
47 # define INT LONG int
48 #else
49 # define INT unsigned LONG int
50 #endif
51
52 /* Determine the name. */
53 #ifdef USE_IN_EXTENDED_LOCALE_MODEL
54 # if UNSIGNED
55 # ifdef USE_WIDE_CHAR
56 # ifdef QUAD
57 # define strtol __wcstoull_l
58 # else
59 # define strtol __wcstoul_l
60 # endif
61 # else
62 # ifdef QUAD
63 # define strtol __strtoull_l
64 # else
65 # define strtol __strtoul_l
66 # endif
67 # endif
68 # else
69 # ifdef USE_WIDE_CHAR
70 # ifdef QUAD
71 # define strtol __wcstoll_l
72 # else
73 # define strtol __wcstol_l
74 # endif
75 # else
76 # ifdef QUAD
77 # define strtol __strtoll_l
78 # else
79 # define strtol __strtol_l
80 # endif
81 # endif
82 # endif
83 #else
84 # if UNSIGNED
85 # ifdef USE_WIDE_CHAR
86 # ifdef QUAD
87 # define strtol wcstoull
88 # else
89 # define strtol wcstoul
90 # endif
91 # else
92 # ifdef QUAD
93 # define strtol strtoull
94 # else
95 # define strtol strtoul
96 # endif
97 # endif
98 # else
99 # ifdef USE_WIDE_CHAR
100 # ifdef QUAD
101 # define strtol wcstoll
102 # else
103 # define strtol wcstol
104 # endif
105 # else
106 # ifdef QUAD
107 # define strtol strtoll
108 # endif
109 # endif
110 # endif
111 #endif
112
113 /* If QUAD is defined, we are defining 'strtoll' or 'strtoull',
114 operating on 'long long int's. */
115 #ifdef QUAD
116 # define LONG long long
117 # define STRTOL_LONG_MIN LLONG_MIN
118 # define STRTOL_LONG_MAX LLONG_MAX
119 # define STRTOL_ULONG_MAX ULLONG_MAX
120 # if __GNUC__ == 2 && __GNUC_MINOR__ < 7
121 /* Work around gcc bug with using this constant. */
122 static const unsigned long long int maxquad = ULLONG_MAX;
123 # undef STRTOL_ULONG_MAX
124 # define STRTOL_ULONG_MAX maxquad
125 # endif
126 #else
127 # define LONG long
128 # define STRTOL_LONG_MIN LONG_MIN
129 # define STRTOL_LONG_MAX LONG_MAX
130 # define STRTOL_ULONG_MAX ULONG_MAX
131 #endif
132
133
134 /* We use this code also for the extended locale handling where the
135 function gets as an additional argument the locale which has to be
136 used. To access the values we have to redefine the _NL_CURRENT
137 macro. */
138 #ifdef USE_IN_EXTENDED_LOCALE_MODEL
139 # undef _NL_CURRENT
140 # define _NL_CURRENT(category, item) \
141 (current->values[_NL_ITEM_INDEX (item)].string)
142 # define LOCALE_PARAM , loc
143 # define LOCALE_PARAM_PROTO , __locale_t loc
144 #else
145 # define LOCALE_PARAM
146 # define LOCALE_PARAM_PROTO
147 #endif
148
149 #ifdef USE_WIDE_CHAR
150 # include <wchar.h>
151 # include <wctype.h>
152 # define L_(Ch) L##Ch
153 # define UCHAR_TYPE wint_t
154 # define STRING_TYPE wchar_t
155 # ifdef USE_IN_EXTENDED_LOCALE_MODEL
156 # define ISSPACE(Ch) __iswspace_l ((Ch), loc)
157 # define ISALPHA(Ch) __iswalpha_l ((Ch), loc)
158 # define TOUPPER(Ch) __towupper_l ((Ch), loc)
159 # else
160 # define ISSPACE(Ch) iswspace (Ch)
161 # define ISALPHA(Ch) iswalpha (Ch)
162 # define TOUPPER(Ch) towupper (Ch)
163 # endif
164 #else
165 # define L_(Ch) Ch
166 # define UCHAR_TYPE unsigned char
