[Feature][ZXW-33]merge ZXW 0428 version

Change-Id: I11f167edfea428d9fab198ff00ff1364932d1b0b
diff --git a/ap/libc/glibc/glibc-2.23/time/tzfile.c b/ap/libc/glibc/glibc-2.23/time/tzfile.c
new file mode 100644
index 0000000..9049878
--- /dev/null
+++ b/ap/libc/glibc/glibc-2.23/time/tzfile.c
@@ -0,0 +1,857 @@
+/* Copyright (C) 1991-2016 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <assert.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdio_ext.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#include <stdint.h>
+
+#define	NOID
+#include <timezone/tzfile.h>
+
+int __use_tzfile;
+static dev_t tzfile_dev;
+static ino64_t tzfile_ino;
+static time_t tzfile_mtime;
+
+struct ttinfo
+  {
+    long int offset;		/* Seconds east of GMT.  */
+    unsigned char isdst;	/* Used to set tm_isdst.  */
+    unsigned char idx;		/* Index into `zone_names'.  */
+    unsigned char isstd;	/* Transition times are in standard time.  */
+    unsigned char isgmt;	/* Transition times are in GMT.  */
+  };
+
+struct leap
+  {
+    time_t transition;		/* Time the transition takes effect.  */
+    long int change;		/* Seconds of correction to apply.  */
+  };
+
+static void compute_tzname_max (size_t) internal_function;
+
+static size_t num_transitions;
+libc_freeres_ptr (static time_t *transitions);
+static unsigned char *type_idxs;
+static size_t num_types;
+static struct ttinfo *types;
+static char *zone_names;
+static long int rule_stdoff;
+static long int rule_dstoff;
+static size_t num_leaps;
+static struct leap *leaps;
+static char *tzspec;
+
+#include <endian.h>
+#include <byteswap.h>
+
+/* Decode the four bytes at PTR as a signed integer in network byte order.  */
+static inline int
+__attribute ((always_inline))
+decode (const void *ptr)
+{
+  if (BYTE_ORDER == BIG_ENDIAN && sizeof (int) == 4)
+    return *(const int *) ptr;
+  if (sizeof (int) == 4)
+    return bswap_32 (*(const int *) ptr);
+
+  const unsigned char *p = ptr;
+  int result = *p & (1 << (CHAR_BIT - 1)) ? ~0 : 0;
+
+  result = (result << 8) | *p++;
+  result = (result << 8) | *p++;
+  result = (result << 8) | *p++;
+  result = (result << 8) | *p++;
+
+  return result;
+}
+
+
+static inline int64_t
+__attribute ((always_inline))
+decode64 (const void *ptr)
+{
+  if ((BYTE_ORDER == BIG_ENDIAN))
+    return *(const int64_t *) ptr;
+
+  return bswap_64 (*(const int64_t *) ptr);
+}
+
+
+void
+__tzfile_read (const char *file, size_t extra, char **extrap)
+{
+  static const char default_tzdir[] = TZDIR;
+  size_t num_isstd, num_isgmt;
+  FILE *f;
+  struct tzhead tzhead;
+  size_t chars;
+  size_t i;
+  size_t total_size;
+  size_t types_idx;
+  size_t leaps_idx;
+  int was_using_tzfile = __use_tzfile;
+  int trans_width = 4;
+  size_t tzspec_len;
+  char *new = NULL;
+
+  if (sizeof (time_t) != 4 && sizeof (time_t) != 8)
+    abort ();
+
+  __use_tzfile = 0;
+
+  if (file == NULL)
+    /* No user specification; use the site-wide default.  */
+    file = TZDEFAULT;
+  else if (*file == '\0')
+    /* User specified the empty string; use UTC with no leap seconds.  */
+    goto ret_free_transitions;
+  else
+    {
+      /* We must not allow to read an arbitrary file in a setuid
+	 program.  So we fail for any file which is not in the
+	 directory hierachy starting at TZDIR
+	 and which is not the system wide default TZDEFAULT.  */
+      if (__libc_enable_secure
+	  && ((*file == '/'
+	       && memcmp (file, TZDEFAULT, sizeof TZDEFAULT)
+	       && memcmp (file, default_tzdir, sizeof (default_tzdir) - 1))
