From a467e6bfede2fa3094b1e6c18cab21451b96aa54 Mon Sep 17 00:00:00 2001
From: Thayne McCombs <astrothayne@gmail.com>
Date: Fri, 9 Dec 2016 00:38:34 -0700
Subject: [PATCH] Add methods for compacting ranges.

---
 src/db.rs       | 27 +++++++++++++++++++++++++++
 src/ffi_util.rs |  8 ++++++++
 2 files changed, 35 insertions(+)

diff --git a/src/db.rs b/src/db.rs
index 7dcfb0c..b963440 100644
--- a/src/db.rs
+++ b/src/db.rs
@@ -16,6 +16,7 @@
 
 use {DB, Error, Options, WriteOptions};
 use ffi;
+use ffi_util::opt_bytes_to_ptr;
 
 use libc::{self, c_char, c_int, c_uchar, c_void, size_t};
 use std::collections::BTreeMap;
@@ -674,6 +675,32 @@ impl DB {
                      -> Result<(), Error> {
         self.delete_cf_opt(cf, key, &WriteOptions::default())
     }
+
+    pub fn compact_range(&self,
+                         start: Option<&[u8]>,
+                         end: Option<&[u8]>) {
+        unsafe {
+            ffi::rocksdb_compact_range(self.inner,
+                                       opt_bytes_to_ptr(start),
+                                       start.map_or(0, |s| s.len()) as size_t,
+                                       opt_bytes_to_ptr(end),
+                                       end.map_or(0, |e| e.len()) as size_t);
+       }
+    }
+
+    pub fn compact_range_cf(&self,
+                            cf: *mut ffi::rocksdb_column_family_handle_t,
+                            start: Option<&[u8]>,
+                            end: Option<&[u8]>) {
+        unsafe {
+            ffi::rocksdb_compact_range_cf(self.inner,
+                                          cf,
+                                          opt_bytes_to_ptr(start),
+                                          start.map_or(0, |s| s.len()) as size_t,
+                                          opt_bytes_to_ptr(end),
+                                          end.map_or(0, |e| e.len()) as size_t);
+       }
+    }
 }
 
 impl WriteBatch {
diff --git a/src/ffi_util.rs b/src/ffi_util.rs
index 9256845..e7a1790 100644
--- a/src/ffi_util.rs
+++ b/src/ffi_util.rs
@@ -15,6 +15,7 @@
 
 use libc::{self, c_char, c_void};
 use std::ffi::CStr;
+use std::ptr;
 
 pub fn error_message(ptr: *const c_char) -> String {
     let cstr = unsafe { CStr::from_ptr(ptr as *const _) };
@@ -25,6 +26,13 @@ pub fn error_message(ptr: *const c_char) -> String {
     s
 }
 
+pub fn opt_bytes_to_ptr(opt: Option<&[u8]>) -> *const c_char {
+    match opt {
+        Some(v) => v.as_ptr() as *const c_char,
+        None => ptr::null()
+    }
+}
+
 macro_rules! ffi_try {
     ( $($function:ident)::*( $( $arg:expr ),* ) ) => ({
         let mut err: *mut ::libc::c_char = ::std::ptr::null_mut();