Prepare for radical source tree reorganization. zack/build-layout-experiment

All top-level files and directories are moved into a temporary storage
directory, REORG.TODO, except for files that will certainly still
exist in their current form at top level when we're done (COPYING,
COPYING.LIB, LICENSES, NEWS, README), all old ChangeLog files (which
are moved to the new directory OldChangeLogs, instead), and the
generated file INSTALL (which is just deleted; in the new order, there
will be no generated files checked into version control).

1 files changed, 632 insertions, 0 deletions

diff --git a/REORG.TODO/time/tzset.c b/REORG.TODO/time/tzset.c
new file mode 100644
index 0000000000..8868e9aada
--- /dev/null
+++ b/REORG.TODO/time/tzset.c
@@ -0,0 +1,632 @@
+/* Copyright (C) 1991-2017 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 <ctype.h>
+#include <errno.h>
+#include <libc-lock.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+
+#include <timezone/tzfile.h>
+
+char *__tzname[2] = { (char *) "GMT", (char *) "GMT" };
+int __daylight = 0;
+long int __timezone = 0L;
+
+weak_alias (__tzname, tzname)
+weak_alias (__daylight, daylight)
+weak_alias (__timezone, timezone)
+
+/* This locks all the state variables in tzfile.c and this file.  */
+__libc_lock_define_initialized (static, tzset_lock)
+
+/* This structure contains all the information about a
+   timezone given in the POSIX standard TZ envariable.  */
+typedef struct
+  {
+    const char *name;
+
+    /* When to change.  */
+    enum { J0, J1, M } type;	/* Interpretation of:  */
+    unsigned short int m, n, d;	/* Month, week, day.  */
+    int secs;			/* Time of day.  */
+
+    long int offset;		/* Seconds east of GMT (west if < 0).  */
+
+    /* We cache the computed time of change for a
+       given year so we don't have to recompute it.  */
+    time_t change;	/* When to change to this zone.  */
+    int computed_for;	/* Year above is computed for.  */
+  } tz_rule;
+
+/* tz_rules[0] is standard, tz_rules[1] is daylight.  */
+static tz_rule tz_rules[2];
+
+
+static void compute_change (tz_rule *rule, int year) __THROW internal_function;
+static void tzset_internal (int always);
+
+/* List of buffers containing time zone strings. */
+struct tzstring_l
+{
+  struct tzstring_l *next;
+  size_t len;  /* strlen(data) - doesn't count terminating NUL! */
+  char data[0];
+};
+
+static struct tzstring_l *tzstring_list;
+
+/* Allocate a permanent home for the first LEN characters of S.  It
+   will never be moved or deallocated, but may share space with other
+   strings.  Don't modify the returned string. */
+static char *
+__tzstring_len (const char *s, size_t len)
+{
+  char *p;
+  struct tzstring_l *t, *u, *new;
+
+  /* Walk the list and look for a match.  If this string is the same
+     as the end of an already-allocated string, it can share space. */
+  for (u = t = tzstring_list; t; u = t, t = t->next)
+    if (len <= t->len)
+      {
+	p = &t->data[t->len - len];
+	if (memcmp (s, p, len) == 0)
+	  return p;
+      }
+
+  /* Not found; allocate a new buffer. */
+  new = malloc (sizeof (struct tzstring_l) + len + 1);
+  if (!new)
+    return NULL;
+
+  new->next = NULL;
+  new->len = len;
+  memcpy (new->data, s, len);
+  new->data[len] = '\0';
+
+  if (u)
+    u->next = new;
+  else
+    tzstring_list = new;
+
+  return new->data;
+}
+
+/* Allocate a permanent home for S.  It will never be moved or
+   deallocated, but may share space with other strings.  Don't modify
+   the returned string. */
+char *
+__tzstring (const char *s)
+{
+  return __tzstring_len (s, strlen (s));
+}
+
+static char *old_tz;
+
+static void
+internal_function
+update_vars (void)
+{
+  __daylight = tz_rules[0].offset != tz_rules[1].offset;
