merging benesch's work and more recent spacejam master

.travis.yml

@@ -10,8 +10,12 @@ addons:
   apt:
     sources:
       - ubuntu-toolchain-r-test
+      - llvm-toolchain-trusty
     packages:
       - g++-5
+      - llvm-3.9-dev
+      - libclang-3.9-dev
+      - clang-3.9
 
 script:
   - cargo test --manifest-path=librocksdb-sys/Cargo.toml

librocksdb-sys/Cargo.toml

@@ -24,3 +24,4 @@ const-cstr = "0.2"
 [build-dependencies]
 gcc = { version = "0.3", features = ["parallel"] }
 make-cmd = "0.1"
+bindgen = "0.29"

librocksdb-sys/build.rs

@@ -1,6 +1,9 @@
 extern crate gcc;
+extern crate bindgen;
 
+use std::env;
 use std::fs;
+use std::path::PathBuf;
 
 fn link(name: &str, bundled: bool) {
     use std::env::var;
@@ -30,7 +33,18 @@ fn build_rocksdb() {
     println!("cargo:rerun-if-changed=build.rs");
     println!("cargo:rerun-if-changed=rocksdb/");
 
-    let mut config = gcc::Config::new();
+    let bindings = bindgen::Builder::default()
+        .header("rocksdb/include/rocksdb/c.h")
+        .ctypes_prefix("libc")
+        .generate()
+        .expect("unable to generate rocksdb bindings");
+
+    let out_path = PathBuf::from(env::var("OUT_DIR").unwrap());
+    bindings
+        .write_to_file(out_path.join("bindings.rs"))
+        .expect("unable to write rocksdb bindings");
+
+    let mut config = gcc::Build::new();
     config.include("rocksdb/include/");
     config.include("rocksdb/");
     config.include("rocksdb/third-party/gtest-1.7.0/fused-src/");
@@ -115,7 +129,7 @@ fn build_rocksdb() {
 }
 
 fn build_snappy() {
-    let mut config = gcc::Config::new();
+    let mut config = gcc::Build::new();
     config.include("snappy/");
     config.include(".");
 

src/backup.rs

@@ -35,16 +35,19 @@ pub struct RestoreOptions {
 
 impl BackupEngine {
     /// Open a backup engine with the specified options.
-    pub fn open<P: AsRef<Path>>(opts: &BackupEngineOptions,
-                                path: P)
-                                -> Result<BackupEngine, Error> {
+    pub fn open<P: AsRef<Path>>(
+        opts: &BackupEngineOptions,
+        path: P,
+    ) -> Result<BackupEngine, Error> {
         let path = path.as_ref();
         let cpath = match CString::new(path.to_string_lossy().as_bytes()) {
             Ok(c) => c,
             Err(_) => {
-                return Err(Error::new("Failed to convert path to CString \
+                return Err(Error::new(
+                    "Failed to convert path to CString \
                                        when opening backup engine"
-                    .to_owned()))
+                        .to_owned(),
+                ))
             }
         };
 
@@ -60,15 +63,20 @@ impl BackupEngine {
 
     pub fn create_new_backup(&mut self, db: &DB) -> Result<(), Error> {
         unsafe {
-            ffi_try!(ffi::rocksdb_backup_engine_create_new_backup(self.inner, db.inner));
+            ffi_try!(ffi::rocksdb_backup_engine_create_new_backup(
+                self.inner,
+                db.inner,
+            ));
             Ok(())
         }
     }
 
     pub fn purge_old_backups(&mut self, num_backups_to_keep: usize) -> Result<(), Error> {
         unsafe {
-            ffi_try!(ffi::rocksdb_backup_engine_purge_old_backups(self.inner,
-                                                                  num_backups_to_keep as uint32_t));
+            ffi_try!(ffi::rocksdb_backup_engine_purge_old_backups(
+                self.inner,
+                num_backups_to_keep as uint32_t,
+            ));
             Ok(())
         }
     }

src/compaction_filter.rs

@@ -43,42 +43,48 @@ pub enum Decision {
 ///  [set_compaction_filter]: ../struct.Options.html#method.set_compaction_filter
 pub trait CompactionFilterFn: FnMut(u32, &[u8], &[u8]) -> Decision {}
 impl<F> CompactionFilterFn for F
-    where F: FnMut(u32, &[u8], &[u8]) -> Decision,
-          F: Send + 'static
+where
+    F: FnMut(u32, &[u8], &[u8]) -> Decision,
+    F: Send + 'static,
 {
 }
 
 pub struct CompactionFilterCallback<F>
-    where F: CompactionFilterFn
+where
+    F: CompactionFilterFn,
 {
     pub name: CString,
     pub filter_fn: F,
 }
 
 pub unsafe extern "C" fn destructor_callback<F>(raw_cb: *mut c_void)
-    where F: CompactionFilterFn
+where
+    F: CompactionFilterFn,
 {
     let _: Box<CompactionFilterCallback<F>> = mem::transmute(raw_cb);
 }
 
 pub unsafe extern "C" fn name_callback<F>(raw_cb: *mut c_void) -> *const c_char
-    where F: CompactionFilterFn
+where
+    F: CompactionFilterFn,
 {
     let cb = &*(raw_cb as *mut CompactionFilterCallback<F>);
     cb.name.as_ptr()
 }
 
-pub unsafe extern "C" fn filter_callback<F>(raw_cb: *mut c_void,
-                                            level: c_int,
-                                            raw_key: *const c_char,
-                                            key_length: size_t,
-                                            existing_value: *const c_char,
-                                            value_length: size_t,
-                                            new_value: *mut *mut c_char,
-                                            new_value_length: *mut size_t,
-                                            value_changed: *mut c_uchar)
-                                            -> c_uchar
-    where F: CompactionFilterFn
+pub unsafe extern "C" fn filter_callback<F>(
+    raw_cb: *mut c_void,
+    level: c_int,
+    raw_key: *const c_char,
+    key_length: size_t,
+    existing_value: *const c_char,
+    value_length: size_t,
+    new_value: *mut *mut c_char,
+    new_value_length: *mut size_t,
+    value_changed: *mut c_uchar,
+) -> c_uchar
+where
+    F: CompactionFilterFn,
 {
     use self::Decision::*;
 

src/comparator.rs

@@ -37,12 +37,13 @@ pub unsafe extern "C" fn name_callback(raw_cb: *mut c_void) -> *const c_char {
     ptr as *const c_char
 }
 
