WasmRunner.js

import EmscrWasmRunnable from "../runnables/EmscriptenRunnable"
import WasmerRunnable from "../runnables/WasmerRunnable"

/* executes wasm on the main thread. asks for stdin by using prompts.
this class will be extented by WasmWorker to run on worker thread. */

class WasmRunner {
  outputBuffer

  constructor() {
    this.outputBuffer = ""
  }

  runCommand(
    programName,
    wasmModule,
    wasmModuleType,
    argv,
    stdinProxy,
    stdoutProxy,
    stderrProxy,
    files,
    onFinish,
    onError,
    onSuccess,
    stdinPreset,
    emscrJsRuntime
  ) {
    // initialize default callbacks
    if (typeof onFinish != "function") onFinish = () => {}
    if (typeof onError != "function")
      onError = (e) => {
        console.error(e)
      }
    if (typeof onSuccess != "function") onSuccess = () => {}

    // store outputs of stdout in buffer (for stdin prompts)
    const bufferOutputs = (value) => {
      this.outputBuffer +=
        typeof value == "number" ? String.fromCharCode(value) : value
    }
    const stdoutHandler = (value) => {
      bufferOutputs(value)
      return stdoutProxy(value)
    }
    const stderrHandler = (value) => {
      bufferOutputs(value)
      return stderrProxy(value)
    }

    if (wasmModuleType == "emscripten") {
      // instantiate new emscr runnable
      console.log("wasm runner creates new emscr runnable")
      let emscrWasmExe = new EmscrWasmRunnable(
        programName,
        wasmModule,
        emscrJsRuntime
      )

      // pipe stdin calls through stdin handler (which pauses thread)
      const stdinHandler = (tty) =>
        this._onEmscrStdinCall(tty, stdinProxy, stdoutHandler, stderrHandler)

      // run command on it
      emscrWasmExe.run(
        argv,
        stdinHandler,
        stdoutHandler,
        stderrHandler,
        files,
        onFinish,
        onError,
        onSuccess,
        stdinPreset
      )
    } else if (wasmModuleType == "wasmer") {
      // instantiate new wasmer runnable
      console.log("wasm runner creates new wasmer runnable")
      let wasmerExe = new WasmerRunnable(programName, wasmModule)

      // pipe stdin calls through stdin handler (which pauses thread)
      const stdinHandler = (stdinBuffer) =>
        this._onWasmerStdinCall(
          stdinBuffer,
          stdinProxy,
          stdoutHandler,
          stderrHandler
        )

      // run command on it
      wasmerExe.run(
        argv,
        stdinHandler,
        stdoutHandler,
        stderrHandler,
        files,
        onFinish,
        onError,
        onSuccess,
        stdinPreset
      )
    } else
      throw new Error(
        "Unknown wasm module type (can only handle emscripten or wasmer)"
      )
  }

  runCommandHeadless(
    programName,
    wasmModule,
    wasmModuleType,
    argv,
    files,
    onFinish,
    onError,
    onSuccess,
    stdinPreset,
    emscrJsRuntime
  ) {
    // initialize default callbacks
    if (typeof onFinish != "function") onFinish = () => {}
    if (typeof onError != "function")
      onError = (e) => {
        console.error(e)
      }
    if (typeof onSuccess != "function") onSuccess = () => {}

    if (wasmModuleType == "emscripten") {
      // instantiate new emscr runnable
      console.log("wasm runner creates new emscr runnable")
      let emscrWasmExe = new EmscrWasmRunnable(
        programName,
        wasmModule,
        emscrJsRuntime
      )

      // run command on it
      emscrWasmExe.runHeadless(
        argv,
        files,
        onFinish,
        onError,
        onSuccess,
        stdinPreset
      )
    } else if (wasmModuleType == "wasmer") {
      // instantiate new wasmer runnable
      let wasmerExe = new WasmerRunnable(programName, wasmModule)

      // run command on it
      wasmerExe.runHeadless(
        argv,
        files,
        onFinish,
        onError,
        onSuccess,
        stdinPreset
      )
    } else
      throw new Error(
        "Unknown wasm module type (can only handle emscripten or wasmer)"
      )
  }

  // handles stdin calls from emscr (tty is passed by emscr js runtime)
  _onEmscrStdinCall(tty, stdinProxy, stdoutProxy, stderrProxy) {
    if (tty.input.length == 0) {
      // use last line from output buffer as prompt caption
      const promptCaption = this.outputBuffer.split(/\r?\n/g).pop()

      // get input from user via prompt
      const input = window.prompt(promptCaption)

      // if aborted -> end
      if (input == null) return null

      // print input to terminal
      stdoutProxy(input)
      if (!promptCaption) stdoutProxy("\r\n")

      // copy input value to tty input
      tty.input = (input + "\n").split("").map((char) => char.charCodeAt(0))
      tty.input.push(null) // marks end
    }

    // deliver input
    return tty.input.shift()
  }

  // handles stdin calls from wasmer
  _onWasmerStdinCall(stdinBuffer, stdinProxy, stdoutProxy, stderrProxy) {
    // use last line from output buffer as prompt caption
    const promptCaption = this.outputBuffer.split(/\r?\n/g).pop()

    // get input from user via prompt
    const input = window.prompt(promptCaption)

    // if aborted -> end
    if (input == null) return 0

    // print input to terminal
    stdoutProxy(input)
    if (!promptCaption) stdoutProxy("\r\n")

    // copy input value to stdinBuffer
    Array.from(input + "\n").forEach(
      (char, i) => (stdinBuffer[i] = char.charCodeAt(0))
    )

    // return how much to read
    return input.length + 1
  }
}

export default WasmRunner
export const MODULE_ID = __webpack_module__.id