Merge from emacs--devo--0

[bpt/emacs.git] / src / editfns.c

diff --git a/src/editfns.c b/src/editfns.c
index 7c2c2a8..4578af6 100644 (file)
--- a/src/editfns.c
+++ b/src/editfns.c
@@ -72,6 +72,15 @@ Boston, MA 02110-1301, USA.  */
 extern char **environ;
 #endif
 
+#define TM_YEAR_BASE 1900
+
+/* Nonzero if TM_YEAR is a struct tm's tm_year value that causes
+   asctime to have well-defined behavior.  */
+#ifndef TM_YEAR_IN_ASCTIME_RANGE
+# define TM_YEAR_IN_ASCTIME_RANGE(tm_year) \
+    (1000 - TM_YEAR_BASE <= (tm_year) && (tm_year) <= 9999 - TM_YEAR_BASE)
+#endif
+
 extern size_t emacs_strftimeu P_ ((char *, size_t, const char *,
                                   const struct tm *, int));
 static int tm_diff P_ ((struct tm *, struct tm *));
@@ -480,7 +489,7 @@ get_pos_property (position, prop, object)
 }
 
 /* Find the field surrounding POS in *BEG and *END.  If POS is nil,
-   the value of point is used instead.  If BEG or END null,
+   the value of point is used instead.  If BEG or END is null,
    means don't store the beginning or end of the field.
 
    BEG_LIMIT and END_LIMIT serve to limit the ranged of the returned
@@ -719,7 +728,7 @@ Field boundaries are not noticed if `inhibit-field-text-motion' is non-nil.  */)
   int orig_point = 0;
   int fwd;
   Lisp_Object prev_old, prev_new;
-  
+
   if (NILP (new_pos))
     /* Use the current point, and afterwards, set it.  */
     {
@@ -734,7 +743,7 @@ Field boundaries are not noticed if `inhibit-field-text-motion' is non-nil.  */)
 
   prev_old = make_number (XFASTINT (old_pos) - 1);
   prev_new = make_number (XFASTINT (new_pos) - 1);
-  
+
   if (NILP (Vinhibit_field_text_motion)
       && !EQ (new_pos, old_pos)
       && (!NILP (Fget_char_property (new_pos, Qfield, Qnil))
@@ -812,6 +821,8 @@ This function does not move point.  */)
      Lisp_Object n;
 {
   int orig, orig_byte, end;
+  int count = SPECPDL_INDEX ();
+  specbind (Qinhibit_point_motion_hooks, Qt);
 
   if (NILP (n))
     XSETFASTINT (n, 1);
@@ -825,6 +836,8 @@ This function does not move point.  */)
 
   SET_PT_BOTH (orig, orig_byte);
 
+  unbind_to (count, Qnil);
+
   /* Return END constrained to the current input field.  */
   return Fconstrain_to_field (make_number (end), make_number (orig),
                              XINT (n) != 1 ? Qt : Qnil,
@@ -1720,7 +1733,9 @@ DOW and ZONE.)  */)
   XSETFASTINT (list_args[2], decoded_time->tm_hour);
   XSETFASTINT (list_args[3], decoded_time->tm_mday);
   XSETFASTINT (list_args[4], decoded_time->tm_mon + 1);
-  XSETINT (list_args[5], decoded_time->tm_year + 1900);
+  /* On 64-bit machines an int is narrower than EMACS_INT, thus the
+     cast below avoids overflow in int arithmetics.  */
+  XSETINT (list_args[5], TM_YEAR_BASE + (EMACS_INT) decoded_time->tm_year);
   XSETFASTINT (list_args[6], decoded_time->tm_wday);
   list_args[7] = (decoded_time->tm_isdst)? Qt : Qnil;
 
@@ -1776,7 +1791,7 @@ usage: (encode-time SECOND MINUTE HOUR DAY MONTH YEAR &optional ZONE)  */)
   tm.tm_hour = XINT (args[2]);
   tm.tm_mday = XINT (args[3]);
   tm.tm_mon = XINT (args[4]) - 1;
-  tm.tm_year = XINT (args[5]) - 1900;
+  tm.tm_year = XINT (args[5]) - TM_YEAR_BASE;
   tm.tm_isdst = -1;
 
   if (CONSP (zone))
@@ -1827,7 +1842,8 @@ usage: (encode-time SECOND MINUTE HOUR DAY MONTH YEAR &optional ZONE)  */)
 DEFUN ("current-time-string", Fcurrent_time_string, Scurrent_time_string, 0, 1, 0,
        doc: /* Return the current time, as a human-readable string.
 Programs can use this function to decode a time,
-since the number of columns in each field is fixed.
+since the number of columns in each field is fixed
+if the year is in the range 1000-9999.
 The format is `Sun Sep 16 01:03:52 1973'.
 However, see also the functions `decode-time' and `format-time-string'
 which provide a much more powerful and general facility.
@@ -1841,20 +1857,24 @@ but this is considered obsolete.  */)
      Lisp_Object specified_time;
 {
   time_t value;
-  char buf[30];
+  struct tm *tm;
   register char *tem;
 
   if (! lisp_time_argument (specified_time, &value, NULL))
-    value = -1;
-  tem = (char *) ctime (&value);
+    error ("Invalid time specification");
 
-  strncpy (buf, tem, 24);
-  buf[24] = 0;
+  /* Convert to a string, checking for out-of-range time stamps.
+     Don't use 'ctime', as that might dump core if VALUE is out of
+     range.  */
+  tm = localtime (&value);
+  if (! (tm && TM_YEAR_IN_ASCTIME_RANGE (tm->tm_year) && (tem = asctime (tm))))
+    error ("Specified time is not representable");
 
-  return build_string (buf);
-}
+  /* Remove the trailing newline.  */
+  tem[strlen (tem) - 1] = '\0';
 
-#define TM_YEAR_BASE 1900
+  return build_string (tem);
+}
 
 /* Yield A - B, measured in seconds.
    This function is copied from the GNU C Library.  */