feature detection for digital voice; display modulator buttons only when

available

htdocs/index.html

@@ -91,12 +91,16 @@
                         <div class="openwebrx-button openwebrx-demodulator-button" id="openwebrx-button-cw"
                             onclick="demodulator_analog_replace('cw');">CW</div>
 						<div class="openwebrx-button openwebrx-demodulator-button" id="openwebrx-button-dmr"
+                             style="display:none;" data-feature="digital_voice"
 						    onclick="demodulator_analog_replace('dmr');">DMR</div>
 						<div class="openwebrx-button openwebrx-demodulator-button" id="openwebrx-button-dstar"
+                             style="display:none;" data-feature="digital_voice"
 						    onclick="demodulator_analog_replace('dstar');">DStar</div>
 						<div class="openwebrx-button openwebrx-demodulator-button" id="openwebrx-button-nxdn"
+                             style="display:none;" data-feature="digital_voice"
 						    onclick="demodulator_analog_replace('nxdn');">NXDN</div>
 						<div class="openwebrx-button openwebrx-demodulator-button" id="openwebrx-button-ysf"
+                             style="display:none;" data-feature="digital_voice"
 						    onclick="demodulator_analog_replace('ysf');">YSF</div>
                     </div>
                     <div class="openwebrx-panel-line">

htdocs/openwebrx.js

@@ -1233,6 +1233,11 @@ function on_ws_recv(evt)
                             return '<option value="' + profile.id + '">' + profile.name + "</option>";
                         }).join("");
                     break;
+					case "features":
+						for (var feature in json.value) {
+							$('[data-feature="' + feature + '"')[json.value[feature] ? "show" : "hide"]();
+						}
+					break;
                     default:
                         console.warn('received message of unknown type: ' + json.type);
 		        }

owrx/connection.py

@@ -1,5 +1,6 @@
 from owrx.config import PropertyManager
 from owrx.source import DspManager, CpuUsageThread, SdrService, ClientRegistry
+from owrx.feature import FeatureDetector
 import json
 
 import logging
@@ -33,6 +34,9 @@ class OpenWebRxClient(object):
         profiles = [{"name": s.getName() + " " + p["name"], "id":sid + "|" + pid} for (sid, s) in SdrService.getSources().items() for (pid, p) in s.getProfiles().items()]
         self.write_profiles(profiles)
 
+        features = FeatureDetector().feature_availability()
+        self.write_features(features)
+
         CpuUsageThread.getSharedInstance().add_client(self)
 
     def sendConfig(self, key, value):
@@ -121,6 +125,8 @@ class OpenWebRxClient(object):
         self.protected_send({"type":"receiver_details","value":details})
     def write_profiles(self, profiles):
         self.protected_send({"type":"profiles","value":profiles})
+    def write_features(self, features):
+        self.protected_send({"type":"features","value":features})
 
 class WebSocketMessageHandler(object):
     def __init__(self):

owrx/feature.py

@@ -1,4 +1,7 @@
 import os
+import subprocess
+from functools import reduce
+from operator import and_
 
 import logging
 logger = logging.getLogger(__name__)
@@ -12,9 +15,13 @@ class FeatureDetector(object):
         "core": [ "csdr", "nmux" ],
         "rtl_sdr": [ "rtl_sdr" ],
         "sdrplay": [ "rx_tools" ],
-        "hackrf": [ "hackrf_transfer" ]
+        "hackrf": [ "hackrf_transfer" ],
+        "digital_voice": [ "digiham" ]
     }
 
+    def feature_availability(self):
+        return {name: self.is_available(name) for name in FeatureDetector.features}
+
     def is_available(self, feature):
         return self.has_requirements(self.get_requirements(feature))
 
@@ -34,17 +41,20 @@ class FeatureDetector(object):
                 logger.error("detection of requirement {0} not implement. please fix in code!".format(requirement))
         return passed
 
+    def command_is_runnable(self, command):
+        return os.system("{0} 2>/dev/null >/dev/null".format(command)) != 32512
+
     def has_csdr(self):
-        return os.system("csdr 2> /dev/null") != 32512
+        return self.command_is_runnable("csdr")
 
     def has_nmux(self):
-        return os.system("nmux --help 2> /dev/null") != 32512
+        return self.command_is_runnable("nmux --help")
 
     def has_rtl_sdr(self):
-        return os.system("rtl_sdr --help 2> /dev/null") != 32512
+        return self.command_is_runnable("rtl_sdr --help")
 
     def has_rx_tools(self):
-        return os.system("rx_sdr --help 2> /dev/null") != 32512
+        return self.command_is_runnable("rx_sdr --help")
 
     """
     To use a HackRF, compile the HackRF host tools from its "stdout" branch:
@@ -62,4 +72,29 @@ class FeatureDetector(object):
     def has_hackrf_transfer(self):
         # TODO i don't have a hackrf, so somebody doublecheck this.
         # TODO also check if it has the stdout feature
-        return os.system("hackrf_transfer --help 2> /dev/null") != 32512
+        return self.command_is_runnable("hackrf_transfer --help")
+
+    def command_exists(self, command):
+        return os.system("which {0}".format(command)) == 0
+
+    def has_digiham(self):
+        # the digiham tools expect to be fed via stdin, they will block until their stdin is closed.
+        def check_with_stdin(command):
+            try:
+                process = subprocess.Popen(command, stdin=subprocess.PIPE)
+                process.communicate("")
+                return process.wait() == 0
+            except FileNotFoundError:
+                return False
+        return reduce(and_,
+                      map(
+                          check_with_stdin,
+                          ["rrc_filter", "ysf_decoder", "dmr_decoder", "mbe_synthesizer"]
+                      ),
+                      True)
+
+    def has_dsd(self):
+        return self.command_is_runnable("dsd")
+
+    def has_sox(self):
+        return self.command_is_runnable("sox")