TimeZoneInfo.DisplayName values are not localized on Linux

Fixed by calling ICU's ucal_getTimeZoneDisplayName to read the display names for the current locale.

Fix https://github.com/dotnet/corefx/issues/2748

3 files changed, 84 insertions, 45 deletions

diff --git a/src/corefx/System.Globalization.Native/calendarData.cpp b/src/corefx/System.Globalization.Native/calendarData.cpp
index fb035a9692..f91cc0cb57 100644
--- a/src/corefx/System.Globalization.Native/calendarData.cpp
+++ b/src/corefx/System.Globalization.Native/calendarData.cpp
@@ -9,6 +9,7 @@
 #include "config.h"
 #include "locale.hpp"
 #include "holders.h"
+#include "errors.h"
 
 #define GREGORIAN_NAME "gregorian"
 #define JAPANESE_NAME "japanese"
@@ -82,43 +83,11 @@ enum CalendarDataType : int32_t
     AbbrevEraNames = 14,
 };
 
-/*
-* These values should be kept in sync with
-* System.Globalization.CalendarDataResult
-*/
-enum CalendarDataResult : int32_t
-{
-    Success = 0,
-    UnknownError = 1,
-    InsufficentBuffer = 2,
-};
-
 // the function pointer definition for the callback used in EnumCalendarInfo
 typedef void (*EnumCalendarInfoCallback)(const UChar*, const void*);
 
 /*
 Function:
-GetCalendarDataResult
-
-Converts a UErrorCode to a CalendarDataResult.
-*/
-CalendarDataResult GetCalendarDataResult(UErrorCode err)
-{
-    if (U_SUCCESS(err))
-    {
-        return Success;
-    }
-
-    if (err == U_BUFFER_OVERFLOW_ERROR)
-    {
-        return InsufficentBuffer;
-    }
-
-    return UnknownError;
-}
-
-/*
-Function:
 GetCalendarName
 
 Gets the associated ICU calendar name for the CalendarId.
@@ -247,18 +216,18 @@ GetMonthDayPattern
 
 Gets the Month-Day DateTime pattern for the specified locale.
 */
-CalendarDataResult GetMonthDayPattern(const char* locale, UChar* sMonthDay, int32_t stringCapacity)
+ResultCode GetMonthDayPattern(const char* locale, UChar* sMonthDay, int32_t stringCapacity)
 {
     UErrorCode err = U_ZERO_ERROR;
     UDateTimePatternGenerator* pGenerator = udatpg_open(locale, &err);
     UDateTimePatternGeneratorHolder generatorHolder(pGenerator, err);
 
     if (U_FAILURE(err))
-        return GetCalendarDataResult(err);
+        return GetResultCode(err);
 
     udatpg_getBestPattern(pGenerator, UDAT_MONTH_DAY_UCHAR, -1, sMonthDay, stringCapacity, &err);
 
-    return GetCalendarDataResult(err);
+    return GetResultCode(err);
 }
 
 /*
@@ -267,8 +236,7 @@ GetNativeCalendarName
 
 Gets the native calendar name.
 */
-CalendarDataResult
-GetNativeCalendarName(const char* locale, CalendarId calendarId, UChar* nativeName, int32_t stringCapacity)
+ResultCode GetNativeCalendarName(const char* locale, CalendarId calendarId, UChar* nativeName, int32_t stringCapacity)
 {
     UErrorCode err = U_ZERO_ERROR;
     ULocaleDisplayNames* pDisplayNames = uldn_open(locale, ULDN_STANDARD_NAMES, &err);
@@ -276,7 +244,7 @@ GetNativeCalendarName(const char* locale, CalendarId calendarId, UChar* nativeNa
 
     uldn_keyValueDisplayName(pDisplayNames, "calendar", GetCalendarName(calendarId), nativeName, stringCapacity, &err);
 