-pub unsafe extern "C" fn compare_callback(raw_cb: *mut c_void,
-                                          a_raw: *const c_char,
-                                          a_len: size_t,
-                                          b_raw: *const c_char,
-                                          b_len: size_t)
-                                          -> c_int {
+pub unsafe extern "C" fn compare_callback(
+    raw_cb: *mut c_void,
+    a_raw: *const c_char,
+    a_len: size_t,
+    b_raw: *const c_char,
+    b_len: size_t,
+) -> c_int {
     let cb: &mut ComparatorCallback = &mut *(raw_cb as *mut ComparatorCallback);
     let a: &[u8] = slice::from_raw_parts(a_raw as *const u8, a_len as usize);
     let b: &[u8] = slice::from_raw_parts(b_raw as *const u8, b_len as usize);

src/db.rs

@@ -55,10 +55,10 @@ pub enum DBCompactionStyle {
 
 #[derive(Debug, Copy, Clone, PartialEq)]
 pub enum DBRecoveryMode {
-    TolerateCorruptedTailRecords = ffi::rocksdb_recovery_mode_tolerate_corrupted_tail_records as isize,
-    AbsoluteConsistency = ffi::rocksdb_recovery_mode_absolute_consistency as isize,
-    PointInTime = ffi::rocksdb_recovery_mode_point_in_time as isize,
-    SkipAnyCorruptedRecord = ffi::rocksdb_recovery_mode_skip_any_corrupted_record as isize,
+    TolerateCorruptedTailRecords = ffi::rocksdb_tolerate_corrupted_tail_records_recovery as isize,
+    AbsoluteConsistency = ffi::rocksdb_absolute_consistency_recovery as isize,
+    PointInTime = ffi::rocksdb_point_in_time_recovery as isize,
+    SkipAnyCorruptedRecord = ffi::rocksdb_skip_any_corrupted_records_recovery as isize,
 }
 
 /// An atomic batch of write operations.
@@ -197,17 +197,14 @@ pub enum IteratorMode<'a> {
 
 impl DBRawIterator {
     fn new(db: &DB, readopts: &ReadOptions) -> DBRawIterator {
-        unsafe {
-            DBRawIterator {
-                inner: ffi::rocksdb_create_iterator(db.inner, readopts.inner),
-            }
-        }
+        unsafe { DBRawIterator { inner: ffi::rocksdb_create_iterator(db.inner, readopts.inner) } }
     }
 
-    fn new_cf(db: &DB,
-              cf_handle: ColumnFamily,
-              readopts: &ReadOptions)
-              -> Result<DBRawIterator, Error> {
+    fn new_cf(
+        db: &DB,
+        cf_handle: ColumnFamily,
+        readopts: &ReadOptions,
+    ) -> Result<DBRawIterator, Error> {
         unsafe {
             Ok(DBRawIterator {
                 inner: ffi::rocksdb_create_iterator_cf(db.inner, readopts.inner, cf_handle.inner),
@@ -251,7 +248,9 @@ impl DBRawIterator {
     /// }
     /// ```
     pub fn seek_to_first(&mut self) {
-        unsafe { ffi::rocksdb_iter_seek_to_first(self.inner); }
+        unsafe {
+            ffi::rocksdb_iter_seek_to_first(self.inner);
+        }
     }
 
     /// Seeks to the last key in the database.
@@ -285,7 +284,9 @@ impl DBRawIterator {
     /// }
     /// ```
     pub fn seek_to_last(&mut self) {
-        unsafe { ffi::rocksdb_iter_seek_to_last(self.inner); }
+        unsafe {
+            ffi::rocksdb_iter_seek_to_last(self.inner);
+        }
     }
 
     /// Seeks to the specified key or the first key that lexicographically follows it.
@@ -312,7 +313,13 @@ impl DBRawIterator {
     /// }
     /// ```
     pub fn seek(&mut self, key: &[u8]) {
-        unsafe { ffi::rocksdb_iter_seek(self.inner, key.as_ptr() as *const c_char, key.len() as size_t); }
+        unsafe {
+            ffi::rocksdb_iter_seek(
+                self.inner,
+                key.as_ptr() as *const c_char,
+                key.len() as size_t,
+            );
+        }
     }
 
     /// Seeks to the specified key, or the first key that lexicographically precedes it.
@@ -339,21 +346,31 @@ impl DBRawIterator {
     ///    // There are no keys in the database
     /// }
     pub fn seek_for_prev(&mut self, key: &[u8]) {
-        unsafe { ffi::rocksdb_iter_seek_for_prev(self.inner, key.as_ptr() as *const c_char, key.len() as size_t); }
+        unsafe {
+            ffi::rocksdb_iter_seek_for_prev(
+                self.inner,
+                key.as_ptr() as *const c_char,
+                key.len() as size_t,
+            );
+        }
     }
 
     /// Seeks to the next key.
     ///
     /// Returns true if the iterator is valid after this operation.
     pub fn next(&mut self) {
-        unsafe { ffi::rocksdb_iter_next(self.inner); }
+        unsafe {
+            ffi::rocksdb_iter_next(self.inner);
+        }
     }
 
     /// Seeks to the previous key.
     ///
     /// Returns true if the iterator is valid after this operation.
     pub fn prev(&mut self) {
-        unsafe { ffi::rocksdb_iter_prev(self.inner); }
+        unsafe {
+            ffi::rocksdb_iter_prev(self.inner);
+        }
     }
 
     /// Returns a slice to the internal buffer storing the current key.
@@ -377,9 +394,7 @@ impl DBRawIterator {
 
     /// Returns a copy of the current key.
     pub fn key(&self) -> Option<Vec<u8>> {
-        unsafe {
-            self.key_inner().map(|key| key.to_vec())
-        }
+        unsafe { self.key_inner().map(|key| key.to_vec()) }
     }
 
     /// Returns a slice to the internal buffer storing the current value.
@@ -403,9 +418,7 @@ impl DBRawIterator {
 
