ktest.pl: Add MAIL_PATH option to define where to find the mailer

The option MAIL_PATH lets the user decide how to find the mailer they are
using. For example, sendmail is usually located in /usr/sbin but is not
always in the path of non admin users. Have ktest look through the user's
PATH environment variable (adding /usr/sbin) as well, but if that's not good
enough, allow the user to define where to find the mailer.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

squash to mail exec
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

tools/testing/ktest/ktest.pl

@@ -218,6 +218,7 @@ my $dirname = $FindBin::Bin;
 
 my $mailto;
 my $mailer;
+my $mail_path;
 my $email_on_error;
 my $email_when_finished;
 my $email_when_started;
@@ -252,6 +253,7 @@ my $reboot_success = 0;
 my %option_map = (
     "MAILTO"			=> \$mailto,
     "MAILER"			=> \$mailer,
+    "MAIL_PATH"			=> \$mail_path,
     "EMAIL_ON_ERROR"		=> \$email_on_error,
     "EMAIL_WHEN_FINISHED"	=> \$email_when_finished,
     "EMAIL_WHEN_STARTED"	=> \$email_when_started,
@@ -4126,12 +4128,29 @@ sub set_test_option {
 
 sub _mailx_send {
     my ($subject, $message) = @_;
-    system("$mailer -s \'$subject\' $mailto <<< \'$message\'");
+    system("$mail_path/$mailer -s \'$subject\' $mailto <<< \'$message\'");
 }
 
 sub _sendmail_send {
     my ($subject, $message) = @_;
-    system("echo -e \"Subject: $subject\n\n$message\" | sendmail -t $mailto");
+    system("echo -e \"Subject: $subject\n\n$message\" | $mail_path/sendmail -t $mailto");
+}
+
+sub find_mailer {
+    my ($mailer) = @_;
+
+    my @paths = split /:/, $ENV{PATH};
+
+    # sendmail is usually in /usr/sbin
+    $paths[$#paths + 1] = "/usr/sbin";
+
+    foreach my $path (@paths) {
+	if (-x "$path/$mailer") {
+	    return $path;
+	}
+    }
+
+    return undef;
 }
 
 sub send_email {
@@ -4140,6 +4159,13 @@ sub send_email {
 	    doprint "No email sent: email or mailer not specified in config.\n";
 	    return;
 	}
+	if (!defined($mail_path)) {
+	    # find the mailer
+	    $mail_path = find_mailer $mailer;
+	    if (!defined($mail_path)) {
+		die "\nCan not find $mailer in PATH\n";
+	    }
+	}
         if ($mailer eq "mail" || $mailer eq "mailx"){ _mailx_send(@_);}
         elsif ($mailer eq "sendmail" ) { _sendmail_send(@_);}
         else { doprint "\nYour mailer: $mailer is not supported.\n" }

tools/testing/ktest/sample.conf

@@ -411,6 +411,10 @@
 # (default sendmail)
 #MAILER = sendmail
 #
+# The executable to run
+# (default: for sendmail "/usr/sbin/sendmail", otherwise equals ${MAILER})
+#MAIL_EXEC = /usr/sbin/sendmail
+#
 # Errors are defined as those would terminate the script
 # (default 1)
 #EMAIL_ON_ERROR = 1