Rewrite format_common_log

src/util.cc

@@ -239,53 +239,6 @@ char *http_date(char *res, time_t t) {
   return p;
 }
 
-std::string common_log_date(time_t t) {
-  // 03/Jul/2014:00:19:38 +0900
-  std::string res(26, 0);
-  common_log_date(&res[0], t);
-  return res;
-}
-
-char *common_log_date(char *res, time_t t) {
-  struct tm tms;
-
-  if (localtime_r(&t, &tms) == nullptr) {
-    return res;
-  }
-
-  auto p = res;
-
-  p = cpydig2(tms.tm_mday, p);
-  *p++ = '/';
-  p = std::ranges::copy(MONTH[tms.tm_mon], p).out;
-  *p++ = '/';
-  p = cpydig4(tms.tm_year + 1900, p);
-  *p++ = ':';
-  p = cpydig2(tms.tm_hour, p);
-  *p++ = ':';
-  p = cpydig2(tms.tm_min, p);
-  *p++ = ':';
-  p = cpydig2(tms.tm_sec, p);
-  *p++ = ' ';
-
-#ifdef HAVE_STRUCT_TM_TM_GMTOFF
-  auto gmtoff = tms.tm_gmtoff;
-#else  // !HAVE_STRUCT_TM_TM_GMTOFF
-  auto gmtoff = nghttp2_timegm(&tms) - t;
-#endif // !HAVE_STRUCT_TM_TM_GMTOFF
-  if (gmtoff >= 0) {
-    *p++ = '+';
-  } else {
-    *p++ = '-';
-    gmtoff = -gmtoff;
-  }
-
-  p = cpydig2(gmtoff / 3600, p);
-  p = cpydig2((gmtoff % 3600) / 60, p);
-
-  return p;
-}
-
 std::string format_iso8601(const std::chrono::system_clock::time_point &tp) {
   // 2014-11-15T12:58:24.741Z
   // 2014-11-15T12:58:24.741+09:00
@@ -411,6 +364,56 @@ StringRef format_iso8601_basic(char *out,
 
   return {out, p};
 }
+
+StringRef format_common_log(char *out,
+                            const std::chrono::system_clock::time_point &tp) {
+  return format_common_log(out, tp, get_current_time_zone());
+}
+
+StringRef format_common_log(char *out,
+                            const std::chrono::system_clock::time_point &tp,
+                            const std::chrono::time_zone *tz) {
+  auto t = std::chrono::floor<std::chrono::milliseconds>(tp);
+  auto zt = std::chrono::zoned_time{tz, t};
+  auto lt = zt.get_local_time();
+  auto days = std::chrono::floor<std::chrono::days>(lt);
+  auto ymd = std::chrono::year_month_day{days};
+
+  auto p = out;
+
+  p = cpydig2(static_cast<uint32_t>(ymd.day()), p);
+  *p++ = '/';
+  p = std::ranges::copy(MONTH[static_cast<uint32_t>(ymd.month()) - 1], p).out;
+  *p++ = '/';
+  p = cpydig4(static_cast<int>(ymd.year()), p);
+  *p++ = ':';
+
+  auto hms = std::chrono::hh_mm_ss{lt - days};
+
+  p = cpydig2(hms.hours().count(), p);
+  *p++ = ':';
+  p = cpydig2(hms.minutes().count(), p);
+  *p++ = ':';
+  p = cpydig2(hms.seconds().count(), p);
+  *p++ = ' ';
+
+  auto sys_info = zt.get_info();
+  auto gmtoff =
+    std::chrono::floor<std::chrono::minutes>(sys_info.offset).count();
+  if (gmtoff >= 0) {
+    *p++ = '+';
+  } else {
+    *p++ = '-';
+    gmtoff = -gmtoff;
+  }
+
+  p = cpydig2(gmtoff / 60, p);
+  p = cpydig2(gmtoff % 60, p);
+
+  *p = '\0';
+
+  return {out, p};
+}
 #else // !defined(HAVE_STD_CHRONO_TIME_ZONE)
 namespace {
 char *iso8601_date(char *out, const std::chrono::system_clock::time_point &tp) {
@@ -522,6 +525,58 @@ format_iso8601_basic(char *out,
   *p = '\0';
   return {out, p};
 }
+
+namespace {
+char *common_log_date(char *out,
+                      const std::chrono::system_clock::time_point &tp) {
+  time_t t =
+    std::chrono::floor<std::chrono::seconds>(tp.time_since_epoch()).count();
+  struct tm tms;
+
+  if (localtime_r(&t, &tms) == nullptr) {
+    return out;
+  }
+
+  auto p = out;
+
+  p = cpydig2(tms.tm_mday, p);
+  *p++ = '/';
+  p = std::ranges::copy(MONTH[tms.tm_mon], p).out;
+  *p++ = '/';
+  p = cpydig4(tms.tm_year + 1900, p);
+  *p++ = ':';
+  p = cpydig2(tms.tm_hour, p);
+  *p++ = ':';
+  p = cpydig2(tms.tm_min, p);
+  *p++ = ':';
+  p = cpydig2(tms.tm_sec, p);
+  *p++ = ' ';
+
+#  ifdef HAVE_STRUCT_TM_TM_GMTOFF
+  auto gmtoff = tms.tm_gmtoff;
+#  else  // !HAVE_STRUCT_TM_TM_GMTOFF
+  auto gmtoff = nghttp2_timegm(&tms) - t;
+#  endif // !HAVE_STRUCT_TM_TM_GMTOFF
+  if (gmtoff >= 0) {
+    *p++ = '+';
+  } else {
+    *p++ = '-';
+    gmtoff = -gmtoff;
+  }
+
+  p = cpydig2(gmtoff / 3600, p);
+  p = cpydig2((gmtoff % 3600) / 60, p);
+
+  return p;
+}
+} // namespace
+
+StringRef format_common_log(char *out,
+                            const std::chrono::system_clock::time_point &tp) {
+  auto p = common_log_date(out, tp);
+  *p = '\0';
+  return {out, p};
+}
 #endif   // !defined(HAVE_STD_CHRONO_TIME_ZONE)
 
