diff --git a/git-cvsserver.perl b/git-cvsserver.perl index 53d8de7f8b..7bb6f83b9d 100755 --- a/git-cvsserver.perl +++ b/git-cvsserver.perl @@ -4041,6 +4041,19 @@ =head2 getmeta This function takes a filename (with path) argument and returns a hashref of metadata for that file. +There are several ways $revision can be specified: + + - A reference to hash that contains a "tag" that is the + actual revision (one of the below). TODO: Also allow it to + specify a "date" in the hash. + - undef, to refer to the latest version on the main branch. + - Full CVS client revision number (mapped to integer in DB, without the + "1." prefix), + - Complex CVS-compatible "special" revision number for + non-linear history (see comment below) + - git commit sha1 hash + - branch or tag name + =cut sub getmeta @@ -4051,23 +4064,144 @@ sub getmeta my $tablename_rev = $self->tablename("revision"); my $tablename_head = $self->tablename("head"); - my $db_query; - if ( defined($revision) and $revision =~ /^1\.(\d+)$/ ) + if ( ref($revision) eq "HASH" ) { - my ($intRev) = $1; - $db_query = $self->{dbh}->prepare_cached("SELECT * FROM $tablename_rev WHERE name=? AND revision=?",{},1); - $db_query->execute($filename, $intRev); - } - elsif ( defined($revision) and $revision =~ /^[a-zA-Z0-9]{40}$/ ) - { - $db_query = $self->{dbh}->prepare_cached("SELECT * FROM $tablename_rev WHERE name=? AND commithash=?",{},1); - $db_query->execute($filename, $revision); - } else { - $db_query = $self->{dbh}->prepare_cached("SELECT * FROM $tablename_head WHERE name=?",{},1); - $db_query->execute($filename); + $revision = $revision->{tag}; + } + + # Overview of CVS revision numbers: + # + # General CVS numbering scheme: + # - Basic mainline branch numbers: "1.1", "1.2", "1.3", etc. + # - Result of "cvs checkin -r" (possible, but not really + # recommended): "2.1", "2.2", etc + # - Branch tag: "1.2.0.n", where "1.2" is revision it was branched + # from, "0" is a magic placeholder that identifies it as a + # branch tag instead of a version tag, and n is 2 times the + # branch number off of "1.2", starting with "2". + # - Version on a branch: "1.2.n.x", where "1.2" is branch-from, "n" + # is branch number off of "1.2" (like n above), and "x" is + # the version number on the branch. + # - Branches can branch off of branches: "1.3.2.7.4.1" (even number + # of components). + # - Odd "n"s are used by "vendor branches" that result + # from "cvs import". Vendor branches have additional + # strangeness in the sense that the main rcs "head" of the main + # branch will (temporarily until first normal commit) point + # to the version on the vendor branch, rather than the actual + # main branch. (FUTURE: This may provide an opportunity + # to use "strange" revision numbers for fast-forward-merged + # branch tip when CVS client is asking for the main branch.) + # + # git-cvsserver CVS-compatible special numbering schemes: + # - Currently git-cvsserver only tries to be identical to CVS for + # simple "1.x" numbers on the "main" branch (as identified + # by the module name that was originally cvs checkout'ed). + # - The database only stores the "x" part, for historical reasons. + # But most of the rest of the cvsserver preserves + # and thinks using the full revision number. + # - To handle non-linear history, it uses a version of the form + # "2.1.1.2000.b.b.b."..., where the 2.1.1.2000 is to help uniquely + # identify this as a special revision number, and there are + # 20 b's that together encode the sha1 git commit from which + # this version of this file originated. Each b is + # the numerical value of the corresponding byte plus + # 100. + # - "plus 100" avoids "0"s, and also reduces the + # likelyhood of a collision in the case that someone someday + # writes an import tool that tries to preserve original + # CVS revision numbers, and the original CVS data had done + # lots of branches off of branches and other strangeness to + # end up with a real version number that just happens to look + # like this special revision number form. Also, if needed + # there are several ways to extend/identify alternative encodings + # within the "2.1.1.2000" part if necessary. + # - Unlike real CVS revisions, you can't really reconstruct what + # relation a revision of this form has to other revisions. + # - FUTURE: TODO: Rework database somehow to make up and remember + # fully-CVS-compatible branches and branch version numbers. + + my $meta; + if ( defined($revision) ) + { + if ( $revision =~ /^1\.(\d+)$/ ) + { + my ($intRev) = $1; + my $db_query; + $db_query = $self->{dbh}->prepare_cached( + "SELECT * FROM $tablename_rev WHERE name=? AND revision=?", + {},1); + $db_query->execute($filename, $intRev); + $meta = $db_query->fetchrow_hashref; + } + elsif ( $revision =~ /^2\.1\.1\.2000(\.[1-3][0-9][0-9]){20}$/ ) + { + my ($commitHash)=($revision=~/^2\.1\.1\.2000(.*)$/); + $commitHash=~s/\.([0-9]+)/sprintf("%02x",$1-100)/eg; + if($commitHash=~/^[0-9a-f]{40}$/) + { + return $self->getMetaFromCommithash($filename,$commitHash); + } + + # error recovery: fall back on head version below + print "E Failed to find $filename version=$revision or commit=$commitHash\n"; + $log->warning("failed get $revision with commithash=$commitHash"); + undef $revision; + } + elsif ( $revision =~ /^[0-9a-f]{40}$/ ) + { + # Try DB first. This is mostly only useful for req_annotate(), + # which only calls this for stuff that should already be in + # the DB. It is fairly likely to be a waste of time + # in most other cases [unless the file happened to be + # modified in $revision specifically], but + # it is probably in the noise compared to how long + # getMetaFromCommithash() will take. + my $db_query; + $db_query = $self->{dbh}->prepare_cached( + "SELECT * FROM $tablename_rev WHERE name=? AND commithash=?", + {},1); + $db_query->execute($filename, $revision); + $meta = $db_query->fetchrow_hashref; + + if(! $meta) + { + my($revCommit)=$self->lookupCommitRef($revision); + if($revCommit=~/^[0-9a-f]{40}$/) + { + return $self->getMetaFromCommithash($filename,$revCommit); + } + + # error recovery: nothing found: + print "E Failed to find $filename version=$revision\n"; + $log->warning("failed get $revision"); + return $meta; + } + } + else + { + my($revCommit)=$self->lookupCommitRef($revision); + if($revCommit=~/^[0-9a-f]{40}$/) + { + return $self->getMetaFromCommithash($filename,$revCommit); + } + + # error recovery: fall back on head version below + print "E Failed to find $filename version=$revision\n"; + $log->warning("failed get $revision"); + undef $revision; # Allow fallback + } + } + + if(!defined($revision)) + { + my $db_query; + $db_query = $self->{dbh}->prepare_cached( + "SELECT * FROM $tablename_head WHERE name=?",{},1); + $db_query->execute($filename); + $meta = $db_query->fetchrow_hashref; } - my $meta = $db_query->fetchrow_hashref; if($meta) { $meta->{revision} = "1.$meta->{revision}";