initial import

1 files changed, 332 insertions, 0 deletions

diff --git a/time/tzfile.c b/time/tzfile.c
new file mode 100644
index 0000000..841f598
--- /dev/null
+++ b/time/tzfile.c
@@ -0,0 +1,332 @@
+/* Copyright (C) 1991, 1992, 1993 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 Library General Public License as
+published by the Free Software Foundation; either version 2 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
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#include <ansidecl.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <time.h>
+#include <string.h>
+#include <limits.h>
+
+#define	NOID
+#include <tzfile.h>
+
+#ifndef	HAVE_GNU_LD
+#define	__tzname	tzname
+#define	__daylight	daylight
+#define	__timezone	timezone
+#endif
+
+int __use_tzfile = 0;
+
+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 standard time.  */
+  };
+
+struct leap
+  {
+    time_t transition;		/* Time the transition takes effect.  */
+    long int change;		/* Seconds of correction to apply.  */
+  };
+
+static void compute_tzname_max __P ((size_t));
+
+static size_t num_transitions;
+static time_t *transitions = NULL;
+static unsigned char *type_idxs = NULL;
+static size_t num_types;
+static struct ttinfo *types = NULL;
+static char *zone_names = NULL;
+static size_t num_leaps;
+static struct leap *leaps = NULL;
+
+#define	uc2ul(x)	_uc2ul((unsigned char *) (x))
+#define	_uc2ul(x)							      \
+  ((x)[3] + ((x)[2] << CHAR_BIT) + ((x)[1] << (2 * CHAR_BIT)) +		      \
+   ((x)[0] << (3 * CHAR_BIT)))
+
+void
+DEFUN(__tzfile_read, (file), CONST char *file)
+{
+  size_t num_isstd;
+  register FILE *f;
+  struct tzhead tzhead;
+  size_t chars;
+  register size_t i;
+
+  __use_tzfile = 0;
+
+  if (transitions != NULL)
+    free((PTR) transitions);
+  transitions = NULL;
+  if (type_idxs != NULL)
+    free((PTR) type_idxs);
+  type_idxs = NULL;
+  if (types != NULL)
+    free((PTR) types);
+  types = NULL;
+  if (zone_names != NULL)
+    free((PTR) zone_names);
+  zone_names = NULL;
+  if (leaps != NULL)
+    free((PTR) leaps);
+  leaps = NULL;
+
+  if (file == NULL || *file == '\0')
+    file = TZDEFAULT;
+
+  if (*file != '/')
+    {
+      static CONST char tzdir[] = TZDIR;
+      register CONST unsigned int len = strlen(file) + 1;
+      char *new = (char *) __alloca(sizeof(tzdir) + len);
+      memcpy(new, tzdir, sizeof(tzdir) - 1);
+      new[sizeof(tzdir) - 1] = '/';
+      memcpy(&new[sizeof(tzdir)], file, len);
+      file = new;
+    }
+
+  f = fopen(file, "r");
+  if (f == NULL)
+    return;
+
+  if (fread((PTR) &tzhead, sizeof(tzhead), 1, f) != 1)
+    goto lose;
+
+  num_transitions = (size_t) uc2ul(tzhead.tzh_timecnt);
+  num_types = (size_t) uc2ul(tzhead.tzh_typecnt);
+  chars = (size_t) uc2ul(tzhead.tzh_charcnt);
+  num_leaps = (size_t) uc2ul(tzhead.tzh_leapcnt);
+  num_isstd = (size_t) uc2ul(tzhead.tzh_ttisstdcnt);
+
+  if (num_transitions > 0)
+    {
+      transitions = (time_t *) malloc (num_transitions * sizeof(time_t));
+      if (transitions == NULL)
+	goto lose;
+      type_idxs = (unsigned char *) malloc (num_transitions);
+      if (type_idxs == NULL)
+	goto lose;
+    }
+  if (num_types > 0)
+    {
+      types = (struct ttinfo *) malloc (num_types * sizeof (struct ttinfo));
+      if (types == NULL)
+	goto lose;
+    }
+  if (chars > 0)
+    {
+      zone_names = (char *) malloc (chars);
+      if (zone_names == NULL)
+	goto lose;
+    }
+  if (num_leaps > 0)
+    {
+      leaps = (struct leap *) malloc (num_leaps * sizeof (struct leap));
+      if (leaps == NULL)
+	goto lose;
+    }
+
+  if (fread((PTR) transitions, sizeof(time_t),
