Enable CultureInfo netstandard 1.7 APIs on Linux (#7811)

* Enable CultureInfo netstandard 1.7 APIs on Linux

* fix spaces

* Use Array.Empty<CultureInfo> instead of CultureInfo[0]

2 files changed, 76 insertions, 5 deletions

diff --git a/src/corefx/System.Globalization.Native/locale.cpp b/src/corefx/System.Globalization.Native/locale.cpp
index 0a85ae1873..951179d321 100644
--- a/src/corefx/System.Globalization.Native/locale.cpp
+++ b/src/corefx/System.Globalization.Native/locale.cpp
@@ -148,6 +148,56 @@ const char* DetectDefaultLocaleName()
     return uloc_getDefault();
 }
 
+// GlobalizationNative_GetLocales gets all locale names and store it in the value buffer
+// in case of success, it returns the count of the characters stored in value buffer  
+// in case of failure, it returns negative number.
+// if the input value buffer is null, it returns the length needed to store the 
+// locale names list.
+// if the value is not null, it fills the value with locale names separated by the length 
+// of each name. 
+extern "C" int32_t GlobalizationNative_GetLocales(UChar *value, int32_t valueLength)
+{
+    int32_t totalLength = 0;
+    int32_t index = 0;
+    int32_t localeCount = uloc_countAvailable();
+    
+    if (localeCount <=  0)
+        return -1; // failed
+    
+    for (int32_t i = 0; i < localeCount; i++)
+    {
+        const char *pLocaleName = uloc_getAvailable(i);
+        if (pLocaleName[0] == 0) // unexpected empty name
+            return -2;
+        
+        int32_t localeNameLength = strlen(pLocaleName);
+        
+        totalLength += localeNameLength + 1; // add 1 for the name length
+        
+        if (value != nullptr)
+        {
+            if (totalLength > valueLength)
+                return -3;
+            
+            value[index++] = (UChar) localeNameLength;
+            
+            for (int j=0; j<localeNameLength; j++)
+            {
+                if (pLocaleName[j] == '_') // fix the locale name  
+                {
+                    value[index++] = (UChar) '-';
+                }
+                else
+                {
+                    value[index++] = (UChar) pLocaleName[j];
+                }
+            }
+        }
+    }
+    
+    return totalLength;
+}
+
 extern "C" int32_t GlobalizationNative_GetLocaleName(const UChar* localeName, UChar* value, int32_t valueLength)
 {
     UErrorCode status = U_ZERO_ERROR;
diff --git a/src/corefx/System.Globalization.Native/localeStringData.cpp b/src/corefx/System.Globalization.Native/localeStringData.cpp
index 54ef8f02f1..b8eaa307c7 100644
--- a/src/corefx/System.Globalization.Native/localeStringData.cpp
+++ b/src/corefx/System.Globalization.Native/localeStringData.cpp
@@ -37,7 +37,8 @@ enum LocaleStringData : int32_t
     PMDesignator = 0x00000029,
     PositiveSign = 0x00000050,
     NegativeSign = 0x00000051,
-    Iso639LanguageName = 0x00000059,
+    Iso639LanguageTwoLetterName = 0x00000059,
+    Iso639LanguageThreeLetterName = 0x00000067,
     Iso3166CountryName = 0x0000005A,
     Iso3166CountryName2= 0x00000068,
     NaNSymbol = 0x00000069,
@@ -115,11 +116,11 @@ UErrorCode GetLocaleInfoAmPm(const char* locale, bool am, UChar* value, int32_t
 
 /*
 Function:
-GetLocaleIso639LanguageName
+GetLocaleIso639LanguageTwoLetterName
 
 Gets the language name for a locale (via uloc_getLanguage) and converts the result to UChars
 */
-UErrorCode GetLocaleIso639LanguageName(const char* locale, UChar* value, int32_t valueLength)
+UErrorCode GetLocaleIso639LanguageTwoLetterName(const char* locale, UChar* value, int32_t valueLength)
 {
     UErrorCode status = U_ZERO_ERROR;
     int32_t length = uloc_getLanguage(locale, nullptr, 0, &status);
@@ -139,6 +140,23 @@ UErrorCode GetLocaleIso639LanguageName(const char* locale, UChar* value, int32_t
 
 /*
 Function:
+GetLocaleIso639LanguageThreeLetterName
+
+Gets the language name for a locale (via uloc_getISO3Language) and converts the result to UChars
+*/
+UErrorCode GetLocaleIso639LanguageThreeLetterName(const char* locale, UChar* value, int32_t valueLength)
+{
+    const char *isoLanguage = uloc_getISO3Language(locale);
+    if (isoLanguage[0] == 0)
+    {
+        return U_ILLEGAL_ARGUMENT_ERROR;
+    }
+    
+    return u_charsToUChars_safe(isoLanguage, value, valueLength);
+}
+
+/*
+Function:
 GetLocaleIso3166CountryName
 
 Gets the country name for a locale (via uloc_getCountry) and converts the result to UChars
@@ -315,8 +333,11 @@ extern "C" int32_t GlobalizationNative_GetLocaleInfoString(
         case NegativeSign:
             status = GetLocaleInfoDecimalFormatSymbol(locale, UNUM_MINUS_SIGN_SYMBOL, value, valueLength);
             break;
-        case Iso639LanguageName:
-            status = GetLocaleIso639LanguageName(locale, value, valueLength);
+        case Iso639LanguageTwoLetterName:
+            status = GetLocaleIso639LanguageTwoLetterName(locale, value, valueLength);
+            break;
+        case Iso639LanguageThreeLetterName:
+            status = GetLocaleIso639LanguageThreeLetterName(locale, value, valueLength);
             break;
         case Iso3166CountryName:
             status = GetLocaleIso3166CountryName(locale, value, valueLength);