-    return GetCalendarDataResult(err);
+    return GetResultCode(err);
 }
 
 /*
@@ -286,7 +254,7 @@ GetCalendarInfo
 Gets a single string of calendar information by filling the result parameter
 with the requested value.
 */
-extern "C" CalendarDataResult GlobalizationNative_GetCalendarInfo(
+extern "C" ResultCode GlobalizationNative_GetCalendarInfo(
     const UChar* localeName, CalendarId calendarId, CalendarDataType dataType, UChar* result, int32_t resultCapacity)
 {
     UErrorCode err = U_ZERO_ERROR;
@@ -542,9 +510,9 @@ The context parameter is passed through to the callback along with each string.
 */
 extern "C" int32_t GlobalizationNative_EnumCalendarInfo(
                         EnumCalendarInfoCallback callback, 
-                        const UChar* localeName, 
-                        CalendarId calendarId, 
-                        CalendarDataType dataType, 
+                        const UChar* localeName,
+                        CalendarId calendarId,
+                        CalendarDataType dataType,
                         const void* context)
 {
     UErrorCode err = U_ZERO_ERROR;
diff --git a/src/corefx/System.Globalization.Native/errors.h b/src/corefx/System.Globalization.Native/errors.h
new file mode 100644
index 0000000000..2bfbdb2ba1
--- /dev/null
+++ b/src/corefx/System.Globalization.Native/errors.h
@@ -0,0 +1,36 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+#pragma once
+
+#include <unicode/utypes.h>
+
+/*
+* These values should be kept in sync with
+* Interop.GlobalizationInterop.ResultCode
+*/
+enum ResultCode : int32_t
+{
+    Success = 0,
+    UnknownError = 1,
+    InsufficentBuffer = 2,
+};
+
+/*
+Converts a UErrorCode to a ResultCode.
+*/
+static ResultCode GetResultCode(UErrorCode err)
+{
+    if (err == U_BUFFER_OVERFLOW_ERROR || err == U_STRING_NOT_TERMINATED_WARNING)
+    {
+        return InsufficentBuffer;
+    }
+
+    if (U_SUCCESS(err))
+    {
+        return Success;
+    }
+
+    return UnknownError;
+}
diff --git a/src/corefx/System.Globalization.Native/timeZoneInfo.cpp b/src/corefx/System.Globalization.Native/timeZoneInfo.cpp
index 025bccdb09..d0e01e5ce6 100644
--- a/src/corefx/System.Globalization.Native/timeZoneInfo.cpp
+++ b/src/corefx/System.Globalization.Native/timeZoneInfo.cpp
@@ -5,11 +5,13 @@
 
 #include <stdint.h>
 #include <unistd.h>
+#include <unicode/ucal.h>
 
-/*
-Function:
-ReadLink
+#include "locale.hpp"
+#include "holders.h"
+#include "errors.h"
 
+/*
 Gets the symlink value for the path.
 */
 extern "C" int32_t GlobalizationNative_ReadLink(const char* path, char* result, size_t resultCapacity)
@@ -22,3 +24,36 @@ extern "C" int32_t GlobalizationNative_ReadLink(const char* path, char* result,
     result[r] = '\0';
     return true;
 }
+
+/*
+These values should be kept in sync with the managed Interop.GlobalizationInterop.TimeZoneDisplayNameType enum.
+*/
+enum TimeZoneDisplayNameType : int32_t
+{
+    Generic = 0,
+    Standard = 1,
+    DaylightSavings = 2,
+};
+
+/*
+Gets the localized display name for the specified time zone.
+*/
+extern "C" ResultCode GlobalizationNative_GetTimeZoneDisplayName(
+    const UChar* localeName, const UChar* timeZoneId, TimeZoneDisplayNameType type, UChar* result, int32_t resultLength)
+{
+    UErrorCode err = U_ZERO_ERROR;
+    char locale[ULOC_FULLNAME_CAPACITY];
+    GetLocale(localeName, locale, ULOC_FULLNAME_CAPACITY, false, &err);
+
+    int32_t timeZoneIdLength = -1; // timeZoneId is NULL-terminated
+    UCalendar* calendar = ucal_open(timeZoneId, timeZoneIdLength, locale, UCAL_DEFAULT, &err);
+    UCalendarHolder calendarHolder(calendar, err);
+
+    // TODO (https://github.com/dotnet/corefx/issues/5741): need to support Generic names, but ICU "C" api
+    // has no public option for this. For now, just use the ICU standard name for both Standard and Generic
+    // (which is the same behavior on Windows with the mincore TIME_ZONE_INFORMATION APIs).
+    ucal_getTimeZoneDisplayName(
+        calendar, type == DaylightSavings ? UCAL_DST : UCAL_STANDARD, locale, result, resultLength, &err);
+
+    return GetResultCode(err);
+}