Implement new ExternalImage and image chunk strategy

mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/QQAndroidBot.common.kt

@@ -50,7 +50,6 @@ import net.mamoe.mirai.qqandroid.network.protocol.packet.list.FriendList
 import net.mamoe.mirai.qqandroid.utils.MiraiPlatformUtils
 import net.mamoe.mirai.qqandroid.utils.encodeToString
 import net.mamoe.mirai.qqandroid.utils.io.serialization.toByteArray
-import net.mamoe.mirai.qqandroid.utils.toReadPacket
 import net.mamoe.mirai.utils.*
 import kotlin.collections.asSequence
 import kotlin.contracts.ExperimentalContracts
@@ -678,8 +677,8 @@ internal abstract class QQAndroidBotBase constructor(
                         response.proto.uint32UpIp.zip(response.proto.uint32UpPort),
                         response.proto.msgSig,
                         MiraiPlatformUtils.md5(body),
-                        body.toReadPacket(),
-                        body.size.toLong().and(0xFFFF_FFFF), // don't use toLongUnsigned: Overload resolution ambiguity
+                        @Suppress("INVISIBLE_REFERENCE")
+                        net.mamoe.mirai.utils.internal.asReusableInput0(body), // don't use toLongUnsigned: Overload resolution ambiguity
                         "group long message",
                         27
                     )

mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/network/highway/HighwayHelper.kt

@@ -20,22 +20,24 @@ import io.ktor.utils.io.ByteWriteChannel
 import kotlinx.coroutines.InternalCoroutinesApi
 import kotlinx.coroutines.delay
 import kotlinx.coroutines.flow.collect
-import kotlinx.coroutines.io.ByteReadChannel
 import kotlinx.coroutines.isActive
 import kotlinx.coroutines.withTimeoutOrNull
-import kotlinx.io.InputStream
-import kotlinx.io.core.Input
 import kotlinx.io.core.discardExact
-import kotlinx.io.core.readAvailable
 import kotlinx.io.core.use
 import kotlinx.serialization.InternalSerializationApi
 import net.mamoe.mirai.qqandroid.QQAndroidBot
 import net.mamoe.mirai.qqandroid.network.QQAndroidClient
 import net.mamoe.mirai.qqandroid.network.protocol.data.proto.CSDataHighwayHead
-import net.mamoe.mirai.qqandroid.utils.*
+import net.mamoe.mirai.qqandroid.utils.PlatformSocket
+import net.mamoe.mirai.qqandroid.utils.SocketException
+import net.mamoe.mirai.qqandroid.utils.addSuppressedMirai
 import net.mamoe.mirai.qqandroid.utils.io.serialization.readProtoBuf
 import net.mamoe.mirai.qqandroid.utils.io.withUse
-import net.mamoe.mirai.utils.*
+import net.mamoe.mirai.qqandroid.utils.toIpV4AddressString
+import net.mamoe.mirai.utils.ExternalImage
+import net.mamoe.mirai.utils.MiraiExperimentalAPI
+import net.mamoe.mirai.utils.MiraiInternalAPI
+import net.mamoe.mirai.utils.verbose
 import kotlin.coroutines.EmptyCoroutineContext
 import kotlin.math.roundToInt
 import kotlin.time.ExperimentalTime
@@ -75,26 +77,8 @@ internal suspend fun HttpClient.postImage(
 