+	    num_transitions, f) != num_transitions ||
+      fread((PTR) type_idxs, 1, num_transitions, f) != num_transitions)
+    goto lose;
+
+  for (i = 0; i < num_transitions; ++i)
+    transitions[i] = uc2ul (&transitions[i]);
+
+  for (i = 0; i < num_types; ++i)
+    {
+      unsigned char x[4];
+      if (fread((PTR) x, 1, 4, f) != 4 ||
+	  fread((PTR) &types[i].isdst, 1, 1, f) != 1 ||
+	  fread((PTR) &types[i].idx, 1, 1, f) != 1)
+	goto lose;
+      types[i].offset = (long int) uc2ul(x);
+    }
+
+  if (fread((PTR) zone_names, 1, chars, f) != chars)
+    goto lose;
+
+  for (i = 0; i < num_leaps; ++i)
+    {
+      unsigned char x[4];
+      if (fread((PTR) x, 1, sizeof(x), f) != sizeof(x))
+	goto lose;
+      leaps[i].transition = (time_t) uc2ul(x);
+      if (fread((PTR) x, 1, sizeof(x), f) != sizeof(x))
+	goto lose;
+      leaps[i].change = (long int) uc2ul(x);
+    }
+
+  for (i = 0; i < num_isstd; ++i)
+    {
+      char c = getc(f);
+      if (c == EOF)
+	goto lose;
+      types[i].isstd = c != 0;
+    }
+  while (i < num_types)
+    types[i++].isstd = 0;
+
+  (void) fclose(f);
+
+  compute_tzname_max (chars);
+  
+  __use_tzfile = 1;
+  return;
+
+ lose:;
+  (void) fclose(f);
+}
+
+void
+DEFUN(__tzfile_default, (std, dst, stdoff, dstoff),
+      char *std AND char *dst AND
+      long int stdoff AND long int dstoff)
+{
+  size_t stdlen, dstlen, i;
+
+  __tzfile_read (TZDEFRULES);
+  if (!__use_tzfile)
+    return;
+
+  if (num_types < 2)
+    {
+      __use_tzfile = 0;
+      return;
+    }
+
+  free (zone_names);
+
+  stdlen = strlen (std) + 1;
+  dstlen = strlen (dst) + 1;
+  zone_names = malloc (stdlen + dstlen);
+  if (zone_names == NULL)
+    {
+      __use_tzfile = 0;
+      return;
+    }
+  memcpy (zone_names, std, stdlen);
+  memcpy (&zone_names[stdlen], dst, dstlen);
+
+  for (i = 0; i < num_types; ++i)
+    if (types[i].isdst)
+      {
+	types[i].idx = stdlen;
+	if (dst[0] != '\0')
+	  types[i].offset = dstoff;
+      }
+    else
+      {
+	types[i].idx = 0;
+	if (dst[0] != '\0')
+	  types[i].offset = stdoff;
+      }
+
+  compute_tzname_max (stdlen + dstlen);
+}
+
+int
+DEFUN(__tzfile_compute, (timer, leap_correct, leap_hit),
+      time_t timer AND long int *leap_correct AND int *leap_hit)
+{
+  struct ttinfo *info;
+  register size_t i;
+
+  if (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)
+	++i;
+      if (i == num_types)
+	i = 0;
+    }
+  else
+    {
+      /* Find the first transition after TIMER, and
+	 then pick the type of the transition before it.  */
+      for (i = 1; i < num_transitions; ++i)
+	if (timer < transitions[i])
+	  break;
+      i = type_idxs[i - 1];
+    }
+
+  info = &types[i];
+  __daylight = info->isdst;
+  __timezone = info->offset;
+  for (i = 0; i < num_types && i < sizeof (__tzname) / sizeof (__tzname[0]);
+       ++i)
+    __tzname[types[i].isdst] = &zone_names[types[i].idx];
+  if (info->isdst < sizeof (__tzname) / sizeof (__tzname[0]))
+    __tzname[info->isdst] = &zone_names[info->idx];
+
+  *leap_correct = 0L;
+  *leap_hit = 0;
+
+  /* Find the last leap second correction transition time before TIMER.  */
+  i = num_leaps;
+  do
+    if (i-- == 0)
+      return 1;
+  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;
+	}
+    }
+
+  return 1;
+}
+
+void
+DEFUN(compute_tzname_max, (chars), size_t chars)
+{
+  extern long int __tzname_cur_max; /* Defined in __tzset.c. */
+
+  const char *p;
+
+  p = zone_names;
+  do
+    {
+      const char *start = p;
+      while (*p != '\0')
+	++p;
+      if (p - start > __tzname_cur_max)
+	__tzname_cur_max = p - start;
+    } while (++p < &zone_names[chars]);
+}