Merge pull request #60 from scdwyer/master

Added support for gcs -speech option in OS X

sw/ground_segment/cockpit/speech.ml

@@ -1,5 +1,38 @@
 let active = ref false
 
+let current_os = ref "not_set"
+
+(* These two functions are from sw/lib/defivybus.ml *)
+let read_process_output command =
+  let buffer_size = 2048 in
+  let buffer = Buffer.create buffer_size in
+  let string = String.create buffer_size in
+  let in_channel = Unix.open_process_in command in
+  let chars_read = ref 1 in
+  while !chars_read <> 0 do
+    chars_read := input in_channel string 0 buffer_size;
+    Buffer.add_substring buffer string 0 !chars_read
+  done;
+  ignore (Unix.close_process_in in_channel);
+  Buffer.contents buffer
+
+let contains s substring =
+  try ignore (Str.search_forward (Str.regexp_string substring) s 0); true
+    with Not_found -> false
+      
 let say = fun s ->
-  if !active then
-    ignore (Sys.command (Printf.sprintf "spd-say '%s'&" s))
+  (
+  if !active then (
+   (* Checks if the os is known and gets the uname if not *)
+   if contains !current_os "not_set" then (
+      current_os := read_process_output "uname";
+    );
+    (* If the os is Darwin, then use "say" *)
+    if contains !current_os "Darwin" then (
+      ignore (Sys.command (Printf.sprintf "say '%s'&" s));
+    )
+    (* If the os is anything else, use "spd-say" (add additional cases here if necessary) *)
+    else (
+      ignore (Sys.command (Printf.sprintf "spd-say '%s'&" s));
+    )
+  ));;