         @OptIn(MiraiExperimentalAPI::class)
         override suspend fun writeTo(channel: ByteWriteChannel) {
-            ByteArrayPool.useInstance { buffer: ByteArray ->
-                when (imageInput) {
-                    is Input -> {
-                        var size: Int
-                        while (imageInput.readAvailable(buffer).also { size = it } > 0) {
-                            channel.writeFully(buffer, 0, size)
-                            channel.flush()
-                        }
-                    }
-                    is ByteReadChannel -> imageInput.copyAndClose(channel)
-                    is InputStream -> {
-                        var size: Int
-                        while (imageInput.read(buffer).also { size = it } > 0) {
-                            channel.writeFully(buffer, 0, size)
-                            channel.flush()
-                        }
-                    }
-                    else -> error("unsupported imageInput: ${imageInput::class.simpleName}")
-                }
-            }
+            imageInput.writeTo(channel)
+
         }
     }
 } == HttpStatusCode.OK
@@ -109,26 +93,26 @@ internal object HighwayHelper {
         image: ExternalImage.ReusableInput,
         kind: String,
         commandId: Int
-    ) = uploadImageToServers(bot, servers, uKey, image.md5, image.input(), image.size, kind, commandId)
+    ) = uploadImageToServers(bot, servers, uKey, image.md5, image, kind, commandId)
 
+    @Suppress("INVISIBLE_REFERENCE", "INVISIBLE_MEMBER")
     @OptIn(ExperimentalTime::class)
     suspend fun uploadImageToServers(
         bot: QQAndroidBot,
         servers: List<Pair<Int, Int>>,
         uKey: ByteArray,
         md5: ByteArray,
-        input: Any,
-        inputSize: Long,
+        input: ExternalImage.ReusableInput,
         kind: String,
         commandId: Int
     ) = servers.retryWithServers(
-        (inputSize * 1000 / 1024 / 10).coerceAtLeast(5000),
+        (input.size * 1000 / 1024 / 10).coerceAtLeast(5000),
         onFail = {
             throw IllegalStateException("cannot upload $kind, failed on all servers.", it)
         }
     ) { ip, port ->
         bot.network.logger.verbose {
-            "[Highway] Uploading $kind to ${ip}:$port, size=${inputSize.sizeToString()}"
+            "[Highway] Uploading $kind to ${ip}:$port, size=${input.size.sizeToString()}"
         }
 
         val time = measureTime {
@@ -137,7 +121,6 @@ internal object HighwayHelper {
                 serverIp = ip,
                 serverPort = port,
                 imageInput = input,
-                inputSize = inputSize,
                 fileMd5 = md5,
                 ticket = uKey,
                 commandId = commandId
@@ -145,22 +128,21 @@ internal object HighwayHelper {
         }
 
         bot.network.logger.verbose {
-            "[Highway] Uploading $kind: succeed at ${(inputSize.toDouble() / 1024 / time.inSeconds).roundToInt()} KiB/s"
+            "[Highway] Uploading $kind: succeed at ${(input.size.toDouble() / 1024 / time.inSeconds).roundToInt()} KiB/s"
         }
     }
 
+    @Suppress("INVISIBLE_REFERENCE", "INVISIBLE_MEMBER")
     @OptIn(InternalCoroutinesApi::class)
     internal suspend fun uploadImage(
         client: QQAndroidClient,
         serverIp: String,
         serverPort: Int,
         ticket: ByteArray,
-        imageInput: Any,
-        inputSize: Long,
+        imageInput: ExternalImage.ReusableInput,
         fileMd5: ByteArray,
         commandId: Int  // group=2, friend=1
     ) {
-        require(imageInput is Input || imageInput is InputStream || imageInput is ByteReadChannel) { "unsupported imageInput: ${imageInput::class.simpleName}" }
         require(fileMd5.size == 16) { "bad md5. Required size=16, got ${fileMd5.size}" }
         //  require(ticket.size == 128) { "bad uKey. Required size=128, got ${ticket.size}" }
         // require(commandId == 2 || commandId == 1) { "bad commandId. Must be 1 or 2" }
@@ -181,18 +163,19 @@ internal object HighwayHelper {
                 commandId = commandId,
                 ticket = ticket,
                 data = imageInput,
-                dataSize = inputSize,
                 fileMd5 = fileMd5
-            ).collect {
-                socket.send(it)
-                //0A 3C 08 01 12 0A 31 39 39 34 37 30 31 30 32 31 1A 0C 50 69 63 55 70 2E 44 61 74 61 55 70 20 E9 A7 05 28 00 30 BD DB 8B 80 02 38 80 20 40 02 4A 0A 38 2E 32 2E 30 2E 31 32 39 36 50 84 10 12 3D 08 00 10 FD 08 18 00 20 FD 08 28 C6 01 38 00 42 10 D4 1D 8C D9 8F 00 B2 04 E9 80 09 98 EC F8 42 7E 4A 10 D4 1D 8C D9 8F 00 B2 04 E9 80 09 98 EC F8 42 7E 50 89 92 A2 FB 06 58 00 60 00 18 53 20 01 28 00 30 04 3A 00 40 E6 B7 F7 D9 80 2E 48 00 50 00
-
-                socket.read().withUse {
-                    discardExact(1)
-                    val headLength = readInt()
-                    discardExact(4)
-                    val proto = readProtoBuf(CSDataHighwayHead.RspDataHighwayHead.serializer(), length = headLength)
-                    check(proto.errorCode == 0) { "highway transfer failed, error ${proto.errorCode}" }
+            ).withUse {
+                flow.collect {
+                    socket.send(it)
+                    //0A 3C 08 01 12 0A 31 39 39 34 37 30 31 30 32 31 1A 0C 50 69 63 55 70 2E 44 61 74 61 55 70 20 E9 A7 05 28 00 30 BD DB 8B 80 02 38 80 20 40 02 4A 0A 38 2E 32 2E 30 2E 31 32 39 36 50 84 10 12 3D 08 00 10 FD 08 18 00 20 FD 08 28 C6 01 38 00 42 10 D4 1D 8C D9 8F 00 B2 04 E9 80 09 98 EC F8 42 7E 4A 10 D4 1D 8C D9 8F 00 B2 04 E9 80 09 98 EC F8 42 7E 50 89 92 A2 FB 06 58 00 60 00 18 53 20 01 28 00 30 04 3A 00 40 E6 B7 F7 D9 80 2E 48 00 50 00
+
+                    socket.read().withUse {
+                        discardExact(1)
+                        val headLength = readInt()
+                        discardExact(4)
+                        val proto = readProtoBuf(CSDataHighwayHead.RspDataHighwayHead.serializer(), length = headLength)
+                        check(proto.errorCode == 0) { "highway transfer failed, error ${proto.errorCode}" }
+                    }
                 }
             }
         }

mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/network/highway/highway.kt

@@ -11,12 +11,7 @@
 
 package net.mamoe.mirai.qqandroid.network.highway
 
-import kotlinx.coroutines.flow.Flow
-import kotlinx.coroutines.flow.map
-import kotlinx.coroutines.io.ByteReadChannel
-import kotlinx.io.InputStream
 import kotlinx.io.core.ByteReadPacket
-import kotlinx.io.core.Input
 import kotlinx.io.core.buildPacket
 import kotlinx.io.core.writeFully
 import kotlinx.serialization.InternalSerializationApi
@@ -25,9 +20,12 @@ import net.mamoe.mirai.qqandroid.network.protocol.data.proto.CSDataHighwayHead
 import net.mamoe.mirai.qqandroid.network.protocol.packet.EMPTY_BYTE_ARRAY
 import net.mamoe.mirai.qqandroid.utils.ByteArrayPool
 import net.mamoe.mirai.qqandroid.utils.MiraiPlatformUtils
-import net.mamoe.mirai.qqandroid.utils.io.chunkedFlow
 import net.mamoe.mirai.qqandroid.utils.io.serialization.toByteArray
+import net.mamoe.mirai.utils.ExternalImage
 import net.mamoe.mirai.utils.MiraiInternalAPI
+import net.mamoe.mirai.utils.internal.ChunkedFlowSession
+import net.mamoe.mirai.utils.internal.ChunkedInput
+import net.mamoe.mirai.utils.internal.map
 
