push: support pushing HEAD to real branch name

diff --git a/git-cvsexportcommit.perl b/git-cvsexportcommit.perl
index 7b19a33ad1cceaf61793be4e16e4b144d415a975..92e41620fd2a998e765a47c2c2ca7085834b14cc 100755 (executable)
--- a/git-cvsexportcommit.perl
+++ b/git-cvsexportcommit.perl
@@ -1,28 +1,42 @@
 #!/usr/bin/perl -w
 
-# Known limitations:
-# - does not propagate permissions
-# - error handling has not been extensively tested
-#
-
 use strict;
 use Getopt::Std;
 use File::Temp qw(tempdir);
 use Data::Dumper;
 use File::Basename qw(basename dirname);
 
-unless ($ENV{GIT_DIR} && -r $ENV{GIT_DIR}){
-    die "GIT_DIR is not defined or is unreadable";
-}
+our ($opt_h, $opt_P, $opt_p, $opt_v, $opt_c, $opt_f, $opt_a, $opt_m, $opt_d, $opt_u, $opt_w);
 
-our ($opt_h, $opt_P, $opt_p, $opt_v, $opt_c, $opt_f, $opt_a, $opt_m, $opt_d, $opt_u);
-
-getopts('uhPpvcfam:d:');
+getopts('uhPpvcfam:d:w:');
 
 $opt_h && usage();
 
 die "Need at least one commit identifier!" unless @ARGV;
 
+if ($opt_w) {
+       unless ($ENV{GIT_DIR}) {
+               # Remember where our GIT_DIR is before changing to CVS checkout
+               my $gd =`git-rev-parse --git-dir`;
+               chomp($gd);
+               if ($gd eq '.git') {
+                       my $wd = `pwd`;
+                       chomp($wd);
+                       $gd = $wd."/.git"       ;
+               }
+               $ENV{GIT_DIR} = $gd;
+       }
+
+       if (! -d $opt_w."/CVS" ) {
+               die "$opt_w is not a CVS checkout";
+       }
+       chdir $opt_w or die "Cannot change to CVS checkout at $opt_w";
+}
+unless ($ENV{GIT_DIR} && -r $ENV{GIT_DIR}){
+    die "GIT_DIR is not defined or is unreadable";
+}
+
+
 my @cvs;
 if ($opt_d) {
        @cvs = ('cvs', '-d', $opt_d);
@@ -30,11 +44,6 @@
        @cvs = ('cvs');
 }
 
-# setup a tempdir
-our ($tmpdir, $tmpdirname) = tempdir('git-cvsapplycommit-XXXXXX',
-                                    TMPDIR => 1,
-                                    CLEANUP => 1);
-
 # resolve target commit
 my $commit;
 $commit = pop @ARGV;
@@ -87,6 +96,7 @@
     }
 }
 
+my $noparent = "0000000000000000000000000000000000000000";
 if ($parent) {
     my $found;
     # double check that it's a valid parent
@@ -100,8 +110,10 @@
 } else { # we don't have a parent from the cmdline...
     if (@parents == 1) { # it's safe to get it from the commit
        $parent = $parents[0];
-    } else { # or perhaps not!
-       die "This commit has more than one parent -- please name the parent you want to use explicitly";
+    } elsif (@parents == 0) { # there is no parent
+        $parent = $noparent;
+    } else { # cannot choose automatically from multiple parents
+        die "This commit has more than one parent -- please name the parent you want to use explicitly";
     }
 }
 
@@ -121,7 +133,11 @@
 }
 close MSG;
 
-`git-diff-tree --binary -p $parent $commit >.cvsexportcommit.diff`;# || die "Cannot diff";
+if ($parent eq $noparent) {
+    `git-diff-tree --binary -p --root $commit >.cvsexportcommit.diff`;# || die "Cannot diff";
+} else {
+    `git-diff-tree --binary -p $parent $commit >.cvsexportcommit.diff`;# || die "Cannot diff";
+}
 
 ## apply non-binary changes
 
@@ -134,7 +150,7 @@
 print "Checking if patch will apply\n";
 
 my @stat;
-open APPLY, "GIT_DIR= git-apply $context --binary --summary --numstat<.cvsexportcommit.diff|" || die "cannot patch";
+open APPLY, "GIT_DIR= git-apply $context --summary --numstat<.cvsexportcommit.diff|" || die "cannot patch";
 @stat=<APPLY>;
 close APPLY || die "Cannot patch";
 my (@bfiles,@files,@afiles,@dfiles);
@@ -220,7 +236,7 @@
 }
 
 print "Applying\n";
-`GIT_DIR= git-apply $context --binary --summary --numstat --apply <.cvsexportcommit.diff` || die "cannot patch";
+`GIT_DIR= git-apply $context --summary --numstat --apply <.cvsexportcommit.diff` || die "cannot patch";
 
 print "Patch applied successfully. Adding new files and directories to CVS\n";
 my $dirtypatch = 0;
@@ -272,6 +288,7 @@
     print "You'll need to apply the patch in .cvsexportcommit.diff manually\n";
     print "using a patch program. After applying the patch and resolving the\n";
     print "problems you may commit using:";
+    print "\n    cd \"$opt_w\"" if $opt_w;
     print "\n    $cmd\n\n";
     exit(1);
 }
@@ -299,7 +316,7 @@
 
 sub usage {
        print STDERR <<END;
-Usage: GIT_DIR=/path/to/.git ${\basename $0} [-h] [-p] [-v] [-c] [-f] [-m msgprefix] [ parent ] commit
+Usage: GIT_DIR=/path/to/.git ${\basename $0} [-h] [-p] [-v] [-c] [-f] [-u] [-w cvsworkdir] [-m msgprefix] [ parent ] commit
 END
        exit(1);
 }