git-svn: Support retrieving passwords with GIT_ASKPASS

git-svn reads passwords from an interactive terminal.
This behavior cause GUIs to hang waiting for git-svn to
complete

Fix this problem by allowing a password-retrieving command
to be specified in GIT_ASKPASS. SSH_ASKPASS is supported
as a fallback when GIT_ASKPASS is not provided.

Signed-off-by: Frank Li <lznuaa@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/git-svn.perl b/git-svn.perl
index 49dd649bc562ac1b8e5da708ba91572b5e0f0c11..07e95ad449f066ea18e3009f6abae14519c23530 100755 (executable)
--- a/git-svn.perl
+++ b/git-svn.perl
@@ -3970,18 +3970,25 @@ sub username {
 
 sub _read_password {
        my ($prompt, $realm) = @_;
-       print STDERR $prompt;
-       STDERR->flush;
-       require Term::ReadKey;
-       Term::ReadKey::ReadMode('noecho');
        my $password = '';
-       while (defined(my $key = Term::ReadKey::ReadKey(0))) {
-               last if $key =~ /[\012\015]/; # \n\r
-               $password .= $key;
+       if (exists $ENV{GIT_ASKPASS}) {
+               open(PH, "-|", $ENV{GIT_ASKPASS}, $prompt);
+               $password = <PH>;
+               $password =~ s/[\012\015]//; # \n\r
+               close(PH);
+       } else {
+               print STDERR $prompt;
+               STDERR->flush;
+               require Term::ReadKey;
+               Term::ReadKey::ReadMode('noecho');
+               while (defined(my $key = Term::ReadKey::ReadKey(0))) {
+                       last if $key =~ /[\012\015]/; # \n\r
+                       $password .= $key;
+               }
+               Term::ReadKey::ReadMode('restore');
+               print STDERR "\n";
+               STDERR->flush;
        }
-       Term::ReadKey::ReadMode('restore');
-       print STDERR "\n";
-       STDERR->flush;
        $password;
 }