+	      || strstr (file, "../") != NULL))
+	/* This test is certainly a bit too restrictive but it should
+	   catch all critical cases.  */
+	goto ret_free_transitions;
+    }
+
+  if (*file != '/')
+    {
+      const char *tzdir;
+
+      tzdir = getenv ("TZDIR");
+      if (tzdir == NULL || *tzdir == '\0')
+	tzdir = default_tzdir;
+      if (__asprintf (&new, "%s/%s", tzdir, file) == -1)
+	goto ret_free_transitions;
+      file = new;
+    }
+
+  /* If we were already using tzfile, check whether the file changed.  */
+  struct stat64 st;
+  if (was_using_tzfile
+      && stat64 (file, &st) == 0
+      && tzfile_ino == st.st_ino && tzfile_dev == st.st_dev
+      && tzfile_mtime == st.st_mtime)
+    goto done;  /* Nothing to do.  */
+
+  /* Note the file is opened with cancellation in the I/O functions
+     disabled and if available FD_CLOEXEC set.  */
+  f = fopen (file, "rce");
+  if (f == NULL)
+    goto ret_free_transitions;
+
+  /* Get information about the file we are actually using.  */
+  if (fstat64 (__fileno (f), &st) != 0)
+    {
+      fclose (f);
+      goto ret_free_transitions;
+    }
+
+  free ((void *) transitions);
+  transitions = NULL;
+
+  /* Remember the inode and device number and modification time.  */
+  tzfile_dev = st.st_dev;
+  tzfile_ino = st.st_ino;
+  tzfile_mtime = st.st_mtime;
+
+  /* No threads reading this stream.  */
+  __fsetlocking (f, FSETLOCKING_BYCALLER);
+
+ read_again:
+  if (__builtin_expect (__fread_unlocked ((void *) &tzhead, sizeof (tzhead),
+					  1, f) != 1, 0)
+      || memcmp (tzhead.tzh_magic, TZ_MAGIC, sizeof (tzhead.tzh_magic)) != 0)
+    goto lose;
+
+  num_transitions = (size_t) decode (tzhead.tzh_timecnt);
+  num_types = (size_t) decode (tzhead.tzh_typecnt);
+  chars = (size_t) decode (tzhead.tzh_charcnt);
+  num_leaps = (size_t) decode (tzhead.tzh_leapcnt);
+  num_isstd = (size_t) decode (tzhead.tzh_ttisstdcnt);
+  num_isgmt = (size_t) decode (tzhead.tzh_ttisgmtcnt);
+
+  if (__glibc_unlikely (num_isstd > num_types || num_isgmt > num_types))
+    goto lose;
+
+  /* For platforms with 64-bit time_t we use the new format if available.  */
+  if (sizeof (time_t) == 8 && trans_width == 4
+      && tzhead.tzh_version[0] != '\0')
+    {
+      /* We use the 8-byte format.  */
+      trans_width = 8;
+
+      /* Position the stream before the second header.  */
+      size_t to_skip = (num_transitions * (4 + 1)
+			+ num_types * 6
+			+ chars
+			+ num_leaps * 8
+			+ num_isstd
+			+ num_isgmt);
+      if (fseek (f, to_skip, SEEK_CUR) != 0)
+	goto lose;
+
+      goto read_again;
+    }
+
+  if (__builtin_expect (num_transitions
+			> ((SIZE_MAX - (__alignof__ (struct ttinfo) - 1))
+			   / (sizeof (time_t) + 1)), 0))
+    goto lose;
+  total_size = num_transitions * (sizeof (time_t) + 1);
+  total_size = ((total_size + __alignof__ (struct ttinfo) - 1)
+		& ~(__alignof__ (struct ttinfo) - 1));
+  types_idx = total_size;
+  if (__builtin_expect (num_types
+			> (SIZE_MAX - total_size) / sizeof (struct ttinfo), 0))
+    goto lose;
+  total_size += num_types * sizeof (struct ttinfo);
+  if (__glibc_unlikely (chars > SIZE_MAX - total_size))
+    goto lose;
+  total_size += chars;
+  if (__builtin_expect (__alignof__ (struct leap) - 1
+			> SIZE_MAX - total_size, 0))
+    goto lose;
+  total_size = ((total_size + __alignof__ (struct leap) - 1)
+		& ~(__alignof__ (struct leap) - 1));
+  leaps_idx = total_size;
+  if (__builtin_expect (num_leaps
+			> (SIZE_MAX - total_size) / sizeof (struct leap), 0))
