mirror of
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94a749f69a
Patch by Szymon Siwek <sls@poczta.wp.pl>.
810 lines
22 KiB
C
810 lines
22 KiB
C
/* Copyright (C) 1991-1993,1995-2001,2003,2004,2006, 2007
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Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, write to the Free
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Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
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02111-1307 USA. */
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#include <assert.h>
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#include <limits.h>
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#include <stdio.h>
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#include <stdio_ext.h>
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#include <stdlib.h>
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#include <string.h>
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#include <time.h>
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#include <unistd.h>
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#include <sys/stat.h>
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#define NOID
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#include <timezone/tzfile.h>
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int __use_tzfile;
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static dev_t tzfile_dev;
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static ino64_t tzfile_ino;
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static time_t tzfile_mtime;
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struct ttinfo
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{
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long int offset; /* Seconds east of GMT. */
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unsigned char isdst; /* Used to set tm_isdst. */
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unsigned char idx; /* Index into `zone_names'. */
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unsigned char isstd; /* Transition times are in standard time. */
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unsigned char isgmt; /* Transition times are in GMT. */
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};
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struct leap
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{
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time_t transition; /* Time the transition takes effect. */
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long int change; /* Seconds of correction to apply. */
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};
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static void compute_tzname_max (size_t) internal_function;
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static size_t num_transitions;
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libc_freeres_ptr (static time_t *transitions);
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static unsigned char *type_idxs;
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static size_t num_types;
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static struct ttinfo *types;
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static char *zone_names;
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static long int rule_stdoff;
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static long int rule_dstoff;
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static size_t num_leaps;
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static struct leap *leaps;
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static char *tzspec;
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#include <endian.h>
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#include <byteswap.h>
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/* Decode the four bytes at PTR as a signed integer in network byte order. */
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static inline int
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__attribute ((always_inline))
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decode (const void *ptr)
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{
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if (BYTE_ORDER == BIG_ENDIAN && sizeof (int) == 4)
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return *(const int *) ptr;
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if (sizeof (int) == 4)
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return bswap_32 (*(const int *) ptr);
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const unsigned char *p = ptr;
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int result = *p & (1 << (CHAR_BIT - 1)) ? ~0 : 0;
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result = (result << 8) | *p++;
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result = (result << 8) | *p++;
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result = (result << 8) | *p++;
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result = (result << 8) | *p++;
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return result;
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}
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static inline int64_t
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__attribute ((always_inline))
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decode64 (const void *ptr)
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{
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if ((BYTE_ORDER == BIG_ENDIAN))
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return *(const int64_t *) ptr;
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return bswap_64 (*(const int64_t *) ptr);
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}
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void
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__tzfile_read (const char *file, size_t extra, char **extrap)
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{
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static const char default_tzdir[] = TZDIR;
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size_t num_isstd, num_isgmt;
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register FILE *f;
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struct tzhead tzhead;
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size_t chars;
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register size_t i;
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size_t total_size;
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size_t types_idx;
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size_t leaps_idx;
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int was_using_tzfile = __use_tzfile;
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int trans_width = 4;
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size_t tzspec_len;
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if (sizeof (time_t) != 4 && sizeof (time_t) != 8)
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abort ();
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__use_tzfile = 0;
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if (file == NULL)
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/* No user specification; use the site-wide default. */
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file = TZDEFAULT;
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else if (*file == '\0')
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/* User specified the empty string; use UTC with no leap seconds. */
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goto ret_free_transitions;
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else