     /// Returns a copy of the current value.
     pub fn value(&self) -> Option<Vec<u8>> {
-        unsafe {
-            self.value_inner().map(|value| value.to_vec())
-        }
+        unsafe { self.value_inner().map(|value| value.to_vec()) }
     }
 }
 
@@ -428,11 +441,12 @@ impl DBIterator {
         rv
     }
 
-    fn new_cf(db: &DB,
-              cf_handle: ColumnFamily,
-              readopts: &ReadOptions,
-              mode: IteratorMode)
-              -> Result<DBIterator, Error> {
+    fn new_cf(
+        db: &DB,
+        cf_handle: ColumnFamily,
+        readopts: &ReadOptions,
+        mode: IteratorMode,
+    ) -> Result<DBIterator, Error> {
         let mut rv = DBIterator {
             raw: try!(DBRawIterator::new_cf(db, cf_handle, readopts)),
             direction: Direction::Forward, // blown away by set_mode()
@@ -484,7 +498,10 @@ impl Iterator for DBIterator {
 
         if self.raw.valid() {
             // .key() and .value() only ever return None if valid == false, which we've just cheked
-            Some((self.raw.key().unwrap().into_boxed_slice(), self.raw.value().unwrap().into_boxed_slice()))
+            Some((
+                self.raw.key().unwrap().into_boxed_slice(),
+                self.raw.value().unwrap().into_boxed_slice(),
+            ))
         } else {
             None
         }
@@ -512,10 +529,11 @@ impl<'a> Snapshot<'a> {
         DBIterator::new(self.db, &readopts, mode)
     }
 
-    pub fn iterator_cf(&self,
-                       cf_handle: ColumnFamily,
-                       mode: IteratorMode)
-                       -> Result<DBIterator, Error> {
+    pub fn iterator_cf(
+        &self,
+        cf_handle: ColumnFamily,
+        mode: IteratorMode,
+    ) -> Result<DBIterator, Error> {
         let mut readopts = ReadOptions::default();
         readopts.set_snapshot(self);
         DBIterator::new_cf(self.db, cf_handle, &readopts, mode)
@@ -527,9 +545,7 @@ impl<'a> Snapshot<'a> {
         DBRawIterator::new(self.db, &readopts)
     }
 
-    pub fn raw_iterator_cf(&self,
-                       cf_handle: ColumnFamily)
-                       -> Result<DBRawIterator, Error> {
+    pub fn raw_iterator_cf(&self, cf_handle: ColumnFamily) -> Result<DBRawIterator, Error> {
         let mut readopts = ReadOptions::default();
         readopts.set_snapshot(self);
         DBRawIterator::new_cf(self.db, cf_handle, &readopts)
@@ -541,10 +557,7 @@ impl<'a> Snapshot<'a> {
         self.db.get_opt(key, &readopts)
     }
 
-    pub fn get_cf(&self,
-                  cf: ColumnFamily,
-                  key: &[u8])
-                  -> Result<Option<DBVector>, Error> {
+    pub fn get_cf(&self, cf: ColumnFamily, key: &[u8]) -> Result<Option<DBVector>, Error> {
         let mut readopts = ReadOptions::default();
         readopts.set_snapshot(self);
         self.db.get_cf_opt(cf, key, &readopts)
@@ -584,16 +597,20 @@ impl DB {
         let cpath = match CString::new(path.to_string_lossy().as_bytes()) {
             Ok(c) => c,
             Err(_) => {
-                return Err(Error::new("Failed to convert path to CString \
+                return Err(Error::new(
+                    "Failed to convert path to CString \
                                        when opening DB."
-                    .to_owned()))
+                        .to_owned(),
+                ))
             }
         };
 
         if let Err(e) = fs::create_dir_all(&path) {
-            return Err(Error::new(format!("Failed to create RocksDB\
+            return Err(Error::new(format!(
+                "Failed to create RocksDB\
                                            directory: `{:?}`.",
-                                          e)));
+                e
+            )));
         }
 
         let db: *mut ffi::rocksdb_t;
@@ -612,34 +629,40 @@ impl DB {
 
             // We need to store our CStrings in an intermediate vector
             // so that their pointers remain valid.
-            let c_cfs: Vec<CString> = cfs_v.iter()
+            let c_cfs: Vec<CString> = cfs_v
+                .iter()
                 .map(|cf| CString::new(cf.as_bytes()).unwrap())
                 .collect();
 
-            let cfnames: Vec<_> = c_cfs.iter().map(|cf| cf.as_ptr()).collect();
+            let mut cfnames: Vec<_> = c_cfs.iter().map(|cf| cf.as_ptr()).collect();
 
             // These handles will be populated by DB.
             let mut cfhandles: Vec<_> = cfs_v.iter().map(|_| ptr::null_mut()).collect();
 
             // TODO(tyler) allow options to be passed in.
-            let cfopts: Vec<_> = cfs_v.iter()
+            let mut cfopts: Vec<_> = cfs_v
+                .iter()
                 .map(|_| unsafe { ffi::rocksdb_options_create() as *const _ })
                 .collect();
 
             unsafe {
-                db = ffi_try!(ffi::rocksdb_open_column_families(opts.inner,
-                                                                cpath.as_ptr() as *const _,
-                                                                cfs_v.len() as c_int,
-                                                                cfnames.as_ptr() as *const _,
-                                                                cfopts.as_ptr(),
-                                                                cfhandles.as_mut_ptr()));
+                db = ffi_try!(ffi::rocksdb_open_column_families(
+                    opts.inner,
+                    cpath.as_ptr(),
+                    cfs_v.len() as c_int,
+                    cfnames.as_mut_ptr(),
+                    cfopts.as_mut_ptr(),
+                    cfhandles.as_mut_ptr(),
+                ));
             }
 
             for handle in &cfhandles {
                 if handle.is_null() {
-                    return Err(Error::new("Received null column family \
+                    return Err(Error::new(
+                        "Received null column family \
                                            handle from DB."
-                        .to_owned()));
+                            .to_owned(),
+                    ));
                 }
             }
 
