lib.js

// Copyright 2018 MaidSafe.net limited.
//
// This SAFE Network Software is licensed to you under
// the MIT license <LICENSE-MIT or http://opensource.org/licenses/MIT> or
// the Modified BSD license <LICENSE-BSD or https://opensource.org/licenses/BSD-3-Clause>,
// at your option.
//
// This file may not be copied, modified, or distributed except according to those terms.
//
// Please review the Licences for the specific language governing permissions and limitations
// relating to use of the SAFE Network Software.


const path = require('path');
const fs = require('fs');
const FFI = require('ffi');
const { getSafeAppLibFilename } = require('../helpers');
const { getSystemUriLibFilename } = require('../helpers');
const os = require('os');

const currentDir = path.dirname(__filename);

const api = require('./api');
const makeError = require('./_error.js');
const errConst = require('./../error_const');
const ffi = {};

const RTLD_NOW = FFI.DynamicLibrary.FLAGS.RTLD_NOW;
const RTLD_GLOBAL = FFI.DynamicLibrary.FLAGS.RTLD_GLOBAL;
const mode = RTLD_NOW | RTLD_GLOBAL;
let lib = null;

ffi.init = (options) => {
  try {
    lib = FFI.DynamicLibrary(getSafeAppLibFilename(currentDir, options), mode);

    api.forEach((mod) => {
      if (!lib) {
        throw new Error('Native library not initialised');
      }
      if (mod.functions){
        for (const key in mod.functions) {
          const funcDefinition = mod.functions[key];

          ffi[key] = FFI.ForeignFunction(lib.get(key),
                                         funcDefinition[0],
                                         funcDefinition[1])
        }
      }
      if (mod.api) {
        for (const key in mod.api) {
          ffi[key].fn_name = key;
          let fn = mod.api[key](ffi, ffi[key]);
          fn.fn_name = "[mapped]" + key;
          ffi[key] = fn;
        }
      //   Object.assign(mappings, mod.api);
      }
      if (mod.helpersForNative) {
        for (const key in mod.helpersForNative) {
          let fn = mod.helpersForNative[key];
          fn.fn_name = "[mapped]" + key;
          ffi[key] = fn;
        }
      }
    });
    // FIXME: As long as `safe-app` doesn't expose system uri itself, we'll
    // patch it directly on it. This should later move into its own sub-module
    // and take care of mobile support for other platforms, too.
    const mobileEnv = !fs.existsSync(getSystemUriLibFilename(currentDir));
    if (!mobileEnv) {
      require('./_system_uri')(ffi, options);
    }
  } catch(e) {
    console.error(e)
    throw makeError(errConst.FAILED_TO_LOAD_LIB.code,
        errConst.FAILED_TO_LOAD_LIB.msg(e.toString()));
  }
};

module.exports = ffi;