[gnome-continuous-yocto/gnomeostree-3.28-rocko: 4643/8267] wic: Add --exclude-path option to rootfs source plugin.

[Emmanuele Bassi <ebassi src gnome org>]

commit f6a064d969f4149b2152ed2e851828acaaec07ca
Author: Kristian Amlie <kristian amlie mender io>
Date:   Mon Feb 6 17:16:46 2017 +0100

    wic: Add --exclude-path option to rootfs source plugin.
    
    It will omit the given path from the resulting partition, and if the
    given path ends in a slash, it will only delete the content, and keep
    the directory.
    
    Since mkfs only accepts whole directories as input, we need to copy
    the rootfs directory to the workdir so that we can selectively delete
    files from it.
    
    Since we want to use the copyhardlinktree() function, we need to put
    the generic oe lib in the module search path.
    
    (From OE-Core rev: 6602392db3d391d926dead49fcc54326015cfe35)
    
    Signed-off-by: Kristian Amlie <kristian amlie mender io>
    Signed-off-by: Ross Burton <ross burton intel com>
    Signed-off-by: Richard Purdie <richard purdie linuxfoundation org>

 scripts/lib/wic/help.py                  |    6 ++++
 scripts/lib/wic/ksparser.py              |    1 +
 scripts/lib/wic/partition.py             |    1 +
 scripts/lib/wic/plugins/source/rootfs.py |   43 +++++++++++++++++++++++++++++-
 scripts/wic                              |    2 +
 5 files changed, 52 insertions(+), 1 deletions(-)
---
diff --git a/scripts/lib/wic/help.py b/scripts/lib/wic/help.py
index 1bd411d..63bbc23 100644
--- a/scripts/lib/wic/help.py
+++ b/scripts/lib/wic/help.py
@@ -721,6 +721,12 @@ DESCRIPTION
                      partition table. It may be useful for
                      bootloaders.
 
+         --exclude-path: This option is specific to wic. It excludes the given
+                         absolute path from the resulting image. If the path
+                         ends with a slash, only the content of the directory
+                         is omitted, not the directory itself. This option only
+                         has an effect with the rootfs source plugin.
+
          --extra-space: This option is specific to wic. It adds extra
                         space after the space filled by the content
                         of the partition. The final size can go
diff --git a/scripts/lib/wic/ksparser.py b/scripts/lib/wic/ksparser.py
index 41d3cc6..f0aa5d0 100644
--- a/scripts/lib/wic/ksparser.py
+++ b/scripts/lib/wic/ksparser.py
@@ -130,6 +130,7 @@ class KickStart():
         part.add_argument('mountpoint', nargs='?')
         part.add_argument('--active', action='store_true')
         part.add_argument('--align', type=int)
+        part.add_argument('--exclude-path', nargs='+')
         part.add_argument("--extra-space", type=sizetype)
         part.add_argument('--fsoptions', dest='fsopts')
         part.add_argument('--fstype')
diff --git a/scripts/lib/wic/partition.py b/scripts/lib/wic/partition.py
index 754ad75..1221f69 100644
--- a/scripts/lib/wic/partition.py
+++ b/scripts/lib/wic/partition.py
@@ -40,6 +40,7 @@ class Partition():
         self.disk = args.disk
         self.device = None
         self.extra_space = args.extra_space
+        self.exclude_path = args.exclude_path
         self.fsopts = args.fsopts
         self.fstype = args.fstype
         self.label = args.label
diff --git a/scripts/lib/wic/plugins/source/rootfs.py b/scripts/lib/wic/plugins/source/rootfs.py
index 9d959fa..c57a434 100644
--- a/scripts/lib/wic/plugins/source/rootfs.py
+++ b/scripts/lib/wic/plugins/source/rootfs.py
@@ -26,10 +26,13 @@
 #
 
 import os
+import shutil
+
+from oe.path import copyhardlinktree
 
 from wic import msger
 from wic.pluginbase import SourcePlugin
-from wic.utils.misc import get_bitbake_var
+from wic.utils.misc import get_bitbake_var, exec_cmd
 
 class RootfsPlugin(SourcePlugin):
     """
@@ -78,6 +81,44 @@ class RootfsPlugin(SourcePlugin):
 
         real_rootfs_dir = cls.__get_rootfs_dir(rootfs_dir)
 
+        # Handle excluded paths.
+        if part.exclude_path is not None:
+            # We need a new rootfs directory we can delete files from. Copy to
+            # workdir.
+            new_rootfs = os.path.realpath(os.path.join(cr_workdir, "rootfs"))
+
+            if os.path.lexists(new_rootfs):
+                shutil.rmtree(os.path.join(new_rootfs))
+
+            copyhardlinktree(real_rootfs_dir, new_rootfs)
+
+            real_rootfs_dir = new_rootfs
+
+            for orig_path in part.exclude_path:
+                path = orig_path
+                if os.path.isabs(path):
+                    msger.error("Must be relative: --exclude-path=%s" % orig_path)
+
+                full_path = os.path.realpath(os.path.join(new_rootfs, path))
+
+                # Disallow climbing outside of parent directory using '..',
+                # because doing so could be quite disastrous (we will delete the
+                # directory).
+                if not full_path.startswith(new_rootfs):
+                    msger.error("'%s' points to a path outside the rootfs" % orig_path)
+
+                if path.endswith(os.sep):
+                    # Delete content only.
+                    for entry in os.listdir(full_path):
+                        full_entry = os.path.join(full_path, entry)
+                        if os.path.isdir(full_entry) and not os.path.islink(full_entry):
+                            shutil.rmtree(full_entry)
+                        else:
+                            os.remove(full_entry)
+                else:
+                    # Delete whole directory.
+                    shutil.rmtree(full_path)
+
         part.rootfs_dir = real_rootfs_dir
         part.prepare_rootfs(cr_workdir, oe_builddir,
                             real_rootfs_dir, native_sysroot)
diff --git a/scripts/wic b/scripts/wic
index 1b7d7df..10a03ee 100755
--- a/scripts/wic
+++ b/scripts/wic
@@ -41,6 +41,8 @@ from distutils import spawn
 scripts_path = os.path.abspath(os.path.dirname(__file__))
 lib_path = scripts_path + '/lib'
 sys.path.insert(0, lib_path)
+oe_lib_path = os.path.join(os.path.dirname(scripts_path), 'meta', 'lib')
+sys.path.insert(0, oe_lib_path)
 
 bitbake_exe = spawn.find_executable('bitbake')
 if bitbake_exe: