From 2a7ab0f805883a08a54aa229ac15cd446d5fe10a Mon Sep 17 00:00:00 2001
From: Richard Dodd <richard.o.dodd@gmail.com>
Date: Tue, 25 Jul 2017 12:36:31 +0100
Subject: [PATCH] Include change from 5.4.5

Change "use_direct_writes" to "use_direct_io_for_flush_and_compaction"
---
 librocksdb-sys/src/lib.rs |  3 +-
 src/db_options.rs         | 64 ++++++++++++++++++++++++++++++++++++++-
 2 files changed, 65 insertions(+), 2 deletions(-)

diff --git a/librocksdb-sys/src/lib.rs b/librocksdb-sys/src/lib.rs
index 7cd922a..f2320ac 100644
--- a/librocksdb-sys/src/lib.rs
+++ b/librocksdb-sys/src/lib.rs
@@ -636,7 +636,8 @@ extern "C" {
                                                                v: c_uchar);
 
     pub fn rocksdb_options_set_use_direct_reads(opt: *mut rocksdb_options_t, v: c_uchar);
-    pub fn rocksdb_options_set_use_direct_writes(opt: *mut rocksdb_options_t, v: c_uchar);
+    pub fn rocksdb_options_set_use_direct_io_for_flush_and_compaction(opt: *mut rocksdb_options_t,
+                                                                      v: c_uchar);
 
     pub fn rocksdb_options_set_allow_mmap_reads(opt: *mut rocksdb_options_t, v: c_uchar);
 
diff --git a/src/db_options.rs b/src/db_options.rs
index 515af19..11a0b1a 100644
--- a/src/db_options.rs
+++ b/src/db_options.rs
@@ -388,17 +388,79 @@ impl Options {
     /// # Example
     ///
     /// ```
+    /// #[allow(deprecated)]
     /// use rocksdb::Options;
     ///
     /// let mut opts = Options::default();
     /// opts.set_use_direct_writes(true);
     /// ```
+    #[deprecated(note = "replaced by `Options::set_use_direct_io_for_flush_and_compaction`")]
     pub fn set_use_direct_writes(&mut self, enabled: bool) {
         unsafe {
-            ffi::rocksdb_options_set_use_direct_writes(self.inner, enabled as c_uchar);
+            ffi::rocksdb_options_set_use_direct_io_for_flush_and_compaction(self.inner,
+                                                                            enabled as c_uchar);
         }
     }
 
+    /// Enable direct I/O mode for writing
+    /// they may or may not improve performance depending on the use case
+    ///
+    /// Files will be opened in "direct I/O" mode
+    /// which means that data written to the disk will not be cached or
+    /// buffered. The hardware buffer of the devices may however still
+    /// be used. Memory mapped files are not impacted by these parameters.
+    ///
+    /// Default: false
+    ///
+    /// # Example
+    ///
+    /// ```
+    /// use rocksdb::Options;
+    ///
+    /// let mut opts = Options::default();
+    /// opts.set_use_direct_io_for_flush_and_compaction(true);
+    /// ```
+    pub fn set_use_direct_io_for_flush_and_compaction(&mut self, enabled: bool) {
+        unsafe {
+            ffi::rocksdb_options_set_use_direct_io_for_flush_and_compaction(self.inner,
+                                                                            enabled as c_uchar);
+        }
+    }
+
+    /// Hints to the OS that it should not buffer disk I/O. Enabling this
+    /// parameter may improve performance but increases pressure on the
+    /// system cache.
+    ///
+    /// The exact behavior of this parameter is platform dependent.
+    ///
+    /// On POSIX systems, after RocksDB reads data from disk it will
+    /// mark the pages as "unneeded". The operating system may - or may not
+    /// - evict these pages from memory, reducing pressure on the system
+    /// cache. If the disk block is requested again this can result in
+    /// additional disk I/O.
+    ///
+    /// On WINDOWS systems, files will be opened in "unbuffered I/O" mode
+    /// which means that data read from the disk will not be cached or
+    /// bufferized. The hardware buffer of the devices may however still
+    /// be used. Memory mapped files are not impacted by this parameter.
+    ///
+    /// Default: true
+    ///
+    /// # Example
+    ///
+    /// ```
+    /// #[allow(deprecated)]
+    /// use rocksdb::Options;
+    ///
+    /// let mut opts = Options::default();
+    /// opts.set_allow_os_buffer(false);
+    /// ```
+    #[deprecated(since="0.7.0", note="replaced with set_use_direct_reads/set_use_direct_io_for_flush_and_compaction methods")]
+    pub fn set_allow_os_buffer(&mut self, is_allow: bool) {
+        self.set_use_direct_reads(!is_allow);
+        self.set_use_direct_io_for_flush_and_compaction(!is_allow);
+    }
+
     /// Sets the number of shards used for table cache.
     ///
     /// Default: `6`