keys.scala, etc.: Make merging public keys have a progress bar.

[tripe-android] / app.scala

/* -*-scala-*-
 *
 * Setting up the Android environment
 *
 * (c) 2018 Straylight/Edgeware
 */

/*----- Licensing notice --------------------------------------------------*
 *
 * This file is part of the Trivial IP Encryption (TrIPE) Android app.
 *
 * TrIPE is free software: you can redistribute it and/or modify it under
 * the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 3 of the License, or (at your
 * option) any later version.
 *
 * TrIPE is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with TrIPE.  If not, see <https://www.gnu.org/licenses/>.
 */

package uk.org.distorted.tripe; package object app {

/*----- Imports -----------------------------------------------------------*/

import java.io.{File, IOException};

import scala.collection.mutable.HashMap;

import android.content.Context; import Context.MODE_WORLD_READABLE;
import android.os.Build; import Build.{CPU_ABI, CPU_ABI2};
import android.util.Log;

import sys.FileImplicits._;

/*----- Regular expressions for parsing the `.installed file --------------*/

private final val RX_COMMENT = """(?x) ^ \s* (?: \# .* )? $""".r;
private final val RX_KEYVAL = """(?x) ^ \s*
      ([-\w]+)
      (?:\s+(?!=)|\s*=\s*)
      (|\S|\S.*\S)
      \s* $""".r;

/*----- Main code ---------------------------------------------------------*/

private final val TAG = "TrIPE";

var root: File = null;

private def install(ctx: Context, inst: HashMap[String, String]) {

  /* First, figure out which ABIs are wanted on this device.  Unfortunately,
   * the good way of doing this isn't available in our minimum API level, so
   * we must use reflection.
   */
  val abis = try {
    classOf[Build].getField("SUPPORTED_ABIS").get(null).
      asInstanceOf[Array[String]]
  } catch { case _: NoSuchFieldException =>
    Array(CPU_ABI, CPU_ABI2) flatMap {
      case null | "" => None
      case s => Some(s)
    }
  }
  Log.d(TAG, s"abis = ${abis.mkString(", ")}");

  /* Clear out whatever might be there already. */
  val bindir = root/"bin";
  bindir.rmTree();
  bindir.mkdir_!();

  /* Now extract each of our binaries using the best available ABI. */
  val assets = ctx.getAssets;
  for (abi <- abis) {
    val binsrc = s"bin/$abi";
    for (base <- assets.list(binsrc)) {
      val outfile = bindir/base;
      if (!outfile.exists_!) {
	Log.d(TAG, s"install: extract `$base' using abi `$abi'");
	outfile.withOutput { out =>
	  closing(assets.open(s"$binsrc/$base")) { in =>
	    for ((buf, n) <- blocks(in)) out.write(buf, 0, n);
	  }
	}
      }
      outfile.chmod_!(0x1ed);
    }
  }

  /* Write out a new install file. */
  val infofile = root/".installed";
  val newinfofile = root/".installed.new";
  newinfofile.withWriter { out =>
    out.write(s"""### -*-conf-*-

uuid = ${ctx.getString(R.string.auto_build_uuid)}
""");
  }
  newinfofile.rename_!(infofile);
}

def setup(ctx: Context) {

  /* Make our root directory and remember where it is. */
  root = ctx.getFilesDir;
  if (!root.isdir_!) {
    throw new IOException("system failed to create `files' " +
			  "(but didn't tell us)");
  }

  /* Find out which build, if any, corresponds to what's there already. */
  val inst = HashMap[String, String]();
  try { root/".installed" withReader { in =>
    var lno = 1;
    for (line <- lines(in)) {
      line match {
	case RX_COMMENT() => ok;
	case RX_KEYVAL(k, v) => inst(k) = v;
	case _ => Log.w(TAG, s".installed:$lno: ignored unparseable line");
      }
      lno += 1;
    }
  } } catch {
    case e: IOException =>
      Log.w(TAG, s".installed: I/O error: ${e.getMessage}");
  }

  /* If this doesn't match, then we have some work to do. */
  if (inst.getOrElse("uuid", "<nothing>") !=
      ctx.getString(R.string.auto_build_uuid))
    install(ctx, inst);
}

/*----- That's all, folks -------------------------------------------------*/

}