pmb.flasher/export: Add --no-install option to skip kernel/initfs update (!1863)

At the moment, pmbootstrap updates the kernel and the initfs whenever
using the flasher or export. This is useful, but sometimes you just want
to boot exactly the same kernel several times. In that case, having to wait
several seconds for the (redundant) update to complete is quite annoying.

Add a --no-install option that allows skipping the kernel/initfs update.

pmb/export/frontend.py

@@ -22,8 +22,9 @@ def frontend(args):
                      " install' first (without the 'sdcard' parameter).")
 
     # Rebuild the initramfs, just to make sure (see #69)
-    flavor = pmb.helpers.frontend._parse_flavor(args)
-    pmb.chroot.initfs.build(args, flavor, "rootfs_" + args.device)
+    flavor = pmb.helpers.frontend._parse_flavor(args, args.autoinstall)
+    if args.autoinstall:
+        pmb.chroot.initfs.build(args, flavor, "rootfs_" + args.device)
 
     # Do the export, print all files
     logging.info("Export symlinks to: " + target)

pmb/flasher/frontend.py

@@ -31,8 +31,9 @@ import pmb.parse.kconfig
 
 def kernel(args):
     # Rebuild the initramfs, just to make sure (see #69)
-    flavor = pmb.helpers.frontend._parse_flavor(args)
-    pmb.chroot.initfs.build(args, flavor, "rootfs_" + args.device)
+    flavor = pmb.helpers.frontend._parse_flavor(args, args.autoinstall)
+    if args.autoinstall:
+        pmb.chroot.initfs.build(args, flavor, "rootfs_" + args.device)
 
     # Check kernel config
     pmb.parse.kconfig.check(args, flavor)

pmb/helpers/frontend.py

@@ -46,13 +46,14 @@ import pmb.parse
 import pmb.qemu
 
 
-def _parse_flavor(args):
+def _parse_flavor(args, autoinstall=True):
     """
     Verify the flavor argument if specified, or return a default value.
+    :param autoinstall: make sure that at least one kernel flavor is installed
     """
     # Install at least one kernel and get installed flavors
     suffix = "rootfs_" + args.device
-    flavors = pmb.chroot.other.kernel_flavors_installed(args, suffix)
+    flavors = pmb.chroot.other.kernel_flavors_installed(args, suffix, autoinstall)
 
     # Parse and verify the flavor argument
     flavor = args.flavor

pmb/parse/arguments.py

@@ -50,6 +50,8 @@ def arguments_export(subparser):
                                     " (boot.img/kernel+initramfs only)",
                      action="store_true", dest="odin_flashable_tar")
     ret.add_argument("--flavor", default=None)
+    ret.add_argument("--no-install", dest="autoinstall", default=True,
+                     help="skip updating kernel/initfs", action="store_false")
     return ret
 
 
@@ -67,6 +69,8 @@ def arguments_flasher(subparser):
     flash_kernel = sub.add_parser("flash_kernel", help="flash a kernel")
     for action in [boot, flash_kernel]:
         action.add_argument("--flavor", default=None)
+        action.add_argument("--no-install", dest="autoinstall", default=True,
+                            help="skip updating kernel/initfs", action="store_false")
     flash_kernel.add_argument("--partition", default=None,
                               help="partition to flash the kernel to (defaults"
                                    " to deviceinfo_flash_*_partition_kernel)")