server-mode: Report watched files to client

* Add a command to report watched files and directories to clients.

Help/manual/cmake-server.7.rst

@@ -635,3 +635,26 @@ CMake will respond with the following output::
 
 The output can be limited to a list of keys by passing an array of key names
 to the "keys" optional field of the "cache" request.
+
+
+Type "fileSystemWatchers"
+^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The server can watch the filesystem for changes. The "fileSystemWatchers"
+command will report on the files and directories watched.
+
+Example::
+
+  [== CMake Server ==]
+  {"type":"fileSystemWatchers"}
+  [== CMake Server ==]
+
+CMake will respond with the following output::
+
+  [== CMake Server ==]
+  {
+    "cookie":"","inReplyTo":"fileSystemWatchers","type":"reply",
+    "watchedFiles": [ "/absolute/path" ],
+    "watchedDirectories": [ "/absolute" ]
+  }
+  [== CMake Server ==]

Source/cmServerDictionary.h

@@ -12,6 +12,7 @@ static const std::string kCODE_MODEL_TYPE = "codemodel";
 static const std::string kCOMPUTE_TYPE = "compute";
 static const std::string kCONFIGURE_TYPE = "configure";
 static const std::string kERROR_TYPE = "error";
+static const std::string kFILESYSTEM_WATCHERS_TYPE = "fileSystemWatchers";
 static const std::string kGLOBAL_SETTINGS_TYPE = "globalSettings";
 static const std::string kHANDSHAKE_TYPE = "handshake";
 static const std::string kMESSAGE_TYPE = "message";
@@ -80,6 +81,8 @@ static const std::string kVALUE_KEY = "value";
 static const std::string kWARN_UNINITIALIZED_KEY = "warnUninitialized";
 static const std::string kWARN_UNUSED_CLI_KEY = "warnUnusedCli";
 static const std::string kWARN_UNUSED_KEY = "warnUnused";
+static const std::string kWATCHED_DIRECTORIES_KEY = "watchedDirectories";
+static const std::string kWATCHED_FILES_KEY = "watchedFiles";
 
 static const std::string kSTART_MAGIC = "[== CMake Server ==[";
 static const std::string kEND_MAGIC = "]== CMake Server ==]";

Source/cmServerProtocol.cxx

@@ -391,6 +391,9 @@ const cmServerResponse cmServerProtocol1_0::Process(
   if (request.Type == kCONFIGURE_TYPE) {
     return this->ProcessConfigure(request);
   }
+  if (request.Type == kFILESYSTEM_WATCHERS_TYPE) {
+    return this->ProcessFileSystemWatchers(request);
+  }
   if (request.Type == kGLOBAL_SETTINGS_TYPE) {
     return this->ProcessGlobalSettings(request);
   }
@@ -1019,3 +1022,22 @@ cmServerResponse cmServerProtocol1_0::ProcessSetGlobalSettings(
 
   return request.Reply(Json::Value());
 }
+
+cmServerResponse cmServerProtocol1_0::ProcessFileSystemWatchers(
+  const cmServerRequest& request)
+{
+  const cmFileMonitor* const fm = FileMonitor();
+  Json::Value result = Json::objectValue;
+  Json::Value files = Json::arrayValue;
+  for (const auto& f : fm->WatchedFiles()) {
+    files.append(f);
+  }
+  Json::Value directories = Json::arrayValue;
+  for (const auto& d : fm->WatchedDirectories()) {
+    directories.append(d);
+  }
+  result[kWATCHED_FILES_KEY] = files;
+  result[kWATCHED_DIRECTORIES_KEY] = directories;
+
+  return request.Reply(result);
+}

Source/cmServerProtocol.h

@@ -117,6 +117,7 @@ private:
   cmServerResponse ProcessConfigure(const cmServerRequest& request);
   cmServerResponse ProcessGlobalSettings(const cmServerRequest& request);
   cmServerResponse ProcessSetGlobalSettings(const cmServerRequest& request);
+  cmServerResponse ProcessFileSystemWatchers(const cmServerRequest& request);
 
   enum State
   {