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{
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/* We must not allow to read an arbitrary file in a setuid
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program. So we fail for any file which is not in the
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directory hierachy starting at TZDIR
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and which is not the system wide default TZDEFAULT. */
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if (__libc_enable_secure
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&& ((*file == '/'
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&& memcmp (file, TZDEFAULT, sizeof TZDEFAULT)
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&& memcmp (file, default_tzdir, sizeof (default_tzdir) - 1))
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|| strstr (file, "../") != NULL))
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/* This test is certainly a bit too restrictive but it should
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catch all critical cases. */
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goto ret_free_transitions;
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}
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if (*file != '/')
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{
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const char *tzdir;
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unsigned int len, tzdir_len;
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char *new, *tmp;
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tzdir = getenv ("TZDIR");
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if (tzdir == NULL || *tzdir == '\0')
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{
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tzdir = default_tzdir;
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tzdir_len = sizeof (default_tzdir) - 1;
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}
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else
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tzdir_len = strlen (tzdir);
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len = strlen (file) + 1;
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new = (char *) __alloca (tzdir_len + 1 + len);
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tmp = __mempcpy (new, tzdir, tzdir_len);
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*tmp++ = '/';
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memcpy (tmp, file, len);
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file = new;
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}
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/* If we were already using tzfile, check whether the file changed. */
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struct stat64 st;
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if (was_using_tzfile
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&& stat64 (file, &st) == 0
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&& tzfile_ino == st.st_ino && tzfile_dev == st.st_dev
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&& tzfile_mtime == st.st_mtime)
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{
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/* Nothing to do. */
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__use_tzfile = 1;
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return;
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}
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/* Note the file is opened with cancellation in the I/O functions
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disabled. */
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f = fopen (file, "rc");
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if (f == NULL)
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goto ret_free_transitions;
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/* Get information about the file we are actually using. */
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if (fstat64 (fileno (f), &st) != 0)
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{
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fclose (f);
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goto ret_free_transitions;
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}
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free ((void *) transitions);
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transitions = NULL;
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/* Remember the inode and device number and modification time. */
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tzfile_dev = st.st_dev;
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tzfile_ino = st.st_ino;
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tzfile_mtime = st.st_mtime;
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/* No threads reading this stream. */
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__fsetlocking (f, FSETLOCKING_BYCALLER);
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read_again:
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if (__builtin_expect (fread_unlocked ((void *) &tzhead, sizeof (tzhead),
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1, f) != 1, 0)
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|| memcmp (tzhead.tzh_magic, TZ_MAGIC, sizeof (tzhead.tzh_magic)) != 0)
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goto lose;
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num_transitions = (size_t) decode (tzhead.tzh_timecnt);
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num_types = (size_t) decode (tzhead.tzh_typecnt);
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chars = (size_t) decode (tzhead.tzh_charcnt);
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num_leaps = (size_t) decode (tzhead.tzh_leapcnt);
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num_isstd = (size_t) decode (tzhead.tzh_ttisstdcnt);
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num_isgmt = (size_t) decode (tzhead.tzh_ttisgmtcnt);
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/* For platforms with 64-bit time_t we use the new format if available. */
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if (sizeof (time_t) == 8 && trans_width == 4
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&& tzhead.tzh_version[0] != '\0')
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{
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/* We use the 8-byte format. */
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trans_width = 8;
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/* Position the stream before the second header. */
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size_t to_skip = (num_transitions * (4 + 1)
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+ num_types * 6
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+ chars
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+ num_leaps * 8
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+ num_isstd
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+ num_isgmt);
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if (fseek (f, to_skip, SEEK_CUR) != 0)
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goto lose;
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goto read_again;
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}
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total_size = num_transitions * (sizeof (time_t) + 1);
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total_size = ((total_size + __alignof__ (struct ttinfo) - 1)
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& ~(__alignof__ (struct ttinfo) - 1));
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types_idx = total_size;
