et len = 0;
  for (
    let ptr = cast(input, uint8_t.ptr);
    ptr.contents;
    ptr = ptr.increment()
  ) {
    len++;
  }

  let aryPtr = cast(input, uint8_t.array(len).ptr);
  return new Uint8Array(aryPtr.contents);
}

var SubprocessUnix = {
  Process,

  call(options) {
    return Process.create(options);
  },

  *getEnvironment() {
    let environ;
    if (Services.appinfo.OS === "Darwin") {
      environ = libc._NSGetEnviron().contents;
    } else {
      environ = libc.environ;
    }

    const EQUAL = "=".charCodeAt(0);
    let decoder = new TextDecoder("utf-8", { fatal: true });

    function decode(array) {
      try {
        return decoder.decode(array);
      } catch (e) {
        return array;
      }
    }

    for (
      let envp = environ;
      !envp.isNull() && !envp.contents.isNull();
      envp = envp.increment()
    ) {
      let buf = ptrToUint8Array(envp.contents);

      for (let i = 0; i < buf.length; i++) {
        if (buf[i] == EQUAL) {
          yield [decode(buf.subarray(0, i)), decode(buf.subarray(i + 1))];
          break;
        }
      }
    }
  },

  isExecutableFile: async function isExecutable(path) {
    if (!PathUtils.isAbsolute(path)) {
      return false;
    }

    try {
      let info = await IOUtils.stat(path);

      // FIXME: We really want access(path, X_OK) here, but IOUtils does not
      // support it.
      return info.type !== "directory" && info.permissions & 0o111;
    } catch (e) {
      return false;
    }
  },

  /**
   * Searches for the given executable file in the system executable
   * file paths as specified by the PATH environment variable.
   *
   * On Windows, if the unadorned filename cannot be found, the
   * extensions in the semicolon-separated list in the PATHEXT
   * environment variable are successively appended to the original
   * name and searched for in turn.
   *
   * @param {string} bin
   *        The name of the executable to find.
   * @param {object} environment
   *        An object containing a key for each environment variable to be used
   *        in the search.
   * @returns {Promise<string>}
   */
  async pathSearch(bin, environment) {
    if (PathUtils.isAbsolute(bin)) {
      if (await this.isExecutableFile(bin)) {
        return bin;
      }
      let error = new Error(
        `File at path "${bin}" does not exist, or is not executable`
      );
      error.errorCode = SubprocessConstants.ERROR_BAD_EXECUTABLE;
      throw error;
    }

    let dirs = [];
    if (typeof environment.PATH === "string") {
      dirs = environment.PATH.split(":");
    }

    for (let dir of dirs) {
      let path = PathUtils.join(dir, bin);

      if (await this.isExecutableFile(path)) {
        return path;
      }
    }
    let error = new Error(`Executable not found: ${bin}`);
    error.errorCode = SubprocessConstants.ERROR_BAD_EXECUTABLE;
    throw error;
  },

  connectRunning(options) {
    return Process.fromRunning(options);
  },
};

export var SubprocessImpl = SubprocessUnix;
PK