git ssb

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module.exports = class VM {
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  /**
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   * The interface API is the api the exposed to interfaces. All queries about
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   * the enviroment and call to the kernel go through this API
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   */
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  constructor (code) {
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    this._module = WebAssembly.Module(code)
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  }
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  /**
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   * Runs the core VM with a given environment and imports
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   */
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  run (environment, imports) {
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    this._environment = environment
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    // TODO, delete the instance once done.
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    const instance = this._instance = WebAssembly.Instance(this._module, imports)
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    if (instance.exports.main) {
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      instance.exports.main()
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    }
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    return this.onDone()
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  }
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  /**
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   * returns a promise that resolves when the wasm instance is done running
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   */
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  async onDone () {
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    let prevOps
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    while (prevOps !== this._opsQueue) {
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      prevOps = this._opsQueue
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      await this._opsQueue
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    }
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  }
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  /**
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   * addes an aync operation to the operations queue
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   */
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  pushOpsQueue (promise, callbackIndex, intefaceCallback) {
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    this._opsQueue = Promise.all([this._opsQueue, promise]).then(values => {
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      const result = intefaceCallback(values.pop())
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      this._instance.exports[callbackIndex.toString()](result)
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    })
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  }
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  sendMessage (message) {
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  }
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  get environment () {
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    return this._environment
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  }
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  get memory () {
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    return this._instance.exports.memory.buffer
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  }
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}
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