devtool: deploy-target: preserve existing files

If files would be overwritten by the deployment, preserve them in a
separate location on the target so that they can be restored if you
later run devtool undeploy-target.

At the same time, also check for sufficient space before starting the
operation so that we avoid potentially failing part way through.

Fixes [YOCTO #8978].

Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 78 insertions, 9 deletions

diff --git a/scripts/lib/devtool/deploy.py b/scripts/lib/devtool/deploy.py
index d54f6ba2e1..66644ccb6a 100644
--- a/scripts/lib/devtool/deploy.py
+++ b/scripts/lib/devtool/deploy.py
@@ -28,7 +28,7 @@ logger = logging.getLogger('devtool')
 
 deploylist_path = '/.devtool'
 
-def _prepare_remote_script(deploy, verbose=False, dryrun=False, undeployall=False):
+def _prepare_remote_script(deploy, verbose=False, dryrun=False, undeployall=False, nopreserve=False, nocheckspace=False):
     """
     Prepare a shell script for running on the target to
     deploy/undeploy files. We have to be careful what we put in this
@@ -48,6 +48,7 @@ def _prepare_remote_script(deploy, verbose=False, dryrun=False, undeployall=Fals
         if not deploy:
             lines.append('echo "Previously deployed files for $1:"')
     lines.append('manifest="%s/$1.list"' % deploylist_path)
+    lines.append('preservedir="%s/$1.preserve"' % deploylist_path)
     lines.append('if [ -f $manifest ] ; then')
     # Read manifest in reverse and delete files / remove empty dirs
     lines.append('    sed \'1!G;h;$!d\' $manifest | while read file')
@@ -58,7 +59,10 @@ def _prepare_remote_script(deploy, verbose=False, dryrun=False, undeployall=Fals
         lines.append('        fi')
     else:
         lines.append('        if [ -d $file ] ; then')
-        lines.append('            rmdir $file > /dev/null 2>&1 || true')
+        # Avoid deleting a preserved directory in case it has special perms
+        lines.append('            if [ ! -d $preservedir/$file ] ; then')
+        lines.append('                rmdir $file > /dev/null 2>&1 || true')
+        lines.append('            fi')
         lines.append('        else')
         lines.append('            rm $file')
         lines.append('        fi')
@@ -71,6 +75,39 @@ def _prepare_remote_script(deploy, verbose=False, dryrun=False, undeployall=Fals
     lines.append('fi')
 
     if deploy:
+        if not nocheckspace:
+            # Check for available space
+            # FIXME This doesn't take into account files spread across multiple
+            # partitions, but doing that is non-trivial
+            # Find the part of the destination path that exists
+            lines.append('checkpath="$2"')
+            lines.append('while [ "$checkpath" != "/" ] && [ ! -e $checkpath ]')
+            lines.append('do')
+            lines.append('    checkpath=`dirname "$checkpath"`')
+            lines.append('done')
+            lines.append('freespace=`df -P $checkpath | sed "1d" | awk \'{ print $4 }\'`')
+            # First line of the file is the total space
+            lines.append('total=`head -n1 $3`')
+            lines.append('if [ $total -gt $freespace ] ; then')
+            lines.append('    echo "ERROR: insufficient space on target (available ${freespace}, needed ${total})"')
+            lines.append('    exit 1')
+            lines.append('fi')
+        if not nopreserve:
+            # Preserve any files that exist. Note that this will add to the
+            # preserved list with successive deployments if the list of files
+            # deployed changes, but because we've deleted any previously
+            # deployed files at this point it will never preserve anything
+            # that was deployed, only files that existed prior to any deploying
+            # (which makes the most sense)
+            lines.append('cat $3 | sed "1d" | while read file fsize')
+            lines.append('do')
+            lines.append('    if [ -e $file ] ; then')
+            lines.append('    dest="$preservedir/$file"')
+            lines.append('    mkdir -p `dirname $dest`')
+            lines.append('    mv $file $dest')
+            lines.append('    fi')
+            lines.append('done')
+            lines.append('rm $3')
         lines.append('mkdir -p `dirname $manifest`')
         lines.append('mkdir -p $2')
         if verbose:
@@ -78,6 +115,14 @@ def _prepare_remote_script(deploy, verbose=False, dryrun=False, undeployall=Fals
         else:
             lines.append('    tar xv -C $2 -f - > $manifest')
         lines.append('sed -i "s!^./!$2!" $manifest')
+    elif not dryrun:
+        # Put any preserved files back
+        lines.append('if [ -d $preservedir ] ; then')
+        lines.append('    cd $preservedir')
+        lines.append('    find . -type f -exec mv {} /{} \;')
+        lines.append('    cd /')
+        lines.append('    rm -rf $preservedir')
+        lines.append('fi')
 
     if undeployall:
         if not dryrun:
@@ -94,6 +139,7 @@ def _prepare_remote_script(deploy, verbose=False, dryrun=False, undeployall=Fals
 def deploy(args, config, basepath, workspace):
     """Entry point for the devtool 'deploy' subcommand"""
     import re
+    import math
     import oe.recipeutils
 
     check_workspace_recipe(workspace, args.recipename, checksrc=False)
@@ -119,11 +165,23 @@ def deploy(args, config, basepath, workspace):
                            'recipe? If so, the install step has not installed '
                            'any files.' % args.recipename)
 
