v2improve smtp auth error handling logic

>
> ---
>  git-send-email.perl | 30 ++++++++++++++++++++++--------
>  1 file changed, 22 insertions(+), 8 deletions(-)
>
> diff --git a/git-send-email.perl b/git-send-email.perl
> index 798d59b84f..a012d61abb 100755
> --- a/git-send-email.perl
> +++ b/git-send-email.perl
> @@ -1419,19 +1419,19 @@ sub smtp_auth_maybe {
>                 die "invalid smtp auth: '${smtp_auth}'";
>         }
>
> -       # TODO: Authentication may fail not because credentials were
> +       # Authentication may fail not because credentials were
>         # invalid but due to other reasons, in which we should not
>         # reject credentials.
>         $auth = Git::credential({
>                 'protocol' => 'smtp',
>                 'host' => smtp_host_string(),
>                 'username' => $smtp_authuser,
> -               # if there's no password, "git credential fill" will
> -               # give us one, otherwise it'll just pass this one.
>                 'password' => $smtp_authpass
> +
>         }, sub {
>                 my $cred = shift;
> -
> +               my $result;
> +               my $error;
>                 if ($smtp_auth) {
>                         my $sasl = Authen::SASL->new(
>                                 mechanism => $smtp_auth,
> @@ -1441,13 +1441,27 @@ sub smtp_auth_maybe {
>                                         authname => $cred->{'username'},
>                                 }
>                         );
> -
>                         return !!$smtp->auth($sasl);
> +               } else {
> +                       # Handle plain authentication errors
> +                       eval {
> +                               $result = $smtp->auth($cred->{'username'}, $cred->{'password'});
> +                               1; # Ensure true value is returned
> +                       } or do {
> +                               $error = $@ || 'Unknown error';
> +                       };
>                 }
> -
> -               return !!$smtp->auth($cred->{'username'}, $cred->{'password'});
> +               # Unified error handling logic
> +               if ($error) {
> +                       # Match temporary errors
> +                       if ($error =~ /timeout|temporary|greylist|throttled|quota\s+exceeded|queue|overload|try\s+again|connection\s+lost|network\s+error/i) {
> +                               warn "SMTP temporary error: $error";
> +                               return 1;
> +                       }
> +                       return 0;
> +               }
> +               return !!$result;
>         });
> -
>         return $auth;
>  }
>
> --
> 2.49.0.rc0.57.gdb91954e18