+  __timezone = -tz_rules[0].offset;
+  __tzname[0] = (char *) tz_rules[0].name;
+  __tzname[1] = (char *) tz_rules[1].name;
+}
+
+
+static unsigned int
+compute_offset (unsigned int ss, unsigned int mm, unsigned int hh)
+{
+  if (ss > 59)
+    ss = 59;
+  if (mm > 59)
+    mm = 59;
+  if (hh > 24)
+    hh = 24;
+  return ss + mm * 60 + hh * 60 * 60;
+}
+
+/* Parses the time zone name at *TZP, and writes a pointer to an
+   interned string to tz_rules[WHICHRULE].name.  On success, advances
+   *TZP, and returns true.  Returns false otherwise.  */
+static bool
+parse_tzname (const char **tzp, int whichrule)
+{
+  const char *start = *tzp;
+  const char *p = start;
+  while (('a' <= *p && *p <= 'z')
+	 || ('A' <= *p && *p <= 'Z'))
+      ++p;
+  size_t len = p - start;
+  if (len < 3)
+    {
+      p = *tzp;
+      if (__glibc_unlikely (*p++ != '<'))
+	return false;
+      start = p;
+      while (('a' <= *p && *p <= 'z')
+	     || ('A' <= *p && *p <= 'Z')
+	     || ('0' <= *p && *p <= '9')
+	     || *p == '+' || *p == '-')
+	++p;
+      len = p - start;
+      if (*p++ != '>' || len < 3)
+	return false;
+    }
+
+  const char *name = __tzstring_len (start, len);
+  if (name == NULL)
+    return false;
+  tz_rules[whichrule].name = name;
+
+  *tzp = p;
+  return true;
+}
+
+/* Parses the time zone offset at *TZP, and writes it to
+   tz_rules[WHICHRULE].offset.  Returns true if the parse was
+   successful.  */
+static bool
+parse_offset (const char **tzp, int whichrule)
+{
+  const char *tz = *tzp;
+  if (whichrule == 0
+      && (*tz == '\0' || (*tz != '+' && *tz != '-' && !isdigit (*tz))))
+    return false;
+
+  long sign;
+  if (*tz == '-' || *tz == '+')
+    sign = *tz++ == '-' ? 1L : -1L;
+  else
+    sign = -1L;
+  *tzp = tz;
+
+  unsigned short int hh;
+  unsigned short mm = 0;
+  unsigned short ss = 0;
+  int consumed = 0;
+  if (sscanf (tz, "%hu%n:%hu%n:%hu%n",
+	      &hh, &consumed, &mm, &consumed, &ss, &consumed) > 0)
+    tz_rules[whichrule].offset = sign * compute_offset (ss, mm, hh);
+  else
+    /* Nothing could be parsed. */
+    if (whichrule == 0)
+      {
+	/* Standard time defaults to offset zero.  */
+	tz_rules[0].offset = 0;
+	return false;
+      }
+      else
+	/* DST defaults to one hour later than standard time.  */
+	tz_rules[1].offset = tz_rules[0].offset + (60 * 60);
+  *tzp = tz + consumed;
+  return true;
+}
+
+/* Parses the standard <-> DST rules at *TZP.  Updates
+   tz_rule[WHICHRULE].  On success, advances *TZP and returns true.
+   Otherwise, returns false.  */
+static bool
+parse_rule (const char **tzp, int whichrule)
+{
+  const char *tz = *tzp;
+  tz_rule *tzr = &tz_rules[whichrule];
+
+  /* Ignore comma to support string following the incorrect
+     specification in early POSIX.1 printings.  */
+  tz += *tz == ',';
+
+  /* Get the date of the change.  */
+  if (*tz == 'J' || isdigit (*tz))
+    {
+      char *end;
+      tzr->type = *tz == 'J' ? J1 : J0;
+      if (tzr->type == J1 && !isdigit (*++tz))
+	return false;
+      unsigned long int d = strtoul (tz, &end, 10);
+      if (end == tz || d > 365)
+	return false;
+      if (tzr->type == J1 && d == 0)
+	return false;
+      tzr->d = d;
+      tz = end;
+    }
+  else if (*tz == 'M')
+    {
+      tzr->type = M;
+      int consumed;
+      if (sscanf (tz, "M%hu.%hu.%hu%n",
+		  &tzr->m, &tzr->n, &tzr->d, &consumed) != 3
+	  || tzr->m < 1 || tzr->m > 12
+	  || tzr->n < 1 || tzr->n > 5 || tzr->d > 6)
+	return false;
+      tz += consumed;
+    }
+  else if (*tz == '\0')
+    {
+      /* Daylight time rules in the U.S. are defined in the U.S. Code,
+	 Title 15, Chapter 6, Subchapter IX - Standard Time.  These
+	 dates were established by Congress in the Energy Policy Act
+	 of 2005 [Pub. L. no. 109-58, 119 Stat 594 (2005)].