 @OptIn(MiraiInternalAPI::class, InternalSerializationApi::class)
 internal fun createImageDataPacketSequence(
@@ -39,27 +37,17 @@ internal fun createImageDataPacketSequence(
     commandId: Int,
     localId: Int = 2052,
     ticket: ByteArray,
-
-    data: Any,
-    dataSize: Long,
+    data: ExternalImage.ReusableInput,
     fileMd5: ByteArray,
     sizePerPacket: Int = ByteArrayPool.BUFFER_SIZE
-): Flow<ByteReadPacket> {
+): ChunkedFlowSession<ByteReadPacket> {
     ByteArrayPool.checkBufferSize(sizePerPacket)
-    require(data is Input || data is InputStream || data is ByteReadChannel) { "unsupported data: ${data::class.simpleName}" }
     //   require(ticket.size == 128) { "bad uKey. Required size=128, got ${ticket.size}" }
-    require(data !is ByteReadPacket) { "bad input. given dataSize=$dataSize, but actual readRemaining=${(data as ByteReadPacket).remaining}" }
 
-    val flow = when (data) {
-        is ByteReadPacket -> data.chunkedFlow(sizePerPacket)
-        is Input -> data.chunkedFlow(sizePerPacket)
-        is ByteReadChannel -> data.chunkedFlow(sizePerPacket)
-        is InputStream -> data.chunkedFlow(sizePerPacket)
-        else -> error("unreachable code")
-    }
+    val session: ChunkedFlowSession<ChunkedInput> = data.chunkedFlow(sizePerPacket)
 
     var offset = 0L
-    return flow.map { chunkedInput ->
+    return session.map { chunkedInput ->
         buildPacket {
             val head = CSDataHighwayHead.ReqDataHighwayHead(
                 msgBasehead = CSDataHighwayHead.DataHighwayHead(
@@ -82,7 +70,7 @@ internal fun createImageDataPacketSequence(
                     //   cacheAddr = 812157193,
                     datalength = chunkedInput.bufferSize,
                     dataoffset = offset,
-                    filesize = dataSize,
+                    filesize = data.size,
                     serviceticket = ticket,
                     md5 = MiraiPlatformUtils.md5(chunkedInput.buffer, 0, chunkedInput.bufferSize),
                     fileMd5 = fileMd5,

mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/network/protocol/packet/PacketFactory.kt

@@ -197,6 +197,7 @@ internal object KnownPacketFactories {
 
             readString(readInt() - 4)// uinAccount
 
+            @Suppress("INVISIBLE_MEMBER", "INVISIBLE_REFERENCE")
             ByteArrayPool.useInstance(this.remaining.toInt()) { data ->
                 val size = this.readAvailable(data)
 
@@ -385,6 +386,7 @@ internal object KnownPacketFactories {
             }
             0 -> {
                 val data = if (bot.client.loginState == 0) {
+                    @Suppress("INVISIBLE_MEMBER", "INVISIBLE_REFERENCE")
                     ByteArrayPool.useInstance(this.remaining.toInt()) { byteArrayBuffer ->
                         val size = (this.remaining - 1).toInt()
                         this.readFully(byteArrayBuffer, 0, size)

mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/network/protocol/packet/login/ConfigPushSvc.kt

@@ -70,6 +70,7 @@ internal class ConfigPushSvc {
 
 
         override suspend fun ByteReadPacket.decode(bot: QQAndroidBot, sequenceId: Int): PushReqResponse? {
+            @Suppress("INVISIBLE_MEMBER", "INVISIBLE_REFERENCE")
             ByteArrayPool.useInstance(this.remaining.toInt()) { buffer ->
                 val length = this.readAvailable(buffer)
 

mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/utils/ByteArrayPool.kt

@@ -1,41 +1,9 @@
 package net.mamoe.mirai.qqandroid.utils
 
-import kotlinx.io.pool.DefaultPool
 import kotlinx.io.pool.ObjectPool
 
 /**
  * 缓存 [ByteArray] 实例的 [ObjectPool]
  */
-internal object ByteArrayPool : DefaultPool<ByteArray>(256) {
-    /**
-     * 每一个 [ByteArray] 的大小
-     */
-    const val BUFFER_SIZE: Int = 8192 * 8
-
-    override fun produceInstance(): ByteArray = ByteArray(BUFFER_SIZE)
-
-    override fun clearInstance(instance: ByteArray): ByteArray = instance
-
-    fun checkBufferSize(size: Int) {
-        require(size <= BUFFER_SIZE) { "sizePerPacket is too large. Maximum buffer size=$BUFFER_SIZE" }
-    }
-
-    fun checkBufferSize(size: Long) {
-        require(size <= BUFFER_SIZE) { "sizePerPacket is too large. Maximum buffer size=$BUFFER_SIZE" }
-    }
-
-    /**
-     * 请求一个大小至少为 [requestedSize] 的 [ByteArray] 实例.
-     */ // 不要写为扩展函数. 它需要优先于 kotlinx.io 的扩展函数 resolve
-    inline fun <R> useInstance(requestedSize: Int = 0, block: (ByteArray) -> R): R {
-        if (requestedSize > BUFFER_SIZE) {
-            return ByteArray(requestedSize).run(block)
-        }
-        val instance = borrow()
-        try {
-            return block(instance)
-        } finally {
-            recycle(instance)
-        }
-    }
-}
+@Suppress("INVISIBLE_MEMBER", "INVISIBLE_REFERENCE")
+internal typealias ByteArrayPool = net.mamoe.mirai.utils.internal.ByteArrayPool

mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/utils/io/input.kt

@@ -27,6 +27,7 @@ import kotlin.jvm.JvmMultifileClass
 import kotlin.jvm.JvmName
 import kotlin.jvm.JvmSynthetic
 
+@Suppress("INVISIBLE_MEMBER", "INVISIBLE_REFERENCE")
 internal inline fun <R> ByteReadPacket.useBytes(
     n: Int = remaining.toInt(),//not that safe but adequate
     block: (data: ByteArray, length: Int) -> R

mirai-core/src/commonMain/kotlin/net.mamoe.mirai/utils/ExternalImage.kt

@@ -11,18 +11,15 @@
 
 package net.mamoe.mirai.utils
 
-import kotlinx.coroutines.io.ByteReadChannel
-import kotlinx.io.InputStream
-import kotlinx.io.core.ByteReadPacket
-import kotlinx.io.core.Input
-import kotlinx.serialization.InternalSerializationApi
+import io.ktor.utils.io.ByteWriteChannel
 import net.mamoe.mirai.contact.Contact
 import net.mamoe.mirai.contact.Group
 import net.mamoe.mirai.contact.User
 import net.mamoe.mirai.message.MessageReceipt
 import net.mamoe.mirai.message.data.Image
 import net.mamoe.mirai.message.data.sendTo
-import net.mamoe.mirai.utils.internal.asReusableInput
+import net.mamoe.mirai.utils.internal.ChunkedFlowSession
+import net.mamoe.mirai.utils.internal.ChunkedInput
 import kotlin.jvm.JvmField
 import kotlin.jvm.JvmSynthetic
 
@@ -36,43 +33,20 @@ import kotlin.jvm.JvmSynthetic
  */
 @OptIn(MiraiInternalAPI::class)
 class ExternalImage internal constructor(
-    val md5: ByteArray,
     @JvmField
     internal val input: ReusableInput // Input from kotlinx.io, InputStream from kotlinx.io MPP, ByteReadChannel from ktor
 ) {
+    val md5: ByteArray get() = this.input.md5
+
     @SinceMirai("1.0.0")
     internal interface ReusableInput {
         val md5: ByteArray
         val size: Long
 