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total_size += num_types * sizeof (struct ttinfo) + chars;
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total_size = ((total_size + __alignof__ (struct leap) - 1)
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& ~(__alignof__ (struct leap) - 1));
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leaps_idx = total_size;
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total_size += num_leaps * sizeof (struct leap);
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tzspec_len = (sizeof (time_t) == 8 && trans_width == 8
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? st.st_size - (ftello (f)
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+ num_transitions * (8 + 1)
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+ num_types * 6
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+ chars
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+ num_leaps * 8
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+ num_isstd
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+ num_isgmt) - 1 : 0);
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/* Allocate enough memory including the extra block requested by the
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caller. */
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transitions = (time_t *) malloc (total_size + tzspec_len + extra);
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if (transitions == NULL)
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goto lose;
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type_idxs = (unsigned char *) transitions + (num_transitions
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* sizeof (time_t));
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types = (struct ttinfo *) ((char *) transitions + types_idx);
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zone_names = (char *) types + num_types * sizeof (struct ttinfo);
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leaps = (struct leap *) ((char *) transitions + leaps_idx);
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if (sizeof (time_t) == 8 && trans_width == 8)
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tzspec = (char *) leaps + num_leaps * sizeof (struct leap) + extra;
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else
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tzspec = NULL;
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if (extra > 0)
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*extrap = (char *) &leaps[num_leaps];
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if (sizeof (time_t) == 4 || __builtin_expect (trans_width == 8, 1))
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{
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if (__builtin_expect (fread_unlocked (transitions, trans_width + 1,
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num_transitions, f)
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!= num_transitions, 0))
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goto lose;
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}
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else
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{
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if (__builtin_expect (fread_unlocked (transitions, 4, num_transitions, f)
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!= num_transitions, 0)
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|| __builtin_expect (fread_unlocked (type_idxs, 1, num_transitions,
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f) != num_transitions, 0))
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goto lose;
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}
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/* Check for bogus indices in the data file, so we can hereafter
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safely use type_idxs[T] as indices into `types' and never crash. */
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for (i = 0; i < num_transitions; ++i)
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if (__builtin_expect (type_idxs[i] >= num_types, 0))
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goto lose;
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if ((BYTE_ORDER != BIG_ENDIAN && (sizeof (time_t) == 4 || trans_width == 4))
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|| (BYTE_ORDER == BIG_ENDIAN && sizeof (time_t) == 8
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&& trans_width == 4))
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{
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/* Decode the transition times, stored as 4-byte integers in
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network (big-endian) byte order. We work from the end of
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the array so as not to clobber the next element to be
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processed when sizeof (time_t) > 4. */
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i = num_transitions;
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while (i-- > 0)
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transitions[i] = decode ((char *) transitions + i * 4);
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}
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else if (BYTE_ORDER != BIG_ENDIAN && sizeof (time_t) == 8)
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{
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/* Decode the transition times, stored as 8-byte integers in
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network (big-endian) byte order. */
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for (i = 0; i < num_transitions; ++i)
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transitions[i] = decode64 ((char *) transitions + i * 8);
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}
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for (i = 0; i < num_types; ++i)
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{
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unsigned char x[4];
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int c;
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if (__builtin_expect (fread_unlocked (x, 1, sizeof (x), f) != sizeof (x),
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0))
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goto lose;
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c = getc_unlocked (f);
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if (__builtin_expect ((unsigned int) c > 1u, 0))
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goto lose;
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types[i].isdst = c;
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c = getc_unlocked (f);
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if (__builtin_expect ((size_t) c > chars, 0))
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/* Bogus index in data file. */
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goto lose;
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types[i].idx = c;
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types[i].offset = (long int) decode (x);
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}
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if (__builtin_expect (fread_unlocked (zone_names, 1, chars, f) != chars, 0))
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goto lose;
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for (i = 0; i < num_leaps; ++i)
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{
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unsigned char x[8];
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if (__builtin_expect (fread_unlocked (x, 1, trans_width, f)