+	 Below is the equivalent of "M3.2.0,M11.1.0" [/2 not needed
+	 since 2:00AM is the default].  */
+      tzr->type = M;
+      if (tzr == &tz_rules[0])
+	{
+	  tzr->m = 3;
+	  tzr->n = 2;
+	  tzr->d = 0;
+	}
+      else
+	{
+	  tzr->m = 11;
+	  tzr->n = 1;
+	  tzr->d = 0;
+	}
+    }
+  else
+    return false;
+
+  if (*tz != '\0' && *tz != '/' && *tz != ',')
+    return false;
+  else if (*tz == '/')
+    {
+      /* Get the time of day of the change.  */
+      int negative;
+      ++tz;
+      if (*tz == '\0')
+	return false;
+      negative = *tz == '-';
+      tz += negative;
+      /* Default to 2:00 AM.  */
+      unsigned short hh = 2;
+      unsigned short mm = 0;
+      unsigned short ss = 0;
+      int consumed = 0;
+      sscanf (tz, "%hu%n:%hu%n:%hu%n",
+	      &hh, &consumed, &mm, &consumed, &ss, &consumed);;
+      tz += consumed;
+      tzr->secs = (negative ? -1 : 1) * ((hh * 60 * 60) + (mm * 60) + ss);
+    }
+  else
+    /* Default to 2:00 AM.  */
+    tzr->secs = 2 * 60 * 60;
+
+  tzr->computed_for = -1;
+  *tzp = tz;
+  return true;
+}
+
+/* Parse the POSIX TZ-style string.  */
+void
+__tzset_parse_tz (const char *tz)
+{
+  /* Clear out old state and reset to unnamed UTC.  */
+  memset (tz_rules, '\0', sizeof tz_rules);
+  tz_rules[0].name = tz_rules[1].name = "";
+
+  /* Get the standard timezone name.  */
+  if (parse_tzname (&tz, 0) && parse_offset (&tz, 0))
+    {
+      /* Get the DST timezone name (if any).  */
+      if (*tz != '\0')
+	{
+	  if (parse_tzname (&tz, 1))
+	    {
+	      parse_offset (&tz, 1);
+	      if (*tz == '\0' || (tz[0] == ',' && tz[1] == '\0'))
+		{
+		  /* There is no rule.  See if there is a default rule
+		     file.  */
+		  __tzfile_default (tz_rules[0].name, tz_rules[1].name,
+				    tz_rules[0].offset, tz_rules[1].offset);
+		  if (__use_tzfile)
+		    {
+		      free (old_tz);
+		      old_tz = NULL;
+		      return;
+		    }
+		}
+	    }
+	  /* Figure out the standard <-> DST rules.  */
+	  if (parse_rule (&tz, 0))
+	    parse_rule (&tz, 1);
+	}
+      else
+	{
+	  /* There is no DST.  */
+	  tz_rules[1].name = tz_rules[0].name;
+	  tz_rules[1].offset = tz_rules[0].offset;
+	}
+    }
+
+  update_vars ();
+}
+
+/* Interpret the TZ envariable.  */
+static void
+tzset_internal (int always)
+{
+  static int is_initialized;
+  const char *tz;
+
+  if (is_initialized && !always)
+    return;
+  is_initialized = 1;
+
+  /* Examine the TZ environment variable.  */
+  tz = getenv ("TZ");
+  if (tz && *tz == '\0')
+    /* User specified the empty string; use UTC explicitly.  */
+    tz = "Universal";
+
+  /* A leading colon means "implementation defined syntax".
