Fix localtime() and gmtime() with 64bit time_t (#17471)

See: #17393
emscripten-core · Jul 19, 2022 · 104a967 · 104a967
1 parent 73c1d12
commit 104a967
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Showing 3 changed files with 46 additions and 2 deletions.
diff --git a/src/library.js b/src/library.js
@@ -510,9 +510,10 @@ mergeInto(LibraryManager.library, {
     return (date.getTime() / 1000)|0;
   },
 
+  _gmtime_js__deps: ['$readI53FromI64'],
   _gmtime_js__sig: 'ipp',
   _gmtime_js: function(time, tmPtr) {
-    var date = new Date({{{ makeGetValue('time', 0, 'i32') }}}*1000);
+    var date = new Date({{{ makeGetValue('time', 0, 'i53') }}}*1000);
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_sec, 'date.getUTCSeconds()', 'i32') }}};
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_min, 'date.getUTCMinutes()', 'i32') }}};
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_hour, 'date.getUTCHours()', 'i32') }}};
@@ -544,9 +545,10 @@ mergeInto(LibraryManager.library, {
     return (date.getTime() / 1000)|0;
   },
 
+  _localtime_js__deps: ['$readI53FromI64'],
   _localtime_js__sig: 'ipp',
   _localtime_js: function(time, tmPtr) {
-    var date = new Date({{{ makeGetValue('time', 0, 'i32') }}}*1000);
+    var date = new Date({{{ makeGetValue('time', 0, 'i53') }}}*1000);
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_sec, 'date.getSeconds()', 'i32') }}};
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_min, 'date.getMinutes()', 'i32') }}};
     {{{ makeSetValue('tmPtr', C_STRUCTS.tm.tm_hour, 'date.getHours()', 'i32') }}};

diff --git a/tests/core/test_time.cpp b/tests/core/test_time.cpp
@@ -10,6 +10,30 @@
 #include <assert.h>
 #include <math.h>
 
+void
+check_gmtime_localtime(time_t time)
+{
+  char gmbuf[32], locbuf[32];
+  const char fmt[] = "%Y-%m-%d %H:%M:%S";
+  struct tm *gm;
+  struct tm *loc;
+
+  gm = gmtime(&time);
+  assert(gm);
+  assert(strftime(gmbuf, sizeof(gmbuf) - 1, fmt, gm) > 0);
+  loc = localtime(&time);
+  assert(loc);
+  assert(strftime(locbuf, sizeof(locbuf) - 1, fmt, loc) > 0);
+
+  // gmtime and localtime are only equal when timezone is UTC
+  if ((timezone == 0) && (strcmp(gmbuf, locbuf) != 0)) {
+    printf("time: %lld, gmtime: %s != localtime: %s\n", time, gmbuf, locbuf);
+    puts("failed");
+  } else {
+    printf("time: %lld, gmtime: %s\n", time, gmbuf);
+  }
+}
+
 int main() {
   time_t xmas2002 = 1040786563ll;
   time_t summer2002 = 1025528525ll;
@@ -216,5 +240,15 @@ int main() {
   clock_gettime(CLOCK_REALTIME, &ts_clock_gettime);
   printf("timespec_get test 6: %d\n", abs(ts_timespec_get.tv_sec - ts_clock_gettime.tv_sec) <= 2);
 
+  // verify gmtime() and localtime()
+  check_gmtime_localtime(0);
+  check_gmtime_localtime(2147483647); // int8_t max, Y2K38
+  check_gmtime_localtime(2147483648);
+  check_gmtime_localtime(-2147483648); // int8_t min
+  check_gmtime_localtime(-2147483649);
+  check_gmtime_localtime(253402300799); // end of year 9999
+  check_gmtime_localtime(-62135596800); // beginning of year 1
+
+  puts("success");
   return 0;
 }
diff --git a/tests/core/test_time.out b/tests/core/test_time.out
@@ -51,3 +51,11 @@ timespec_get test 3: 1
 timespec_get test 4: 1
 timespec_get test 5: 1
 timespec_get test 6: 1
+time: 0, gmtime: 1970-01-01 00:00:00
+time: 2147483647, gmtime: 2038-01-19 03:14:07
+time: 2147483648, gmtime: 2038-01-19 03:14:08
+time: -2147483648, gmtime: 1901-12-13 20:45:52
+time: -2147483649, gmtime: 1901-12-13 20:45:51
+time: 253402300799, gmtime: 9999-12-31 23:59:59
+time: -62135596800, gmtime: 1-01-01 00:00:00
+success