-        /**
-         * Create a input for once usage
-         */
-        fun input(): Input
+        fun chunkedFlow(sizePerPacket: Int): ChunkedFlowSession<ChunkedInput>
+        suspend fun writeTo(out: ByteWriteChannel): Long
     }
 
-
-    constructor(
-        md5: ByteArray,
-        input: ByteReadChannel
-    ) : this(md5, input.asReusableInput())
-
-    constructor(
-        md5: ByteArray,
-        input: Input
-    ) : this(md5, input.asReusableInput())
-
-    constructor(
-        md5: ByteArray,
-        input: ByteReadPacket
-    ) : this(md5, input.asReusableInput())
-
-    @OptIn(InternalSerializationApi::class)
-    constructor(
-        md5: ByteArray,
-        input: InputStream
-    ) : this(md5, input.asReusableInput())
-
     init {
         require(input.size < 30L * 1024 * 1024) { "Image file is too big. Maximum is 30 MiB, but recommended to be 20 MiB" }
     }

mirai-core/src/commonMain/kotlin/net.mamoe.mirai/utils/internal/asReusableInput.common.kt

@@ -9,15 +9,9 @@
 
 package net.mamoe.mirai.utils.internal
 
-import kotlinx.coroutines.io.ByteReadChannel
-import kotlinx.io.InputStream
-import kotlinx.io.core.Input
-import kotlinx.serialization.InternalSerializationApi
 import net.mamoe.mirai.utils.ExternalImage
 
 
-internal expect fun ByteReadChannel.asReusableInput(): ExternalImage.ReusableInput
-internal expect fun Input.asReusableInput(): ExternalImage.ReusableInput
+internal expect fun ByteArray.asReusableInput(): ExternalImage.ReusableInput
 
-@OptIn(InternalSerializationApi::class)
-internal expect fun InputStream.asReusableInput(): ExternalImage.ReusableInput
+internal fun asReusableInput0(input: ByteArray): ExternalImage.ReusableInput = input.asReusableInput()

mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/utils/io/chunked.kt → mirai-core/src/commonMain/kotlin/net.mamoe.mirai/utils/internal/chunked.kt

@@ -7,20 +7,33 @@
  * https://github.com/mamoe/mirai/blob/master/LICENSE
  */
 
-package net.mamoe.mirai.qqandroid.utils.io
+package net.mamoe.mirai.utils.internal
 
 import kotlinx.coroutines.ExperimentalCoroutinesApi
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.flow
 import kotlinx.coroutines.flow.flowOf
+import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.io.ByteReadChannel
 import kotlinx.io.InputStream
 import kotlinx.io.core.ByteReadPacket
+import kotlinx.io.core.Closeable
 import kotlinx.io.core.Input
-import kotlinx.io.pool.useInstance
-import net.mamoe.mirai.utils.MiraiInternalAPI
 import kotlinx.serialization.InternalSerializationApi
-import net.mamoe.mirai.qqandroid.utils.ByteArrayPool
+import kotlin.jvm.JvmField
+
+
+internal interface ChunkedFlowSession<T> : Closeable {
+    val flow: Flow<T>
+    override fun close()
+}
+
+internal inline fun <T, R> ChunkedFlowSession<T>.map(crossinline mapper: suspend ChunkedFlowSession<T>.(T) -> R): ChunkedFlowSession<R> {
+    return object : ChunkedFlowSession<R> {
+        override val flow: Flow<R> = [email protected] { [email protected](it) }
+        override fun close() = [email protected]()
+    }
+}
 
 
 /**
@@ -34,13 +47,13 @@ internal class ChunkedInput(
      *
      * **注意**: 不要将他带出 [Flow.collect] 作用域, 否则将造成内存泄露
      */
-    val buffer: ByteArray,
-    internal var size: Int
+    @JvmField val buffer: ByteArray,
+    @JvmField internal var size: Int
 ) {
     /**
      * [buffer] 的有效大小
      */
-    val bufferSize: Int get() = size
+    inline val bufferSize: Int get() = size
 }
 