@@ -664,22 +687,27 @@ impl DB {
         let cpath = match CString::new(path.to_string_lossy().as_bytes()) {
             Ok(c) => c,
             Err(_) => {
-                return Err(Error::new("Failed to convert path to CString \
+                return Err(Error::new(
+                    "Failed to convert path to CString \
                                        when opening DB."
-                                      .to_owned()))
+                        .to_owned(),
+                ))
             }
         };
 
         let mut length = 0;
 
         unsafe {
-            let ptr = ffi_try!(ffi::rocksdb_list_column_families(opts.inner,
-                                                                 cpath.as_ptr() as *const _,
-                                                                 &mut length));
-
-            let vec = Vec::from_raw_parts(ptr, length, length).iter().map(|&ptr| {
-                CString::from_raw(ptr).into_string().unwrap()
-            }).collect();
+            let ptr = ffi_try!(ffi::rocksdb_list_column_families(
+                opts.inner,
+                cpath.as_ptr() as *const _,
+                &mut length,
+            ));
+
+            let vec = Vec::from_raw_parts(ptr, length, length)
+                .iter()
+                .map(|&ptr| CString::from_raw(ptr).into_string().unwrap())
+                .collect();
             Ok(vec)
         }
     }
@@ -724,21 +752,25 @@ impl DB {
 
     pub fn get_opt(&self, key: &[u8], readopts: &ReadOptions) -> Result<Option<DBVector>, Error> {
         if readopts.inner.is_null() {
-            return Err(Error::new("Unable to create RocksDB read options. \
+            return Err(Error::new(
+                "Unable to create RocksDB read options. \
                                    This is a fairly trivial call, and its \
                                    failure may be indicative of a \
                                    mis-compiled or mis-loaded RocksDB \
                                    library."
-                .to_owned()));
+                    .to_owned(),
+            ));
         }
 
         unsafe {
             let mut val_len: size_t = 0;
-            let val = ffi_try!(ffi::rocksdb_get(self.inner,
-                                                readopts.inner,
-                                                key.as_ptr() as *const c_char,
-                                                key.len() as size_t,
-                                                &mut val_len)) as *mut u8;
+            let val = ffi_try!(ffi::rocksdb_get(
+                self.inner,
+                readopts.inner,
+                key.as_ptr() as *const c_char,
+                key.len() as size_t,
+                &mut val_len,
+            )) as *mut u8;
             if val.is_null() {
                 Ok(None)
             } else {
@@ -752,28 +784,33 @@ impl DB {
         self.get_opt(key, &ReadOptions::default())
     }
 
-    pub fn get_cf_opt(&self,
-                      cf: ColumnFamily,
-                      key: &[u8],
-                      readopts: &ReadOptions)
-                      -> Result<Option<DBVector>, Error> {
+    pub fn get_cf_opt(
+        &self,
+        cf: ColumnFamily,
+        key: &[u8],
+        readopts: &ReadOptions,
+    ) -> Result<Option<DBVector>, Error> {
         if readopts.inner.is_null() {
-            return Err(Error::new("Unable to create RocksDB read options. \
+            return Err(Error::new(
+                "Unable to create RocksDB read options. \
                                    This is a fairly trivial call, and its \
                                    failure may be indicative of a \
                                    mis-compiled or mis-loaded RocksDB \
                                    library."
-                .to_owned()));
+                    .to_owned(),
+            ));
         }
 
         unsafe {
             let mut val_len: size_t = 0;
-            let val = ffi_try!(ffi::rocksdb_get_cf(self.inner,
-                                                   readopts.inner,
-                                                   cf.inner,
-                                                   key.as_ptr() as *const c_char,
-                                                   key.len() as size_t,
-                                                   &mut val_len)) as *mut u8;
+            let val = ffi_try!(ffi::rocksdb_get_cf(
+                self.inner,
+                readopts.inner,
+                cf.inner,
+                key.as_ptr() as *const c_char,
+                key.len() as size_t,
+                &mut val_len,
+            )) as *mut u8;
             if val.is_null() {
                 Ok(None)
             } else {
@@ -782,28 +819,27 @@ impl DB {
         }
     }
 
-    pub fn get_cf(&self,
-                  cf: ColumnFamily,
-                  key: &[u8])
-                  -> Result<Option<DBVector>, Error> {
+    pub fn get_cf(&self, cf: ColumnFamily, key: &[u8]) -> Result<Option<DBVector>, Error> {
         self.get_cf_opt(cf, key, &ReadOptions::default())
     }
 
-    pub fn create_cf(&mut self,
-                     name: &str,
-                     opts: &Options)
-                     -> Result<ColumnFamily, Error> {
+    pub fn create_cf(&mut self, name: &str, opts: &Options) -> Result<ColumnFamily, Error> {
         let cname = match CString::new(name.as_bytes()) {
             Ok(c) => c,
             Err(_) => {
-                return Err(Error::new("Failed to convert path to CString \
+                return Err(Error::new(
+                    "Failed to convert path to CString \
                                        when opening rocksdb"
-                    .to_owned()))
+                        .to_owned(),
+                ))
             }
         };
         let cf = unsafe {
-            let cf_handler =
-                ffi_try!(ffi::rocksdb_create_column_family(self.inner, opts.inner, cname.as_ptr()));
+            let cf_handler = ffi_try!(ffi::rocksdb_create_column_family(
+                self.inner,
+                opts.inner,
+                cname.as_ptr(),
+            ));
             let cf = ColumnFamily { inner: cf_handler };
             self.cfs.insert(name.to_string(), cf);
             cf
@@ -814,10 +850,15 @@ impl DB {
     pub fn drop_cf(&mut self, name: &str) -> Result<(), Error> {
         let cf = self.cfs.get(name);
         if cf.is_none() {
-            return Err(Error::new(format!("Invalid column family: {}", name).to_owned()));
+            return Err(Error::new(
+                format!("Invalid column family: {}", name).to_owned(),
+            ));
         }
         unsafe {
-            ffi_try!(ffi::rocksdb_drop_column_family(self.inner, cf.unwrap().inner));
+            ffi_try!(ffi::rocksdb_drop_column_family(
+                self.inner,
+                cf.unwrap().inner,
+            ));
         }
         Ok(())
     }
@@ -832,10 +873,11 @@ impl DB {
         DBIterator::new(self, &opts, mode)
     }
 
