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git.proxmox.com Git - wasi-libc.git/blob - libc-top-half/musl/src/time/__tz.c
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6 #ifdef __wasilibc_unmodified_upstream // timezone data
12 #ifdef __wasilibc_unmodified_upstream // timezone data
15 char *__tzname
[2] = { 0, 0 };
17 weak_alias(__timezone
, timezone
);
18 weak_alias(__daylight
, daylight
);
19 weak_alias(__tzname
, tzname
);
21 static char std_name
[TZNAME_MAX
+1];
22 static char dst_name
[TZNAME_MAX
+1];
24 const char __utc
[] = "UTC";
26 #ifdef __wasilibc_unmodified_upstream // timezone data
28 static int r0
[5], r1
[5];
30 static const unsigned char *zi
, *trans
, *index
, *types
, *abbrevs
, *abbrevs_end
;
31 static size_t map_size
;
33 static char old_tz_buf
[32];
34 static char *old_tz
= old_tz_buf
;
35 static size_t old_tz_size
= sizeof old_tz_buf
;
37 static volatile int lock
[1];
39 static int getint(const char **p
)
42 for (x
=0; **p
-'0'<10U; (*p
)++) x
= **p
-'0' + 10*x
;
46 static int getoff(const char **p
)
52 } else if (**p
== '+') {
55 int off
= 3600*getint(p
);
64 return neg
? -off
: off
;
67 static void getrule(const char **p
, int rule
[5])
69 int r
= rule
[0] = **p
;
76 ++*p
; rule
[1] = getint(p
);
77 ++*p
; rule
[2] = getint(p
);
78 ++*p
; rule
[3] = getint(p
);
89 static void getname(char *d
, const char **p
)
94 for (i
=0; (*p
)[i
] && (*p
)[i
]!='>'; i
++)
95 if (i
<TZNAME_MAX
) d
[i
] = (*p
)[i
];
98 for (i
=0; ((*p
)[i
]|32)-'a'<26U; i
++)
99 if (i
<TZNAME_MAX
) d
[i
] = (*p
)[i
];
102 d
[i
<TZNAME_MAX
?i
:TZNAME_MAX
] = 0;
105 #define VEC(...) ((const unsigned char[]){__VA_ARGS__})
107 static uint32_t zi_read32(const unsigned char *z
)
109 return (unsigned)z
[0]<<24 | z
[1]<<16 | z
[2]<<8 | z
[3];
112 static size_t zi_dotprod(const unsigned char *z
, const unsigned char *v
, size_t n
)
116 for (y
=0; n
; n
--, z
+=4, v
++) {
123 static void do_tzset()
125 char buf
[NAME_MAX
+25], *pathname
=buf
+24;
126 const char *try, *s
, *p
;
127 const unsigned char *map
= 0;
129 static const char search
[] =
130 "/usr/share/zoneinfo/\0/share/zoneinfo/\0/etc/zoneinfo/\0";
133 if (!s
) s
= "/etc/localtime";
136 if (old_tz
&& !strcmp(s
, old_tz
)) return;
138 for (i
=0; i
<5; i
++) r0
[i
] = r1
[i
] = 0;
140 if (zi
) __munmap((void *)zi
, map_size
);
142 /* Cache the old value of TZ to check if it has changed. Avoid
143 * free so as not to pull it into static programs. Growth
144 * strategy makes it so free would have minimal benefit anyway. */
146 if (i
> PATH_MAX
+1) s
= __utc
, i
= 3;
147 if (i
>= old_tz_size
) {
149 if (i
>= old_tz_size
) old_tz_size
= i
+1;
150 if (old_tz_size
> PATH_MAX
+2) old_tz_size
= PATH_MAX
+2;
151 old_tz
= malloc(old_tz_size
);
153 if (old_tz
) memcpy(old_tz
, s
, i
+1);
155 /* Non-suid can use an absolute tzfile pathname or a relative
156 * pathame beginning with "."; in secure mode, only the
