Rely on fast-import for information about previous revs.
This requires always setting up backward flow of information, even for
v2 dumps. On the plus side, it simplifies the code by quite a bit and
opens the door to further simplifications.
[db: adjusted to support final version of the cat-blob patch]
[jn: avoiding hard-coding git's name for the empty tree for
portability to other backends]
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: David Barr <david.barr@cordelta.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Current svn-fe produces output like this:
blob
mark :7382321
data 5
hello
blob
mark :7382322
data 5
Hello
commit
mark :3
[...]
M 100644 :7382321 hello.c
M 100644 :7382322 hello2.c
This means svn-fe has to keep track of the paths modified in each
commit and the corresponding marks, instead of dealing with each file
as it arrives in input and then forgetting about it. A better
strategy would be to use inline blobs:
commit
mark :3
[...]
M 100644 inline hello.c
data 5
hello
[...]
As a first step towards that, teach svn-fe to notice when the
collection of blobs for each commit starts and write a comment
("# commit 3.") there.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Set up some plumbing: teach the svndump lib to pass a file descriptor
number to the fast_export lib, representing where cat-blob/ls
responses can be read from, and add a get_response_line helper
function to the fast_export lib to read a line from that file.
Unfortunately this means that svn-fe needs file descriptor 3 to be
redirected from somewhere (preferrably the cat-blob stream of a
fast-import backend); otherwise it will fail:
$ svndump <path> | svn-fe
fatal: cannot read from file descriptor 3: Bad file descriptor
For the moment, "svn-fe 3</dev/null" works as a workaround but it
will not work for very long. A fast-import backend that can retrieve
old commits is needed in order to be able to fulfill svn
"Node-copyfrom-rev" requests that refer to revs from a previous run.
[jn: with new change description]
Based-on-patch-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: David Barr <david.barr@cordelta.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Collect the line_buffer state in a newly public line_buffer struct.
Callers can use multiple line_buffers to manage input from multiple
files at a time.
svn-fe's delta applier will use this to stream a delta from svnrdump
and the preimage it applies to from fast-import at the same time.
The tests don't take advantage of the new features, but I think that's
okay. It is easier to find lingering examples of nonreentrant code by
searching for "static" in line_buffer.c.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
repo_tree maintains the exporter's state and provides a facility to to
call fast_export, which writes objects to stdout suitable for
consumption by fast-import.
The exported functions roughly correspond to Subversion FS operations.
. repo_add, repo_modify, repo_copy, repo_replace, and repo_delete
update the current commit, based roughly on the corresponding
Subversion FS operation.
. repo_commit calls out to fast_export to write the current commit to
the fast-import stream in stdout.
. repo_diff is used by the fast_export module to write the changes
for a commit.
. repo_reset erases the exporter's state, so valgrind can be happy.
[rr: squelched compiler warnings]
[jn: removed support for maintaining state on-disk, though we may
want to add it back later]
Signed-off-by: David Barr <david.barr@cordelta.com>
Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