 time_t parse_http_date(const StringRef &s) {

src/util.h

@@ -499,14 +499,6 @@ std::string http_date(time_t t);
 // long.  This function returns the one beyond the last position.
 char *http_date(char *res, time_t t);
 
-// Returns given time |t| from epoch in Common Log format (e.g.,
-// 03/Jul/2014:00:19:38 +0900)
-std::string common_log_date(time_t t);
-// Writes given time |t| from epoch in Common Log format into the
-// buffer pointed by |res|.  The buffer must be at least 26 bytes
-// long.  This function returns the one beyond the last position.
-char *common_log_date(char *res, time_t t);
-
 time_t parse_http_date(const StringRef &s);
 
 // Parses time formatted as "MMM DD HH:MM:SS YYYY [GMT]" (e.g., Feb 3
@@ -917,17 +909,18 @@ std::vector<StringRef> split_str(const StringRef &s, char delim, size_t n);
 
 // Writes given time |tp| in Common Log format (e.g.,
 // 03/Jul/2014:00:19:38 +0900) in buffer pointed by |out|.  The buffer
-// must be at least 27 bytes, including terminal NULL byte.  Expected
-// type of |tp| is std::chrono::time_point.  This function returns
-// StringRef wrapping the buffer pointed by |out|, and this string is
-// terminated by NULL.
-template <typename T> StringRef format_common_log(char *out, const T &tp) {
-  auto t =
-    std::chrono::duration_cast<std::chrono::seconds>(tp.time_since_epoch());
-  auto p = common_log_date(out, t.count());
-  *p = '\0';
-  return StringRef{out, p};
-}
+// must be at least 27 bytes, including terminal NULL byte.  This
+// function returns StringRef wrapping the buffer pointed by |out|,
+// and this string is terminated by NULL.
+StringRef format_common_log(char *out,
+                            const std::chrono::system_clock::time_point &tp);
+
+#ifdef HAVE_STD_CHRONO_TIME_ZONE
+// Works like above but with a given time zone.
+StringRef format_common_log(char *out,
+                            const std::chrono::system_clock::time_point &tp,
+                            const std::chrono::time_zone *tz);
+#endif // defined(HAVE_STD_CHRONO_TIME_ZONE)
 
 // Returns given time |tp| in ISO 8601 format (e.g.,
 // 2014-11-15T12:58:24.741Z or 2014-11-15T12:58:24.741+09:00).