 /**
@@ -51,7 +64,6 @@ internal class ChunkedInput(
  *
  * 若 [ByteReadPacket.remaining] 小于 [sizePerPacket], 将会返回唯一元素 [this] 的 [Sequence]
  */
-@OptIn(MiraiInternalAPI::class)
 internal fun ByteReadPacket.chunkedFlow(sizePerPacket: Int): Flow<ChunkedInput> {
     ByteArrayPool.checkBufferSize(sizePerPacket)
     if (this.remaining <= sizePerPacket.toLong()) {
@@ -81,7 +93,6 @@ internal fun ByteReadPacket.chunkedFlow(sizePerPacket: Int): Flow<ChunkedInput>
  * 对于一个 1000 长度的 [ByteReadChannel] 和参数 [sizePerPacket] = 300, 将会产生含四个元素的 [Sequence],
  * 其长度分别为: 300, 300, 300, 100.
  */
-@OptIn(MiraiInternalAPI::class)
 internal fun ByteReadChannel.chunkedFlow(sizePerPacket: Int): Flow<ChunkedInput> {
     ByteArrayPool.checkBufferSize(sizePerPacket)
     if (this.isClosedForRead) {
@@ -105,7 +116,7 @@ internal fun ByteReadChannel.chunkedFlow(sizePerPacket: Int): Flow<ChunkedInput>
  * 对于一个 1000 长度的 [Input] 和参数 [sizePerPacket] = 300, 将会产生含四个元素的 [Sequence],
  * 其长度分别为: 300, 300, 300, 100.
  */
-@OptIn(MiraiInternalAPI::class, ExperimentalCoroutinesApi::class)
+@OptIn(ExperimentalCoroutinesApi::class)
 internal fun Input.chunkedFlow(sizePerPacket: Int): Flow<ChunkedInput> {
     ByteArrayPool.checkBufferSize(sizePerPacket)
 
@@ -132,9 +143,7 @@ internal fun Input.chunkedFlow(sizePerPacket: Int): Flow<ChunkedInput> {
  *
  * 若 [ByteReadPacket.remaining] 小于 [sizePerPacket], 将会返回唯一元素 [this] 的 [Sequence]
  */
-@OptIn(
-    MiraiInternalAPI::class, ExperimentalCoroutinesApi::class, InternalSerializationApi::class
-)
+@OptIn(ExperimentalCoroutinesApi::class, InternalSerializationApi::class)
 internal fun InputStream.chunkedFlow(sizePerPacket: Int): Flow<ChunkedInput> {
     ByteArrayPool.checkBufferSize(sizePerPacket)
 

mirai-core/src/commonMain/kotlin/net.mamoe.mirai/utils/internal/md5.common.kt

@@ -38,11 +38,11 @@ internal inline fun InputStream.readInSequence(block: (ByteArray, len: Int) -> U
 /**
  * 缓存 [ByteArray] 实例的 [ObjectPool]
  */
-internal object ByteArrayPool : DefaultPool<ByteArray>(32) {
+internal object ByteArrayPool : DefaultPool<ByteArray>(256) {
     /**
      * 每一个 [ByteArray] 的大小
      */
-    const val BUFFER_SIZE: Int = 8192
+    const val BUFFER_SIZE: Int = 8192 * 8
 
     override fun produceInstance(): ByteArray = ByteArray(BUFFER_SIZE)
 

mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/utils/ExternalImageJvm.kt

@@ -18,6 +18,7 @@ import kotlinx.io.core.Input
 import kotlinx.io.core.copyTo
 import kotlinx.io.errors.IOException
 import kotlinx.io.streams.asOutput
+import net.mamoe.mirai.utils.internal.asReusableInput
 import net.mamoe.mirai.utils.internal.md5
 import java.awt.image.BufferedImage
 import java.io.File
@@ -63,7 +64,7 @@ fun BufferedImage.toExternalImage(formatName: String = "png"): ExternalImage {
     }
 