-    pub fn iterator_cf(&self,
-                       cf_handle: ColumnFamily,
-                       mode: IteratorMode)
-                       -> Result<DBIterator, Error> {
+    pub fn iterator_cf(
+        &self,
+        cf_handle: ColumnFamily,
+        mode: IteratorMode,
+    ) -> Result<DBIterator, Error> {
         let opts = ReadOptions::default();
         DBIterator::new_cf(self, cf_handle, &opts, mode)
     }
@@ -845,9 +887,7 @@ impl DB {
         DBRawIterator::new(self, &opts)
     }
 
-    pub fn raw_iterator_cf(&self,
-                       cf_handle: ColumnFamily)
-                       -> Result<DBRawIterator, Error> {
+    pub fn raw_iterator_cf(&self, cf_handle: ColumnFamily) -> Result<DBRawIterator, Error> {
         let opts = ReadOptions::default();
         DBRawIterator::new_cf(self, cf_handle, &opts)
     }
@@ -858,89 +898,105 @@ impl DB {
 
     pub fn put_opt(&self, key: &[u8], value: &[u8], writeopts: &WriteOptions) -> Result<(), Error> {
         unsafe {
-            ffi_try!(ffi::rocksdb_put(self.inner,
-                                      writeopts.inner,
-                                      key.as_ptr() as *const c_char,
-                                      key.len() as size_t,
-                                      value.as_ptr() as *const c_char,
-                                      value.len() as size_t));
+            ffi_try!(ffi::rocksdb_put(
+                self.inner,
+                writeopts.inner,
+                key.as_ptr() as *const c_char,
+                key.len() as size_t,
+                value.as_ptr() as *const c_char,
+                value.len() as size_t,
+            ));
             Ok(())
         }
     }
 
-    pub fn put_cf_opt(&self,
-                      cf: ColumnFamily,
-                      key: &[u8],
-                      value: &[u8],
-                      writeopts: &WriteOptions)
-                      -> Result<(), Error> {
+    pub fn put_cf_opt(
+        &self,
+        cf: ColumnFamily,
+        key: &[u8],
+        value: &[u8],
+        writeopts: &WriteOptions,
+    ) -> Result<(), Error> {
         unsafe {
-            ffi_try!(ffi::rocksdb_put_cf(self.inner,
-                                         writeopts.inner,
-                                         cf.inner,
-                                         key.as_ptr() as *const c_char,
-                                         key.len() as size_t,
-                                         value.as_ptr() as *const c_char,
-                                         value.len() as size_t));
+            ffi_try!(ffi::rocksdb_put_cf(
+                self.inner,
+                writeopts.inner,
+                cf.inner,
+                key.as_ptr() as *const c_char,
+                key.len() as size_t,
+                value.as_ptr() as *const c_char,
+                value.len() as size_t,
+            ));
             Ok(())
         }
     }
 
-    pub fn merge_opt(&self,
-                     key: &[u8],
-                     value: &[u8],
-                     writeopts: &WriteOptions)
-                     -> Result<(), Error> {
+    pub fn merge_opt(
+        &self,
+        key: &[u8],
+        value: &[u8],
+        writeopts: &WriteOptions,
+    ) -> Result<(), Error> {
         unsafe {
-            ffi_try!(ffi::rocksdb_merge(self.inner,
-                                        writeopts.inner,
-                                        key.as_ptr() as *const c_char,
-                                        key.len() as size_t,
-                                        value.as_ptr() as *const c_char,
-                                        value.len() as size_t));
+            ffi_try!(ffi::rocksdb_merge(
+                self.inner,
+                writeopts.inner,
+                key.as_ptr() as *const c_char,
+                key.len() as size_t,
+                value.as_ptr() as *const c_char,
+                value.len() as size_t,
+            ));
             Ok(())
         }
     }
 
-    pub fn merge_cf_opt(&self,
-                        cf: ColumnFamily,
-                        key: &[u8],
-                        value: &[u8],
-                        writeopts: &WriteOptions)
-                        -> Result<(), Error> {
+    pub fn merge_cf_opt(
+        &self,
+        cf: ColumnFamily,
+        key: &[u8],
+        value: &[u8],
+        writeopts: &WriteOptions,
+    ) -> Result<(), Error> {
         unsafe {
-            ffi_try!(ffi::rocksdb_merge_cf(self.inner,
-                                           writeopts.inner,
-                                           cf.inner,
-                                           key.as_ptr() as *const c_char,
-                                           key.len() as size_t,
-                                           value.as_ptr() as *const c_char,
-                                           value.len() as size_t));
+            ffi_try!(ffi::rocksdb_merge_cf(
+                self.inner,
+                writeopts.inner,
+                cf.inner,
+                key.as_ptr() as *const c_char,
+                key.len() as size_t,
+                value.as_ptr() as *const c_char,
+                value.len() as size_t,
+            ));
             Ok(())
         }
     }
 
     pub fn delete_opt(&self, key: &[u8], writeopts: &WriteOptions) -> Result<(), Error> {
         unsafe {
-            ffi_try!(ffi::rocksdb_delete(self.inner,
-                                         writeopts.inner,
-                                         key.as_ptr() as *const c_char,
-                                         key.len() as size_t));
+            ffi_try!(ffi::rocksdb_delete(
+                self.inner,
+                writeopts.inner,
+                key.as_ptr() as *const c_char,
+                key.len() as size_t,
+            ));
             Ok(())
         }
     }
 
-    pub fn delete_cf_opt(&self,
-                         cf: ColumnFamily,
-                         key: &[u8],
-                         writeopts: &WriteOptions)
-                         -> Result<(), Error> {
+    pub fn delete_cf_opt(
+        &self,
+        cf: ColumnFamily,
+        key: &[u8],
+        writeopts: &WriteOptions,
+    ) -> Result<(), Error> {
         unsafe {
-            ffi_try!(ffi::rocksdb_delete_cf(self.inner,
-                                            writeopts.inner,
-                                            cf.inner,
-                                            key.as_ptr() as *const c_char,
-                                            key.len() as size_t));
+            ffi_try!(ffi::rocksdb_delete_cf(
+                self.inner,
+                writeopts.inner,
+                cf.inner,
+                key.as_ptr() as *const c_char,
+                key.len() as size_t,
+            ));
             Ok(())
         }
     }
@@ -949,11 +1005,7 @@ impl DB {
         self.put_opt(key, value, &WriteOptions::default())
     }
 
