Improve pages loading #256

app/src/main/java/org/koitharu/kotatsu/utils/ext/IO.kt

@@ -0,0 +1,27 @@
+package org.koitharu.kotatsu.utils.ext
+
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.currentCoroutineContext
+import kotlinx.coroutines.ensureActive
+import kotlinx.coroutines.withContext
+import java.io.InputStream
+import java.io.OutputStream
+
+suspend fun InputStream.copyToSuspending(
+	out: OutputStream,
+	bufferSize: Int = DEFAULT_BUFFER_SIZE
+): Long = withContext(Dispatchers.IO) {
+	val job = currentCoroutineContext()[Job]
+	var bytesCopied: Long = 0
+	val buffer = ByteArray(bufferSize)
+	var bytes = read(buffer)
+	while (bytes >= 0) {
+		out.write(buffer, 0, bytes)
+		bytesCopied += bytes
+		job?.ensureActive()
+		bytes = read(buffer)
+		job?.ensureActive()
+	}
+	bytesCopied
+}