ubuntu-cpc: rework image artifact cleanup

The livecd.ubuntu-cpc.ext4 that is present in each build (plus kernel
and initrd) are not renamed from /build/binary/boot/filsystem.ext4
and friends until after the binary hooks are run, so this patch moves
from trying to perform this cleanup in a binary hook.  Now the cleanup
will be run at the end of live-build/binary for the ubuntu-cpc project.

live-build/auto/build

@@ -1018,3 +1018,8 @@ if [ -f "config/magic-proxy.pid" ]; then
     iptables -t nat -D OUTPUT -p tcp --dport 80 -m owner ! --uid-owner daemon \
         -j REDIRECT --to 8080
 fi
+
+case $PROJECT in
+    ubuntu-cpc)
+        config/hooks.d/remove-implicit-artifacts
+esac

live-build/ubuntu-cpc/hooks.d/base/final.binary

@@ -1,47 +0,0 @@
-#!/usr/bin/env python3
-#-*- encoding: utf-8 -*-
-"""
-The final hook is run after all other binary hooks.
-"""
-import glob
-import os
-
-
-def remove_implicit_files():
-    """
-    Remove output files not created by explicitly specified image targets
-
-    This uses the 'explicit_provides' file generated by the 'make-hooks'
-    script.  If the file is empty, all output will be saved.
-    """
-    explicit = set()
-    with open('./config/hooks/explicit_provides', 'r', encoding='utf-8') as fp:
-        for filename in fp:
-            explicit.add(filename.rstrip())
-
-    if not explicit:
-        print('remove_implicit_files: explicit_provides is empty '
-              'all binary output will be included')
-        quit()
-
-    all = set(glob.glob('livecd.ubuntu-cpc.*'))
-    implicit = all - explicit
-
-    print('remove_implicit_files: all artifacts considered: {}'.format(all))
-    print('remove_implicit_files: explict artifacts to keep: '
-          '{}'.format(explicit))
-    print('remove_implicit_files: implicit artifacts to remove: '
-          '{}'.format(implicit))
-
-    for file in implicit:
-        print('remove_implicit_files: removing {} '
-              '{} bytes'.format(file, os.stat(file).st_size))
-        if os.path.islink(file):
-            os.unlink(file)
-        elif os.path.isfile(file):
-            os.remove(file)
-
-
-if __name__ == "__main__":
-    print('Running {}'.format(__file__))
-    remove_implicit_files()

live-build/ubuntu-cpc/hooks.d/make-hooks

@@ -42,11 +42,10 @@ specified multiple times.  The field is used by this script to generate a list
 of output files created explicitly by the named image targets.  The list is
 saved to the "explicit_provides" file in the hooks output directory. In
 the case of the "all" target this list would be empty.  This list is
-consumed by the "final.binary" hook file.
+consumed by the "remove-implicit-artifacts" which is run at the end of the build.
 
 The final.binary hook is always included as the last hook(s) if it exists,
-it should not be specified in series files.  It can be included from "base"
-and/or "extra" directories with the final hook in "exta" running last.
+it should not be specified in series files.
 
 ACHTUNG: live build runs scripts with the suffix ".chroot" in a batch separate
 from scripts ending in ".binary". Even if you arrange them interleaved in your
@@ -215,11 +214,10 @@ class MakeHooks:
             sys.stderr.write("WARNING: Hooks directory exists and is not empty.\n")
         os.makedirs(self._hooks_dir, exist_ok=True)
 
-        # Always add final.binary hooks if they exist
-        for subdir in ["base", "extra"]:
-            final_hook = os.path.join(self._script_dir, subdir, "final.binary")
-            if os.path.exists(final_hook) and os.path.isfile(final_hook):
-                self._hooks_list.append("base/final.binary")
+        # Always add final.binary hook if it exists
+        final_hook = os.path.join(self._script_dir, "base/final.binary")
+        if os.path.exists(final_hook) and os.path.isfile(final_hook):
+            self._hooks_list.append("base/final.binary")
 
         for counter, hook in enumerate(self._hooks_list, start=1):
             hook_basename = os.path.basename(hook)
@@ -239,13 +237,13 @@ class MakeHooks:
 
     def create_explicit_provides(self):
         """
-        Create a file named "explicit_provides" in self._hooks_dir
+        Create a file named "explicit_provides" in self._script_dir
         listing all files named on "provides" in the series files of
         targets explicitly named by the user.  The file is created but
         left empty if there are no explict "provides" keywords in the
         targets (this is the case for 'all')
         """
-        with open(os.path.join(self._hooks_dir, "explicit_provides"), "w",
+        with open(os.path.join(self._script_dir, "explicit_provides"), "w",
                   encoding="utf-8") as fp:
             empty = True
             for provides in self._provides:

live-build/ubuntu-cpc/hooks.d/remove-implicit-artifacts

@@ -0,0 +1,40 @@
+#!/usr/bin/env python3
+#-*- encoding: utf-8 -*-
+"""
+Remove output files not created by explicitly specified image targets
+
+This uses the 'explicit_provides' file generated by the 'make-hooks'
+script.  If the file is empty, all output will be saved.
+"""
+import glob
+import os
+
+if __name__ == "__main__":
+    print('Running {}'.format(__file__))
+    scriptname = os.path.basename(__file__)
+    explicit = set()
+    with open('./config/hooks.d/explicit_provides', 'r',
+              encoding='utf-8') as fp:
+        for filename in fp:
+            explicit.add(filename.rstrip())
+
+    if not explicit:
+        print('{}: explicit_provides is empty. '
+              'All binary output will be included'.format(scriptname))
+        quit()
+
+    all = set(glob.glob('livecd.ubuntu-cpc.*'))
+    implicit = all - explicit
+
+    print('{}: all artifacts considered: {}'.format(scriptname, all))
+    print('{}: explict artifacts to keep: {}'.format(scriptname, explicit))
+    print('{}: implicit artifacts to remove: {}'.format(scriptname, implicit))
+
+    for file in implicit:
+        if os.path.islink(file):
+            print('{}: unlinking {}'.format(scriptname, file))
+            os.unlink(file)
+        elif os.path.isfile(file):
+            print('{}: removing {} '
+                  '{} bytes'.format(scriptname, file, os.stat(file).st_size))
+            os.remove(file)