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!= trans_width, 0))
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goto lose;
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if (sizeof (time_t) == 4 || trans_width == 4)
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leaps[i].transition = (time_t) decode (x);
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else
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leaps[i].transition = (time_t) decode64 (x);
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if (__builtin_expect (fread_unlocked (x, 1, 4, f) != 4, 0))
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goto lose;
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leaps[i].change = (long int) decode (x);
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}
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for (i = 0; i < num_isstd; ++i)
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{
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int c = getc_unlocked (f);
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if (__builtin_expect (c == EOF, 0))
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goto lose;
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types[i].isstd = c != 0;
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}
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while (i < num_types)
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types[i++].isstd = 0;
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for (i = 0; i < num_isgmt; ++i)
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{
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int c = getc_unlocked (f);
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if (__builtin_expect (c == EOF, 0))
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goto lose;
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types[i].isgmt = c != 0;
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}
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while (i < num_types)
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types[i++].isgmt = 0;
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/* Read the POSIX TZ-style information if possible. */
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if (sizeof (time_t) == 8 && tzspec != NULL)
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{
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/* Skip over the newline first. */
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if (getc_unlocked (f) != '\n'
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|| (fread_unlocked (tzspec, 1, tzspec_len - 1, f)
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!= tzspec_len - 1))
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tzspec = NULL;
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else
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tzspec[tzspec_len - 1] = '\0';
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}
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else if (sizeof (time_t) == 4 && tzhead.tzh_version[0] != '\0')
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{
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/* Get the TZ string. */
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if (__builtin_expect (fread_unlocked ((void *) &tzhead, sizeof (tzhead),
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1, f) != 1, 0)
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|| (memcmp (tzhead.tzh_magic, TZ_MAGIC, sizeof (tzhead.tzh_magic))
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!= 0))
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goto lose;
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size_t num_transitions2 = (size_t) decode (tzhead.tzh_timecnt);
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size_t num_types2 = (size_t) decode (tzhead.tzh_typecnt);
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size_t chars2 = (size_t) decode (tzhead.tzh_charcnt);
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size_t num_leaps2 = (size_t) decode (tzhead.tzh_leapcnt);
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size_t num_isstd2 = (size_t) decode (tzhead.tzh_ttisstdcnt);
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size_t num_isgmt2 = (size_t) decode (tzhead.tzh_ttisgmtcnt);
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/* Position the stream before the second header. */
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size_t to_skip = (num_transitions2 * (8 + 1)
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+ num_types2 * 6
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+ chars2
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+ num_leaps2 * 12
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+ num_isstd2
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+ num_isgmt2);
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off_t off;
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if (fseek (f, to_skip, SEEK_CUR) != 0
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|| (off = ftello (f)) < 0
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|| st.st_size < off + 2)
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goto lose;
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tzspec_len = st.st_size - off - 1;
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char *tzstr = alloca (tzspec_len);
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if (getc_unlocked (f) != '\n'
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|| (fread_unlocked (tzstr, 1, tzspec_len - 1, f) != tzspec_len - 1))
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goto lose;
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tzstr[tzspec_len - 1] = '\0';
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tzspec = __tzstring (tzstr);
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}
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fclose (f);
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/* First "register" all timezone names. */
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for (i = 0; i < num_types; ++i)
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(void) __tzstring (&zone_names[types[i].idx]);
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/* Find the standard and daylight time offsets used by the rule file.
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We choose the offsets in the types of each flavor that are
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transitioned to earliest in time. */
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__tzname[0] = NULL;
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__tzname[1] = NULL;
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for (i = num_transitions; i > 0; )
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{
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int type = type_idxs[--i];
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int dst = types[type].isdst;
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if (__tzname[dst] == NULL)
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{
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int idx = types[type].idx;
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__tzname[dst] = __tzstring (&zone_names[idx]);
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if (__tzname[1 - dst] != NULL)
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break;
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}
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}
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if (__tzname[0] == NULL)
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{
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/* This should only happen if there are no transition rules.
