Allow creating and pulling static deltas starting from "empty"

You create these with something like:
  ostree static-delta generate --empty --to=master

These will be automatically used during pull if no previous revision
exists in the target repo.

These work very much like the normal static deltas except they
are named just by the "to" revision. I.e:

deltas/94/f7d2dc23759dd21f9bd01e6705a8fdf98f90cad3e0109ba3f6c091c1a3774d

for a from-scratch to 94f7d2dc23759dd21f9bd01e6705a8fdf98f90cad3e0109ba3f6c091c1a3774d delta.

https://bugzilla.gnome.org/show_bug.cgi?id=721799

diff --git a/src/libostree/ostree-core.c b/src/libostree/ostree-core.c
index 87f29108a15bacbc5e9444311fede88d8b220c10..2d70e226b22d1a38cc835dc55f9907f48b7ceffb 100644 (file)
--- a/src/libostree/ostree-core.c
+++ b/src/libostree/ostree-core.c
@@ -1348,11 +1348,22 @@ get_delta_path (const char *from,
                 const char *target)
 {
   char prefix[3];
-  prefix[0] = from[0];
-  prefix[1] = from[1];
-  prefix[2] = '\0';
-  from += 2;
-  return g_strconcat ("deltas/", prefix, "/", from, "-", to, "/", target, NULL);
+  if (from == NULL)
+    {
+      prefix[0] = to[0];
+      prefix[1] = to[1];
+      prefix[2] = '\0';
+      to += 2;
+      return g_strconcat ("deltas/", prefix, "/", to, "/", target, NULL);
+    }
+  else
+    {
+      prefix[0] = from[0];
+      prefix[1] = from[1];
+      prefix[2] = '\0';
+      from += 2;
+      return g_strconcat ("deltas/", prefix, "/", from, "-", to, "/", target, NULL);
+    }
 }
 
 char *

diff --git a/src/libostree/ostree-diff.c b/src/libostree/ostree-diff.c
index 6749b654fcb3a8eca4a46e05a512e05fa125acb6..150d33456a5807ee54549b37337801ecbc5ade81 100644 (file)
--- a/src/libostree/ostree-diff.c
+++ b/src/libostree/ostree-diff.c
@@ -204,7 +204,7 @@ diff_add_dir_recurse (GFile          *d,
 /**
  * ostree_diff_dirs:
  * @flags: Flags
- * @a: First directory path
+ * @a: First directory path, or %NULL
  * @b: First directory path
  * @modified: (element-type OstreeDiffItem): Modified files
  * @removed: (element-type Gio.File): Removed files
@@ -231,6 +231,15 @@ ostree_diff_dirs (OstreeDiffFlags flags,
   gs_unref_object GFileInfo *child_a_info = NULL;
   gs_unref_object GFileInfo *child_b_info = NULL;
 
+  if (a == NULL)
+    {
+      if (!diff_add_dir_recurse (b, added, cancellable, error))
+        goto out;
+
+      ret = TRUE;
+      goto out;
+    }
+
   child_a_info = g_file_query_info (a, OSTREE_GIO_FAST_QUERYINFO,
                                     G_FILE_QUERY_INFO_NOFOLLOW_SYMLINKS,
                                     cancellable, error);

diff --git a/src/libostree/ostree-repo-pull.c b/src/libostree/ostree-repo-pull.c
index f3b8253a0bb336e7d40a31f81b68f9c02b81e970..2cd40a3b34998822548bb931686e1bd268884a06 100644 (file)
--- a/src/libostree/ostree-repo-pull.c
+++ b/src/libostree/ostree-repo-pull.c
@@ -1446,7 +1446,7 @@ process_one_static_delta (OtPullData   *pull_data,
       if (have_all)
         {
           g_debug ("Have all objects from static delta %s-%s part %u",
-                   from_revision, to_revision,
+                   from_revision ? from_revision : "empty", to_revision,
                    i);
           continue;
         }
@@ -1912,7 +1912,7 @@ ostree_repo_pull_with_options (OstreeRepo             *self,
                                     &from_revision, error))
         goto out;
 
