Cygwin: pty: Discard input already accepted on interrupt.

- Currently, input already accepted is not discarded on interrupt
  by VINTR, VQUIT and VSUSP keys. This patch fixes the issue.

diff --git a/winsup/cygwin/fhandler.h b/winsup/cygwin/fhandler.h
index 9b85d1ee93b7284ab4d9e67822225620ba213e98..4da35b7f5274668796a67de4aed7781b706072ac 100644 (file)
--- a/winsup/cygwin/fhandler.h
+++ b/winsup/cygwin/fhandler.h
@@ -1921,6 +1921,7 @@ class fhandler_termios: public fhandler_base
   int eat_readahead (int n);
   virtual void acquire_input_mutex_if_necessary (DWORD ms) {};
   virtual void release_input_mutex_if_necessary (void) {};
+  virtual void discard_input () {};
 
  public:
   tty_min*& tc () {return _tc;}
@@ -2451,6 +2452,7 @@ public:
   void fixup_after_exec ();
   int tcgetpgrp ();
   void flush_to_slave ();
+  void discard_input ();
 
   fhandler_pty_master (void *) {}
 

diff --git a/winsup/cygwin/fhandler_termios.cc b/winsup/cygwin/fhandler_termios.cc
index ae35fe8948721b4f784dd726c4cb32a49bd15b95..b487acab384d371cc596d80ae0447f1131819add 100644 (file)
--- a/winsup/cygwin/fhandler_termios.cc
+++ b/winsup/cygwin/fhandler_termios.cc
@@ -333,7 +333,10 @@ fhandler_termios::line_edit (const char *rptr, size_t nread, termios& ti,
 
          termios_printf ("got interrupt %d, sending signal %d", c, sig);
          if (!(ti.c_lflag & NOFLSH))
-           eat_readahead (-1);
+           {
+             eat_readahead (-1);
+             discard_input ();
+           }
          release_input_mutex_if_necessary ();
          tc ()->kill_pgrp (sig);
          acquire_input_mutex_if_necessary (INFINITE);

diff --git a/winsup/cygwin/fhandler_tty.cc b/winsup/cygwin/fhandler_tty.cc
index 930501d01c3bed7179254f0012bb6c96526cfe0b..244147a808d3e228a08778527dc9af8b9211412d 100644 (file)
--- a/winsup/cygwin/fhandler_tty.cc
+++ b/winsup/cygwin/fhandler_tty.cc
@@ -391,6 +391,21 @@ fhandler_pty_master::flush_to_slave ()
     accept_input ();
 }
 
+void
+fhandler_pty_master::discard_input ()
+{
+  DWORD bytes_in_pipe;
+  char buf[1024];
+  DWORD n;
+
+  WaitForSingleObject (input_mutex, INFINITE);
+  while (::bytes_available (bytes_in_pipe, from_master_cyg) && bytes_in_pipe)
+    ReadFile (from_master_cyg, buf, sizeof(buf), &n, NULL);
+  ResetEvent (input_available_event);
+  get_ttyp ()->discard_input = true;
+  ReleaseMutex (input_mutex);
+}
+
 DWORD
 fhandler_pty_common::__acquire_output_mutex (const char *fn, int ln,
                                             DWORD ms)
@@ -2150,6 +2165,9 @@ fhandler_pty_master::write (const void *ptr, size_t len)
        }
 
       WaitForSingleObject (input_mutex, INFINITE);
+      if ((ti.c_lflag & ISIG) && !(ti.c_iflag & IGNBRK)
+         && !(ti.c_lflag & NOFLSH) && memchr (buf, '\003', nlen))
+       get_ttyp ()->discard_input = true;
       DWORD n;
       WriteFile (to_slave, buf, nlen, &n, NULL);
       ReleaseMutex (input_mutex);
@@ -3709,6 +3727,8 @@ fhandler_pty_slave::transfer_input (tty::xfer_dir dir, HANDLE from, tty *ttyp,
       while (PeekConsoleInputA (from, r, INREC_SIZE, &n) && n)
        {
          ReadConsoleInputA (from, r, n, &n);
+         if (ttyp->discard_input)
+           continue;
          int len = 0;
          char *ptr = buf;
          for (DWORD i = 0; i < n; i++)
@@ -3773,6 +3793,8 @@ fhandler_pty_slave::transfer_input (tty::xfer_dir dir, HANDLE from, tty *ttyp,
        {
          DWORD n = MIN (bytes_in_pipe, NT_MAX_PATH);
          ReadFile (from, buf, n, &n, NULL);
+         if (ttyp->discard_input)
+           continue;
          char *ptr = buf;
          if (dir == tty::to_nat)
            {
@@ -3803,4 +3825,5 @@ fhandler_pty_slave::transfer_input (tty::xfer_dir dir, HANDLE from, tty *ttyp,
   else if (transfered)
     SetEvent (input_available_event);
   ttyp->pcon_input_state = dir;
+  ttyp->discard_input = false;
 }

diff --git a/winsup/cygwin/tty.cc b/winsup/cygwin/tty.cc
index eaab573e0f12f15e70979dae81dcedb97d9d117a..3c016315cdedb1dcca44cb3f3f96b87fd0b90a97 100644 (file)
--- a/winsup/cygwin/tty.cc
+++ b/winsup/cygwin/tty.cc
@@ -253,6 +253,7 @@ tty::init ()
   pcon_input_state = to_cyg;
   last_sig = 0;
   mask_flusho = false;
+  discard_input = false;
 }
 
 HANDLE

diff --git a/winsup/cygwin/tty.h b/winsup/cygwin/tty.h
index b74120416ab3990d09d1ca5a9e5c6e93876f44a4..f041250a394d55a87c21dcd93f8dd17570e7015f 100644 (file)
--- a/winsup/cygwin/tty.h
+++ b/winsup/cygwin/tty.h
@@ -131,6 +131,7 @@ private:
   bool req_xfer_input;
   xfer_dir pcon_input_state;
   bool mask_flusho;
+  bool discard_input;
 
 public:
   HANDLE from_master () const { return _from_master; }