+     We ignore the colon and always use the same algorithm:
+     try a data file, and if none exists parse the 1003.1 syntax.  */
+  if (tz && *tz == ':')
+    ++tz;
+
+  /* Check whether the value changed since the last run.  */
+  if (old_tz != NULL && tz != NULL && strcmp (tz, old_tz) == 0)
+    /* No change, simply return.  */
+    return;
+
+  if (tz == NULL)
+    /* No user specification; use the site-wide default.  */
+    tz = TZDEFAULT;
+
+  tz_rules[0].name = NULL;
+  tz_rules[1].name = NULL;
+
+  /* Save the value of `tz'.  */
+  free (old_tz);
+  old_tz = tz ? __strdup (tz) : NULL;
+
+  /* Try to read a data file.  */
+  __tzfile_read (tz, 0, NULL);
+  if (__use_tzfile)
+    return;
+
+  /* No data file found.  Default to UTC if nothing specified.  */
+
+  if (tz == NULL || *tz == '\0'
+      || (TZDEFAULT != NULL && strcmp (tz, TZDEFAULT) == 0))
+    {
+      memset (tz_rules, '\0', sizeof tz_rules);
+      tz_rules[0].name = tz_rules[1].name = "UTC";
+      if (J0 != 0)
+	tz_rules[0].type = tz_rules[1].type = J0;
+      tz_rules[0].change = tz_rules[1].change = (time_t) -1;
+      update_vars ();
+      return;
+    }
+
+  __tzset_parse_tz (tz);
+}
+
+/* Figure out the exact time (as a time_t) in YEAR
+   when the change described by RULE will occur and
+   put it in RULE->change, saving YEAR in RULE->computed_for.  */
+static void
+internal_function
+compute_change (tz_rule *rule, int year)
+{
+  time_t t;
+
+  if (year != -1 && rule->computed_for == year)
+    /* Operations on times in 2 BC will be slower.  Oh well.  */
+    return;
+
+  /* First set T to January 1st, 0:00:00 GMT in YEAR.  */
+  if (year > 1970)
+    t = ((year - 1970) * 365
+	 + /* Compute the number of leapdays between 1970 and YEAR
+	      (exclusive).  There is a leapday every 4th year ...  */
+	 + ((year - 1) / 4 - 1970 / 4)
+	 /* ... except every 100th year ... */
+	 - ((year - 1) / 100 - 1970 / 100)
+	 /* ... but still every 400th year.  */
+	 + ((year - 1) / 400 - 1970 / 400)) * SECSPERDAY;
+  else
+    t = 0;
+
+  switch (rule->type)
+    {
+    case J1:
+      /* Jn - Julian day, 1 == January 1, 60 == March 1 even in leap years.
+	 In non-leap years, or if the day number is 59 or less, just
+	 add SECSPERDAY times the day number-1 to the time of
+	 January 1, midnight, to get the day.  */
+      t += (rule->d - 1) * SECSPERDAY;
+      if (rule->d >= 60 && __isleap (year))
+	t += SECSPERDAY;
+      break;
+
+    case J0:
+      /* n - Day of year.
+	 Just add SECSPERDAY times the day number to the time of Jan 1st.  */
+      t += rule->d * SECSPERDAY;
+      break;
+
+    case M:
+      /* Mm.n.d - Nth "Dth day" of month M.  */
+      {
+	unsigned int i;
+	int d, m1, yy0, yy1, yy2, dow;
+	const unsigned short int *myday =
+	  &__mon_yday[__isleap (year)][rule->m];
+
+	/* First add SECSPERDAY for each day in months before M.  */
+	t += myday[-1] * SECSPERDAY;
+
+	/* Use Zeller's Congruence to get day-of-week of first day of month. */
+	m1 = (rule->m + 9) % 12 + 1;
+	yy0 = (rule->m <= 2) ? (year - 1) : year;
+	yy1 = yy0 / 100;
+	yy2 = yy0 % 100;
+	dow = ((26 * m1 - 2) / 10 + 1 + yy2 + yy2 / 4 + yy1 / 4 - 2 * yy1) % 7;
+	if (dow < 0)
+	  dow += 7;
+
+	/* DOW is the day-of-week of the first day of the month.  Get the
+	   day-of-month (zero-origin) of the first DOW day of the month.  */
+	d = rule->d - dow;
+	if (d < 0)
+	  d += 7;
+	for (i = 1; i < rule->n; ++i)
+	  {
+	    if (d + 7 >= (int) myday[0] - myday[-1])
+	      break;
+	    d += 7;
+	  }
+
+	/* D is the day-of-month (zero-origin) of the day we want.  */
+	t += d * SECSPERDAY;
+      }
+      break;
+    }
+
+  /* T is now the Epoch-relative time of 0:00:00 GMT on the day we want.