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In this case there should be only one single type. */
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assert (num_types == 1);
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__tzname[0] = __tzstring (zone_names);
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}
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if (__tzname[1] == NULL)
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__tzname[1] = __tzname[0];
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compute_tzname_max (chars);
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if (num_transitions == 0)
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/* Use the first rule (which should also be the only one). */
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rule_stdoff = rule_dstoff = types[0].offset;
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else
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{
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int stdoff_set = 0, dstoff_set = 0;
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rule_stdoff = rule_dstoff = 0;
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i = num_transitions - 1;
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do
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{
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if (!stdoff_set && !types[type_idxs[i]].isdst)
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{
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stdoff_set = 1;
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rule_stdoff = types[type_idxs[i]].offset;
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}
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else if (!dstoff_set && types[type_idxs[i]].isdst)
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{
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dstoff_set = 1;
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rule_dstoff = types[type_idxs[i]].offset;
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}
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if (stdoff_set && dstoff_set)
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break;
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}
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while (i-- > 0);
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if (!dstoff_set)
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rule_dstoff = rule_stdoff;
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}
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__daylight = rule_stdoff != rule_dstoff;
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__timezone = -rule_stdoff;
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||
|
||
__use_tzfile = 1;
|
||
return;
|
||
|
||
lose:
|
||
fclose (f);
|
||
ret_free_transitions:
|
||
free ((void *) transitions);
|
||
transitions = NULL;
|
||
}
|
||
|
||
/* The user specified a hand-made timezone, but not its DST rules.
|
||
We will use the names and offsets from the user, and the rules
|
||
from the TZDEFRULES file. */
|
||
|
||
void
|
||
__tzfile_default (const char *std, const char *dst,
|
||
long int stdoff, long int dstoff)
|
||
{
|
||
size_t stdlen = strlen (std) + 1;
|
||
size_t dstlen = strlen (dst) + 1;
|
||
size_t i;
|
||
int isdst;
|
||
char *cp;
|
||
|
||
__tzfile_read (TZDEFRULES, stdlen + dstlen, &cp);
|
||
if (!__use_tzfile)
|
||
return;
|
||
|
||
if (num_types < 2)
|
||
{
|
||
__use_tzfile = 0;
|
||
return;
|
||
}
|
||
|
||
/* Ignore the zone names read from the file and use the given ones
|
||
instead. */
|
||
__mempcpy (__mempcpy (cp, std, stdlen), dst, dstlen);
|
||
zone_names = cp;
|
||
|
||
/* Now there are only two zones, regardless of what the file contained. */
|
||
num_types = 2;
|
||
|
||
/* Now correct the transition times for the user-specified standard and
|
||
daylight offsets from GMT. */
|
||
isdst = 0;
|
||
for (i = 0; i < num_transitions; ++i)
|
||
{
|
||
struct ttinfo *trans_type = &types[type_idxs[i]];
|
||
|
||
/* We will use only types 0 (standard) and 1 (daylight).
|
||
Fix up this transition to point to whichever matches
|
||
the flavor of its original type. */
|
||
type_idxs[i] = trans_type->isdst;
|
||
|
||
if (trans_type->isgmt)
|
||
/* The transition time is in GMT. No correction to apply. */ ;
|
||
else if (isdst && !trans_type->isstd)
|
||
/* The type says this transition is in "local wall clock time", and
|
||
wall clock time as of the previous transition was DST. Correct
|
||
for the difference between the rule's DST offset and the user's
|
||
DST offset. */
|
||
transitions[i] += dstoff - rule_dstoff;
|
||
else
|
||
/* This transition is in "local wall clock time", and wall clock
|
||
time as of this iteration is non-DST. Correct for the
|
||
difference between the rule's standard offset and the user's
|
||
standard offset. */
|
||
transitions[i] += stdoff - rule_stdoff;
|
||
|
||
/* The DST state of "local wall clock time" for the next iteration is
|
||
as specified by this transition. */
|
||
isdst = trans_type->isdst;
|
||
}
|
||
|
||
/* Now that we adjusted the transitions to the requested offsets,
|
||
reset the rule_stdoff and rule_dstoff values appropriately. They
|
||
are used elsewhere. */
|
||
rule_stdoff = stdoff;
|
||
rule_dstoff = dstoff;
|
||
|
||
/* Reset types 0 and 1 to describe the user's settings. */
|
||
types[0].idx = 0;
|
||
types[0].offset = stdoff;
|
||
types[0].isdst = 0;
|
||
types[1].idx = stdlen;
|
||
types[1].offset = dstoff;
|
||
types[1].isdst = 1;
|
||
|
||
/* Reset the zone names to point to the user's names. */
|
||
__tzname[0] = (char *) std;
|
||
__tzname[1] = (char *) dst;
|
||
|
||
/* Set the timezone. */
|
||
__timezone = -types[0].offset;
|
||
|
||
compute_tzname_max (stdlen + dstlen);
|
||
}
|
||
|
||
void
|
||
__tzfile_compute (time_t timer, int use_localtime,
|
||
long int *leap_correct, int *leap_hit,
|
||
struct tm *tp)
|
||
{
|
||
register size_t i;
|
||
|
||
if (use_localtime)
|
||
{
|
||
__tzname[0] = NULL;
|
||
__tzname[1] = NULL;
|
||
|
||
if (__builtin_expect (num_transitions == 0 || timer < transitions[0], 0))
|
||
{
|
||
/* TIMER is before any transition (or there are no transitions).