+    filelist = []
+    ftotalsize = 0
+    for root, _, files in os.walk(recipe_outdir):
+        for fn in files:
+            # Get the size in kiB (since we'll be comparing it to the output of du -k)
+            # MUST use lstat() here not stat() or getfilesize() since we don't want to
+            # dereference symlinks
+            fsize = int(math.ceil(float(os.lstat(os.path.join(root, fn)).st_size)/1024))
+            ftotalsize += fsize
+            # The path as it would appear on the target
+            fpath = os.path.join(destdir, os.path.relpath(root, recipe_outdir), fn)
+            filelist.append((fpath, fsize))
+
     if args.dry_run:
         print('Files to be deployed for %s on target %s:' % (args.recipename, args.target))
-        for root, _, files in os.walk(recipe_outdir):
-            for fn in files:
-                print('  %s' % os.path.join(destdir, os.path.relpath(root, recipe_outdir), fn))
+        for item, _ in filelist:
+            print('  %s' % item)
         return 0
 
 
@@ -140,11 +198,20 @@ def deploy(args, config, basepath, workspace):
     tmpdir = tempfile.mkdtemp(prefix='devtool')
     try:
         tmpscript = '/tmp/devtool_deploy.sh'
-        shellscript = _prepare_remote_script(deploy=True, verbose=args.show_status)
+        tmpfilelist = os.path.join(os.path.dirname(tmpscript), 'devtool_deploy.list')
+        shellscript = _prepare_remote_script(deploy=True,
+                                             verbose=args.show_status,
+                                             nopreserve=args.no_preserve,
+                                             nocheckspace=args.no_check_space)
         # Write out the script to a file
         with open(os.path.join(tmpdir, os.path.basename(tmpscript)), 'w') as f:
             f.write(shellscript)
-        # Copy it to the target
+        # Write out the file list
+        with open(os.path.join(tmpdir, os.path.basename(tmpfilelist)), 'w') as f:
+            f.write('%d\n' % ftotalsize)
+            for fpath, fsize in filelist:
+                f.write('%s %d\n' % (fpath, fsize))
+        # Copy them to the target
         ret = subprocess.call("scp %s %s/* %s:%s" % (extraoptions, tmpdir, args.target, os.path.dirname(tmpscript)), shell=True)
         if ret != 0:
             raise DevtoolError('Failed to copy script to %s - rerun with -s to '
@@ -153,7 +220,7 @@ def deploy(args, config, basepath, workspace):
         shutil.rmtree(tmpdir)
 
     # Now run the script
-    ret = exec_fakeroot(rd, 'tar cf - . | ssh %s %s \'sh %s %s %s\'' % (extraoptions, args.target, tmpscript, args.recipename, destdir), cwd=recipe_outdir, shell=True)
+    ret = exec_fakeroot(rd, 'tar cf - . | ssh %s %s \'sh %s %s %s %s\'' % (extraoptions, args.target, tmpscript, args.recipename, destdir, tmpfilelist), cwd=recipe_outdir, shell=True)
     if ret != 0:
         raise DevtoolError('Deploy failed - rerun with -s to get a complete '
                            'error message')
@@ -213,13 +280,15 @@ def register_commands(subparsers, context):
     """Register devtool subcommands from the deploy plugin"""
     parser_deploy = subparsers.add_parser('deploy-target',
                                           help='Deploy recipe output files to live target machine',
-                                          description='Deploys a recipe\'s build output (i.e. the output of the do_install task) to a live target machine over ssh. Note: this only deploys the recipe itself and not any runtime dependencies, so it is assumed that those have been installed on the target beforehand.',
+                                          description='Deploys a recipe\'s build output (i.e. the output of the do_install task) to a live target machine over ssh. By default, any existing files will be preserved instead of being overwritten and will be restored if you run devtool undeploy-target. Note: this only deploys the recipe itself and not any runtime dependencies, so it is assumed that those have been installed on the target beforehand.',
                                           group='testbuild')
     parser_deploy.add_argument('recipename', help='Recipe to deploy')
     parser_deploy.add_argument('target', help='Live target machine running an ssh server: user@hostname[:destdir]')
     parser_deploy.add_argument('-c', '--no-host-check', help='Disable ssh host key checking', action='store_true')
     parser_deploy.add_argument('-s', '--show-status', help='Show progress/status output', action='store_true')
     parser_deploy.add_argument('-n', '--dry-run', help='List files to be deployed only', action='store_true')
+    parser_deploy.add_argument('-p', '--no-preserve', help='Do not preserve existing files', action='store_true')
+    parser_deploy.add_argument('--no-check-space', help='Do not check for available space before deploying', action='store_true')
     parser_deploy.set_defaults(func=deploy)
 
     parser_undeploy = subparsers.add_parser('undeploy-target',