+     Just add the time of day and local offset from GMT, and we're done.  */
+
+  rule->change = t - rule->offset + rule->secs;
+  rule->computed_for = year;
+}
+
+
+/* Figure out the correct timezone for TM and set `__tzname',
+   `__timezone', and `__daylight' accordingly.  */
+void
+internal_function
+__tz_compute (time_t timer, struct tm *tm, int use_localtime)
+{
+  compute_change (&tz_rules[0], 1900 + tm->tm_year);
+  compute_change (&tz_rules[1], 1900 + tm->tm_year);
+
+  if (use_localtime)
+    {
+      int isdst;
+
+      /* We have to distinguish between northern and southern
+	 hemisphere.  For the latter the daylight saving time
+	 ends in the next year.  */
+      if (__builtin_expect (tz_rules[0].change
+			    > tz_rules[1].change, 0))
+	isdst = (timer < tz_rules[1].change
+		 || timer >= tz_rules[0].change);
+      else
+	isdst = (timer >= tz_rules[0].change
+		 && timer < tz_rules[1].change);
+      tm->tm_isdst = isdst;
+      tm->tm_zone = __tzname[isdst];
+      tm->tm_gmtoff = tz_rules[isdst].offset;
+    }
+}
+
+/* Reinterpret the TZ environment variable and set `tzname'.  */
+#undef tzset
+
+void
+__tzset (void)
+{
+  __libc_lock_lock (tzset_lock);
+
+  tzset_internal (1);
+
+  if (!__use_tzfile)
+    {
+      /* Set `tzname'.  */
+      __tzname[0] = (char *) tz_rules[0].name;
+      __tzname[1] = (char *) tz_rules[1].name;
+    }
+
+  __libc_lock_unlock (tzset_lock);
+}
+weak_alias (__tzset, tzset)
+
+/* Return the `struct tm' representation of *TIMER in the local timezone.
+   Use local time if USE_LOCALTIME is nonzero, UTC otherwise.  */
+struct tm *
+__tz_convert (const time_t *timer, int use_localtime, struct tm *tp)
+{
+  long int leap_correction;
+  int leap_extra_secs;
+
+  if (timer == NULL)
+    {
+      __set_errno (EINVAL);
+      return NULL;
+    }
+
+  __libc_lock_lock (tzset_lock);
+
+  /* Update internal database according to current TZ setting.
+     POSIX.1 8.3.7.2 says that localtime_r is not required to set tzname.
+     This is a good idea since this allows at least a bit more parallelism.  */
+  tzset_internal (tp == &_tmbuf && use_localtime);
+
+  if (__use_tzfile)
+    __tzfile_compute (*timer, use_localtime, &leap_correction,
+		      &leap_extra_secs, tp);
+  else
+    {
+      if (! __offtime (timer, 0, tp))
+	tp = NULL;
+      else
+	__tz_compute (*timer, tp, use_localtime);
+      leap_correction = 0L;
+      leap_extra_secs = 0;
+    }
+
+  __libc_lock_unlock (tzset_lock);
+
+  if (tp)
+    {
+      if (! use_localtime)
+	{
+	  tp->tm_isdst = 0;
+	  tp->tm_zone = "GMT";
+	  tp->tm_gmtoff = 0L;
+	}
+
+      if (__offtime (timer, tp->tm_gmtoff - leap_correction, tp))
+        tp->tm_sec += leap_extra_secs;
+      else
+	tp = NULL;
+    }
+
+  return tp;
+}
+
+
+libc_freeres_fn (free_mem)
+{
+  while (tzstring_list != NULL)
+    {
+      struct tzstring_l *old = tzstring_list;
+
+      tzstring_list = tzstring_list->next;
+      free (old);
+    }
+  free (old_tz);
+  old_tz = NULL;
+}