Use DirectByteBuffer

Seems my mimalloc(I use it as Android's system allocator) doesn't like release memory to system since I replace MADV_DONTNEED with MADV_FREE
https://github.com/AcmeUI/android_external_mimalloc
but there is no memleak I sure

app/src/main/cpp/archive.c

@@ -250,8 +250,8 @@ Java_com_hippo_UriArchiveAccessor_openArchive(JNIEnv *env, jobject thiz, jint fd
     return r;
 }
 
-JNIEXPORT jint JNICALL
-Java_com_hippo_UriArchiveAccessor_extractToMemfd(JNIEnv *env, jobject thiz, jint index) {
+JNIEXPORT jobject JNICALL
+Java_com_hippo_UriArchiveAccessor_extractToByteBuffer(JNIEnv *env, jobject thiz, jint index) {
     EH_UNUSED(env);
     EH_UNUSED(thiz);
     archive_ctx *ctx = NULL;
@@ -259,13 +259,23 @@ Java_com_hippo_UriArchiveAccessor_extractToMemfd(JNIEnv *env, jobject thiz, jint
     ret = archive_get_ctx(&ctx, index);
     if (ret)
         return 0;
-    int memfd = syscall(SYS_memfd_create, "ArchiveMemFD", 0);
-    ret = archive_read_data_into_fd(ctx->arc, memfd);
+    long long size = archive_entry_size(ctx->entry);
+    void *buffer = malloc(size);
+    if (!buffer) {
+        ctx->using = 0;
+        LOGE("Allocate buffer for decompression failed:ENOMEM");
+        return 0;
+    }
+    ret = archive_read_data(ctx->arc, buffer, size);
     ctx->using = 0;
+    if (ret == size)
+        return (*env)->NewDirectByteBuffer(env, buffer, size);
+    if (ret != size)
+        LOGE("%s", "No enough data read, WTF?");
     if (ret < 0)
         LOGE("%s%s", "Archive read failed:", archive_error_string(ctx->arc));
-    lseek64(memfd, 0, SEEK_SET);
-    return memfd;
+    free(buffer);
+    return 0;
 }
 
 JNIEXPORT void JNICALL
@@ -344,4 +354,10 @@ Java_com_hippo_UriArchiveAccessor_extractToFd(JNIEnv *env, jobject thiz, jint in
         archive_read_data_into_fd(ctx->arc, fd);
         ctx->using = 0;
     }
+}
+
+JNIEXPORT void JNICALL
+Java_com_hippo_UriArchiveAccessor_releaseByteBuffer(JNIEnv *env, jobject thiz, jobject buffer) {
+    void *addr = (*env)->GetDirectBufferAddress(env, buffer);
+    free(addr);
 }

app/src/main/java/com/hippo/UriArchiveAccessor.kt

@@ -19,6 +19,7 @@ package com.hippo
 
 import android.content.Context
 import android.net.Uri
+import java.nio.ByteBuffer
 
 class UriArchiveAccessor(ctx: Context, uri: Uri) {
     val pfd by lazy { ctx.contentResolver.openFileDescriptor(uri, "r")!! }
@@ -27,7 +28,9 @@ class UriArchiveAccessor(ctx: Context, uri: Uri) {
     }
 
     private external fun openArchive(fd: Int, size: Long): Int
-    external fun extractToMemfd(index: Int): Int
+    external fun extractToByteBuffer(index: Int): ByteBuffer
+
+    external fun releaseByteBuffer(buffer: ByteBuffer)
     external fun extractToFd(index: Int, fd: Int)
     external fun getFilename(index: Int): String
     external fun needPassword(): Boolean

