[GSoC PATCH v2 1/1] improve smtp authentication error handling logic

[Zheng Yuting <05zyt30@gmail.com>]

---
 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