157 * standard path will be searched. */
158 if (*s
== ':' || ((p
=strchr(s
, '/')) && !memchr(s
, ',', p
-s
))) {
160 if (*s
== '/' || *s
== '.') {
161 if (!libc
.secure
|| !strcmp(s
, "/etc/localtime"))
162 map
= __map_file(s
, &map_size
);
164 size_t l
= strlen(s
);
165 if (l
<= NAME_MAX
&& !strchr(s
, '.')) {
166 memcpy(pathname
, s
, l
+1);
168 for (try=search
; !map
&& *try; try+=l
+1) {
170 memcpy(pathname
-l
, try, l
);
171 map
= __map_file(pathname
-l
, &map_size
);
177 if (map
&& (map_size
< 44 || memcmp(map
, "TZif", 4))) {
178 __munmap((void *)map
, map_size
);
186 if (sizeof(time_t) > 4 && map
[4]=='2') {
187 size_t skip
= zi_dotprod(zi
+20, VEC(1,1,8,5,6,1), 6);
188 trans
= zi
+skip
+44+44;
193 index
= trans
+ (zi_read32(trans
-12) << scale
);
194 types
= index
+ zi_read32(trans
-12);
195 abbrevs
= types
+ 6*zi_read32(trans
-8);
196 abbrevs_end
= abbrevs
+ zi_read32(trans
-4);
197 if (zi
[map_size
-1] == '\n') {
198 for (s
= (const char *)zi
+map_size
-2; *s
!='\n'; s
--);
201 const unsigned char *p
;
202 __tzname
[0] = __tzname
[1] = 0;
203 __daylight
= __timezone
= dst_off
= 0;
204 for (p
=types
; p
<abbrevs
; p
+=6) {
205 if (!p
[4] && !__tzname
[0]) {
206 __tzname
[0] = (char *)abbrevs
+ p
[5];
207 __timezone
= -zi_read32(p
);
209 if (p
[4] && !__tzname
[1]) {
210 __tzname
[1] = (char *)abbrevs
+ p
[5];
211 dst_off
= -zi_read32(p
);
215 if (!__tzname
[0]) __tzname
[0] = __tzname
[1];
216 if (!__tzname
[0]) __tzname
[0] = (char *)__utc
;
218 __tzname
[1] = __tzname
[0];
219 dst_off
= __timezone
;
226 getname(std_name
, &s
);
227 __tzname
[0] = std_name
;
228 __timezone
= getoff(&s
);
229 getname(dst_name
, &s
);
230 __tzname
[1] = dst_name
;
233 if (*s
== '+' || *s
=='-' || *s
-'0'<10U)
234 dst_off
= getoff(&s
);
236 dst_off
= __timezone
- 3600;
239 dst_off
= __timezone
;
242 if (*s
== ',') s
++, getrule(&s
, r0
);
243 if (*s
== ',') s
++, getrule(&s
, r1
);
246 /* Search zoneinfo rules to find the one that applies to the given time,
247 * and determine alternate opposite-DST-status rule that may be needed. */
249 static size_t scan_trans(long long t
, int local
, size_t *alt
)
251 int scale
= 3 - (trans
== zi
+44);
255 size_t a
= 0, n
= (index
-trans
)>>scale
, m
;
262 /* Binary search for 'most-recent rule before t'. */
265 x
= zi_read32(trans
+ (m
<<scale
));
266 if (scale
== 3) x
= x
<<32 | zi_read32(trans
+ (m
<<scale
) + 4);
268 if (local
) off
= (int32_t)zi_read32(types
+ 6 * index
[m
-1]);
269 if (t
- off
< (int64_t)x
) {
277 /* First and last entry are special. First means to use lowest-index
278 * non-DST type. Last means to apply POSIX-style rule if available. */
279 n
= (index
-trans
)>>scale
;
280 if (a
== n
-1) return -1;
282 x
= zi_read32(trans
+ (a
<<scale
));
283 if (scale
== 3) x
= x
<<32 | zi_read32(trans
+ (a
<<scale
) + 4);
285 if (local
) off
= (int32_t)zi_read32(types
+ 6 * index
[a
-1]);