-    pub fn put_cf(&self,
-                  cf: ColumnFamily,
-                  key: &[u8],
-                  value: &[u8])
-                  -> Result<(), Error> {
+    pub fn put_cf(&self, cf: ColumnFamily, key: &[u8], value: &[u8]) -> Result<(), Error> {
         self.put_cf_opt(cf, key, value, &WriteOptions::default())
     }
 
@@ -961,11 +1013,7 @@ impl DB {
         self.merge_opt(key, value, &WriteOptions::default())
     }
 
-    pub fn merge_cf(&self,
-                    cf: ColumnFamily,
-                    key: &[u8],
-                    value: &[u8])
-                    -> Result<(), Error> {
+    pub fn merge_cf(&self, cf: ColumnFamily, key: &[u8], value: &[u8]) -> Result<(), Error> {
         self.merge_cf_opt(cf, key, value, &WriteOptions::default())
     }
 
@@ -973,34 +1021,32 @@ impl DB {
         self.delete_opt(key, &WriteOptions::default())
     }
 
-    pub fn delete_cf(&self,
-                     cf: ColumnFamily,
-                     key: &[u8])
-                     -> Result<(), Error> {
+    pub fn delete_cf(&self, cf: ColumnFamily, key: &[u8]) -> 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);
+            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: ColumnFamily,
-                            start: Option<&[u8]>,
-                            end: Option<&[u8]>) {
+    pub fn compact_range_cf(&self, cf: ColumnFamily, start: Option<&[u8]>, end: Option<&[u8]>) {
         unsafe {
-            ffi::rocksdb_compact_range_cf(self.inner,
-                                          cf.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);
+            ffi::rocksdb_compact_range_cf(
+                self.inner,
+                cf.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,
+            );
         }
     }
 }
@@ -1017,54 +1063,54 @@ impl WriteBatch {
     /// Insert a value into the database under the given key.
     pub fn put(&mut self, key: &[u8], value: &[u8]) -> Result<(), Error> {
         unsafe {
-            ffi::rocksdb_writebatch_put(self.inner,
-                                        key.as_ptr() as *const c_char,
-                                        key.len() as size_t,
-                                        value.as_ptr() as *const c_char,
-                                        value.len() as size_t);
+            ffi::rocksdb_writebatch_put(
+                self.inner,
+                key.as_ptr() as *const c_char,
+                key.len() as size_t,
+                value.as_ptr() as *const c_char,
+                value.len() as size_t,
+            );
             Ok(())
         }
     }
 
-    pub fn put_cf(&mut self,
-                  cf: ColumnFamily,
-                  key: &[u8],
-                  value: &[u8])
-                  -> Result<(), Error> {
+    pub fn put_cf(&mut self, cf: ColumnFamily, key: &[u8], value: &[u8]) -> Result<(), Error> {
         unsafe {
-            ffi::rocksdb_writebatch_put_cf(self.inner,
-                                           cf.inner,
-                                           key.as_ptr() as *const c_char,
-                                           key.len() as size_t,
-                                           value.as_ptr() as *const c_char,
-                                           value.len() as size_t);
+            ffi::rocksdb_writebatch_put_cf(
+                self.inner,
+                cf.inner,
+                key.as_ptr() as *const c_char,
+                key.len() as size_t,
+                value.as_ptr() as *const c_char,
+                value.len() as size_t,
+            );
             Ok(())
         }
     }
 
     pub fn merge(&mut self, key: &[u8], value: &[u8]) -> Result<(), Error> {
         unsafe {
-            ffi::rocksdb_writebatch_merge(self.inner,
-                                          key.as_ptr() as *const c_char,
-                                          key.len() as size_t,
-                                          value.as_ptr() as *const c_char,
-                                          value.len() as size_t);
+            ffi::rocksdb_writebatch_merge(
+                self.inner,
+                key.as_ptr() as *const c_char,
+                key.len() as size_t,
+                value.as_ptr() as *const c_char,
+                value.len() as size_t,
+            );
             Ok(())
         }
     }
 
-    pub fn merge_cf(&mut self,
-                    cf: ColumnFamily,
-                    key: &[u8],
-                    value: &[u8])
-                    -> Result<(), Error> {
+    pub fn merge_cf(&mut self, cf: ColumnFamily, key: &[u8], value: &[u8]) -> Result<(), Error> {
         unsafe {
-            ffi::rocksdb_writebatch_merge_cf(self.inner,
-                                             cf.inner,
-                                             key.as_ptr() as *const c_char,
-                                             key.len() as size_t,
-                                             value.as_ptr() as *const c_char,
-                                             value.len() as size_t);
+            ffi::rocksdb_writebatch_merge_cf(
+                self.inner,
+                cf.inner,
+                key.as_ptr() as *const c_char,
+                key.len() as size_t,
+                value.as_ptr() as *const c_char,
+                value.len() as size_t,
+            );
             Ok(())
         }
     }
@@ -1074,22 +1120,23 @@ impl WriteBatch {
     /// Returns an error if the key was not found.
     pub fn delete(&mut self, key: &[u8]) -> Result<(), Error> {
         unsafe {
-            ffi::rocksdb_writebatch_delete(self.inner,
-                                           key.as_ptr() as *const c_char,
-                                           key.len() as size_t);
+            ffi::rocksdb_writebatch_delete(
+                self.inner,
+                key.as_ptr() as *const c_char,
+                key.len() as size_t,
+            );
             Ok(())
         }
     }
 