-      if (from_revision && g_strcmp0 (from_revision, to_revision) != 0)
+      if (from_revision == NULL || g_strcmp0 (from_revision, to_revision) != 0)
         {
           if (!request_static_delta_superblock_sync (pull_data, from_revision, to_revision,
                                                      &delta_superblock, cancellable, error))
@@ -1921,14 +1921,14 @@ ostree_repo_pull_with_options (OstreeRepo             *self,
           
       if (!delta_superblock)
         {
-          g_debug ("no delta superblock for %s-%s", from_revision, to_revision);
+          g_debug ("no delta superblock for %s-%s", from_revision ? from_revision : "empty", to_revision);
           if (!scan_one_metadata_object (pull_data, to_revision, OSTREE_OBJECT_TYPE_COMMIT,
                                          0, pull_data->cancellable, error))
             goto out;
         }
       else
         {
-          g_debug ("processing delta superblock for %s-%s", from_revision, to_revision);
+          g_debug ("processing delta superblock for %s-%s", from_revision ? from_revision : "empty", to_revision);
           if (!process_one_static_delta (pull_data, from_revision, to_revision,
                                          delta_superblock,
                                          cancellable, error))

diff --git a/src/libostree/ostree-repo-static-delta-compilation.c b/src/libostree/ostree-repo-static-delta-compilation.c
index 5aca367e9cd8ec6a63f5e463c19d3d10f80ba593..5f08215600d262aa0a7803087806de2b74934ed1 100644 (file)
--- a/src/libostree/ostree-repo-static-delta-compilation.c
+++ b/src/libostree/ostree-repo-static-delta-compilation.c
@@ -203,9 +203,12 @@ generate_delta_lowlatency (OstreeRepo                       *repo,
   gs_unref_hashtable GHashTable *modified_content_objects = NULL;
   gs_unref_hashtable GHashTable *content_object_to_size = NULL;
 
-  if (!ostree_repo_read_commit (repo, from, &root_from, NULL,
-                                cancellable, error))
-    goto out;
+  if (from != NULL)
+    {
+      if (!ostree_repo_read_commit (repo, from, &root_from, NULL,
+                                    cancellable, error))
+        goto out;
+    }
   if (!ostree_repo_read_commit (repo, to, &root_to, NULL,
                                 cancellable, error))
     goto out;
@@ -231,9 +234,12 @@ generate_delta_lowlatency (OstreeRepo                       *repo,
       g_hash_table_add (modified_content_objects, objname);
     }
 
-  if (!ostree_repo_traverse_commit (repo, from, 0, &from_reachable_objects,
-                                    cancellable, error))
-    goto out;
+  if (from)
+    {
+      if (!ostree_repo_traverse_commit (repo, from, 0, &from_reachable_objects,
+                                        cancellable, error))
+        goto out;
+    }
 
   if (!ostree_repo_traverse_commit (repo, to, 0, &to_reachable_objects,
                                     cancellable, error))
@@ -249,7 +255,7 @@ generate_delta_lowlatency (OstreeRepo                       *repo,
       const char *checksum;
       OstreeObjectType objtype;
 