|
||
Choose the first non-DST type
|
||
(or the first if they're all DST types). */
|
||
i = 0;
|
||
while (i < num_types && types[i].isdst)
|
||
{
|
||
if (__tzname[1] == NULL)
|
||
__tzname[1] = __tzstring (&zone_names[types[i].idx]);
|
||
|
||
++i;
|
||
}
|
||
|
||
if (i == num_types)
|
||
i = 0;
|
||
__tzname[0] = __tzstring (&zone_names[types[i].idx]);
|
||
if (__tzname[1] == NULL)
|
||
{
|
||
size_t j = i;
|
||
while (j < num_types)
|
||
if (types[j].isdst)
|
||
{
|
||
__tzname[1] = __tzstring (&zone_names[types[j].idx]);
|
||
break;
|
||
}
|
||
else
|
||
++j;
|
||
}
|
||
}
|
||
else if (__builtin_expect (timer >= transitions[num_transitions - 1], 0))
|
||
{
|
||
if (__builtin_expect (tzspec == NULL, 0))
|
||
{
|
||
use_last:
|
||
i = num_transitions;
|
||
goto found;
|
||
}
|
||
|
||
/* Parse the POSIX TZ-style string. */
|
||
__tzset_parse_tz (tzspec);
|
||
|
||
/* Convert to broken down structure. If this fails do not
|
||
use the string. */
|
||
if (__builtin_expect (! __offtime (&timer, 0, tp), 0))
|
||
goto use_last;
|
||
|
||
/* Use the rules from the TZ string to compute the change. */
|
||
__tz_compute (timer, tp, 1);
|
||
|
||
/* If tzspec comes from posixrules loaded by __tzfile_default,
|
||
override the STD and DST zone names with the ones user
|
||
requested in TZ envvar. */
|
||
if (__builtin_expect (zone_names == (char *) &leaps[num_leaps], 0))
|
||
{
|
||
assert (num_types == 2);
|
||
__tzname[0] = __tzstring (zone_names);
|
||
__tzname[1] = __tzstring (&zone_names[strlen (zone_names) + 1]);
|
||
}
|
||
|
||
*leap_correct = 0L;
|
||
*leap_hit = 0;
|
||
return;
|
||
}
|
||
else
|
||
{
|
||
/* Find the first transition after TIMER, and
|
||
then pick the type of the transition before it. */
|
||
size_t lo = 0;
|
||
size_t hi = num_transitions - 1;
|
||
/* Assume that DST is changing twice a year and guess initial
|
||
search spot from it.
