Split from nodeos-mount-filesystems

Author: piranna

lib/basicEnvironment.js

@@ -1,3 +1,104 @@
-exports.basicEnvironment = require('./basicEnvironment')
-exports.mountUsersFS     = require('./mountUsersFS')
-exports.prepareSessions  = require('./prepareSessions')
+const fs = require('fs')
+
+const each      = require('async/each')
+const jocker    = require('jocker')
+const rimraf    = require('rimraf').sync
+const startRepl = require('nodeos-mount-utils').startRepl
+
+const jocker_root = require('./jocker_root')
+
+
+/**
+ * Filter folders that are valid user `$HOME`
+ * @access private
+ * @param  {String}  user The name of the user
+ * @return {Boolean}      Returns true If the first char is not a dot
+ *                        and not `root` and not ´lost+found´
+ */
+function filterUser(user)
+{
+  return user[0] !== '.' && user !== 'root' && user !== 'lost+found'
+}
+
+/**
+ * Overlays the users filesystem
+ *
+ * @param {String} usersFolder The path to folder of the users
+ * @param {Function} callback
+ */
+function usersSessions(usersFolder, callback)
+{
+  function done(error)
+  {
+    // Remove the modules from initramfs to free memory
+    // rimraf('/lib/node_modules')
+    rimraf('/lib/node_modules/jocker')
+
+    // Make '/usr' a opaque folder (OverlayFS feature)
+    rimraf('/usr')
+
+    callback(error)
+  }
+
+  // Mount users directories and exec their init files
+  fs.readdir(usersFolder, function(error, users)
+  {
+    if(error) return done(error)
+
+    each(users.filter(filterUser), function(username, callback)
+    {
+      jocker.run(usersFolder+'/'+username, '/init', {PATH: '/bin'}, callback)
+    },
+    done)
+  })
+}
+
+
+//
+// Public API
+//
+
+/**
+ * Prepares the session and checks if the users filesystem has a root account,
+ * if not check if `/proc/cmdline` has the single key
+ * It deletes the `root`, `rootfstype` and `vga` environment variables
+ * and adds `NODE_PATH` to it.
+ * @access private
+ * @return {Repl} Returns either a repl or a error if the error contains
+ *                a `ENOENT` code
+ */
+function prepareSessions(home, single, callback)
+{
+  const upperdir = home+'/root'
+
+  // Check if users filesystem has an administrator account
+  fs.readdir(upperdir, function(error)
+  {
+    if(error)
+    {
+      if(error.code !== 'ENOENT') return callback(error)
+
+      return usersSessions(home, callback)
+    }
+
+    // There's an administrator account, prepare it first
+    jocker_root.create(upperdir, function(error, newHome)
+    {
+      if(error) return callback(error)
+
+      // Enter administrator mode
+      if(single) return startRepl('Administrator mode')
+
+      // Execute `root` user init in un-priviledged environment
+      jocker.exec(home, '/init', {PATH: '/bin'}, function(error)
+      {
+        if(error) console.warn(error)
+
+        usersSessions(newHome, callback)
+      })
+    })
+  })
+}
+
+
+module.exports = prepareSessions