Guard local time posix functions from NaN value of invalid dates.

Review URL: http://codereview.chromium.org/160451

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2601 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/date-delay.js

@@ -156,6 +156,8 @@ var DST_offset_cache = {
 
 // NOTE: The implementation relies on the fact that no time zones have
 // more than one daylight savings offset change per month.
+// This function must never be called with the argument NaN.
+// All uses of it are guarded so this does not happen.
 function DaylightSavingsOffset(t) {
   // Load the cache object from the builtins object.
   var cache = DST_offset_cache;
@@ -219,6 +221,7 @@ var timezone_cache_time = $NaN;
 var timezone_cache_timezone;
 
 function LocalTimezone(t) {
+  if (NUMBER_IS_NAN(t)) return "";
   if (t == timezone_cache_time) {
     return timezone_cache_timezone;
   }
@@ -464,9 +467,11 @@ var Date_cache = {
         value = cache.time;
       } else {
         value = DateParse(year);
-        cache.time = value;
-        cache.year = YearFromTime(LocalTimeNoCheck(value));
-        cache.string = year;
+        if (!NUMBER_IS_NAN(value)) {
+          cache.time = value;
+          cache.year = YearFromTime(LocalTimeNoCheck(value));
+          cache.string = year;
+        }
       }
 
     } else {
@@ -647,6 +652,7 @@ function TimeString(time) {
 
 
 function LocalTimezoneString(time) {
+  // time is not NaN because of checks in calling functions.
   var timezoneOffset = (local_time_offset + DaylightSavingsOffset(time)) / msPerMinute;
   var sign = (timezoneOffset >= 0) ? 1 : -1;
   var hours = FLOOR((sign * timezoneOffset)/60);

src/platform-nullos.cc

@@ -80,7 +80,7 @@ int64_t OS::Ticks() {
 
 // Returns a string identifying the current timezone taking into
 // account daylight saving.
-char* OS::LocalTimezone(double time) {
+const char* OS::LocalTimezone(double time) {
   UNIMPLEMENTED();
   return "<none>";
 }

src/platform-posix.cc

@@ -86,16 +86,20 @@ int64_t OS::Ticks() {
 }
 
 
-char* OS::LocalTimezone(double time) {
+const char* OS::LocalTimezone(double time) {
+  ASSERT(!isnan(time));
   time_t tv = static_cast<time_t>(floor(time/msPerSecond));
   struct tm* t = localtime(&tv);
-  return const_cast<char*>(t->tm_zone);
+  if (NULL == t) return "";
+  return t->tm_zone;
 }
 
 
 double OS::DaylightSavingsOffset(double time) {
+  ASSERT(!isnan(time));
   time_t tv = static_cast<time_t>(floor(time/msPerSecond));
   struct tm* t = localtime(&tv);
+  if (NULL == t) return nan_value();
   return t->tm_isdst > 0 ? 3600 * msPerSecond : 0;
 }
 

src/platform-win32.cc

@@ -603,7 +603,7 @@ int64_t OS::Ticks() {
 
 // Returns a string identifying the current timezone taking into
 // account daylight saving.
-char* OS::LocalTimezone(double time) {
+const char* OS::LocalTimezone(double time) {
   return Time(time).LocalTimezone();
 }
 

src/platform.h

@@ -143,7 +143,7 @@ class OS {
 
   // Returns a string identifying the current time zone. The
   // timestamp is used for determining if DST is in effect.
-  static char* LocalTimezone(double time);
+  static const char* LocalTimezone(double time);
 
   // Returns the local time offset in milliseconds east of UTC without
   // taking daylight savings time into account.

test/mjsunit/mjsunit.status

@@ -101,6 +101,5 @@ fuzz-natives: PASS || TIMEOUT
 debug-handle: CRASH || FAIL
 debug-clearbreakpointgroup: CRASH || FAIL
 regress/regress-269: CRASH || FAIL
-regress/regress-1200351: CRASH || FAIL
 regress/regress-998565: CRASH || FAIL
 tools/tickprocessor: PASS || CRASH || FAIL