* fhandler_tty.cc (fhandler_tty_slave::read): Attempt #527 to properly

implement VMIN/VTIME.

diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index 0915a9e..497df69 100644 (file)
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,8 @@
+2002-10-16  Christopher Faylor  <cgf@redhat.com>
+
+       * fhandler_tty.cc (fhandler_tty_slave::read): Attempt #527 to properly
+       implement VMIN/VTIME.
+
 2002-10-15  Christopher Faylor  <cgf@redhat.com>
 
        * shared.cc (open_shared): Revert to "old" method for shared memory

diff --git a/winsup/cygwin/fhandler_tty.cc b/winsup/cygwin/fhandler_tty.cc
index a8d6df2..c8b73d7 100644 (file)
--- a/winsup/cygwin/fhandler_tty.cc
+++ b/winsup/cygwin/fhandler_tty.cc
@@ -632,9 +632,8 @@ fhandler_tty_slave::write (const void *ptr, size_t len)
 int __stdcall
 fhandler_tty_slave::read (void *ptr, size_t len)
 {
-  DWORD n;
   int totalread = 0;
-  int vmin = INT_MAX;
+  int vmin = 0;
   int vtime = 0;       /* Initialized to prevent -Wuninitialized warning */
   size_t readlen;
   DWORD bytes_in_pipe;
@@ -646,7 +645,9 @@ fhandler_tty_slave::read (void *ptr, size_t len)
 
   termios_printf ("read(%x, %d) handle %p", ptr, len, get_handle ());
 
-  if (!(get_ttyp ()->ti.c_lflag & ICANON))
+  if ((get_ttyp ()->ti.c_lflag & ICANON))
+    time_to_wait = INFINITE;
+  else
     {
       vmin = get_ttyp ()->ti.c_cc[VMIN];
       if (vmin > INP_BUFFER_SIZE)
@@ -656,17 +657,29 @@ fhandler_tty_slave::read (void *ptr, size_t len)
        vmin = 0;
       if (vtime < 0)
        vtime = 0;
-      time_to_wait = vtime == 0 ? INFINITE : 100 * vtime;
+      if (!vmin && !vtime)
+       time_to_wait = 0;
+      else
+       time_to_wait = !vtime ? INFINITE : 100 * vtime;
     }
-  else
-    time_to_wait = INFINITE;
 
   w4[0] = signal_arrived;
   w4[1] = input_available_event;
 
+  DWORD waiter = INFINITE;
   while (len)
     {
-      rc = WaitForMultipleObjects (2, w4, FALSE, time_to_wait);
+      rc = WaitForMultipleObjects (2, w4, FALSE, waiter);
+
+      if (rc == WAIT_TIMEOUT)
+       break;
+
+      if (rc == WAIT_FAILED)
+       {
+         termios_printf ("wait for input event failed, %E");
+         break;
+       }
+
       if (rc == WAIT_OBJECT_0)
        {
          /* if we've received signal after successfully reading some data,
@@ -676,13 +689,7 @@ fhandler_tty_slave::read (void *ptr, size_t len)
          set_sig_errno (EINTR);
          return -1;
        }
-      else if (rc == WAIT_FAILED)
-       {
-         termios_printf ("wait for input event failed, %E");
-         break;
-       }
-      else if (rc == WAIT_TIMEOUT)
-       break;
+
       rc = WaitForSingleObject (input_mutex, 1000);
       if (rc == WAIT_FAILED)
        {
@@ -700,7 +707,19 @@ fhandler_tty_slave::read (void *ptr, size_t len)
          _raise (SIGHUP);
          bytes_in_pipe = 0;
        }
+
+      if (!vmin && !time_to_wait)
+       {
+         ReleaseMutex (input_mutex);
+         return bytes_in_pipe;
+       }
+
       readlen = min (bytes_in_pipe, min (len, sizeof (buf)));
+
+      if (vmin && readlen > (unsigned) vmin)
+       readlen = vmin;
+
+      DWORD n = 0;
       if (readlen)
        {
          termios_printf ("reading %d bytes (vtime %d)", readlen, vtime);
@@ -746,7 +765,7 @@ fhandler_tty_slave::read (void *ptr, size_t len)
        }
       if (get_ttyp ()->ti.c_lflag & ICANON || is_nonblocking ())
        break;
-      if (totalread >= vmin && (vmin > 0 || totalread > 0))
+      if (vmin && totalread >= vmin)
        break;
 
       /* vmin == 0 && vtime == 0:
@@ -766,6 +785,9 @@ fhandler_tty_slave::read (void *ptr, size_t len)
 
       if (vmin == 0)
        break;
+
+      if (n)
+       waiter = time_to_wait;
     }
   termios_printf ("%d=read(%x, %d)", totalread, ptr, len);
   return totalread;