From 1f289095f908fddd64152c5686bec25eecbc66d6 Mon Sep 17 00:00:00 2001
From: Betsy McPhail <betsy.mcphail@kitware.com>
Date: Mon, 23 Mar 2015 16:32:12 -0400
Subject: [PATCH] file(LOCK): Close file descriptor/handle when releasing a
 lock

The file lock functionality added in commit v3.2.0-rc1~297^2~1 (file:
Add LOCK subcommand to do file and directory locking, 2014-11-26) forgot
to close the lock file descriptors.  Eventually it was possible to run
out of file descriptors and locks could not longer be acquired.  Fix
this by closing the file descriptor or handle when we are done with it.
Also set the member back to the initial value from the constructor
to leave everything in a consistent state (useful for debugging).

Co-Author: Ruslan Baratov <ruslan_baratov@yahoo.com>
---
 Source/cmFileLockUnix.cxx  | 4 ++++
 Source/cmFileLockWin32.cxx | 3 +++
 2 files changed, 7 insertions(+)

diff --git a/Source/cmFileLockUnix.cxx b/Source/cmFileLockUnix.cxx
index fc18a64da..36a2d7288 100644
--- a/Source/cmFileLockUnix.cxx
+++ b/Source/cmFileLockUnix.cxx
@@ -15,6 +15,7 @@
 #include <errno.h> // errno
 #include <stdio.h> // SEEK_SET
 #include <fcntl.h>
+#include <unistd.h>
 #include "cmSystemTools.h"
 
 cmFileLock::cmFileLock(): File(-1)
@@ -31,6 +32,9 @@ cmFileLockResult cmFileLock::Release()
 
   this->Filename = "";
 
+  ::close(this->File);
+  this->File = -1;
+
   if (lockResult == 0)
     {
     return cmFileLockResult::MakeOk();
diff --git a/Source/cmFileLockWin32.cxx b/Source/cmFileLockWin32.cxx
index 469168985..dc65948bd 100644
--- a/Source/cmFileLockWin32.cxx
+++ b/Source/cmFileLockWin32.cxx
@@ -38,6 +38,9 @@ cmFileLockResult cmFileLock::Release()
 
   this->Filename = "";
 
+  CloseHandle(this->File);
+  this->File = INVALID_HANDLE_VALUE;
+
   if (unlockResult)
     {
     return cmFileLockResult::MakeOk();