flow_control: implement pass / drop filtering policies

This change introduces a set of three modes for flow control
filters, one of which is default behavor and two extra modes
else described below:

  - FILTER_POLICY_PASS_ALL
  - FILTER_POLICY_DROP_ALL

Both modes are opposite, and make a filter either unconditionally
pass or drop all the data one gets to the input. They would be
usable for some external usage.

6 files changed, 60 insertions, 0 deletions

diff --git a/include/grgsm/flow_control/CMakeLists.txt b/include/grgsm/flow_control/CMakeLists.txt
index 9c20b59..322c8c8 100644
--- a/include/grgsm/flow_control/CMakeLists.txt
+++ b/include/grgsm/flow_control/CMakeLists.txt
@@ -21,6 +21,7 @@
 # Install public header files
 ########################################################################
 install(FILES
+    common.h
     burst_timeslot_splitter.h
     burst_sdcch_subslot_splitter.h
     burst_timeslot_filter.h
diff --git a/include/grgsm/flow_control/burst_fnr_filter.h b/include/grgsm/flow_control/burst_fnr_filter.h
index dd60830..0d94ff8 100644
--- a/include/grgsm/flow_control/burst_fnr_filter.h
+++ b/include/grgsm/flow_control/burst_fnr_filter.h
@@ -26,6 +26,7 @@
 
 #include <grgsm/api.h>
 #include <gnuradio/block.h>
+#include <grgsm/flow_control/common.h>
 
 namespace gr {
   namespace gsm {
@@ -62,6 +63,10 @@ namespace gr {
 
       virtual filter_mode get_mode(void) = 0;
       virtual filter_mode set_mode(filter_mode mode) = 0;
+
+      /* Filtering policy */
+      virtual filter_policy get_policy(void) = 0;
+      virtual filter_policy set_policy(filter_policy policy) = 0;
     };
 
   } // namespace gsm
diff --git a/include/grgsm/flow_control/burst_sdcch_subslot_filter.h b/include/grgsm/flow_control/burst_sdcch_subslot_filter.h
index 5bcf829..a68782f 100644
--- a/include/grgsm/flow_control/burst_sdcch_subslot_filter.h
+++ b/include/grgsm/flow_control/burst_sdcch_subslot_filter.h
@@ -25,6 +25,7 @@
 
 #include <grgsm/api.h>
 #include <gnuradio/block.h>
+#include <grgsm/flow_control/common.h>
 
 namespace gr {
   namespace gsm {
@@ -61,6 +62,10 @@ namespace gr {
 
       virtual subslot_filter_mode get_mode(void) = 0;
       virtual subslot_filter_mode set_mode(subslot_filter_mode mode) = 0;
+
+      /* Filtering policy */
+      virtual filter_policy get_policy(void) = 0;
+      virtual filter_policy set_policy(filter_policy policy) = 0;
     };
   } // namespace gsm
 } // namespace gr
diff --git a/include/grgsm/flow_control/burst_timeslot_filter.h b/include/grgsm/flow_control/burst_timeslot_filter.h
index 2f16b77..79d677c 100644
--- a/include/grgsm/flow_control/burst_timeslot_filter.h
+++ b/include/grgsm/flow_control/burst_timeslot_filter.h
@@ -25,6 +25,7 @@
 
 #include <grgsm/api.h>
 #include <gnuradio/block.h>
+#include <grgsm/flow_control/common.h>
 
 namespace gr {
   namespace gsm {
@@ -52,6 +53,10 @@ namespace gr {
       /* External API */
       virtual unsigned int get_tn(void) = 0;
       virtual unsigned int set_tn(unsigned int tn) = 0;
+
+      /* Filtering policy */
+      virtual filter_policy get_policy(void) = 0;
+      virtual filter_policy set_policy(filter_policy policy) = 0;
     };
   } // namespace gsm
 } // namespace gr
diff --git a/include/grgsm/flow_control/common.h b/include/grgsm/flow_control/common.h
new file mode 100644
index 0000000..fa4725c
--- /dev/null
+++ b/include/grgsm/flow_control/common.h
@@ -0,0 +1,38 @@
+/* -*- c++ -*- */
+/*
+ * @file
+ * @author Vadim Yanitskiy <axilirator@gmail.com>
+ * @section LICENSE
+ *
+ * Gr-gsm is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3, or (at your option)
+ * any later version.
+ *
+ * Gr-gsm is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with gr-gsm; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifndef INCLUDED_GSM_FLOW_CONTROL_COMMON_H
+#define INCLUDED_GSM_FLOW_CONTROL_COMMON_H
+
+namespace gr {
+  namespace gsm {
+
+    enum filter_policy {
+      FILTER_POLICY_DEFAULT,
+      FILTER_POLICY_PASS_ALL,
+      FILTER_POLICY_DROP_ALL,
+    };
+
+  } /* namespace gsm */
+} /* namespace gr */
+
+#endif
diff --git a/include/grgsm/flow_control/dummy_burst_filter.h b/include/grgsm/flow_control/dummy_burst_filter.h
index b969611..bf956bb 100644
--- a/include/grgsm/flow_control/dummy_burst_filter.h
+++ b/include/grgsm/flow_control/dummy_burst_filter.h
@@ -25,6 +25,7 @@
 
 #include <grgsm/api.h>
 #include <gnuradio/block.h>
+#include <grgsm/flow_control/common.h>
 
 namespace gr {
   namespace gsm {
@@ -48,6 +49,11 @@ namespace gr {
        * creating new instances.
        */
       static sptr make();
+
+      /* External API */
+      /* Filtering policy */
+      virtual filter_policy get_policy(void) = 0;
+      virtual filter_policy set_policy(filter_policy policy) = 0;
     };
   } // namespace gsm
 } // namespace gr