added winsz message to call TIOCSWINSZ on pty master

c_src/exec.cpp

@@ -285,8 +285,8 @@ bool process_command()
         return false;
     }
 
-    enum CmdTypeT        {  MANAGE,  RUN,  STOP,  KILL,  LIST,  SHUTDOWN,  STDIN,  DEBUG  } cmd;
-    const char* cmds[] = { "manage","run","stop","kill","list","shutdown","stdin","debug" };
+    enum CmdTypeT        {  MANAGE,  RUN,  STOP,  KILL,  LIST,  SHUTDOWN,  STDIN,  DEBUG, WINSZ  } cmd;
+    const char* cmds[] = { "manage","run","stop","kill","list","shutdown","stdin","debug", "winsz" };
 
     /* Determine the command */
     if ((int)(cmd = (CmdTypeT) eis.decodeAtomIndex(cmds, command)) < 0) {
@@ -395,6 +395,26 @@ bool process_command()
             send_pid_list(transId, children);
             break;
         }
+        case WINSZ: {
+            // {winsz, OsPid::integer(), rows::integer(), cols::integer()}
+            long pid, rows, cols;
+            if (arity != 4
+                || eis.decodeInt(pid) < 0
+                || eis.decodeInt(rows) < 0
+                || eis.decodeInt(cols) < 0) {
+                send_error_str(transId, true, "badarg");
+                break;
+            }
+            MapChildrenT::iterator it = children.find(pid);
+            if (it == children.end()) {
+                if (debug)
+                    fprintf(stderr, "pid %ld doesn't exist\r\n", pid);
+                break;
+            }
+            set_pid_winsz(it->second, rows, cols);
+            break;
+        }
+
         case STDIN: {
             // {stdin, OsPid::integer(), Data::binary()}
             long pid;

c_src/exec.hpp

@@ -151,6 +151,7 @@ int     read_sigchld(pid_t& child);
 void    check_child_exit(pid_t pid);
 int     set_nice(pid_t pid,int nice, std::string& error);
 bool    process_sigchld();
+bool    set_pid_winsz(CmdInfo& ci, int rows, int cols);
 bool    process_pid_input(CmdInfo& ci);
 void    process_pid_output(CmdInfo& ci, int maxsize = 4096);
 int     send_ok(int transId, long value = -1);

c_src/exec_impl.cpp

@@ -101,6 +101,21 @@ int set_nice(pid_t pid,int nice, std::string& error)
     return 0;
 }
 
+//------------------------------------------------------------------------------
+bool set_pid_winsz(CmdInfo& ci, int rows, int cols)
+{
+    int& fd = ci.stream_fd[STDIN_FILENO];
+    int r;
+    struct winsize ws;
+    ws.ws_row = rows;
+    ws.ws_col = cols;
+    r = ioctl(fd, TIOCSWINSZ, &ws);
+    if (debug)
+        fprintf(stderr, "TIOCSWINSZ rows=%d cols=%d ret=%d\n", rows, cols, r);
+
+    return true;
+}
+
 //------------------------------------------------------------------------------
 bool process_pid_input(CmdInfo& ci)
 {

src/exec.erl

@@ -42,7 +42,7 @@
 
 %% External exports
 -export([
-    start/0, start/1, start_link/1, run/2, run_link/2, manage/2, send/2,
+    start/0, start/1, start_link/1, run/2, run_link/2, manage/2, send/2, winsz/3,
     which_children/0, kill/2,       setpgid/2, stop/1, stop_and_wait/2,
     ospid/1, pid/1,   status/1,     signal/1,  debug/1
 ]).
@@ -467,6 +467,20 @@ send(OsPid, Data)
        (is_binary(Data)   orelse Data =:= eof) ->
     gen_server:call(?MODULE, {port, {send, OsPid, Data}}).
 
+%%-------------------------------------------------------------------------
+%% @doc Set the pty terminal `Rows' and `Cols' of the OS process identified by `OsPid'.
+%%
+%% The process must have been created with the `pty' option.
+%%
+%% @end
+%%-------------------------------------------------------------------------
+-spec winsz(OsPid :: ospid() | pid(), integer(), integer()) -> ok.
+winsz(OsPid, Rows, Cols)
+  when (is_integer(OsPid) orelse is_pid(OsPid)),
+       is_integer(Rows),
+       is_integer(Cols) ->
+    gen_server:call(?MODULE, {port, {winsz, OsPid, Rows, Cols}}).
+
 %%-------------------------------------------------------------------------
 %% @doc Set debug level of the port process.
 %% @end
@@ -986,6 +1000,15 @@ is_port_command({send, Pid, Data}, _Pid, _State)
 is_port_command({send, OsPid, Data}, _Pid, _State)
   when is_integer(OsPid), is_binary(Data) orelse Data =:= eof ->
     {ok, {stdin, OsPid, Data}};
+is_port_command({winsz, Pid, Rows, Cols}, _Pid, _State)
+  when is_pid(Pid), is_integer(Rows), is_integer(Cols) ->
+    case ets:lookup(exec_mon, Pid) of
+    [{Pid, OsPid}]  -> {ok, {winsz, OsPid, Rows, Cols}};
+    []              -> throw({error, no_process})
+    end;
+is_port_command({winsz, OsPid, Rows, Cols}, _Pid, _State)
+  when is_integer(OsPid), is_integer(Rows), is_integer(Cols) ->
+    {ok, {winsz, OsPid, Rows, Cols}};
 is_port_command({kill, OsPid, Sig}=T, _Pid, _State) when is_integer(OsPid),is_integer(Sig) -> 
     {ok, T, undefined, undefined, []};
 is_port_command({setpgid, OsPid, Gid}=T, _Pid, _State) when is_integer(OsPid),is_integer(Gid) -> 
@@ -1112,6 +1135,7 @@ exec_test_() ->
         [
             ?tt(test_monitor()),
             ?tt(test_sync()),
+            ?tt(test_winsz()),
             ?tt(test_stdin()),
             ?tt(test_stdin_eof()),
             ?tt(test_std(stdout)),
@@ -1140,6 +1164,14 @@ test_sync() ->
          exec:run(["/bin/echo", ""], [sync, stdout])).
 
 
+test_winsz() ->
+    {ok, P, I} = exec:run(["/bin/bash", "-i", "-c", "echo started; read x; echo LINES=$(tput lines) COLUMNS=$(tput cols)"], [stdin, stdout, stderr, monitor, pty]),
+    ?receiveMatch({stdout, I, <<"started\r\n">>}, 3000),
+    ok = exec:winsz(I, 99, 88),
+    ok = exec:send(I, <<"\n">>),
+    ?receiveMatch({stdout, I, <<"LINES=99 COLUMNS=88\r\n">>}, 3000),
+    ?receiveMatch({'DOWN', _, process, P, normal}, 5000).
+
 test_stdin() ->
     {ok, P, I} = exec:run("read x; echo \"Got: $x\"", [stdin, stdout, monitor]),
     ok = exec:send(I, <<"Test data\n">>),