Ensure access to tty within container (close #3).

And return exit value of command if invoked as `switch biolinux blastp ...`.

Signed-off-by: Anurag Priyam <[email protected]>

Dockerfiles/baseimage/_init

@@ -14,8 +14,9 @@ if [ $? -ne 0 ]; then
   passwd -d $user &> /dev/null
 fi
 
-if [ $# -eq 0 ]; then
-  su -l $user -s $shell -c "[ -d $cwd ] && cd $cwd; exec $shell"
-else
-  su -l $user -s $shell -c "[ -d $cwd ] && cd $cwd; $*"
-fi
+exec sudo -u $user -i exec $shell -c \
+"
+  [ -d $cwd  ] && cd $cwd;
+  [ $# -gt 0 ] && exec $*;
+  exec $shell;
+"

lib/switch.rb

@@ -31,7 +31,7 @@ def to_s
 
   include Timeout
 
-  # Captures a docker image.
+  # Captures a docker image's metadata.
   Image = Struct.new :repository, :tag, :id, :created, :size
 
   class Image
@@ -147,19 +147,14 @@ def initialize(package, command = [])
     # images on the user's system. It must be noted though that other program
     # may use the same prefix, and thus our images aren't truly isolated.
     @imgname = "switch/#{@package.gsub('_', ':')}"
-    # We don't give up the pid untill docker completes. Thus appending pid to
-    # the package name gurantees us a unique container name. If we were using
-    # exec or fork, we would have to worry about pids being recycled.
+
     @cntname = "#@package-#{Process.pid}"
 
     exec
   end
 
   attr_reader :package, :command, :imgname, :cntname
 
-  # NOTE:
-  #   Doesn't really exec. Our ruby proecess waits till docker process started
-  #   has been terminated.
   def exec
     ping and build and switch
   rescue ENODKR, ENOPKG => e
@@ -172,7 +167,7 @@ def exec
   def switch
     cmdline = "docker run --name #{cntname} --hostname #{cntname} -it --rm=true" \
       " #{mountargs} #{imgname} #{userargs} #{command}"
-    system cmdline
+    Kernel.exec cmdline
   end
 
   def build