create and maintain release from /usr/src

Author: gronke

README.md

@@ -49,6 +49,25 @@ jail.create("11.1-RELEASE")
 
 Libiocage comes bundles with a CLI tool called `ioc`. It is inspired by the command line interface of [iocage](https://github.com/iocage/iocage) but meant to be developed along with the library and to spike on new features.
 
+### Custom Release (e.g. running -CURRENT)
+
+#### Initially create release dataset
+
+```sh
+zfs create zroot/iocage/releases/custom/root
+cd /usr/src
+#install your source tree
+make installworld DESTDIR=/iocage/releases/custom/root
+make distribution DESTDIR=/iocage/releases/custom/root
+ioc fetch -r custom -b
+```
+
+#### Update the installation after recompile
+```sh
+make installworld DESTDIR=/iocage/releases/custom/root
+ioc fetch -r custom -b
+```
+
 ## Development
 
 ### Install Development Dependencies

iocage/cli/fetch.py

@@ -52,6 +52,14 @@
 # Compat
 @click.option("--http", "-h", default=False,
               help="Have --server define a HTTP server instead.", is_flag=True)
+# Basejail Update
+@click.option(
+    "--copy-basejail-only",
+    "-b",
+    is_flag=True,
+    default=False,
+    help="Update basejail after changes"
+)
 # Compat files
 @click.option("--files", multiple=True,
               help="Specify the files to fetch from the mirror. "
@@ -78,6 +86,13 @@ def cli(ctx, **kwargs):
             logger.error(f"Invalid Release '{release_input}'")
             exit(1)
 
+    if kwargs["copy_basejail_only"] is True:
+        try:
+            release.update_base_release()
+            exit(0)
+        except iocage.lib.errors.IocageException:
+            exit(1)
+
     url_or_files_selected = False
 
     if is_option_enabled(kwargs, "url"):

iocage/lib/Release.py

@@ -435,7 +435,7 @@ def fetch(self, update=None, fetch_updates=None):
 
         if release_changed:
             yield releaseCopyBaseEvent.begin()
-            self._update_zfs_base()
+            self.update_base_release()
             yield releaseCopyBaseEvent.end()
         else:
             yield releaseCopyBaseEvent.skip(message="release unchanged")
@@ -864,7 +864,7 @@ def _update_name_from_dataset(self):
         if self.dataset is not None:
             self.name = self.dataset.name.split("/")[-2:-1]
 
-    def _update_zfs_base(self):
+    def update_base_release(self):
 
         base_dataset = self.zfs.get_or_create_dataset(self.base_dataset_name)