From a844b7406f17ac6e069e617509a2997d7e128500 Mon Sep 17 00:00:00 2001 From: Simon Hausmann Date: Mon, 7 May 2007 20:14:17 +0200 Subject: [PATCH] Document some implementation details, for the curious... :) Signed-off-by: Simon Hausmann --- contrib/fast-import/git-p4.txt | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/contrib/fast-import/git-p4.txt b/contrib/fast-import/git-p4.txt index d36a1cf18c..ff0da9d0c8 100644 --- a/contrib/fast-import/git-p4.txt +++ b/contrib/fast-import/git-p4.txt @@ -121,3 +121,20 @@ Example git-p4 rebase +Implementation Details... +========================= + +* Changesets from Perforce are imported using git fast-import. +* The import does not require anything from the Perforce client view as it just uses + "p4 print //depot/path/file#revision" to get the actual file contents. +* Every imported changeset has a special [git-p4...] line at the + end of the log message that gives information about the corresponding + Perforce change number and is also used by git-p4 itself to find out + where to continue importing when doing incremental imports. + Basically when syncing it extracts the perforce change number of the + latest commit in the "p4" branch and uses "p4 changes //depot/path/...@changenum,#head" + to find out which changes need to be imported. +* git-p4 submit uses "git rev-list" to pick the commits between the "p4" branch + and the current branch. + The commits themselves are applied using git diff-tree ... | patch -p1 +