Cherry pick PR #1615: Add SetTimeZone API as a starboard extension (#…

…1887)

Refer to the original PR: #1615

In order to test SbTimeZoneGetCurrent(), we need to set a time zone
first. Here we add a new time zone API as a starboard extension to set
time zone. We start with Linux implementation. Will have follow up PR to
add implementations for all first party platforms. This will help catch
the issue if a platform forget to implement SbTimeZoneGetCurrent() which
always return 0.

b/300108997

Co-authored-by: Sherry Zhou <[email protected]>

starboard/extension/extension_test.cc

@@ -27,6 +27,7 @@
 #include "starboard/extension/memory_mapped_file.h"
 #include "starboard/extension/platform_info.h"
 #include "starboard/extension/platform_service.h"
+#include "starboard/extension/time_zone.h"
 #include "starboard/extension/updater_notification.h"
 #include "starboard/extension/url_fetcher_observer.h"
 #include "starboard/system.h"
@@ -438,5 +439,25 @@ TEST(ExtensionTest, PlatformInfo) {
       << "Extension struct should be a singleton";
 }
 
+TEST(ExtensionTest, TimeZone) {
+  typedef StarboardExtensionTimeZoneApi ExtensionApi;
+  const char* kExtensionName = kStarboardExtensionTimeZoneName;
+
+  const ExtensionApi* extension_api =
+      static_cast<const ExtensionApi*>(SbSystemGetExtension(kExtensionName));
+  if (!extension_api) {
+    return;
+  }
+
+  EXPECT_STREQ(extension_api->name, kExtensionName);
+  EXPECT_EQ(extension_api->version, 1u);
+  EXPECT_NE(extension_api->SetTimeZone, nullptr);
+
+  const ExtensionApi* second_extension_api =
+      static_cast<const ExtensionApi*>(SbSystemGetExtension(kExtensionName));
+  EXPECT_EQ(second_extension_api, extension_api)
+      << "Extension struct should be a singleton";
+}
+
 }  // namespace extension
 }  // namespace starboard

starboard/extension/time_zone.h

@@ -0,0 +1,47 @@
+// Copyright 2023 The Cobalt Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef STARBOARD_EXTENSION_TIME_ZONE_H_
+#define STARBOARD_EXTENSION_TIME_ZONE_H_
+
+#include <stdint.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define kStarboardExtensionTimeZoneName "dev.starboard.extension.TimeZone"
+
+typedef struct StarboardExtensionTimeZoneApi {
+  // Name should be the string |kStarboardExtensionSetTimeZoneName|.
+  // This helps to validate that the extension API is correct.
+  const char* name;
+
+  // This specifies the version of the API that is implemented.
+  uint32_t version;
+
+  // Sets the current time zone to the specified time zone name.
+  // Note: This function should not be called with a NULL or empty
+  // string. It does not actually change the system clock, so it
+  // will not affect the time displayed on the system clock or
+  // used by other system processes.
+  bool (*SetTimeZone)(const char* time_zone_name);
+
+} StarboardExtensionTimeZoneApi;
+
+#ifdef __cplusplus
+}  // extern "C"
+#endif
+
+#endif  // STARBOARD_EXTENSION_TIME_ZONE_H_

starboard/linux/shared/BUILD.gn

@@ -80,6 +80,8 @@ static_library("starboard_platform_sources") {
     "//starboard/linux/shared/system_get_extensions.cc",
     "//starboard/linux/shared/system_get_path.cc",
     "//starboard/linux/shared/system_has_capability.cc",
+    "//starboard/linux/shared/time_zone.cc",
+    "//starboard/linux/shared/time_zone.h",
     "//starboard/shared/alsa/alsa_audio_sink_type.cc",
     "//starboard/shared/alsa/alsa_audio_sink_type.h",
     "//starboard/shared/alsa/alsa_util.cc",

starboard/linux/shared/system_get_extensions.cc

@@ -22,7 +22,9 @@
 #include "starboard/extension/free_space.h"
 #include "starboard/extension/memory_mapped_file.h"
 #include "starboard/extension/platform_service.h"
+#include "starboard/extension/time_zone.h"
 #include "starboard/linux/shared/soft_mic_platform_service.h"
+#include "starboard/linux/shared/time_zone.h"
 #include "starboard/shared/enhanced_audio/enhanced_audio.h"
 #include "starboard/shared/ffmpeg/ffmpeg_demuxer.h"
 #include "starboard/shared/posix/free_space.h"
@@ -74,5 +76,8 @@ const void* SbSystemGetExtension(const char* name) {
     return use_ffmpeg_demuxer ? starboard::shared::ffmpeg::GetFFmpegDemuxerApi()
                               : NULL;
   }
+  if (strcmp(name, kStarboardExtensionTimeZoneName) == 0) {
+    return starboard::shared::GetTimeZoneApi();
+  }
   return NULL;
 }

