[OE-core] [PATCH 3/5] rootfs.py: support ipk incremental image generation

[Hongxu Jia]

While incremental image generation enabled, if previous image existed,
it restores the opkg database. Based on the previous image, it gets what
need to remove for the current and remove them.

The newly added and upgraded packages will be done since opkg install
invoked.

[YOCTO #1894]

Signed-off-by: Hongxu Jia <hongxu.jia at windriver.com>
---
 meta/lib/oe/rootfs.py | 50 +++++++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 47 insertions(+), 3 deletions(-)

diff --git a/meta/lib/oe/rootfs.py b/meta/lib/oe/rootfs.py
index d149ca3..5561bb9 100644
--- a/meta/lib/oe/rootfs.py
+++ b/meta/lib/oe/rootfs.py
@@ -438,13 +438,25 @@ class OpkgRootfs(Rootfs):
     def __init__(self, d, manifest_dir):
         super(OpkgRootfs, self).__init__(d)
 
-        bb.utils.remove(self.image_rootfs, True)
-        bb.utils.remove(self.d.getVar('MULTILIB_TEMP_ROOTFS', True), True)
         self.manifest = OpkgManifest(d, manifest_dir)
         self.opkg_conf = self.d.getVar("IPKGCONF_TARGET", True)
         self.pkg_archs = self.d.getVar("ALL_MULTILIB_PACKAGE_ARCHS", True)
 
-        self.pm = OpkgPM(d, self.image_rootfs, self.opkg_conf, self.pkg_archs)
+        self.inc_opkg_image_gen = self.d.getVar('INC_IPK_IMAGE_GEN', True)
+        if self.inc_opkg_image_gen != "1":
+            bb.utils.remove(self.image_rootfs, True)
+            self.pm = OpkgPM(d,
+                             self.image_rootfs,
+                             self.opkg_conf,
+                             self.pkg_archs)
+        else:
+            self.pm = OpkgPM(d,
+                             self.image_rootfs,
+                             self.opkg_conf,
+                             self.pkg_archs)
+            self.pm.recovery_packaging_data()
+
+        bb.utils.remove(self.d.getVar('MULTILIB_TEMP_ROOTFS', True), True)
 
     """
     This function was reused from the old implementation.
@@ -508,6 +520,32 @@ class OpkgRootfs(Rootfs):
 
         self._multilib_sanity_test(dirs)
 
+    '''
+    While ipk incremental image generation is enabled, it will remove the
+    unneeded pkgs by comparing the new install solution manifest and the
+    old installed manifest.
+    '''
+    def _create_incremental(self, pkgs_initial_install):
+        if self.inc_opkg_image_gen == "1":
+
+            pkgs_to_install = list()
+            for pkg_type in pkgs_initial_install:
+                pkgs_to_install += pkgs_initial_install[pkg_type]
+
+            installed_manifest = self.pm.load_old_install_solution()
+            solution_manifest = self.pm.dump_install_solution(pkgs_to_install)
+
+            pkg_to_remove = list()
+            for pkg in installed_manifest:
+                if pkg not in solution_manifest:
+                    pkg_to_remove.append(pkg)
+
+            self.pm.update()
+
+            if pkg_to_remove != []:
+                bb.note('incremental removed: %s' % ' '.join(pkg_to_remove))
+                self.pm.remove(pkg_to_remove)
+
     def _create(self):
         pkgs_to_install = self.manifest.parse_initial_manifest()
         opkg_pre_process_cmds = self.d.getVar('OPKG_PREPROCESS_COMMANDS', True)
@@ -518,6 +556,9 @@ class OpkgRootfs(Rootfs):
         if (self.d.getVar('BUILD_IMAGES_FROM_FEEDS', True) or "") != "1":
             self.pm.write_index()
 
+        if self.inc_opkg_image_gen == "1":
+            self._create_incremental(pkgs_to_install)
+
         execute_pre_post_process(self.d, opkg_pre_process_cmds)
 
         self.pm.update()
@@ -540,6 +581,9 @@ class OpkgRootfs(Rootfs):
         execute_pre_post_process(self.d, opkg_post_process_cmds)
         execute_pre_post_process(self.d, rootfs_post_install_cmds)
 
+        if self.inc_opkg_image_gen == "1":
+            self.pm.backup_packaging_data()
+
     def _get_delayed_postinsts(self):
         pkg_list = []
         status_file = os.path.join(self.image_rootfs,
-- 
1.8.1.2