lib/repo: Support hardlink conversions from bare-user to bu-only

Thinking about the problem of flatpak converting from `bare-user` to `bare-user-only`
"in place" by creating a new repo and doing a `pull-local`, I realized
that we can optimize this process by doing hardlinks for both metadata
and regular files.  The repo formats are *almost* compatible, the
exception being symlinks.

An earlier patch caused us to do hardlinks for metadata, this patch takes things
to the next step and special cases this specific conversion. In this case we
need to parse the source object to determine whether or not it's a symlink.

Closes: #922
Approved by: alexlarsson

1 files changed, 23 insertions, 7 deletions

diff --git a/tests/libtest.sh b/tests/libtest.sh
index 1774a7b6..15802dfd 100755
--- a/tests/libtest.sh
+++ b/tests/libtest.sh
@@ -116,10 +116,16 @@ else
     fi
 fi
 
+files_are_hardlinked() {
+    f1=$(stat -c %i $1)
+    f2=$(stat -c %i $2)
+    [ "$f1" == "$f2" ]
+}
+
 assert_files_hardlinked() {
     f1=$(stat -c %i $1)
     f2=$(stat -c %i $2)
-    if [ "$f1" != "$f2" ]; then
+    if ! files_are_hardlinked "$f1" "$f2"; then
         fatal "Files '$1' and '$2' are not hardlinked"
     fi
 }
@@ -512,12 +518,22 @@ ostree_file_path_to_checksum() {
     $CMD_PREFIX ostree --repo=$repo ls -C $ref $path | awk '{ print $5 }'
 }
 
+# Given a path to a file in a repo for a ref, print the (relative) path to its
+# object
+ostree_file_path_to_relative_object_path() {
+    repo=$1
+    ref=$2
+    path=$3
+    checksum=$(ostree_file_path_to_checksum $repo $ref $path)
+    test -n "${checksum}"
+    echo objects/${checksum:0:2}/${checksum:2}.file
+}
+
 # Given a path to a file in a repo for a ref, print the path to its object
 ostree_file_path_to_object_path() {
-   repo=$1
-   ref=$2
-   path=$3
-   checksum=$(ostree_file_path_to_checksum $repo $ref $path)
-   test -n "${checksum}"
-   echo ${repo}/objects/${checksum:0:2}/${checksum:2}.file
+    repo=$1
+    ref=$2
+    path=$3
+    relpath=$(ostree_file_path_to_relative_object_path $repo $ref $path)
+    echo ${repo}/${relpath}
 }