starboard/linux/shared/time_zone.cc

@@ -0,0 +1,60 @@
+// Copyright 2023 The Cobalt Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "starboard/linux/shared/time_zone.h"
+
+#include "starboard/extension/time_zone.h"
+
+#include <stdlib.h>
+#include <time.h>
+#include <cstring>
+
+#include "starboard/common/log.h"
+
+namespace starboard {
+namespace shared {
+
+namespace {
+
+// Definitions of any functions included as components in the extension
+// are added here.
+
+bool SetTimeZone(const char* time_zone_name) {
+  if (time_zone_name == nullptr || strlen(time_zone_name) == 0) {
+    SB_LOG(ERROR) << "Set time zone failed!";
+    SB_LOG(ERROR) << "Time zone name can't be null or empty string.";
+    return false;
+  }
+  if (setenv("TZ", time_zone_name, 1) != 0) {
+    SB_LOG(WARNING) << "Set time zone failed!";
+    return false;
+  }
+  tzset();
+  return true;
+}
+
+const StarboardExtensionTimeZoneApi kTimeZoneApi = {
+    kStarboardExtensionTimeZoneName,
+    1,  // API version that's implemented.
+    &SetTimeZone,
+};
+
+}  // namespace
+
+const void* GetTimeZoneApi() {
+  return &kTimeZoneApi;
+}
+
+}  // namespace shared
+}  // namespace starboard

starboard/linux/shared/time_zone.h

@@ -0,0 +1,27 @@
+// Copyright 2023 The Cobalt Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef STARBOARD_LINUX_SHARED_TIME_ZONE_H_
+#define STARBOARD_LINUX_SHARED_TIME_ZONE_H_
+
+// Omit namespace linux due to symbol name conflict.
+namespace starboard {
+namespace shared {
+
+const void* GetTimeZoneApi();
+
+}  // namespace shared
+}  // namespace starboard
+
+#endif  // STARBOARD_LINUX_SHARED_TIME_ZONE_H_

starboard/nplb/time_zone_get_current_test.cc

@@ -12,7 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+#include "starboard/extension/time_zone.h"
 #include "starboard/nplb/time_constants.h"
+#include "starboard/system.h"
 #include "starboard/time_zone.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ -34,9 +36,64 @@ TEST(SbTimeZoneGetCurrentTest, IsKindOfSane) {
   // ... and +24 hours from the Prime Meridian, inclusive
   EXPECT_LE(zone, 24 * 60);
 
-  if (zone == 0) {
-    SB_LOG(WARNING) << "SbTimeZoneGetCurrent() returns 0. This is only correct "
-                       "if the current time zone is the same as UTC";
+  static auto const* time_zone_extension =
+      static_cast<const StarboardExtensionTimeZoneApi*>(
+          SbSystemGetExtension(kStarboardExtensionTimeZoneName));
+  if (time_zone_extension) {
+    ASSERT_STREQ(time_zone_extension->name, kStarboardExtensionTimeZoneName);
+    ASSERT_EQ(time_zone_extension->version, 1u);
+    time_zone_extension->SetTimeZone("UTC");
+    zone = SbTimeZoneGetCurrent();
+    EXPECT_EQ(zone, 0);
+
+    // Atlantic time zone, UTC−04:00
+    time_zone_extension->SetTimeZone("America/Puerto_Rico");
+    zone = SbTimeZoneGetCurrent();
+    EXPECT_EQ(zone, 240);
+
+    // Eastern time zone, UTC−05:00
+    time_zone_extension->SetTimeZone("America/New_York");
+    zone = SbTimeZoneGetCurrent();
+    EXPECT_EQ(zone, 300);
+
+    time_zone_extension->SetTimeZone("US/Eastern");
+    zone = SbTimeZoneGetCurrent();
+    EXPECT_EQ(zone, 300);
+
+    // Central time zone, UTC−06:00
+    time_zone_extension->SetTimeZone("America/Chicago");
+    zone = SbTimeZoneGetCurrent();
+    EXPECT_EQ(zone, 360);
+
+    // Mountain time zone, UTC−07:00
+    time_zone_extension->SetTimeZone("US/Mountain");
+    zone = SbTimeZoneGetCurrent();
+    EXPECT_EQ(zone, 420);
+
+    // Pacific time zone, UTC-08:00
+    time_zone_extension->SetTimeZone("US/Pacific");
+    zone = SbTimeZoneGetCurrent();
+    EXPECT_EQ(zone, 480);
+
+    // Alaska time zone, UTC-09:00
+    time_zone_extension->SetTimeZone("US/Alaska");
+    zone = SbTimeZoneGetCurrent();
+    EXPECT_EQ(zone, 540);
+
+    // Hawaii-Aleutian time zone, UTC-10:00
+    time_zone_extension->SetTimeZone("Pacific/Honolulu");
+    zone = SbTimeZoneGetCurrent();
+    EXPECT_EQ(zone, 600);
+
+    // American Samoa time zone, UTC-11:00
+    time_zone_extension->SetTimeZone("US/Samoa");
+    zone = SbTimeZoneGetCurrent();
+    EXPECT_EQ(zone, 660);
+
+    // American Samoa time zone, UTC+10:00
+    time_zone_extension->SetTimeZone("Pacific/Guam");
+    zone = SbTimeZoneGetCurrent();
+    EXPECT_EQ(zone, -600);
   }
 }