+    goto lose;
+  total_size += num_leaps * sizeof (struct leap);
+  tzspec_len = 0;
+  if (sizeof (time_t) == 8 && trans_width == 8)
+    {
+      off_t rem = st.st_size - __ftello (f);
+      if (__builtin_expect (rem < 0
+			    || (size_t) rem < (num_transitions * (8 + 1)
+					       + num_types * 6
+					       + chars), 0))
+	goto lose;
+      tzspec_len = (size_t) rem - (num_transitions * (8 + 1)
+				   + num_types * 6
+				   + chars);
+      if (__builtin_expect (num_leaps > SIZE_MAX / 12
+			    || tzspec_len < num_leaps * 12, 0))
+	goto lose;
+      tzspec_len -= num_leaps * 12;
+      if (__glibc_unlikely (tzspec_len < num_isstd))
+	goto lose;
+      tzspec_len -= num_isstd;
+      if (__glibc_unlikely (tzspec_len == 0 || tzspec_len - 1 < num_isgmt))
+	goto lose;
+      tzspec_len -= num_isgmt + 1;
+      if (__glibc_unlikely (tzspec_len == 0
+			    || SIZE_MAX - total_size < tzspec_len))
+	goto lose;
+    }
+  if (__glibc_unlikely (SIZE_MAX - total_size - tzspec_len < extra))
+    goto lose;
+
+  /* Allocate enough memory including the extra block requested by the
+     caller.  */
+  transitions = (time_t *) malloc (total_size + tzspec_len + extra);
+  if (transitions == NULL)
+    goto lose;
+
+  type_idxs = (unsigned char *) transitions + (num_transitions
+					       * sizeof (time_t));
+  types = (struct ttinfo *) ((char *) transitions + types_idx);
+  zone_names = (char *) types + num_types * sizeof (struct ttinfo);
+  leaps = (struct leap *) ((char *) transitions + leaps_idx);
+  if (sizeof (time_t) == 8 && trans_width == 8)
+    tzspec = (char *) leaps + num_leaps * sizeof (struct leap) + extra;
+  else
+    tzspec = NULL;
+  if (extra > 0)
+    *extrap = (char *) &leaps[num_leaps];
+
+  if (sizeof (time_t) == 4 || __builtin_expect (trans_width == 8, 1))
+    {
+      if (__builtin_expect (__fread_unlocked (transitions, trans_width + 1,
+					      num_transitions, f)
+			    != num_transitions, 0))
+	goto lose;
+    }
+  else
+    {
+      if (__builtin_expect (__fread_unlocked (transitions, 4,
+					      num_transitions, f)
+			    != num_transitions, 0)
+	  || __builtin_expect (__fread_unlocked (type_idxs, 1, num_transitions,
+						 f) != num_transitions, 0))
+	goto lose;
+    }
+
+  /* Check for bogus indices in the data file, so we can hereafter
+     safely use type_idxs[T] as indices into `types' and never crash.  */
+  for (i = 0; i < num_transitions; ++i)
+    if (__glibc_unlikely (type_idxs[i] >= num_types))
+      goto lose;
+
+  if ((BYTE_ORDER != BIG_ENDIAN && (sizeof (time_t) == 4 || trans_width == 4))
+      || (BYTE_ORDER == BIG_ENDIAN && sizeof (time_t) == 8
+	  && trans_width == 4))
+    {
+      /* Decode the transition times, stored as 4-byte integers in
+	 network (big-endian) byte order.  We work from the end of
+	 the array so as not to clobber the next element to be
+	 processed when sizeof (time_t) > 4.  */
+      i = num_transitions;
+      while (i-- > 0)
+	transitions[i] = decode ((char *) transitions + i * 4);
+    }
+  else if (BYTE_ORDER != BIG_ENDIAN && sizeof (time_t) == 8)
+    {
+      /* Decode the transition times, stored as 8-byte integers in
+	 network (big-endian) byte order.  */
+      for (i = 0; i < num_transitions; ++i)
+	transitions[i] = decode64 ((char *) transitions + i * 8);
+    }
+
+  for (i = 0; i < num_types; ++i)
+    {
+      unsigned char x[4];
+      int c;
+      if (__builtin_expect (__fread_unlocked (x, 1,
+					      sizeof (x), f) != sizeof (x),
+			    0))
+	goto lose;