167 # define STRING_TYPE char
168 # ifdef USE_IN_EXTENDED_LOCALE_MODEL
169 # define ISSPACE(Ch) __isspace_l ((Ch), loc)
170 # define ISALPHA(Ch) __isalpha_l ((Ch), loc)
171 # define TOUPPER(Ch) __toupper_l ((Ch), loc)
172 # else
173 # define ISSPACE(Ch) isspace (Ch)
174 # define ISALPHA(Ch) isalpha (Ch)
175 # define TOUPPER(Ch) toupper (Ch)
176 # endif
177 #endif
178
179 #define INTERNAL(X) INTERNAL1(X)
180 #define INTERNAL1(X) __##X##_internal
181 #define WEAKNAME(X) WEAKNAME1(X)
182
183 #ifdef USE_NUMBER_GROUPING
184 /* This file defines a function to check for correct grouping. */
185 # include "grouping.h"
186 #endif
187
188
189
190 /* Convert NPTR to an 'unsigned long int' or 'long int' in base BASE.
191 If BASE is 0 the base is determined by the presence of a leading
192 zero, indicating octal or a leading "0x" or "0X", indicating hexadecimal.
193 If BASE is < 2 or > 36, it is reset to 10.
194 If ENDPTR is not NULL, a pointer to the character after the last
195 one converted is stored in *ENDPTR. */
196
197 INT
INTERNAL(strtol)198 INTERNAL (strtol) (const STRING_TYPE *nptr, STRING_TYPE **endptr,
199 int base, int group LOCALE_PARAM_PROTO)
200 {
201 int negative;
202 register unsigned LONG int cutoff;
203 register unsigned int cutlim;
204 register unsigned LONG int i;
205 register const STRING_TYPE *s;
206 register UCHAR_TYPE c;
207 const STRING_TYPE *save, *end;
208 int overflow;
209
210 #ifdef USE_NUMBER_GROUPING
211 # ifdef USE_IN_EXTENDED_LOCALE_MODEL
212 struct locale_data *current = loc->__locales[LC_NUMERIC];
213 # endif
214 /* The thousands character of the current locale. */
215 wchar_t thousands = L'\0';
216 /* The numeric grouping specification of the current locale,
217 in the format described in <locale.h>. */
218 const char *grouping;
219
220 if (group)
221 {
222 grouping = _NL_CURRENT (LC_NUMERIC, GROUPING);
223 if (*grouping <= 0 || *grouping == CHAR_MAX)
224 grouping = NULL;
225 else
226 {
227 /* Figure out the thousands separator character. */
228 # if defined _LIBC || defined _HAVE_BTOWC
229 thousands = __btowc (*_NL_CURRENT (LC_NUMERIC, THOUSANDS_SEP));
230 if (thousands == WEOF)
231 thousands = L'\0';
232 # endif
233 if (thousands == L'\0')
234 grouping = NULL;
235 }
236 }
237 else
238 grouping = NULL;
239 #endif
240
241 if (base < 0 || base == 1 || base > 36)
242 {
243 __set_errno (EINVAL);
244 return 0;
245 }
246
247 save = s = nptr;
248
249 /* Skip white space. */
250 while (ISSPACE (*s))
251 ++s;
252 if (*s == L_('\0'))
253 goto noconv;
254
255 /* Check for a sign. */
256 if (*s == L_('-'))
257 {
258 negative = 1;
259 ++s;
260 }
261 else if (*s == L_('+'))
262 {
263 negative = 0;
264 ++s;
265 }
266 else
267 negative = 0;
268
269 /* Recognize number prefix and if BASE is zero, figure it out ourselves. */
270 if (*s == L_('0'))
271 {
272 if ((base == 0 || base == 16) && TOUPPER (s[1]) == L_('X'))
273 {
274 s += 2;
275 base = 16;
276 }
277 else if (base == 0)
