X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=Debian%2FDgit.pm;h=2ef32f32a8179f9dc590bfdbcf27419470a62f21;hb=4615f2d1c695caf9b04719f51d57dfae539bb712;hp=19ea85b6ebe887c36ead2c44a6d409a17e5bfee6;hpb=89906fd58100567b415f9c13d83121b988dfa325;p=dgit.git

diff --git a/Debian/Dgit.pm b/Debian/Dgit.pm
index 19ea85b6..2ef32f32 100644
--- a/Debian/Dgit.pm
+++ b/Debian/Dgit.pm
@@ -54,7 +54,7 @@ BEGIN {
                       waitstatusmsg failedcmd_waitstatus
 		      failedcmd_report_cmd failedcmd
                       runcmd shell_cmd cmdoutput cmdoutput_errok
-                      git_rev_parse git_cat_file
+                      git_rev_parse changedir_git_toplevel git_cat_file
 		      git_get_ref git_get_symref git_for_each_ref
                       git_for_each_tag_referring is_fast_fwd
 		      git_check_unmodified
@@ -98,7 +98,7 @@ our $distro_re = $component_re;
 our $versiontag_re = qr{[-+.\%_0-9a-zA-Z/]+};
 our $branchprefix = 'dgit';
 our $series_filename_re = qr{(?:^|\.)series(?!\n)$}s;
-our $extra_orig_namepart_re = qr{[-0-9a-z]+};
+our $extra_orig_namepart_re = qr{[-0-9a-zA-Z]+};
 our $orig_f_comp_re = qr{orig(?:-$extra_orig_namepart_re)?};
 our $orig_f_sig_re = '\\.(?:asc|gpg|pgp)';
 our $orig_f_tail_re = "$orig_f_comp_re\\.tar(?:\\.\\w+)?(?:$orig_f_sig_re)?";
@@ -434,6 +434,8 @@ sub rename_link_xf ($$$) {
     #    $@ to a reason message
     #    $! to an errno value, or -1 if not known
     # having possibly printed something about mv to stderr.
+    # Not safe to use without $keeporig if $dst might be a symlink
+    # to $src, as it might delete $src leaving $dst invalid.
     my ($keeporig,$src,$dst) = @_;
     if ($keeporig
 	? link   $src, $dst
@@ -444,19 +446,40 @@ sub rename_link_xf ($$$) {
 	$@ = "$!";
 	return 0;
     }
-    $!=0; $?=0;
-    my @cmd = (qw(cp --), $src, "$dst.tmp");
-    debugcmd '+',@cmd;
-    if (system @cmd) {
-	failedcmd_report_cmd undef, @cmd;
-	$@ = failedcmd_waitstatus();
-	$! = -1;
+    if (!stat $src) {
+	$@ = f_ "stat source file: %S", $!;
 	return 0;
     }
-    if (!rename "$dst.tmp", $dst) {
-	$@ = f_ "finally install file after cp: %S", $!;
+    my @src_stat = (stat _)[0..1];
+
+    my @dst_stat;
+    if (stat $dst) {
+	@dst_stat = (stat _)[0..1];
+    } elsif ($! == ENOENT) {
+    } else {
+	$@ = f_ "stat destination file: %S", $!;
 	return 0;
     }
+
+    if ("@src_stat" eq "@dst_stat") {
+	# (Symlinks to) the same file.  No need for a copy but
+	# we may need to delete the original.
+	printdebug "rename_link_xf $keeporig $src $dst EXDEV but same\n";
+    } else {
+	$!=0; $?=0;
+	my @cmd = (qw(cp --), $src, "$dst.tmp");
+	debugcmd '+',@cmd;
+	if (system @cmd) {
+	    failedcmd_report_cmd undef, @cmd;
+	    $@ = failedcmd_waitstatus();
+	    $! = -1;
+	    return 0;
+	}
+	if (!rename "$dst.tmp", $dst) {
+	    $@ = f_ "finally install file after cp: %S", $!;
+	    return 0;
+	}
+    }
     if (!$keeporig) {
 	if (!unlink $src) {
 	    $@ = f_ "delete old file after cp: %S", $!;
@@ -477,6 +500,15 @@ sub git_rev_parse ($) {
     return cmdoutput qw(git rev-parse), "$_[0]~0";
 }
 
+sub changedir_git_toplevel () {
+    my $toplevel = cmdoutput qw(git rev-parse --show-toplevel);
+    length $toplevel or fail __ <<END;
+not in a git working tree?
+(git rev-parse --show-toplevel produced no output)
+END
+    chdir $toplevel or fail f_ "chdir toplevel %s: %s\n", $toplevel, $!;
+}
+
 sub git_cat_file ($;$) {
     my ($objname, $etype) = @_;
     # => ($type, $data) or ('missing', undef)