-      if (g_hash_table_contains (from_reachable_objects, serialized_key))
+      if (from_reachable_objects && g_hash_table_contains (from_reachable_objects, serialized_key))
         continue;
 
       ostree_object_name_deserialize (serialized_key, &checksum, &objtype);
@@ -412,17 +418,17 @@ get_fallback_headers (OstreeRepo               *self,
  * ostree_repo_static_delta_generate:
  * @self: Repo
  * @opt: High level optimization choice
- * @from: ASCII SHA256 checksum of origin
+ * @from: ASCII SHA256 checksum of origin, or %NULL
  * @to: ASCII SHA256 checksum of target
  * @metadata: (allow-none): Optional metadata
  * @params: (allow-none): Parameters, see below
  * @cancellable: Cancellable
  * @error: Error
  *
- * Generate a lookaside "static delta" from @from which can generate
- * the objects in @to.  This delta is an optimization over fetching
- * individual objects, and can be conveniently stored and applied
- * offline.
+ * Generate a lookaside "static delta" from @from (%NULL means
+ * from-empty) which can generate the objects in @to.  This delta is
+ * an optimization over fetching individual objects, and can be
+ * conveniently stored and applied offline.
  *
  * The @params argument should be an a{sv}.  The following attributes
  * are known:
@@ -590,9 +596,10 @@ ostree_repo_static_delta_generate (OstreeRepo                   *self,
   {
     GDateTime *now = g_date_time_new_now_utc ();
     /* floating */ GVariant *from_csum_v =
-      ostree_checksum_to_bytes_v (from);
+      from ? ostree_checksum_to_bytes_v (from) : ot_gvariant_new_bytearray ((guchar *)"", 0);
     /* floating */ GVariant *to_csum_v =
       ostree_checksum_to_bytes_v (to);
+
     delta_descriptor = g_variant_new ("(@(a(ss)a(say))t@ay@ay@" OSTREE_COMMIT_GVARIANT_STRING "ay"
                                       "a" OSTREE_STATIC_DELTA_META_ENTRY_FORMAT
                                       "@a" OSTREE_STATIC_DELTA_FALLBACK_FORMAT ")",

diff --git a/src/libostree/ostree-repo.c b/src/libostree/ostree-repo.c
index 4d93a89b2c4976c0af7aa5ee68c458207800df29..22abe91423ba9233c7cf44e61042862b85d7b2f2 100644 (file)
--- a/src/libostree/ostree-repo.c
+++ b/src/libostree/ostree-repo.c
@@ -3069,7 +3069,7 @@ out:
 /**
  * ostree_repo_sign_delta:
  * @self: Self
- * @from_commit: SHA256 of starting commit to sign
+ * @from_commit: SHA256 of starting commit to sign, or %NULL
  * @to_commit: SHA256 of target commit to sign
  * @key_id: Use this GPG key id
  * @homedir: (allow-none): GPG home directory, or %NULL

diff --git a/src/ostree/ot-builtin-static-delta.c b/src/ostree/ot-builtin-static-delta.c
index b133c4c33e13b23d02e320a34e26a19fd4d14641..45ba6b67e425a1a739f7d47974855c378b6a81ae 100644 (file)
--- a/src/ostree/ot-builtin-static-delta.c
+++ b/src/ostree/ot-builtin-static-delta.c
@@ -31,6 +31,7 @@ static char *opt_to_rev;
 static char **opt_key_ids;
 static char *opt_gpg_homedir;
 static char *opt_max_usize;
+static gboolean opt_empty;
 
 #define BUILTINPROTO(name) static gboolean ot_static_delta_builtin_ ## name (int argc, char **argv, GCancellable *cancellable, GError **error)
 
@@ -50,6 +51,7 @@ static OstreeCommand static_delta_subcommands[] = {
 
 static GOptionEntry generate_options[] = {
   { "from", 0, 0, G_OPTION_ARG_STRING, &opt_from_rev, "Create delta from revision REV", "REV" },
+  { "empty", 0, 0, G_OPTION_ARG_NONE, &opt_empty, "Create delta from scratch", NULL },
   { "to", 0, 0, G_OPTION_ARG_STRING, &opt_to_rev, "Create delta to revision REV", "REV" },
   { "gpg-sign", 0, 0, G_OPTION_ARG_STRING_ARRAY, &opt_key_ids, "GPG Key ID to sign the delta with", "key-id"},
   { "gpg-homedir", 0, 0, G_OPTION_ARG_STRING, &opt_gpg_homedir, "GPG Homedir to use when looking for keyrings", "homedir"},
@@ -153,7 +155,11 @@ ot_static_delta_builtin_generate (int argc, char **argv, GCancellable *cancellab
 
       g_assert (opt_to_rev);
 
