commit: lookup payload-link in the parent repository

Move all the logic for the payload-lookup to a new function
"_lookup_payload_link" and enable the lookup for the payload also in the
parent repository when it is present.

Signed-off-by: Giuseppe Scrivano <[email protected]>

src/libostree/ostree-repo-commit.c

@@ -614,6 +614,63 @@ _create_payload_link (OstreeRepo   *self,
   return TRUE;
 }
 
+static gboolean
+_lookup_payload_link (OstreeRepo   *self,
+                      const char   *actual_payload_checksum,
+                      GFileInfo    *file_info,
+                      GLnxTmpfile  *tmpf,
+                      GCancellable *cancellable,
+                      GError       **error)
+{
+  int dfd_searches[] = { -1, self->objects_dir_fd };
+  if (self->commit_stagedir.initialized)
+    dfd_searches[0] = self->commit_stagedir.fd;
+  for (guint i = 0; i < G_N_ELEMENTS (dfd_searches); i++)
+    {
+      glnx_autofd int fdf = -1;
+      char loose_path_buf[_OSTREE_LOOSE_PATH_MAX];
+      char loose_path_target_buf[_OSTREE_LOOSE_PATH_MAX];
+      char target_checksum[OSTREE_SHA256_STRING_LEN+1];
+      int dfd = dfd_searches[i];
+      if (dfd == -1)
+        continue;
+
+      _ostree_loose_path (loose_path_buf, actual_payload_checksum, OSTREE_OBJECT_TYPE_PAYLOAD_LINK, self->mode);
+
+      if (TEMP_FAILURE_RETRY (readlinkat (dfd, loose_path_buf, target_checksum, sizeof (target_checksum))) < 0)
+        {
+          if (errno == ENOENT)
+            continue;
+          return glnx_throw_errno (error);
+        }
+
+      _ostree_loose_path (loose_path_target_buf, target_checksum, OSTREE_OBJECT_TYPE_FILE, self->mode);
+      if (!ot_openat_ignore_enoent (dfd, loose_path_target_buf, &fdf, error))
+        return FALSE;
+
+      if (fdf < 0)
+        {
+          /* If the link is referring to an object that doesn't exist anymore in the repository, just unlink it.  */
+          if (!glnx_unlinkat (dfd, loose_path_buf, 0, error))
+            return FALSE;
+        }
+      else
+        {
+          if (ftruncate (tmpf->fd, 0) < 0)
+            return glnx_throw_errno (error);
+
+          if (glnx_regfile_copy_bytes (fdf, tmpf->fd, -1) < 0)
+            return glnx_throw_errno_prefix (error, "regfile copy");
+
+          return TRUE;
+        }
+    }
+  if (self->parent_repo)
+    return _lookup_payload_link (self->parent_repo, actual_payload_checksum, file_info, tmpf, cancellable, error);
+
+  return TRUE;
+}
+
 /* The main driver for writing a content (regfile or symlink) object.
  * There are a variety of tricky cases here; for example, bare-user
  * repos store symlinks as regular files.  Computing checksums
@@ -894,52 +951,8 @@ write_content_object (OstreeRepo         *self,
           repo_store_size_entry (self, actual_checksum, unpacked_size, stbuf.st_size);
         }
 
-      if (actual_payload_checksum)
-        {
-          int dfd_searches[] = { -1, self->objects_dir_fd };
-          if (self->commit_stagedir.initialized)
-            dfd_searches[0] = self->commit_stagedir.fd;
-          for (guint i = 0; i < G_N_ELEMENTS (dfd_searches); i++)
-            {
-              glnx_autofd int fdf = -1;
-              char loose_path_buf[_OSTREE_LOOSE_PATH_MAX];
-              char loose_path_target_buf[_OSTREE_LOOSE_PATH_MAX];
-              char target_checksum[OSTREE_SHA256_STRING_LEN+1];
-              int dfd = dfd_searches[i];
-              if (dfd == -1)
-                continue;
-
-              _ostree_loose_path (loose_path_buf, actual_payload_checksum, OSTREE_OBJECT_TYPE_PAYLOAD_LINK, self->mode);
-
-              if (readlinkat (dfd, loose_path_buf, target_checksum, sizeof (target_checksum)) < 0)
-                {
-                  if (errno == ENOENT)
-                    continue;
-                  return glnx_throw_errno (error);
-                }
-
-              _ostree_loose_path (loose_path_target_buf, target_checksum, OSTREE_OBJECT_TYPE_FILE, self->mode);
-              if (!ot_openat_ignore_enoent (dfd, loose_path_target_buf, &fdf, error))
-                return FALSE;
-
-              if (fdf < 0)
-                {
-                  /* If the link is referring to an object that doesn't exist anymore in the repository, just unlink it.  */
-                  if (!glnx_unlinkat (dfd, loose_path_buf, 0, error))
-                    return FALSE;
-                }
-              else
-                {
-                  if (ftruncate (tmpf.fd, 0) < 0)
-                    return glnx_throw_errno (error);
-
-                  if (glnx_regfile_copy_bytes (fdf, tmpf.fd, -1) < 0)
-                    return glnx_throw_errno_prefix (error, "regfile copy");
-
-                  return TRUE;
-                }
-            }
-        }
+      if (actual_payload_checksum && !_lookup_payload_link (self, actual_payload_checksum, file_info, &tmpf, cancellable, error))
+        return FALSE;
 
       /* This path is for regular files */
       if (!commit_loose_regfile_object (self, actual_checksum, &tmpf,