+      c = getc_unlocked (f);
+      if (__glibc_unlikely ((unsigned int) c > 1u))
+	goto lose;
+      types[i].isdst = c;
+      c = getc_unlocked (f);
+      if (__glibc_unlikely ((size_t) c > chars))
+	/* Bogus index in data file.  */
+	goto lose;
+      types[i].idx = c;
+      types[i].offset = (long int) decode (x);
+    }
+
+  if (__glibc_unlikely (__fread_unlocked (zone_names, 1, chars, f) != chars))
+    goto lose;
+
+  for (i = 0; i < num_leaps; ++i)
+    {
+      unsigned char x[8];
+      if (__builtin_expect (__fread_unlocked (x, 1, trans_width, f)
+			    != trans_width, 0))
+	goto lose;
+      if (sizeof (time_t) == 4 || trans_width == 4)
+	leaps[i].transition = (time_t) decode (x);
+      else
+	leaps[i].transition = (time_t) decode64 (x);
+
+      if (__glibc_unlikely (__fread_unlocked (x, 1, 4, f) != 4))
+	goto lose;
+      leaps[i].change = (long int) decode (x);
+    }
+
+  for (i = 0; i < num_isstd; ++i)
+    {
+      int c = getc_unlocked (f);
+      if (__glibc_unlikely (c == EOF))
+	goto lose;
+      types[i].isstd = c != 0;
+    }
+  while (i < num_types)
+    types[i++].isstd = 0;
+
+  for (i = 0; i < num_isgmt; ++i)
+    {
+      int c = getc_unlocked (f);
+      if (__glibc_unlikely (c == EOF))
+	goto lose;
+      types[i].isgmt = c != 0;
+    }
+  while (i < num_types)
+    types[i++].isgmt = 0;
+
+  /* Read the POSIX TZ-style information if possible.  */
+  if (sizeof (time_t) == 8 && tzspec != NULL)
+    {
+      /* Skip over the newline first.  */
+      if (getc_unlocked (f) != '\n'
+	  || (__fread_unlocked (tzspec, 1, tzspec_len - 1, f)
+	      != tzspec_len - 1))
+	tzspec = NULL;
+      else
+	tzspec[tzspec_len - 1] = '\0';
+    }
+  else if (sizeof (time_t) == 4 && tzhead.tzh_version[0] != '\0')
+    {
+      /* Get the TZ string.  */
+      if (__builtin_expect (__fread_unlocked ((void *) &tzhead,
+					      sizeof (tzhead), 1, f) != 1, 0)
+	  || (memcmp (tzhead.tzh_magic, TZ_MAGIC, sizeof (tzhead.tzh_magic))
+	      != 0))
+	goto lose;
+
+      size_t num_transitions2 = (size_t) decode (tzhead.tzh_timecnt);
+      size_t num_types2 = (size_t) decode (tzhead.tzh_typecnt);
+      size_t chars2 = (size_t) decode (tzhead.tzh_charcnt);
+      size_t num_leaps2 = (size_t) decode (tzhead.tzh_leapcnt);
+      size_t num_isstd2 = (size_t) decode (tzhead.tzh_ttisstdcnt);
+      size_t num_isgmt2 = (size_t) decode (tzhead.tzh_ttisgmtcnt);
+
+      /* Position the stream before the second header.  */
+      size_t to_skip = (num_transitions2 * (8 + 1)
+			+ num_types2 * 6
+			+ chars2
+			+ num_leaps2 * 12
+			+ num_isstd2
+			+ num_isgmt2);
+      off_t off;
+      if (fseek (f, to_skip, SEEK_CUR) != 0
+	  || (off = __ftello (f)) < 0
+	  || st.st_size < off + 2)
+	goto lose;
+
+      tzspec_len = st.st_size - off - 1;
+      if (tzspec_len == 0)
+	goto lose;
+      char *tzstr = malloc (tzspec_len);
+      if (tzstr == NULL)
+	goto lose;
+      if (getc_unlocked (f) != '\n'
+	  || (__fread_unlocked (tzstr, 1, tzspec_len - 1, f)
+	      != tzspec_len - 1))
+	{
+	  free (tzstr);
+	  goto lose;
+	}
+      tzstr[tzspec_len - 1] = '\0';
+      tzspec = __tzstring (tzstr);
+      free (tzstr);
+    }
+
+  /* Don't use an empty TZ string.  */
+  if (tzspec != NULL && tzspec[0] == '\0')
+    tzspec = NULL;
+
+  fclose (f);
+
+  /* First "register" all timezone names.  */
+  for (i = 0; i < num_types; ++i)
+    (void) __tzstring (&zone_names[types[i].idx]);
+
+  /* Find the standard and daylight time offsets used by the rule file.