278 base = 8;
279 }
280 else if (base == 0)
281 base = 10;
282
283 /* Save the pointer so we can check later if anything happened. */
284 save = s;
285
286 #ifdef USE_NUMBER_GROUPING
287 if (group)
288 {
289 /* Find the end of the digit string and check its grouping. */
290 end = s;
291 for (c = *end; c != L_('\0'); c = *++end)
292 if ((wchar_t) c != thousands
293 && ((wchar_t) c < L_('0') || (wchar_t) c > L_('9'))
294 && (!ISALPHA (c) || (int) (TOUPPER (c) - L_('A') + 10) >= base))
295 break;
296 if (*s == thousands)
297 end = s;
298 else
299 end = correctly_grouped_prefix (s, end, thousands, grouping);
300 }
301 else
302 #endif
303 end = NULL;
304
305 cutoff = STRTOL_ULONG_MAX / (unsigned LONG int) base;
306 cutlim = STRTOL_ULONG_MAX % (unsigned LONG int) base;
307
308 overflow = 0;
309 i = 0;
310 for (c = *s; c != L_('\0'); c = *++s)
311 {
312 if (s == end)
313 break;
314 if (c >= L_('0') && c <= L_('9'))
315 c -= L_('0');
316 else if (ISALPHA (c))
317 c = TOUPPER (c) - L_('A') + 10;
318 else
319 break;
320 if ((int) c >= base)
321 break;
322 /* Check for overflow. */
323 if (i > cutoff || (i == cutoff && c > cutlim))
324 overflow = 1;
325 else
326 {
327 i *= (unsigned LONG int) base;
328 i += c;
329 }
330 }
331
332 /* Check if anything actually happened. */
333 if (s == save)
334 goto noconv;
335
336 /* Store in ENDPTR the address of one character
337 past the last character we converted. */
338 if (endptr != NULL)
339 *endptr = (STRING_TYPE *) s;
340
341 #if !UNSIGNED
342 /* Check for a value that is within the range of
343 'unsigned LONG int', but outside the range of 'LONG int'. */
344 if (overflow == 0
345 && i > (negative
346 ? -((unsigned LONG int) (STRTOL_LONG_MIN + 1)) + 1
347 : (unsigned LONG int) STRTOL_LONG_MAX))
348 overflow = 1;
349 #endif
350
351 if (overflow)
352 {
353 __set_errno (ERANGE);
354 #if UNSIGNED
355 return STRTOL_ULONG_MAX;
356 #else
357 return negative ? STRTOL_LONG_MIN : STRTOL_LONG_MAX;
358 #endif
359 }
360
361 /* Return the result of the appropriate sign. */
362 return negative ? -i : i;
363
364 noconv:
365 /* We must handle a special case here: the base is 0 or 16 and the
366 first two characters are '0' and 'x', but the rest are no
367 hexadecimal digits. This is no error case. We return 0 and
368 ENDPTR points to the 'x'. */
369 if (endptr != NULL)
370 {
371 if (save - nptr >= 2 && TOUPPER (save[-1]) == L_('X')
372 && save[-2] == L_('0'))
373 *endptr = (STRING_TYPE *) &save[-1];
374 else
375 /* There was no number to convert. */
376 *endptr = (STRING_TYPE *) nptr;
377 }
378
379 return 0L;
380 }
381
382 /* External user entry point. */
383
384
385 INT
386 #ifdef weak_function
387 weak_function
388 #endif
strtol(const STRING_TYPE * nptr,STRING_TYPE ** endptr,int base LOCALE_PARAM_PROTO)389 strtol (const STRING_TYPE *nptr, STRING_TYPE **endptr,
390 int base LOCALE_PARAM_PROTO)
391 {
392 return INTERNAL (strtol) (nptr, endptr, base, 0 LOCALE_PARAM);
393 }
394