From c20a0325f3cc44ad6dd3eb386604e65db7e42267 Mon Sep 17 00:00:00 2001
From: "Michael J. Spencer" <bigcheesegs@gmail.com>
Date: Fri, 3 Dec 2010 17:54:07 +0000
Subject: [PATCH] Support/FileSystem: Add resize_file implementation.

llvm-svn: 120819
---
 llvm/lib/Support/Unix/PathV2.inc    | 10 ++++++++++
 llvm/lib/Support/Windows/PathV2.inc | 19 +++++++++++++++++++
 2 files changed, 29 insertions(+)

diff --git a/llvm/lib/Support/Unix/PathV2.inc b/llvm/lib/Support/Unix/PathV2.inc
index 8ecf2a4222d5..75cfce822a1f 100644
--- a/llvm/lib/Support/Unix/PathV2.inc
+++ b/llvm/lib/Support/Unix/PathV2.inc
@@ -213,6 +213,16 @@ error_code rename(const Twine &from, const Twine &to) {
   return make_error_code(errc::success);
 }
 
+error_code resize_file(const Twine &path, uint64_t size) {
+  SmallString<128> path_storage;
+  StringRef p = path.toNullTerminatedStringRef(path_storage);
+
+  if (::truncate(p.begin(), size) == -1)
+    return error_code(errno, system_category());
+
+  return make_error_code(errc::success);
+}
+
 error_code exists(const Twine &path, bool &result) {
   SmallString<128> path_storage;
   StringRef p = path.toNullTerminatedStringRef(path_storage);
diff --git a/llvm/lib/Support/Windows/PathV2.inc b/llvm/lib/Support/Windows/PathV2.inc
index c97ba5df5935..e98150713bb1 100644
--- a/llvm/lib/Support/Windows/PathV2.inc
+++ b/llvm/lib/Support/Windows/PathV2.inc
@@ -18,7 +18,10 @@
 
 #include "Windows.h"
 #include <WinCrypt.h>
+#include <fcntl.h>
 #include <io.h>
+#include <sys/stat.h>
+#include <sys/types.h>
 
 using namespace llvm;
 
@@ -290,6 +293,22 @@ error_code rename(const Twine &from, const Twine &to) {
   return make_error_code(errc::success);
 }
 
+error_code resize_file(const Twine &path, uint64_t size) {
+  SmallString<128> path_storage;
+  SmallVector<wchar_t, 128> path_utf16;
+
+  if (error_code ec = UTF8ToUTF16(path.toStringRef(path_storage),
+                                  path_utf16))
+    return ec;
+
+  int fd = ::_wopen(path_utf16.begin(), O_BINARY, S_IREAD | S_IWRITE);
+  if (fd == -1)
+    return error_code(errno, generic_category());
+  errno_t error = ::_chsize_s(fd, size);
+  ::close(fd);
+  return error_code(error, generic_category());
+}
+
 error_code exists(const Twine &path, bool &result) {
   SmallString<128> path_storage;
   SmallVector<wchar_t, 128> path_utf16;