src/util_test.cc

@@ -655,6 +655,51 @@ void test_util_parse_http_date(void) {
 }
 
 void test_util_localtime_date(void) {
+  std::array<char, 30> buf;
+
+#ifdef HAVE_STD_CHRONO_TIME_ZONE
+  assert_stdsv_equal(
+    "2001-10-02T00:34:56.123+12:00"sv,
+    util::format_iso8601(buf.data(),
+                         std::chrono::system_clock::time_point(
+                           std::chrono::milliseconds(1001939696123LL)),
+                         std::chrono::locate_zone("Pacific/Auckland"sv)));
+
+  assert_stdsv_equal(
+    "20011002T003456.123+1200"sv,
+    util::format_iso8601_basic(buf.data(),
+                               std::chrono::system_clock::time_point(
+                                 std::chrono::milliseconds(1001939696123LL)),
+                               std::chrono::locate_zone("Pacific/Auckland"sv)));
+
+  assert_stdsv_equal(
+    "02/Oct/2001:00:34:56 +1200"sv,
+    util::format_common_log(
+      buf.data(),
+      std::chrono::system_clock::time_point(std::chrono::seconds(1001939696)),
+      std::chrono::locate_zone("Pacific/Auckland"sv)));
+
+  assert_stdsv_equal(
+    "2001-10-01T12:34:56.123Z"sv,
+    util::format_iso8601(buf.data(),
+                         std::chrono::system_clock::time_point(
+                           std::chrono::milliseconds(1001939696123LL)),
+                         std::chrono::locate_zone("GMT"sv)));
+
+  assert_stdsv_equal(
+    "20011001T123456.123Z"sv,
+    util::format_iso8601_basic(buf.data(),
+                               std::chrono::system_clock::time_point(
+                                 std::chrono::milliseconds(1001939696123LL)),
+                               std::chrono::locate_zone("GMT"sv)));
+
+  assert_stdsv_equal(
+    "01/Oct/2001:12:34:56 +0000"sv,
+    util::format_common_log(
+      buf.data(),
+      std::chrono::system_clock::time_point(std::chrono::seconds(1001939696)),
+      std::chrono::locate_zone("GMT"sv)));
+#else // !defined(HAVE_STD_CHRONO_TIME_ZONE)
   auto tz = getenv("TZ");
   if (tz) {
     tz = strdup(tz);
@@ -666,60 +711,23 @@ void test_util_localtime_date(void) {
 #  endif // !__linux__
   tzset();
 
-  assert_stdstring_equal("02/Oct/2001:00:34:56 +1200",
-                         util::common_log_date(1001939696));
+  assert_stdsv_equal(
+    "2001-10-02T00:34:56.123+12:00"sv,
+    util::format_iso8601(buf.data(),
+                         std::chrono::system_clock::time_point(
+                           std::chrono::milliseconds(1001939696123LL))));
 
-  std::array<char, 27> common_buf;
+  assert_stdsv_equal(
+    "20011002T003456.123+1200"sv,
+    util::format_iso8601_basic(buf.data(),
+                               std::chrono::system_clock::time_point(
+                                 std::chrono::milliseconds(1001939696123LL))));
 
-  assert_stdsv_equal("02/Oct/2001:00:34:56 +1200"sv,
-                     util::format_common_log(
-                       common_buf.data(), std::chrono::system_clock::time_point(
+  assert_stdsv_equal(
+    "02/Oct/2001:00:34:56 +1200"sv,
+    util::format_common_log(buf.data(), std::chrono::system_clock::time_point(
                                           std::chrono::seconds(1001939696))));
 
-  std::array<char, 30> iso8601_buf;
-
-#ifdef HAVE_STD_CHRONO_TIME_ZONE
-  assert_stdsv_equal(
-    "2001-10-02T00:34:56.123+12:00"sv,
-    util::format_iso8601(iso8601_buf.data(),
-                         std::chrono::system_clock::time_point(
-                           std::chrono::milliseconds(1001939696123LL)),
-                         std::chrono::locate_zone("Pacific/Auckland"sv)));
-
-  assert_stdsv_equal(
-    "20011002T003456.123+1200"sv,
-    util::format_iso8601_basic(iso8601_buf.data(),
-                               std::chrono::system_clock::time_point(
-                                 std::chrono::milliseconds(1001939696123LL)),
-                               std::chrono::locate_zone("Pacific/Auckland"sv)));
-
-  assert_stdsv_equal(
-    "2001-10-01T12:34:56.123Z"sv,
-    util::format_iso8601(iso8601_buf.data(),
-                         std::chrono::system_clock::time_point(
-                           std::chrono::milliseconds(1001939696123LL)),
-                         std::chrono::locate_zone("GMT"sv)));
-
-  assert_stdsv_equal(
-    "20011001T123456.123Z"sv,
-    util::format_iso8601_basic(iso8601_buf.data(),
-                               std::chrono::system_clock::time_point(
-                                 std::chrono::milliseconds(1001939696123LL)),
-                               std::chrono::locate_zone("GMT"sv)));
-#else  // !defined(HAVE_STD_CHRONO_TIME_ZONE)
-  assert_stdsv_equal(
-    "2001-10-02T00:34:56.123+12:00"sv,
-    util::format_iso8601(iso8601_buf.data(),
-                         std::chrono::system_clock::time_point(
-                           std::chrono::milliseconds(1001939696123LL))));
-
-  assert_stdsv_equal(
-    "20011002T003456.123+1200"sv,
-    util::format_iso8601_basic(iso8601_buf.data(),
-                               std::chrono::system_clock::time_point(
-                                 std::chrono::milliseconds(1001939696123LL))));
-#endif // !defined(HAVE_STD_CHRONO_TIME_ZONE)
-
   if (tz) {
     setenv("TZ", tz, 1);
     free(tz);
@@ -727,6 +735,7 @@ void test_util_localtime_date(void) {
     unsetenv("TZ");
   }
   tzset();
+#endif   // !defined(HAVE_STD_CHRONO_TIME_ZONE)
 }
 
 void test_util_get_uint64(void) {