Fall back to "tl" if "fil" is absent.

For JB-MR1, there was a hack that used "tl" where
we really meant "fil" because ICU didn't have localizations
for "fil". This has now been fixed, and we now support 3 letter
language codes for AAPT so we can use "fil" where required.

For the benefit of apps that need to target older platforms,
we fall back to "tl" if the app has assets for "tl" and the
resource locale is "fil".

See bugs 7291355, 7207176 and 8049507 for more context.

Change-Id: I1ac8502525f99b40f9091d5efd2df33518d47a41

libs/androidfw/AssetManager.cpp

@@ -347,6 +347,15 @@ void AssetManager::setLocale(const char* locale)
     setLocaleLocked(locale);
 }
 
+
+static const char kFilPrefix[] = "fil";
+static const char kTlPrefix[] = "tl";
+
+// The sizes of the prefixes, excluding the 0 suffix.
+// char.
+static const int kFilPrefixLen = sizeof(kFilPrefix) - 1;
+static const int kTlPrefixLen = sizeof(kTlPrefix) - 1;
+
 void AssetManager::setLocaleLocked(const char* locale)
 {
     if (mLocale != NULL) {
@@ -355,8 +364,44 @@ void AssetManager::setLocaleLocked(const char* locale)
         //mZipSet.purgeLocale();
         delete[] mLocale;
     }
-    mLocale = strdupNew(locale);
 
+
+    // If we're attempting to set a locale that starts with "fil",
+    // we should convert it to "tl" for backwards compatibility since
+    // we've been using "tl" instead of "fil" prior to L.
+    //
+    // If the resource table already has entries for "fil", we use that
+    // instead of attempting a fallback.
+    if (strncmp(locale, kFilPrefix, kFilPrefixLen) == 0) {
+        Vector<String8> locales;
+        getLocales(&locales);
+        const size_t localesSize = locales.size();
+        bool hasFil = false;
+        for (size_t i = 0; i < localesSize; ++i) {
+            if (locales[i].find(kFilPrefix) == 0) {
+                hasFil = true;
+                break;
+            }
+        }
+
+
+        if (!hasFil) {
+            const size_t newLocaleLen = strlen(locale);
+            // This isn't a bug. We really do want mLocale to be 1 byte
+            // shorter than locale, because we're replacing "fil-" with
+            // "tl-".
+            mLocale = new char[newLocaleLen];
+            // Copy over "tl".
+            memcpy(mLocale, kTlPrefix, kTlPrefixLen);
+            // Copy the rest of |locale|, including the terminating '\0'.
+            memcpy(mLocale + kTlPrefixLen, locale + kFilPrefixLen,
+                   newLocaleLen - kFilPrefixLen + 1);
+            updateResourceParamsLocked();
+            return;
+        }
+    }
+
+    mLocale = strdupNew(locale);
     updateResourceParamsLocked();
 }
 
@@ -741,6 +786,16 @@ void AssetManager::getLocales(Vector<String8>* locales) const
     if (res != NULL) {
         res->getLocales(locales);
     }
+
+    const size_t numLocales = locales->size();
+    for (size_t i = 0; i < numLocales; ++i) {
+        const String8& localeStr = locales->itemAt(i);
+        if (localeStr.find(kTlPrefix) == 0) {
+            String8 replaced("fil");
+            replaced += (localeStr.string() + kTlPrefixLen);
+            locales->editItemAt(i) = replaced;
+        }
+    }
 }
 
 /*