-      if (opt_from_rev == NULL)
+      if (opt_empty)
+        {
+          from_source = NULL;
+        }
+      else if (opt_from_rev == NULL)
         {
           from_parent_str = g_strconcat (opt_to_rev, "^", NULL);
           from_source = from_parent_str;
@@ -163,8 +169,11 @@ ot_static_delta_builtin_generate (int argc, char **argv, GCancellable *cancellab
           from_source = opt_from_rev;
         }
 
-      if (!ostree_repo_resolve_rev (repo, from_source, FALSE, &from_resolved, error))
-        goto out;
+      if (from_source)
+        {
+          if (!ostree_repo_resolve_rev (repo, from_source, FALSE, &from_resolved, error))
+            goto out;
+        }
       if (!ostree_repo_resolve_rev (repo, opt_to_rev, FALSE, &to_resolved, error))
         goto out;
 
@@ -174,7 +183,7 @@ ot_static_delta_builtin_generate (int argc, char **argv, GCancellable *cancellab
                                "max-usize", g_variant_new_uint32 (g_ascii_strtoull (opt_max_usize, NULL, 10)));
 
       g_print ("Generating static delta:\n");
-      g_print ("  From: %s\n", from_resolved);
+      g_print ("  From: %s\n", from_resolved ? from_resolved : "empty");
       g_print ("  To:   %s\n", to_resolved);
       if (!ostree_repo_static_delta_generate (repo, OSTREE_STATIC_DELTA_GENERATE_OPT_MAJOR,
                                               from_resolved, to_resolved, NULL,

diff --git a/tests/test-delta.sh b/tests/test-delta.sh
index 175daec202845699cc6ba809667e01a830692d04..c598186126f53183e6ca2b6c396ca7a3cf408ebe 100755 (executable)
--- a/tests/test-delta.sh
+++ b/tests/test-delta.sh
@@ -55,17 +55,23 @@ function permuteDirectory() {
     done
 }
 
+origrev=$(ostree --repo=repo rev-parse test)
+
+ostree --repo=repo static-delta generate --empty --to=${origrev}
+ostree --repo=repo static-delta list | grep ${origrev} || exit 1
+
 permuteDirectory 1 files
 ostree --repo=repo commit -b test -s test --tree=dir=files
-ostree --repo=repo static-delta list
 
-origrev=$(ostree --repo=repo rev-parse test^)
 newrev=$(ostree --repo=repo rev-parse test)
 ostree --repo=repo static-delta generate --from=${origrev} --to=${newrev}
 
+ostree --repo=repo static-delta list | grep ${origrev}-${newrev} || exit 1
+
 origstart=$(echo ${origrev} | dd bs=1 count=2 2>/dev/null)
 origend=$(echo ${origrev} | dd bs=1 skip=2 2>/dev/null)
 assert_has_dir repo/deltas/${origstart}/${origend}-${newrev}
+assert_has_dir repo/deltas/${origstart}/${origend}
 
 mkdir repo2
 ostree --repo=repo2 init --mode=archive-z2
@@ -74,3 +80,9 @@ ostree --repo=repo2 pull-local repo ${origrev}
 ostree --repo=repo2 static-delta apply-offline repo/deltas/${origstart}/${origend}-${newrev}
 ostree --repo=repo2 fsck
 ostree --repo=repo2 show ${newrev}
+
+mkdir repo3
+ostree --repo=repo3 init --mode=archive-z2
+ostree --repo=repo3 static-delta apply-offline repo/deltas/${origstart}/${origend}
+ostree --repo=repo3 fsck
+ostree --repo=repo3 show ${origrev}