From c97c9aa1e36087b87e23d6ec408dfb4923e3c5fc Mon Sep 17 00:00:00 2001
From: Frank Groeneveld <frank@frankgroeneveld.nl>
Date: Thu, 22 Jan 2015 21:53:08 +0100
Subject: [PATCH] Add OpenBSD support.

Re-uses most of the Mac OS X changes, but adds a read(2)/write(2) loop instead
of sendfile(2) when renaming across devices, because OpenBSD doesn't have
sendfile(2).
---
 CONTRIBUTORS       |  1 +
 file.cc            | 15 +++++++++++++--
 unbuffered_file.cc |  4 ++--
 3 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/CONTRIBUTORS b/CONTRIBUTORS
index b088c49..5618ed7 100644
--- a/CONTRIBUTORS
+++ b/CONTRIBUTORS
@@ -14,6 +14,7 @@ Code contributions:
   Igor Katson <igor.katson@gmail.com>
   Eugene Agafonov <e.a.agafonov@gmail.com>
   Antonia Stevens <a@antevens.com>
+  Frank Groeneveld <frank@frankgroeneveld.nl>
 
 Feel free to add yourself to this list in your pull-request.
 Please modify this file instead of source headers.
diff --git a/file.cc b/file.cc
index 5d4d141..972215f 100644
--- a/file.cc
+++ b/file.cc
@@ -6,7 +6,7 @@
 #include <unistd.h>
 #include <cerrno>
 #include <cstring>
-#ifdef __APPLE__
+#if defined( __APPLE__ ) || defined( __OpenBSD__ )
   #include <sys/socket.h>
 #else
   #include <sys/sendfile.h>
@@ -65,9 +65,20 @@ void File::rename( std::string const & from,
        source file. */
       write_fd = ::open( to.c_str(), O_WRONLY | O_CREAT, stat_buf.st_mode );
       /* Blast the bytes from one file to the other. */
-      #ifdef __APPLE__
+      #if defined( __APPLE__ )
       if ( -1 == sendfile(write_fd, read_fd, offset, &stat_buf.st_size, NULL, 0) )
          throw exCantRename( from + " to " + to );
+      #elif defined( __OpenBSD__ )
+
+      size_t BUFSIZE = 4096, size;
+      char buf[BUFSIZE];
+
+      while ( ( size = ::read( read_fd, buf, BUFSIZE ) ) != -1 && size != 0 )
+        ::write( write_fd, buf, size );
+
+      if ( size == -1 )
+         throw exCantRename( from + " to " + to );
+
       #else
       if ( -1 == sendfile(write_fd, read_fd, &offset, stat_buf.st_size) )
          throw exCantRename( from + " to " + to );
diff --git a/unbuffered_file.cc b/unbuffered_file.cc
index 0816e4a..1339480 100644
--- a/unbuffered_file.cc
+++ b/unbuffered_file.cc
@@ -13,7 +13,7 @@
 #include "unbuffered_file.hh"
 
 
-#ifdef __APPLE__
+#if defined( __APPLE__ ) || defined( __OpenBSD__ )
 #define lseek64 lseek
 #endif
 
@@ -24,7 +24,7 @@ UnbufferedFile::UnbufferedFile( char const * fileName, Mode mode )
 
   int flags = ( mode == WriteOnly ? ( O_WRONLY | O_CREAT | O_TRUNC ) :
                                     O_RDONLY );
-#ifndef __APPLE__
+#if !defined( __APPLE__ ) && !defined( __OpenBSD__ )
   flags |= O_LARGEFILE;
 #endif
   fd = open( fileName, flags, 0666 );