     @Suppress("DEPRECATION_ERROR")
-    return ExternalImage(digest.digest(), file.inputStream())
+    return ExternalImage(file.asReusableInput())
 }
 
 suspend inline fun BufferedImage.suspendToExternalImage(): ExternalImage = withContext(IO) { toExternalImage() }
@@ -76,8 +77,7 @@ suspend inline fun BufferedImage.suspendToExternalImage(): ExternalImage = withC
 fun File.toExternalImage(): ExternalImage {
     @Suppress("DEPRECATION_ERROR")
     return ExternalImage(
-        md5 = this.inputStream().md5(), // dont change
-        input = this.inputStream()
+        input = this.asReusableInput()
     )
 }
 

mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/utils/internal/asReusableInput.jvm.kt

@@ -1,18 +1,70 @@
 package net.mamoe.mirai.utils.internal
 
-import kotlinx.coroutines.io.ByteReadChannel
-import kotlinx.io.core.Input
+import io.ktor.utils.io.ByteWriteChannel
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.withContext
+import net.mamoe.mirai.message.data.toLongUnsigned
 import net.mamoe.mirai.utils.ExternalImage
+import java.io.File
 import java.io.InputStream
 
-internal actual fun ByteReadChannel.asReusableInput(): ExternalImage.ReusableInput {
-    TODO("Not yet implemented")
+internal actual fun ByteArray.asReusableInput(): ExternalImage.ReusableInput {
+    return object : ExternalImage.ReusableInput {
+        override val md5: ByteArray = md5()
+        override val size: Long get() = [email protected]()
+
+        override fun chunkedFlow(sizePerPacket: Int): ChunkedFlowSession<ChunkedInput> {
+            return object : ChunkedFlowSession<ChunkedInput> {
+                override val flow: Flow<ChunkedInput> = inputStream().chunkedFlow(sizePerPacket)
+
+                override fun close() {
+                    // nothing to do
+                }
+            }
+        }
+
+        override suspend fun writeTo(out: ByteWriteChannel): Long {
+            out.writeFully(this@asReusableInput, 0, [email protected])
+            out.flush()
+            return [email protected]()
+        }
+    }
 }
 
-internal actual fun Input.asReusableInput(): ExternalImage.ReusableInput {
-    TODO("Not yet implemented")
+internal fun File.asReusableInput(): ExternalImage.ReusableInput {
+    return object : ExternalImage.ReusableInput {
+        override val md5: ByteArray = inputStream().use { it.md5() }
+        override val size: Long get() = length()
+
+        override fun chunkedFlow(sizePerPacket: Int): ChunkedFlowSession<ChunkedInput> {
+            val stream = inputStream()
+            return object : ChunkedFlowSession<ChunkedInput> {
+                override val flow: Flow<ChunkedInput> = stream.chunkedFlow(sizePerPacket)
+                override fun close() = stream.close()
+            }
+        }
+
+        override suspend fun writeTo(out: ByteWriteChannel): Long {
+            return inputStream().use { it.copyTo(out) }
+        }
+    }
 }
 
-internal actual fun InputStream.asReusableInput(): ExternalImage.ReusableInput {
-    TODO("Not yet implemented")
+
+private suspend fun InputStream.copyTo(out: ByteWriteChannel): Long = withContext(Dispatchers.IO) {
+    var bytesCopied: Long = 0
+
+    ByteArrayPool.useInstance { buffer ->
+        var bytes = read(buffer)
+        while (bytes >= 0) {
+            out.writeFully(buffer, 0, bytes)
+            bytesCopied += bytes
+            bytes = read(buffer)
+        }
+    }
+
+    out.flush()
+
+    return@withContext bytesCopied
 }