286 if (t
- off
< (int64_t)x
) {
287 for (a
=0; a
<(abbrevs
-types
)/6; a
++) {
288 if (types
[6*a
+4] != types
[4]) break;
290 if (a
== (abbrevs
-types
)/6) a
= 0;
301 /* Try to find a neighboring opposite-DST-status rule. */
303 if (a
&& types
[6*index
[a
-1]+4] != types
[6*index
[a
]+4])
305 else if (a
+1<n
&& types
[6*index
[a
+1]+4] != types
[6*index
[a
]+4])
314 static int days_in_month(int m
, int is_leap
)
316 if (m
==2) return 28+is_leap
;
317 else return 30+((0xad5>>(m
-1))&1);
320 /* Convert a POSIX DST rule plus year to seconds since epoch. */
322 static long long rule_to_secs(const int *rule
, int year
)
325 long long t
= __year_to_secs(year
, &is_leap
);
329 if (rule
[0]=='J' && (x
< 60 || !is_leap
)) x
--;
335 t
+= __month_to_secs(m
-1, is_leap
);
336 int wday
= (int)((t
+ 4*86400) % (7*86400)) / 86400;
338 if (days
< 0) days
+= 7;
339 if (n
== 5 && days
+28 >= days_in_month(m
, is_leap
)) n
= 4;
340 t
+= 86400 * (days
+ 7*(n
-1));
346 /* Determine the time zone in effect for a given time in seconds since the
347 * epoch. It can be given in local or universal time. The results will
348 * indicate whether DST is in effect at the queried time, and will give both
349 * the GMT offset for the active zone/DST rule and the opposite DST. This
350 * enables a caller to efficiently adjust for the case where an explicit
351 * DST specification mismatches what would be in effect at the time. */
353 void __secs_to_zone(long long t
, int local
, int *isdst
, long *offset
, long *oppoff
, const char **zonename
)
360 size_t alt
, i
= scan_trans(t
, local
, &alt
);
362 *isdst
= types
[6*i
+4];
363 *offset
= (int32_t)zi_read32(types
+6*i
);
364 *zonename
= (const char *)abbrevs
+ types
[6*i
+5];
365 if (oppoff
) *oppoff
= (int32_t)zi_read32(types
+6*alt
);
371 if (!__daylight
) goto std
;
373 /* FIXME: may be broken if DST changes right at year boundary?
374 * Also, this could be more efficient.*/
375 long long y
= t
/ 31556952 + 70;
376 while (__year_to_secs(y
, 0) > t
) y
--;
377 while (__year_to_secs(y
+1, 0) < t
) y
++;
379 long long t0
= rule_to_secs(r0
, y
);
380 long long t1
= rule_to_secs(r1
, y
);
387 if (t
>= t0
&& t
< t1
) goto dst
;
390 if (t
>= t1
&& t
< t0
) goto std
;
395 *offset
= -__timezone
;
396 if (oppoff
) *oppoff
= -dst_off
;
397 *zonename
= __tzname
[0];
403 if (oppoff
) *oppoff
= -__timezone
;
404 *zonename
= __tzname
[1];
408 static void __tzset()
415 weak_alias(__tzset
, tzset
);
417 void __secs_to_zone(long long t
, int local
, int *isdst
, int *offset
, long *oppoff
, const char **zonename
)
419 // Minimalist implementation for now.
427 const char *__tm_to_tzname(const struct tm
*tm
)
429 const void *p
= tm
->__tm_zone
;
430 #ifdef __wasilibc_unmodified_upstream // timezone data
433 if (p
!= __utc
&& p
!= __tzname
[0] && p
!= __tzname
[1] &&
434 (!zi
|| (uintptr_t)p
-(uintptr_t)abbrevs
>= abbrevs_end
- abbrevs
))