app/src/main/java/com/hippo/ehviewer/gallery/ArchiveGalleryProvider.java

@@ -39,6 +39,7 @@ import com.hippo.yorozuya.thread.PriorityThread;
 import java.io.FileInputStream;
 import java.io.FileOutputStream;
 import java.io.IOException;
+import java.nio.ByteBuffer;
 import java.util.Iterator;
 import java.util.LinkedHashMap;
 import java.util.Map;
@@ -53,7 +54,7 @@ public class ArchiveGalleryProvider extends GalleryProvider2 {
     public static PVLock pv = new PVLock(0);
     private final UriArchiveAccessor archiveAccessor;
     private final Stack<Integer> requests = new Stack<>();
-    private final LinkedHashMap<Integer, Integer> streams = new LinkedHashMap<>();
+    private final LinkedHashMap<Integer, ByteBuffer> streams = new LinkedHashMap<>();
     private final Thread[] decodeThread = new Thread[]{
             new Thread(new DecodeTask()),
             new Thread(new DecodeTask()),
@@ -299,10 +300,10 @@ public class ArchiveGalleryProvider extends GalleryProvider2 {
                     }
                 }
 
-                int fd = archiveAccessor.extractToMemfd(index);
+                ByteBuffer buffer = archiveAccessor.extractToByteBuffer(index);
 
                 synchronized (streams) {
-                    streams.put(index, fd);
+                    streams.put(index, buffer);
                     streams.notify();
                 }
             }
@@ -314,7 +315,7 @@ public class ArchiveGalleryProvider extends GalleryProvider2 {
         public void run() {
             while (!Thread.currentThread().isInterrupted()) {
                 int index;
-                int fd;
+                ByteBuffer buffer;
                 synchronized (streams) {
                     if (streams.isEmpty()) {
                         try {
@@ -325,15 +326,18 @@ public class ArchiveGalleryProvider extends GalleryProvider2 {
                         continue;
                     }
 
-                    Iterator<Map.Entry<Integer, Integer>> iterator = streams.entrySet().iterator();
-                    Map.Entry<Integer, Integer> entry = iterator.next();
+                    Iterator<Map.Entry<Integer, ByteBuffer>> iterator = streams.entrySet().iterator();
+                    Map.Entry<Integer, ByteBuffer> entry = iterator.next();
                     iterator.remove();
                     index = entry.getKey();
-                    fd = entry.getValue();
+                    buffer = entry.getValue();
                 }
 
                 Image image;
-                image = Image.decode(new FileInputStream(ParcelFileDescriptor.adoptFd(fd).getFileDescriptor()), false); // we take ownership here since this memfd is anon fd
+                image = Image.decode(buffer, false, () -> {
+                    archiveAccessor.releaseByteBuffer(buffer);
+                    return null;
+                });
                 if (image != null) {
                     notifyPageSucceed(index, image);
                 } else {

app/src/main/java/com/hippo/image/Image.kt

@@ -30,11 +30,13 @@ import android.graphics.drawable.BitmapDrawable
 import android.graphics.drawable.Drawable
 import androidx.core.graphics.drawable.toDrawable
 import java.io.FileInputStream
+import java.nio.ByteBuffer
 import java.nio.channels.FileChannel
 
 class Image private constructor(
     source: Source?, drawable: Drawable? = null,
-    val hardware: Boolean = true
+    val hardware: Boolean = true,
+    val release: () -> Unit? = {}
 ) {
     internal var mObtainedDrawable: Drawable?
     private var mBitmap: Bitmap? = null
@@ -72,6 +74,7 @@ class Image private constructor(
         mObtainedDrawable = null
         mBitmap?.recycle()
         mBitmap = null
+        release()
     }
 
     private fun prepareBitmap() {
@@ -155,6 +158,14 @@ class Image private constructor(
             return Image(src, hardware = hardware)
         }
 
+        @JvmStatic
+        fun decode(buffer: ByteBuffer, hardware: Boolean = true, release: () -> Unit? = {}): Image {
+            val src = ImageDecoder.createSource(buffer)
+            return Image(src, hardware = hardware) {
+                release()
+            }
+        }
+
         @JvmStatic
         fun create(bitmap: Bitmap): Image {
             return Image(null, bitmap.toDrawable(Resources.getSystem()), false)