KTOR-6147 Darwin: App hangs when streaming request without connection (…

…#3720)

(cherry picked from commit c75fce9)

ktor-client/ktor-client-darwin/darwin/src/io/ktor/client/engine/darwin/DarwinUtils.kt

@@ -9,13 +9,10 @@ import io.ktor.client.engine.*
 import io.ktor.http.content.*
 import io.ktor.util.*
 import io.ktor.utils.io.*
-import io.ktor.utils.io.core.*
 import io.ktor.utils.io.errors.*
 import kotlinx.cinterop.*
-import kotlinx.cinterop.ByteVar
 import kotlinx.coroutines.*
 import platform.Foundation.*
-import platform.darwin.*
 import platform.posix.*
 
 @OptIn(DelicateCoroutinesApi::class, UnsafeNumber::class, InternalAPI::class)
@@ -53,10 +50,19 @@ internal suspend fun OutgoingContent.toDataOrStream(): Any? {
  var offset = 0
  val read = channel.readAvailable(buffer, 0, 4096)
  while (offset < read) {
+ while (!outputStream.hasSpaceAvailable) {
+ yield()
+ }
  @Suppress("UNCHECKED_CAST")
  val written = outputStream
- .write(buffer.plus(offset) as CPointer<UByteVar>, (read - offset).convert()).convert<Int>()
+ .write(buffer.plus(offset) as CPointer<UByteVar>, (read - offset).convert())
+ .convert<Int>()
  offset += written
+ if (written < 0) {
+ throw outputStream.streamError?.let { DarwinHttpRequestException(it) }
+ ?: inputStream.streamError?.let { DarwinHttpRequestException(it) }
+ ?: IOException("Failed to write to the network")
+ }
  }
  }
  }