Merge "Do not crash if setSystemFont is called twice."

import android.annotation.IntRange;

import android.annotation.NonNull;

import android.annotation.Nullable;

import android.annotation.UiThread;

import android.compat.annotation.UnsupportedAppUsage;

import android.content.res.AssetManager;

import android.graphics.fonts.Font;

    static final Map<String, Typeface> sSystemFontMap = new HashMap<>();

    // DirectByteBuffer object to hold sSystemFontMap's backing memory mapping.

    @GuardedBy("SYSTEM_FONT_MAP_LOCK")

    static ByteBuffer sSystemFontMapBuffer = null;

    static SharedMemory sSystemFontMapSharedMemory = null;

    // Lock to guard sSystemFontMap and derived default or public typefaces.

    // sStyledCacheLock may be held while this lock is held. Holding them in the reverse order may

     * per process.

     */

    /** @hide */

    public static void setSystemFontMap(SharedMemory sharedMemory)

    @UiThread

    public static void setSystemFontMap(@Nullable SharedMemory sharedMemory)

            throws IOException, ErrnoException {

        if (sSystemFontMapBuffer != null) {

            // Apps can re-send BIND_APPLICATION message from their code. This is a work around to

            // detect it and avoid crashing.

            if (sharedMemory == null || sharedMemory == sSystemFontMapSharedMemory) {

                return;

            }

            throw new UnsupportedOperationException(

                    "Once set, buffer-based system font map cannot be updated");

        }

        sSystemFontMapSharedMemory = sharedMemory;

        Trace.traceBegin(Trace.TRACE_TAG_GRAPHICS, "setSystemFontMap");

        try {

            if (sharedMemory == null) {

                // FontManagerService is not started. This may happen in FACTORY_TEST_LOW_LEVEL

                // mode for example.

                loadPreinstalledSystemFontMap();

                return;

            }

            sSystemFontMapBuffer = sharedMemory.mapReadOnly().order(ByteOrder.BIG_ENDIAN);

            Map<String, Typeface> systemFontMap = deserializeFontMap(sSystemFontMapBuffer);

            setSystemFontMap(systemFontMap);

                SharedMemory.unmap(sSystemFontMapBuffer);

            }

            sSystemFontMapBuffer = null;

            sSystemFontMapSharedMemory = null;

        }

    }