1 files changed, 40 insertions, 4 deletions

diff --git a/src/core/transport/connectivity_state.c b/src/core/transport/connectivity_state.c
index 1091ceae44..61d26f06f0 100644
--- a/src/core/transport/connectivity_state.c
+++ b/src/core/transport/connectivity_state.c
@@ -34,11 +34,33 @@
 #include "src/core/transport/connectivity_state.h"
 #include <grpc/support/alloc.h>
 #include <grpc/support/log.h>
+#include <grpc/support/string_util.h>
+
+int grpc_connectivity_state_trace = 0;
+
+const char *grpc_connectivity_state_name(grpc_connectivity_state state) {
+  switch (state) {
+    case GRPC_CHANNEL_IDLE:
+      return "IDLE";
+    case GRPC_CHANNEL_CONNECTING:
+      return "CONNECTING";
+    case GRPC_CHANNEL_READY:
+      return "READY";
+    case GRPC_CHANNEL_TRANSIENT_FAILURE:
+      return "TRANSIENT_FAILURE";
+    case GRPC_CHANNEL_FATAL_FAILURE:
+      return "FATAL_FAILURE";
+  }
+  abort();
+  return "UNKNOWN";
+}
 
 void grpc_connectivity_state_init(grpc_connectivity_state_tracker *tracker,
-                                  grpc_connectivity_state init_state) {
+                                  grpc_connectivity_state init_state,
+                                  const char *name) {
   tracker->current_state = init_state;
   tracker->watchers = NULL;
+  tracker->name = gpr_strdup(name);
 }
 
 void grpc_connectivity_state_destroy(grpc_connectivity_state_tracker *tracker) {
@@ -54,6 +76,7 @@ void grpc_connectivity_state_destroy(grpc_connectivity_state_tracker *tracker) {
     }
     gpr_free(w);
   }
+  gpr_free(tracker->name);
 }
 
 grpc_connectivity_state grpc_connectivity_state_check(
@@ -64,6 +87,11 @@ grpc_connectivity_state grpc_connectivity_state_check(
 int grpc_connectivity_state_notify_on_state_change(
     grpc_connectivity_state_tracker *tracker, grpc_connectivity_state *current,
     grpc_iomgr_closure *notify) {
+  if (grpc_connectivity_state_trace) {
+    gpr_log(GPR_DEBUG, "CONWATCH: %s: from %s [cur=%s]", tracker->name,
+            grpc_connectivity_state_name(*current),
+            grpc_connectivity_state_name(tracker->current_state));
+  }
   if (tracker->current_state != *current) {
     *current = tracker->current_state;
     grpc_iomgr_add_callback(notify);
@@ -79,12 +107,19 @@ int grpc_connectivity_state_notify_on_state_change(
 
 void grpc_connectivity_state_set_with_scheduler(
     grpc_connectivity_state_tracker *tracker, grpc_connectivity_state state,
-    void (*scheduler)(void *arg, grpc_iomgr_closure *closure), void *arg) {
+    void (*scheduler)(void *arg, grpc_iomgr_closure *closure), void *arg,
+    const char *reason) {
   grpc_connectivity_state_watcher *new = NULL;
   grpc_connectivity_state_watcher *w;
+  if (grpc_connectivity_state_trace) {
+    gpr_log(GPR_DEBUG, "SET: %s: %s --> %s [%s]", tracker->name,
+            grpc_connectivity_state_name(tracker->current_state),
+            grpc_connectivity_state_name(state), reason);
+  }
   if (tracker->current_state == state) {
     return;
   }
+  GPR_ASSERT(tracker->current_state != GRPC_CHANNEL_FATAL_FAILURE);
   tracker->current_state = state;
   while ((w = tracker->watchers)) {
     tracker->watchers = w->next;
@@ -106,7 +141,8 @@ static void default_scheduler(void *ignored, grpc_iomgr_closure *closure) {
 }
 
 void grpc_connectivity_state_set(grpc_connectivity_state_tracker *tracker,
-                                 grpc_connectivity_state state) {
+                                 grpc_connectivity_state state,
+                                 const char *reason) {
   grpc_connectivity_state_set_with_scheduler(tracker, state, default_scheduler,
-                                             NULL);
+                                             NULL, reason);
 }