-    pub fn delete_cf(&mut self,
-                     cf: ColumnFamily,
-                     key: &[u8])
-                     -> Result<(), Error> {
+    pub fn delete_cf(&mut self, cf: ColumnFamily, key: &[u8]) -> Result<(), Error> {
         unsafe {
-            ffi::rocksdb_writebatch_delete_cf(self.inner,
-                                              cf.inner,
-                                              key.as_ptr() as *const c_char,
-                                              key.len() as size_t);
+            ffi::rocksdb_writebatch_delete_cf(
+                self.inner,
+                cf.inner,
+                key.as_ptr() as *const c_char,
+                key.len() as size_t,
+            );
             Ok(())
         }
     }
@@ -1149,9 +1196,11 @@ impl ReadOptions {
 
     pub fn set_iterate_upper_bound(&mut self, key: &[u8]) {
         unsafe {
-            ffi::rocksdb_readoptions_set_iterate_upper_bound(self.inner,
-                                                             key.as_ptr() as *const c_char,
-                                                             key.len() as size_t);
+            ffi::rocksdb_readoptions_set_iterate_upper_bound(
+                self.inner,
+                key.as_ptr() as *const c_char,
+                key.len() as size_t,
+            );
         }
     }
 }
@@ -1310,9 +1359,11 @@ fn iterator_test() {
         assert!(p.is_ok());
         let iter = db.iterator(IteratorMode::Start);
         for (k, v) in iter {
-            println!("Hello {}: {}",
-                     str::from_utf8(&*k).unwrap(),
-                     str::from_utf8(&*v).unwrap());
+            println!(
+                "Hello {}: {}",
+                str::from_utf8(&*k).unwrap(),
+                str::from_utf8(&*v).unwrap()
+            );
         }
     }
     let opts = Options::default();

src/db_options.rs

@@ -16,13 +16,13 @@
 
 use {BlockBasedOptions, DBCompactionStyle, DBCompressionType, DBRecoveryMode, Options,
      WriteOptions};
+use compaction_filter::{self, CompactionFilterCallback, CompactionFilterFn, filter_callback};
 use comparator::{self, ComparatorCallback, CompareFn};
 use ffi;
 
 use libc::{self, c_int, c_uchar, c_uint, c_void, size_t, uint64_t};
 use merge_operator::{self, MergeFn, MergeOperatorCallback, full_merge_callback,
                      partial_merge_callback};
-use compaction_filter::{self, CompactionFilterCallback, CompactionFilterFn, filter_callback};
 use std::ffi::{CStr, CString};
 use std::mem;
 
@@ -124,7 +124,8 @@ impl Options {
         unsafe {
             ffi::rocksdb_options_optimize_level_style_compaction(
                 self.inner,
-                memtable_memory_budget as uint64_t);
+                memtable_memory_budget as uint64_t,
+            );
         }
     }
 
@@ -190,10 +191,12 @@ impl Options {
     /// ```
     pub fn set_compression_per_level(&mut self, level_types: &[DBCompressionType]) {
         unsafe {
-            let level_types: Vec<_> = level_types.iter().map(|&t| t as c_int).collect();
-            ffi::rocksdb_options_set_compression_per_level(self.inner,
-                                                           level_types.as_ptr(),
-                                                           level_types.len() as size_t)
+            let mut level_types: Vec<_> = level_types.iter().map(|&t| t as c_int).collect();
+            ffi::rocksdb_options_set_compression_per_level(
+                self.inner,
+                level_types.as_mut_ptr(),
+                level_types.len() as size_t,
+            )
         }
     }
 
@@ -204,17 +207,20 @@ impl Options {
         });
 
         unsafe {
-            let mo = ffi::rocksdb_mergeoperator_create(mem::transmute(cb),
-                                                       Some(merge_operator::destructor_callback),
-                                                       Some(full_merge_callback),
-                                                       Some(partial_merge_callback),
-                                                       None,
-                                                       Some(merge_operator::name_callback));
+            let mo = ffi::rocksdb_mergeoperator_create(
+                mem::transmute(cb),
+                Some(merge_operator::destructor_callback),
+                Some(full_merge_callback),
+                Some(partial_merge_callback),
+                None,
+                Some(merge_operator::name_callback),
+            );
             ffi::rocksdb_options_set_merge_operator(self.inner, mo);
         }
     }
 
-    #[deprecated(since="0.5.0", note="add_merge_operator has been renamed to set_merge_operator")]
+    #[deprecated(since = "0.5.0",
+                 note = "add_merge_operator has been renamed to set_merge_operator")]
     pub fn add_merge_operator(&mut self, name: &str, merge_fn: MergeFn) {
         self.set_merge_operator(name, merge_fn);
     }
@@ -230,7 +236,8 @@ impl Options {
     /// If multi-threaded compaction is used, `filter_fn` may be called multiple times
     /// simultaneously.
     pub fn set_compaction_filter<F>(&mut self, name: &str, filter_fn: F)
-        where F: CompactionFilterFn + Send + 'static
+    where
+        F: CompactionFilterFn + Send + 'static,
     {
         let cb = Box::new(CompactionFilterCallback {
             name: CString::new(name.as_bytes()).unwrap(),
@@ -238,10 +245,12 @@ impl Options {
         });
 
         unsafe {
-            let cf = ffi::rocksdb_compactionfilter_create(mem::transmute(cb),
-                                                          Some(compaction_filter::destructor_callback::<F>),
-                                                          Some(filter_callback::<F>),
-                                                          Some(compaction_filter::name_callback::<F>));
+            let cf = ffi::rocksdb_compactionfilter_create(
+                mem::transmute(cb),
+                Some(compaction_filter::destructor_callback::<F>),
+                Some(filter_callback::<F>),
+                Some(compaction_filter::name_callback::<F>),
+            );
             ffi::rocksdb_options_set_compaction_filter(self.inner, cf);
         }
     }
@@ -259,10 +268,12 @@ impl Options {
         });
 
         unsafe {
-            let cmp = ffi::rocksdb_comparator_create(mem::transmute(cb),
-                                                     Some(comparator::destructor_callback),
-                                                     Some(comparator::compare_callback),
-                                                     Some(comparator::name_callback));
+            let cmp = ffi::rocksdb_comparator_create(
+                mem::transmute(cb),
+                Some(comparator::destructor_callback),
+                Some(comparator::compare_callback),
+                Some(comparator::name_callback),
+            );
             ffi::rocksdb_options_set_comparator(self.inner, cmp);
         }
     }
@@ -365,8 +376,9 @@ impl Options {
     /// opts.set_allow_concurrent_memtable_write(false);
     /// ```
     pub fn set_allow_concurrent_memtable_write(&mut self, allow: bool) {
-        unsafe { ffi::rocksdb_options_set_allow_concurrent_memtable_write(self.inner,
-                                                                          allow as c_uchar) }
+        unsafe {
+            ffi::rocksdb_options_set_allow_concurrent_memtable_write(self.inner, allow as c_uchar)
+        }
     }
 
