Optional --rsync parameter for pmbootstrap install only copies the diff (#1151)

Should reduce wear of sd card. Example usage:
pmbootstrap install --sdcard=/dev/mmcblk0 --no-fde --rsync
More rsync output with pmbootstrap -v.

pmb/helpers/frontend.py

@@ -194,6 +194,12 @@ def initfs(args):
 
 
 def install(args):
+    if args.rsync and args.full_disk_encryption:
+        raise ValueError("Installation using rsync is not compatible with full"
+                         " disk encryption.")
+    if args.rsync and not args.sdcard:
+        raise ValueError("Installation using rsync only works on sdcard.")
+
     pmb.install.install(args)
 
 

pmb/install/__init__.py

@@ -19,3 +19,4 @@ along with pmbootstrap.  If not, see <http://www.gnu.org/licenses/>.
 from pmb.install.install import install
 from pmb.install.partition import partition
 from pmb.install.format import format
+from pmb.install.partition import partitions_mount

pmb/install/format.py

@@ -49,14 +49,20 @@ def format_and_mount_root(args):
 
 
 def format_and_mount_pm_crypt(args):
+    # Block device
     if args.full_disk_encryption:
         device = "/dev/mapper/pm_crypt"
     else:
         device = "/dev/installp2"
+
+    # Format
+    if not args.rsync:
+        logging.info("(native) format " + device)
+        pmb.chroot.root(args, ["mkfs.ext4", "-F", "-q", "-L", "pmOS_root", device])
+
+    # Mount
     mountpoint = "/mnt/install"
-    logging.info("(native) format " + device + " (ext4), mount to " +
-                 mountpoint)
-    pmb.chroot.root(args, ["mkfs.ext4", "-F", "-q", "-L", "pmOS_root", device])
+    logging.info("(native) mount " + device + " to " + mountpoint)
     pmb.chroot.root(args, ["mkdir", "-p", mountpoint])
     pmb.chroot.root(args, ["mount", device, mountpoint])
 

pmb/install/install.py

@@ -86,9 +86,18 @@ def copy_files_from_chroot(args):
             continue
         folders += [os.path.basename(path)]
 
-    # Run the copy command
-    pmb.chroot.root(args, ["cp", "-a"] + folders + ["/mnt/install/"],
-                    working_dir=mountpoint)
+    # Update or copy all files
+    if args.rsync:
+        pmb.chroot.apk.install(args, ["rsync"])
+        rsync_flags = "-a"
+        if args.verbose:
+            rsync_flags += "vP"
+        pmb.chroot.root(args, ["rsync", rsync_flags, "--delete"] + folders + ["/mnt/install/"],
+                        working_dir=mountpoint)
+        pmb.chroot.root(args, ["rm", "-rf", "/mnt/install/home"])
+    else:
+        pmb.chroot.root(args, ["cp", "-a"] + folders + ["/mnt/install/"],
+                        working_dir=mountpoint)
 
 
 def copy_files_other(args):
@@ -100,7 +109,7 @@ def copy_files_other(args):
     for key in glob.glob(args.work + "/config_apk_keys/*.pub"):
         pmb.helpers.run.root(args, ["cp", key, rootfs + "/etc/apk/keys/"])
 
-    # Create /home/{user}
+    # Create /home/{user} from /etc/skel
     homedir = rootfs + "/home/" + args.user
     pmb.helpers.run.root(args, ["mkdir", rootfs + "/home"])
     pmb.helpers.run.root(args, ["cp", "-a", rootfs + "/etc/skel", homedir])
@@ -196,8 +205,11 @@ def install_system_image(args):
     logging.info("*** (3/5) PREPARE INSTALL BLOCKDEVICE ***")
     pmb.chroot.shutdown(args, True)
     (size_image, size_boot) = get_subpartitions_size(args)
-    pmb.install.blockdevice.create(args, size_image)
-    pmb.install.partition(args, size_boot)
+    if not args.rsync:
+        pmb.install.blockdevice.create(args, size_image)
+        pmb.install.partition(args, size_boot)
+    pmb.install.partitions_mount(args)
+
     if args.full_disk_encryption:
         logging.info("WARNING: Full disk encryption is enabled!")
         logging.info("Make sure that osk-sdl has been properly configured for your device")

pmb/install/partition.py

@@ -81,6 +81,3 @@ def partition(args, size_boot):
     for command in commands:
         pmb.chroot.root(args, ["parted", "-s", "/dev/install"] +
                         command, check=False)
-
-    # Mount new partitions
-    partitions_mount(args)

pmb/parse/arguments.py

@@ -266,6 +266,8 @@ def arguments():
                              " chroot and install to sdcard or image file")
     install.add_argument("--sdcard", help="path to the sdcard device,"
                          " eg. /dev/mmcblk0")
+    install.add_argument("--rsync", help="update the sdcard using rsync,"
+                         " only works with --no-fde", action="store_true")
     install.add_argument("--cipher", help="cryptsetup cipher used to"
                          " encrypt the system partition, eg. aes-xts-plain64")
     install.add_argument("--iter-time", help="cryptsetup iteration time (in"