Author: stefan2
Date: Sat Jan 4 00:28:16 2014
New Revision: 1555297
URL: http://svn.apache.org/r1555297
Log:
Extend the get_file_delta_stream optimization to self-deltas.
Dump code will request self-deltas (delta against a NULL source)
for newly added files. FSFS will often use the same representation
on disk.
* subversion/libsvn_fs_fs/cached_data.c
(get_storaged_delta_stream): New utility function factored out from ...
(svn_fs_fs__get_file_delta_stream): ... this. Add another special case
if a self-delta has been requested.
Modified:
subversion/trunk/subversion/libsvn_fs_fs/cached_data.c
Modified: subversion/trunk/subversion/libsvn_fs_fs/cached_data.c
URL:
http://svn.apache.org/viewvc/subversion/trunk/subversion/libsvn_fs_fs/cached_data.c?rev=1555297&r1=1555296&r2=1555297&view=diff
==============================================================================
--- subversion/trunk/subversion/libsvn_fs_fs/cached_data.c (original)
+++ subversion/trunk/subversion/libsvn_fs_fs/cached_data.c Sat Jan 4 00:28:16
2014
@@ -1830,6 +1830,23 @@ delta_read_md5_digest(void *baton)
return drb->md5_digest;
}
+/* Return a txdelta stream for on-disk representation REP_STATE
+ * of TARGET. Allocate the result in POOL.
+ */
+static svn_txdelta_stream_t *
+get_storaged_delta_stream(rep_state_t *rep_state,
+ node_revision_t *target,
+ apr_pool_t *pool)
+{
+ /* Create the delta read baton. */
+ struct delta_read_baton *drb = apr_pcalloc(pool, sizeof(*drb));
+ drb->rs = rep_state;
+ memcpy(drb->md5_digest, target->data_rep->md5_digest,
+ sizeof(drb->md5_digest));
+ return svn_txdelta_stream_create(drb, delta_read_next_window,
+ delta_read_md5_digest, pool);
+}
+
svn_error_t *
svn_fs_fs__get_file_delta_stream(svn_txdelta_stream_t **stream_p,
svn_fs_t *fs,
@@ -1838,41 +1855,46 @@ svn_fs_fs__get_file_delta_stream(svn_txd
apr_pool_t *pool)
{
svn_stream_t *source_stream, *target_stream;
+ rep_state_t *rep_state;
+ svn_fs_fs__rep_header_t *rep_header;
+
+ /* Read target's base rep if any. */
+ SVN_ERR(create_rep_state(&rep_state, &rep_header, NULL,
+ target->data_rep, fs, pool));
/* Try a shortcut: if the target is stored as a delta against the source,
then just use that delta. */
if (source && source->data_rep && target->data_rep)
{
- rep_state_t *rep_state;
- svn_fs_fs__rep_header_t *rep_header;
-
- /* Read target's base rep if any. */
- SVN_ERR(create_rep_state(&rep_state, &rep_header, NULL,
- target->data_rep, fs, pool));
-
/* If that matches source, then use this delta as is.
Note that we want an actual delta here. E.g. a self-delta would
- not be good enogh. */
+ not be good enough. */
if (rep_header->type == svn_fs_fs__rep_delta
&& rep_header->base_revision == source->data_rep->revision
&& rep_header->base_item_index == source->data_rep->item_index)
{
- /* Create the delta read baton. */
- struct delta_read_baton *drb = apr_pcalloc(pool, sizeof(*drb));
- drb->rs = rep_state;
- memcpy(drb->md5_digest, target->data_rep->md5_digest,
- sizeof(drb->md5_digest));
- *stream_p = svn_txdelta_stream_create(drb, delta_read_next_window,
- delta_read_md5_digest, pool);
+ *stream_p = get_storaged_delta_stream(rep_state, target, pool);
return SVN_NO_ERROR;
}
- else if (rep_state->sfile->rfile)
+ }
+ else if (!source)
+ {
+ /* We want a self-delta. There is a fair chance that TARGET got added
+ in this revision and is already stored in the requested format. */
+ if (rep_header->type == svn_fs_fs__rep_self_delta)
{
- SVN_ERR(svn_fs_fs__close_revision_file(rep_state->sfile->rfile));
- rep_state->sfile->rfile = NULL;
+ *stream_p = get_storaged_delta_stream(rep_state, target, pool);
+ return SVN_NO_ERROR;
}
}
+ /* Don't keep file handles open for longer than necessary. */
+ if (rep_state->sfile->rfile)
+ {
+ SVN_ERR(svn_fs_fs__close_revision_file(rep_state->sfile->rfile));
+ rep_state->sfile->rfile = NULL;
+ }
+
/* Read both fulltexts and construct a delta. */
if (source)
SVN_ERR(svn_fs_fs__get_contents(&source_stream, fs, source->data_rep,