     /// Enable direct I/O mode for reading
@@ -413,8 +425,10 @@ impl Options {
     /// ```
     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);
+            ffi::rocksdb_options_set_use_direct_io_for_flush_and_compaction(
+                self.inner,
+                enabled as c_uchar,
+            );
         }
     }
 
@@ -446,7 +460,8 @@ impl 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")]
+    #[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);
@@ -599,9 +614,9 @@ impl Options {
     /// use rocksdb::Options;
     ///
     /// let mut opts = Options::default();
-    /// opts.set_max_bytes_for_level_multiplier(4);
+    /// opts.set_max_bytes_for_level_multiplier(4.0);
     /// ```
-    pub fn set_max_bytes_for_level_multiplier(&mut self, mul: i32) {
+    pub fn set_max_bytes_for_level_multiplier(&mut self, mul: f64) {
         unsafe {
             ffi::rocksdb_options_set_max_bytes_for_level_multiplier(self.inner, mul);
         }

src/lib.rs

@@ -44,11 +44,12 @@ pub mod compaction_filter;
 mod db;
 mod db_options;
 
-pub use db::{DBCompactionStyle, DBCompressionType, DBIterator, DBRawIterator, DBRecoveryMode, DBVector,
-             ReadOptions, Direction, IteratorMode, Snapshot, WriteBatch, new_bloom_filter};
+pub use compaction_filter::Decision as CompactionDecision;
+pub use db::{DBCompactionStyle, DBCompressionType, DBIterator, DBRawIterator, DBRecoveryMode,
+             DBVector, ReadOptions, Direction, IteratorMode, Snapshot, WriteBatch,
+             new_bloom_filter};
 
 pub use merge_operator::MergeOperands;
-pub use compaction_filter::Decision as CompactionDecision;
 use std::collections::BTreeMap;
 use std::error;
 use std::fmt;

src/merge_operator.rs

@@ -76,17 +76,18 @@ pub unsafe extern "C" fn name_callback(raw_cb: *mut c_void) -> *const c_char {
     cb.name.as_ptr()
 }
 
-pub unsafe extern "C" fn full_merge_callback(raw_cb: *mut c_void,
-                                             raw_key: *const c_char,
-                                             key_len: size_t,
-                                             existing_value: *const c_char,
-                                             existing_value_len: size_t,
-                                             operands_list: *const *const c_char,
-                                             operands_list_len: *const size_t,
-                                             num_operands: c_int,
-                                             success: *mut u8,
-                                             new_value_length: *mut size_t)
-                                             -> *mut c_char {
+pub unsafe extern "C" fn full_merge_callback(
+    raw_cb: *mut c_void,
+    raw_key: *const c_char,
+    key_len: size_t,
+    existing_value: *const c_char,
+    existing_value_len: size_t,
+    operands_list: *const *const c_char,
+    operands_list_len: *const size_t,
+    num_operands: c_int,
+    success: *mut u8,
+    new_value_length: *mut size_t,
+) -> *mut c_char {
     let cb = &mut *(raw_cb as *mut MergeOperatorCallback);
     let operands = &mut MergeOperands::new(operands_list, operands_list_len, num_operands);
     let key = slice::from_raw_parts(raw_key as *const u8, key_len as usize);
@@ -102,15 +103,16 @@ pub unsafe extern "C" fn full_merge_callback(raw_cb: *mut c_void,
     buf as *mut c_char
 }
 
-pub unsafe extern "C" fn partial_merge_callback(raw_cb: *mut c_void,
-                                                raw_key: *const c_char,
-                                                key_len: size_t,
-                                                operands_list: *const *const c_char,
-                                                operands_list_len: *const size_t,
-                                                num_operands: c_int,
-                                                success: *mut u8,
-                                                new_value_length: *mut size_t)
-                                                -> *mut c_char {
+pub unsafe extern "C" fn partial_merge_callback(
+    raw_cb: *mut c_void,
+    raw_key: *const c_char,
+    key_len: size_t,
+    operands_list: *const *const c_char,
+    operands_list_len: *const size_t,
+    num_operands: c_int,
+    success: *mut u8,
+    new_value_length: *mut size_t,
+) -> *mut c_char {
     let cb = &mut *(raw_cb as *mut MergeOperatorCallback);
     let operands = &mut MergeOperands::new(operands_list, operands_list_len, num_operands);
     let key = slice::from_raw_parts(raw_key as *const u8, key_len as usize);
@@ -134,10 +136,11 @@ pub struct MergeOperands {
 }
 
 impl MergeOperands {
-    fn new(operands_list: *const *const c_char,
-           operands_list_len: *const size_t,
-           num_operands: c_int)
-           -> MergeOperands {
+    fn new(
+        operands_list: *const *const c_char,
+        operands_list_len: *const size_t,
+        num_operands: c_int,
+    ) -> MergeOperands {
         assert!(num_operands >= 0);
         MergeOperands {
             operands_list: operands_list,
@@ -164,8 +167,10 @@ impl<'a> Iterator for &'a mut MergeOperands {
                 let len = *len_ptr as usize;
                 let ptr = base + (spacing * self.cursor);
                 self.cursor += 1;
-                Some(mem::transmute(slice::from_raw_parts(*(ptr as *const *const u8) as *const u8,
-                                                          len)))
+                Some(mem::transmute(slice::from_raw_parts(
+                    *(ptr as *const *const u8) as *const u8,
+                    len,
+                )))
             }
         }
     }
@@ -178,10 +183,11 @@ impl<'a> Iterator for &'a mut MergeOperands {
 
 #[cfg(test)]
 #[allow(unused_variables)]
-fn test_provided_merge(new_key: &[u8],
-                       existing_val: Option<&[u8]>,
-                       operands: &mut MergeOperands)
-                       -> Vec<u8> {
+fn test_provided_merge(
+    new_key: &[u8],
+    existing_val: Option<&[u8]>,
+    operands: &mut MergeOperands,
+) -> Vec<u8> {
     let nops = operands.size_hint().0;
     let mut result: Vec<u8> = Vec::with_capacity(nops);
     if let Some(v) = existing_val {