feat: create dir at -r/-w path if it does not exist

Author: rti

tests.nix

@@ -421,6 +421,17 @@ pkgs.nixosTest {
         wrap -p bash -c 'test -d "$HOME" -a -w "$HOME" && echo ok' | grep '^ok$' ||
           (echo 'Unexpected: $HOME not created or not writable inside sandbox'; false)
       """))
+
+    with subtest("r/w shared directory is created if it does not exist"):
+      machine.succeed(as_alice("""
+        export SOME_DIR=/tmp/some-dir
+        rm -rf "$SOME_DIR"
+
+        wrap -p -e SOME_DIR -r "$SOME_DIR" bash -c 'test -d "$SOME_DIR" && echo ok' | grep '^ok$' ||
+          (echo 'Unexpected: -r $SOME_DIR does not create directory'; false)
+        wrap -p -e SOME_DIR -w "$SOME_DIR" bash -c 'test -d "$SOME_DIR" && echo ok' | grep '^ok$' ||
+          (echo 'Unexpected: -w $SOME_DIR does not create directory'; false)
+      """))
   '';
 }
 

wrap.sh

@@ -179,11 +179,17 @@ while getopts "r:w:e:abcdfhmnpuv" opt; do
 
   # bind / mount a path readonly in sandbox to the same path as host
   r)
+    # Create a directory if the path does not exist
+    mkdir -p "$OPTARG" || true
+
     bwrap_opts+=(--ro-bind "$OPTARG" "$OPTARG")
     ;;
 
   # bind / mount a path read/write in sandbox to the same path as host
   w)
+    # Create a directory if the path does not exist
+    mkdir -p "$OPTARG" || true
+
     bwrap_opts+=(--bind "$OPTARG" "$OPTARG")
     ;;
 
@@ -307,6 +313,7 @@ while getopts "r:w:e:abcdfhmnpuv" opt; do
     usage
     exit 1
     ;;
+
   :)
     usage
     exit 1