devtool: deploy: fix preservation of symlinks and permissions/ownership

It turns out that scp can't be used to copy symlinks because it follows
them instead of copying them, and this is by design (since it emulates
rcp which also behaved this way); the unfortunate result is that
symlinks that point to valid files on the host translate into the host
file being copied to the target (yuck).  The simplest alternative that
does not have this undesirable behaviour is to use tar and pipe it over
ssh.

At the same time, it would be even better if we properly reflect file
permissions and ownership on the target that have been established
within the pseudo environment. We can do this by executing the copy
process under pseudo, which turns out to be quite easy with access to
the pseudo environment set up by the build system.

Fixes [YOCTO #7868].

Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>

2 files changed, 23 insertions, 3 deletions

diff --git a/scripts/lib/devtool/__init__.py b/scripts/lib/devtool/__init__.py
index ea0b63e767..61b810c938 100644
--- a/scripts/lib/devtool/__init__.py
+++ b/scripts/lib/devtool/__init__.py
@@ -80,6 +80,22 @@ def exec_watch(cmd, **options):
 
     return buf, None
 
+def exec_fakeroot(d, cmd, **kwargs):
+    """Run a command under fakeroot (pseudo, in fact) so that it picks up the appropriate file permissions"""
+    # Grab the command and check it actually exists
+    fakerootcmd = d.getVar('FAKEROOTCMD', True)
+    if not os.path.exists(fakerootcmd):
+        logger.error('pseudo executable %s could not be found - have you run a build yet? pseudo-native should install this and if you have run any build then that should have been built')
+        return 2
+    # Set up the appropriate environment
+    newenv = dict(os.environ)
+    fakerootenv = d.getVar('FAKEROOTENV', True)
+    for varvalue in fakerootenv.split():
+        if '=' in varvalue:
+            splitval = varvalue.split('=', 1)
+            newenv[splitval[0]] = splitval[1]
+    return subprocess.call("%s %s" % (fakerootcmd, cmd), env=newenv, **kwargs)
+
 def setup_tinfoil():
     """Initialize tinfoil api from bitbake"""
     import scriptpath
diff --git a/scripts/lib/devtool/deploy.py b/scripts/lib/devtool/deploy.py
index ca74a8e51d..448db9637d 100644
--- a/scripts/lib/devtool/deploy.py
+++ b/scripts/lib/devtool/deploy.py
@@ -19,7 +19,7 @@
 import os
 import subprocess
 import logging
-from devtool import exec_build_env_command, setup_tinfoil, DevtoolError
+from devtool import exec_fakeroot, setup_tinfoil, DevtoolError
 
 logger = logging.getLogger('devtool')
 
@@ -73,9 +73,13 @@ def deploy(args, config, basepath, workspace):
     extraoptions = ''
     if args.no_host_check:
         extraoptions += '-o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no'
-    if not args.show_status:
+    if args.show_status:
+        tarextractopts = 'xv'
+    else:
+        tarextractopts = 'x'
         extraoptions += ' -q'
-    ret = subprocess.call('scp -r %s %s/* %s:%s' % (extraoptions, recipe_outdir, args.target, destdir), shell=True)
+    # We cannot use scp here, because it doesn't preserve symlinks
+    ret = exec_fakeroot(rd, 'tar cf - . | ssh %s %s \'tar %s -C %s -f -\'' % (extraoptions, args.target, tarextractopts, destdir), cwd=recipe_outdir, shell=True)
     if ret != 0:
         raise DevtoolError('Deploy failed - rerun with -s to get a complete '
                            'error message')