2 files changed, 27 insertions, 0 deletions
diff --git a/gnuradio-runtime/lib/constants.cc.in b/gnuradio-runtime/lib/constants.cc.in
index 516e2f8798..b368e9dc3f 100644
--- a/gnuradio-runtime/lib/constants.cc.in
+++ b/gnuradio-runtime/lib/constants.cc.in
@@ -24,6 +24,7 @@
 #include <config.h>
 #endif
 
+#include <stdlib.h>
 #include <gnuradio/constants.h>
 
 namespace gr {
@@ -31,18 +32,36 @@ namespace gr {
   const std::string
   prefix()
   {
+    //Use "GR_PREFIX" environment variable when specified
+    const char *prefix = getenv("GR_PREFIX");
+    if (prefix != NULL) return prefix;
+
     return "@prefix@";
   }
 
   const std::string
   sysconfdir()
   {
+    //Provide the sysconfdir in terms of prefix()
+    //when the "GR_PREFIX" environment var is specified.
+    if (getenv("GR_PREFIX") != NULL)
+    {
+      return prefix() + "/@GR_CONF_DIR@";
+    }
+
     return "@SYSCONFDIR@";
   }
 
   const std::string
   prefsdir()
   {
+    //Provide the prefsdir in terms of sysconfdir()
+    //when the "GR_PREFIX" environment var is specified.
+    if (getenv("GR_PREFIX") != NULL)
+    {
+      return sysconfdir() + "/@CMAKE_PROJECT_NAME@/conf.d";
+    }
+
     return "@GR_PREFSDIR@";
   }
 
diff --git a/gr-digital/lib/msk_timing_recovery_cc_impl.cc b/gr-digital/lib/msk_timing_recovery_cc_impl.cc
index 4b26573870..1473aa88c5 100644
--- a/gr-digital/lib/msk_timing_recovery_cc_impl.cc
+++ b/gr-digital/lib/msk_timing_recovery_cc_impl.cc
@@ -145,8 +145,16 @@ namespace gr {
                        tags.erase(tags.begin());
                        goto out;
                     }
+                    if(std::abs(center) >= 1.0f) {
+                        GR_LOG_WARN(d_logger, boost::format("work: ignoring time_est tag "
+                                                            "(%.2f) outside of (-1, 1)") \
+                                    % center);
+                        tags.erase(tags.begin());
+                        goto out;
+                    }
                     d_mu = center;
                     iidx = offset;
+                    //we want positive mu, so offset iidx to compensate
                     if(d_mu<0) {
                         d_mu++;
                         iidx--;