Use working directory for user/group resolution (#1320)

To handle where the ~/.vagrant.d global state directory for a user
doesn't exist, and thus specifying it as part of the docker run command
will result in the docker daemon creating it with root ownership.

Switch to using the working directory for user/group resolution,
searching for the Vagrantfile in the starting path and then working
up the tree. If it's not found default to the original starting path.

Combined with checking if the mounted vdir is empty, use the resolved
user/group based on the Vagrantfile and working directory to modify the
newly created directory to belong to the running user. Subsequently
ensure that the directories referenced via symlinks are created if they
don't exist.

Fixes: #1191
Closes: #1254

README.md

@@ -131,8 +131,8 @@ docker run -it --rm \
   -e LIBVIRT_DEFAULT_URI \
   -v /var/run/libvirt/:/var/run/libvirt/ \
   -v ~/.vagrant.d:/.vagrant.d \
-  -v $(pwd):$(pwd) \
+  -v $(realpath "${PWD}"):${PWD} \
-  -w $(pwd) \
+  -w $(realpath "${PWD}") \
   --network host \
   vagrantlibvirt/vagrant-libvirt:latest \
     vagrant status
@@ -141,13 +141,12 @@ docker run -it --rm \
 It's possible to define an alias in `~/.bashrc`, for example:
 ```bash
 alias vagrant='
-  mkdir -p ~/.vagrant.d/{boxes,data,tmp}; \
   docker run -it --rm \
     -e LIBVIRT_DEFAULT_URI \
     -v /var/run/libvirt/:/var/run/libvirt/ \
     -v ~/.vagrant.d:/.vagrant.d \
-    -v $(pwd):$(pwd) \
+    -v $(realpath "${PWD}"):${PWD} \
-    -w $(pwd) \
+    -w $(realpath "${PWD}") \
     --network host \
     vagrantlibvirt/vagrant-libvirt:latest \
     vagrant'

entrypoint.sh

@@ -13,43 +13,63 @@ then
     exit 2
 fi
 
-for dir in boxes data tmp
-do
-    # if the directory hasn't been explicitly mounted over, remove it.
-    if [[ -e "/vagrant/${dir}/.remove" ]]
-    then
-        rm -rf /vagrant/${dir}
-        ln -s ${vdir}/${dir} /vagrant/${dir}
-    fi
-done
-
 vdir_mnt=$(stat -c %m ${vdir})
 case "${vdir_mnt%%/}" in
     /*)
         # user mounted vagrant home is not mounted on /, so
         # presumably it is a mount bind or mounted volume and should
-        # be able to determine suitable uid/gid
+        # be able to persist boxes and machine index.
+        #
         ;;
     *)
-        echo "${vdir} is not set to a bind mounted volume, will not be able"
+        echo -n "${vdir} is not set to a bind mounted volume, may not be able "
-        echo "to automatically determine suitable uid/gid to execute under."
+        echo -n "to persist the machine index which may result in some unexpected "
-        if [[ -z "${USER_UID:-}" ]] || [[ -z "${USER_GID:-}" ]]
+        echo "behaviour."
-        then
-            echo "USER_UID and USER_GID must be explicitly provided when"
-            echo "auto-detection is unable to be used"
-
-            exit 2
-        fi
         ;;
 esac
 
-USER_UID=${USER_UID:-$(stat -c %u ${vdir})} || exit 3
+# To determine default user to use search for the Vagrantfile starting with
-USER_GID=${USER_GID:-$(stat -c %g ${vdir})} || exit 3
+# the current working directory. If it can't be found, use the owner/group
-if [[ ${USER_UID} -eq 0 ]] && [[ -z "${IGNORE_RUN_AS_ROOT:-}" ]]
+# from the current working directory anyway
+vagrantfile="${VAGRANT_VAGRANTFILE:-Vagrantfile}"
+path="$(pwd)"
+while [[ "$path" != "" && ! -e "$path/$1" ]]
+do
+    path=${path%/*}
+done
+
+if [[ "$path" == "" ]]
 then
-    echo "WARNING! Running as root, if this breaks, you get to keep both pieces"
+    path="$(pwd)"
 fi
 
+USER_UID=${USER_UID:-$(stat -c %u ${path})} || exit 3
+USER_GID=${USER_GID:-$(stat -c %g ${path})} || exit 3
+if [[ ${USER_UID} -eq 0 ]]
+then
+    if [[ -z "${IGNORE_RUN_AS_ROOT:-}" ]]
+    then
+        echo "WARNING! Running as root, if this breaks, you get to keep both pieces"
+    fi
+else
+    vdir_uid=$(stat -c %u ${vdir})
+    if [[ "${vdir_uid}" != "${USER_UID}" ]]
+    then
+        if [[ -z "$(ls -A ${vdir})" ]]
+        then
+            # vdir has just been created and is owned by the wrong user
+            # modify the ownership to allow the required directories to
+            # be created
+            chown ${USER_UID}:${USER_GID} ${vdir}
+        else
+            echo -n "ERROR: Attempting to use a directory on ${vdir} that is not "
+            echo -n "owned by the user that owns ${path}/${vagrantfile} is not "
+            echo "supported!"
+
+            exit 2
+        fi
+    fi
+fi
 
 export USER=vagrant
 export GROUP=users
@@ -78,6 +98,19 @@ then
     ${USERCMD} --shell /bin/bash -u ${USER_UID} -g ${USER_GID} -o -c "" -m ${USER} >/dev/null 2>&1 || exit 3
 fi
 
+# Perform switching in of boxes, data directory containing machine index
+# and temporary directory from the user mounted environment
+for dir in boxes data tmp
+do
+    # if the directory hasn't been explicitly mounted over, remove it.
+    if [[ -e "/vagrant/${dir}/.remove" ]]
+    then
+        rm -rf /vagrant/${dir}
+        [[ ! -e ${vdir}/${dir} ]] && gosu ${USER} mkdir ${vdir}/${dir}
+        ln -s ${vdir}/${dir} /vagrant/${dir}
+    fi
+done
+
 # make sure the directories can be written to by vagrant otherwise will
 # get a start up error
 find ${VAGRANT_HOME} -maxdepth 1 ! -exec chown -h ${USER}:${GROUP} {} \+