Whenever a fetch results in a packfile being downloaded, a .keep file is
generated, so that the packfile can be preserved (from, say, a running
"git repack") until refs are written referring to the contents of the
packfile.
In a subsequent patch, a successful fetch using protocol v2 may result
in more than one .keep file being generated. Therefore, teach
fetch_pack() and the transport mechanism to support multiple .keep
files.
Implementation notes:
- builtin/fetch-pack.c normally does not generate .keep files, and thus
is unaffected by this or future changes. However, it has an
undocumented "--lock-pack" feature, used by remote-curl.c when
implementing the "fetch" remote helper command. In keeping with the
remote helper protocol, only one "lock" line will ever be written;
the rest will result in warnings to stderr. However, in practice,
warnings will never be written because the remote-curl.c "fetch" is
only used for protocol v0/v1 (which will not generate multiple .keep
files). (Protocol v2 uses the "stateless-connect" command, not the
"fetch" command.)
- connected.c has an optimization in that connectivity checks on a ref
need not be done if the target object is in a pack known to be
self-contained and connected. If there are multiple packfiles, this
optimization can no longer be done.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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