+     We choose the offsets in the types of each flavor that are
+     transitioned to earliest in time.  */
+  __tzname[0] = NULL;
+  __tzname[1] = NULL;
+  for (i = num_transitions; i > 0; )
+    {
+      int type = type_idxs[--i];
+      int dst = types[type].isdst;
+
+      if (__tzname[dst] == NULL)
+	{
+	  int idx = types[type].idx;
+
+	  __tzname[dst] = __tzstring (&zone_names[idx]);
+
+	  if (__tzname[1 - dst] != NULL)
+	    break;
+	}
+    }
+  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)
+    __tzname[1] = __tzname[0];
+
+  compute_tzname_max (chars);
+
+  if (num_transitions == 0)
+    /* Use the first rule (which should also be the only one).  */
+    rule_stdoff = rule_dstoff = types[0].offset;
+  else
+    {
+      int stdoff_set = 0, dstoff_set = 0;
+      rule_stdoff = rule_dstoff = 0;
+      i = num_transitions - 1;
+      do
+	{
+	  if (!stdoff_set && !types[type_idxs[i]].isdst)
+	    {
+	      stdoff_set = 1;
+	      rule_stdoff = types[type_idxs[i]].offset;
+	    }
+	  else if (!dstoff_set && types[type_idxs[i]].isdst)
+	    {
+	      dstoff_set = 1;
+	      rule_dstoff = types[type_idxs[i]].offset;
+	    }
+	  if (stdoff_set && dstoff_set)
+	    break;
+	}
+      while (i-- > 0);
+
+      if (!dstoff_set)
+	rule_dstoff = rule_stdoff;
+    }
+
+  __daylight = rule_stdoff != rule_dstoff;
+  __timezone = -rule_stdoff;
+
+ done:
+  __use_tzfile = 1;
+  free (new);
+  return;
+
+ lose:
+  fclose (f);
+ ret_free_transitions:
+  free (new);
+  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);
+
+  /* Invalidate the tzfile attribute cache to force rereading
+     TZDEFRULES the next time it is used.  */
+  tzfile_dev = 0;
+  tzfile_ino = 0;
+  tzfile_mtime = 0;
+}
+
+void
+__tzfile_compute (time_t timer, int use_localtime,
+		  long int *leap_correct, int *leap_hit,
+		  struct tm *tp)
+{
+  size_t i;
+
+  if (use_localtime)
+    {
+      __tzname[0] = NULL;
+      __tzname[1] = NULL;
+
+      if (__glibc_unlikely (num_transitions == 0 || timer < transitions[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 (__glibc_unlikely (timer >= transitions[num_transitions - 1]))
+	{
+	  if (__glibc_unlikely (tzspec == NULL))
+	    {
+	    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 (__glibc_unlikely (! __offtime (&timer, 0, tp)))
+	    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 (__glibc_unlikely (zone_names == (char *) &leaps[num_leaps]))
+	    {
+	      assert (num_types == 2);
+	      __tzname[0] = __tzstring (zone_names);
+	      __tzname[1] = __tzstring (&zone_names[strlen (zone_names) + 1]);
+	    }
+
+	  goto leap;
+	}
+      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 (__glibc_unlikely (__tzname[0] == NULL))
+	    __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:
+  *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]);
+}