StdLib: Implement da_ConFlush() and flush I/O buffers when closing a console device.

Add header file Efi/SysEfi.h
Clean up some indent issues.
Implement function da_ConFlush()
Modify da_ConClose() to flush its buffers and clean up better upon close.
Construct the console instance using the new da_ConFlush() instead of the nullop function.
Remove da_ConFlush() from the "Not implemented (yet?)" place holder.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Daryl McDaniel <edk2-lists@mc2research.org>
Reviewed-by: Erik Bjorge <erik.c.bjorge@intel.com>


git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@19587 6f19259b-4bc3-4df7-8a09-765794883524

StdLib/LibC/Uefi/Devices/Console/daConsole.c

@@ -10,6 +10,7 @@
   The devices status as a wide device is indicatd by _S_IWTTY being set in
   f_iflags.
 
+  Copyright (c) 2016, Daryl McDaniel. All rights reserved.<BR>
   Copyright (c) 2010 - 2014, Intel Corporation. All rights reserved.<BR>
   This program and the accompanying materials are licensed and made available under
   the terms and conditions of the BSD License that accompanies this distribution.
@@ -37,6 +38,7 @@
 #include  <sys/fcntl.h>
 #include  <unistd.h>
 #include  <sys/termios.h>
+#include  <Efi/SysEfi.h>
 #include  <kfile.h>
 #include  <Device/Device.h>
 #include  <Device/IIO.h>
@@ -104,6 +106,65 @@ WideTtyCvt( CHAR16 *dest, const char *buf, ssize_t n, mbstate_t *Cs)
   return i;
 }
 
+/** Flush the console's IIO buffers.
+
+    Flush the IIO Input or Output buffers depending upon the mode
+    of the specified file.
+
+    If the console is open for output, write any unwritten data in the output
+    buffer to the console.
+
+    If the console is open for input or output, discard any remaining data
+    in the associated buffers.
+
+    @param[in]    filp    Pointer to the target file's descriptor structure.
+
+    @retval     0     Always succeeds
+**/
+static
+int
+EFIAPI
+da_ConFlush(
+  struct __filedes *filp
+)
+{
+  cIIO       *This;
+  char       *MbcsPtr;
+  ssize_t     NumProc;
+  void       *OutPtr;
+
+  This = filp->devdata;
+
+  if (filp->f_iflags & S_ACC_READ)  {     // Readable so flush the input buffer
+    This->InBuf->Flush(This->InBuf, UNICODE_STRING_MAX);
+  }
+  if (filp->f_iflags & S_ACC_WRITE)  {    // Writable so flush the output buffer
+    // At this point, the characters to write are in OutBuf
+    // First, linearize and consume the buffer
+    NumProc = OutBuf->Read(OutBuf, gMD->UString, UNICODE_STRING_MAX-1);
+    if (NumProc > 0) {  // Optimization -- Nothing to do if no characters
+      gMD->UString[NumProc] = 0;   // Ensure that the buffer is terminated
+
+      if(filp->f_iflags & _S_IWTTY) {
+        // Output device expects wide characters, Output what we have
+        OutPtr = gMD->UString;
+      }
+      else {
+        // Output device expects narrow characters, convert to MBCS
+        OutPtr = gMD->UString2;
+        // Translate the wide buffer, gMD->UString into MBCS
+        // in the buffer pointed to by OutPtr.
+        // The returned value, NumProc, is the resulting number of bytes.
+        NumProc = wcstombs((char *)OutPtr, (const wchar_t *)gMD->UString, NumProc);
+        ((char *)OutPtr)[NumProc] = 0;   // Ensure the buffer is terminated
+      }
+      // Do the actual write of the data
+      (void) filp->f_ops->fo_write(filp, NULL, NumProc, OutPtr);
+    }
+  }
+  return 0;
+}
+
 /** Close an open file.
 
     @param[in]  filp    Pointer to the file descriptor structure for this file.
@@ -127,6 +188,13 @@ da_ConClose(
     EFIerrno = RETURN_INVALID_PARAMETER;
     return -1;    // Looks like a bad File Descriptor pointer
   }
+  // Stream and filp look OK, so continue.
+  // Flush the I/O buffers
+  (void) da_ConFlush(filp);
+
+  // Break the connection to IIO
+  filp->devdata = NULL;
+
   gMD->StdIo[Stream->InstanceNum] = NULL;   // Mark the stream as closed
   return 0;
 }
@@ -684,7 +752,7 @@ __Cons_construct(
         Stream->Abstraction.fo_fcntl    = &fnullop_fcntl;
         Stream->Abstraction.fo_ioctl    = &da_ConIoctl;
         Stream->Abstraction.fo_poll     = &da_ConPoll;
-    Stream->Abstraction.fo_flush    = &fnullop_flush;
+        Stream->Abstraction.fo_flush    = &da_ConFlush;
         Stream->Abstraction.fo_delete   = &fbadop_delete;
         Stream->Abstraction.fo_mkdir    = &fbadop_mkdir;
         Stream->Abstraction.fo_rmdir    = &fbadop_rmdir;
@@ -752,14 +820,4 @@ da_ConCntl(
   )
 {
 }
-
-static
-int
-EFIAPI
-da_ConFlush(
-  struct __filedes *filp
-  )
-{
-  return 0;
-}
 #endif  /* Not implemented for Console */