|
||
Half of a gregorian year has on average 365.2425 * 86400 / 2
|
||
= 15778476 seconds. */
|
||
i = (transitions[num_transitions - 1] - timer) / 15778476;
|
||
if (i < num_transitions)
|
||
{
|
||
i = num_transitions - 1 - i;
|
||
if (timer < transitions[i])
|
||
{
|
||
if (i < 10 || timer >= transitions[i - 10])
|
||
{
|
||
/* Linear search. */
|
||
while (timer < transitions[i - 1])
|
||
--i;
|
||
goto found;
|
||
}
|
||
hi = i - 10;
|
||
}
|
||
else
|
||
{
|
||
if (i + 10 >= num_transitions || timer < transitions[i + 10])
|
||
{
|
||
/* Linear search. */
|
||
while (timer >= transitions[i])
|
||
++i;
|
||
goto found;
|
||
}
|
||
lo = i + 10;
|
||
}
|
||
}
|
||
|
||
/* Binary search. */
|
||
/* assert (timer >= transitions[lo] && timer < transitions[hi]); */
|
||
while (lo + 1 < hi)
|
||
{
|
||
i = (lo + hi) / 2;
|
||
if (timer < transitions[i])
|
||
hi = i;
|
||
else
|
||
lo = i;
|
||
}
|
||
i = hi;
|
||
|
||
found:
|
||
/* assert (timer >= transitions[i - 1]
|
||
&& (i == num_transitions || timer < transitions[i])); */
|
||
__tzname[types[type_idxs[i - 1]].isdst]
|
||
= __tzstring (&zone_names[types[type_idxs[i - 1]].idx]);
|
||
size_t j = i;
|
||
while (j < num_transitions)
|
||
{
|
||
int type = type_idxs[j];
|
||
int dst = types[type].isdst;
|
||
int idx = types[type].idx;
|
||
|
||
if (__tzname[dst] == NULL)
|
||
{
|
||
__tzname[dst] = __tzstring (&zone_names[idx]);
|
||
|
||
if (__tzname[1 - dst] != NULL)
|
||
break;
|
||
}
|
||
|
||
++j;
|
||
}
|
||
|
||
if (__builtin_expect (__tzname[0] == NULL, 0))
|
||
__tzname[0] = __tzname[1];
|
||
|
||
i = type_idxs[i - 1];
|
||
}
|
||
|
||
struct ttinfo *info = &types[i];
|
||
__daylight = rule_stdoff != rule_dstoff;
|
||
__timezone = -rule_stdoff;
|
||
|
||
if (__tzname[0] == NULL)
|
||
{
|
||
/* This should only happen if there are no transition rules.
|
||
In this case there should be only one single type. */
|
||
assert (num_types == 1);
|
||
__tzname[0] = __tzstring (zone_names);
|
||
}
|
||
if (__tzname[1] == NULL)
|
||
/* There is no daylight saving time. */
|
||
__tzname[1] = __tzname[0];
|
||
tp->tm_isdst = info->isdst;
|
||
assert (strcmp (&zone_names[info->idx], __tzname[tp->tm_isdst]) == 0);
|
||
tp->tm_zone = __tzname[tp->tm_isdst];
|
||
tp->tm_gmtoff = info->offset;
|
||
}
|
||
|
||
*leap_correct = 0L;
|
||
*leap_hit = 0;
|
||
|
||
/* Find the last leap second correction transition time before TIMER. */
|
||
i = num_leaps;
|
||
do
|
||
if (i-- == 0)
|
||
return;
|
||
while (timer < leaps[i].transition);
|
||
|
||
/* Apply its correction. */
|
||
*leap_correct = leaps[i].change;
|
||
|
||
if (timer == leaps[i].transition && /* Exactly at the transition time. */
|
||
((i == 0 && leaps[i].change > 0) ||
|
||
leaps[i].change > leaps[i - 1].change))
|
||
{
|
||
*leap_hit = 1;
|
||
while (i > 0
|
||
&& leaps[i].transition == leaps[i - 1].transition + 1
|
||
&& leaps[i].change == leaps[i - 1].change + 1)
|
||
{
|
||
++*leap_hit;
|
||
--i;
|
||
}
|
||
}
|
||
}
|
||
|
||
static void
|
||
internal_function
|
||
compute_tzname_max (size_t chars)
|
||
{
|
||
const char *p;
|
||
|
||
p = zone_names;
|
||
do
|
||
{
|
||
const char *start = p;
|
||
while (*p != '\0')
|
||
++p;
|
||
if ((size_t) (p - start) > __tzname_cur_max)
|
||
__tzname_cur_max = p - start;
|
||
}
|
||
while (++p < &zone_names[chars]);
|
||
}
|