*: reorganize code (#6)

* seperate ffi crate
* fix clippy warning

Cargo.toml

@@ -26,3 +26,6 @@ path = "test/test.rs"
 [dependencies]
 libc = "0.1.8"
 tempdir = "0.3.4"
+
+[dependencies.librocksdb_sys]
+path = "librocksdb_sys"

librocksdb_sys/Cargo.toml

+[package]
+name = "librocksdb_sys"
+version = "0.1.0"
+authors = ["Jay Lee <busyjaylee@gmail.com>"]
+
+[dependencies]
+libc = "0.1.8"

src/ffi.rs → librocksdb_sys/src/lib.rs

@@ -12,7 +12,10 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 //
-use libc::{self, c_char, c_int, c_void, size_t, uint64_t};
+
+extern crate libc;
+
+use libc::{c_char, c_int, c_void, size_t, uint64_t};
 use std::ffi::CStr;
 use std::str::from_utf8;
 

src/lib.rs

@@ -18,14 +18,14 @@ extern crate libc;
 
 #[cfg(test)]
 extern crate tempdir;
+pub extern crate librocksdb_sys;
 
 pub mod rocksdb;
-pub mod ffi;
 pub mod rocksdb_options;
 pub mod merge_operator;
 pub mod comparator;
 
-pub use ffi::{DBCompactionStyle, DBComparator, new_bloom_filter,
+pub use librocksdb_sys::{DBCompactionStyle, DBComparator, new_bloom_filter,
                          self as rocksdb_ffi};
 pub use rocksdb::{DB, DBIterator, DBVector, Direction, IteratorMode, Writable,
                   WriteBatch};

src/merge_operator.rs

@@ -19,9 +19,11 @@ use std::ptr;
 use std::slice;
 
 
+pub type MergeFn = fn(&[u8], Option<&[u8]>, &mut MergeOperands) -> Vec<u8>;
+
 pub struct MergeOperatorCallback {
     pub name: CString,
-    pub merge_fn: fn(&[u8], Option<&[u8]>, &mut MergeOperands) -> Vec<u8>,
+    pub merge_fn: MergeFn,
 }
 
 pub extern "C" fn destructor_callback(raw_cb: *mut c_void) {
@@ -39,6 +41,7 @@ pub extern "C" fn name_callback(raw_cb: *mut c_void) -> *const c_char {
     }
 }
 
+#[allow(too_many_arguments)]
 pub extern "C" fn full_merge_callback(raw_cb: *mut c_void,
                                       raw_key: *const c_char,
                                       key_len: size_t,
@@ -72,6 +75,7 @@ pub extern "C" fn full_merge_callback(raw_cb: *mut c_void,
     }
 }
 
+#[allow(too_many_arguments)]
 pub extern "C" fn partial_merge_callback(raw_cb: *mut c_void,
                                          raw_key: *const c_char,
                                          key_len: size_t,

src/rocksdb.rs

@@ -59,12 +59,17 @@ pub enum Direction {
     Reverse,
 }
 
+// TODO: should we use Vec<u8> instead?
+pub type Kv = (Box<[u8]>, Box<[u8]>);
+
 impl Iterator for DBIterator {
-    type Item = (Box<[u8]>, Box<[u8]>);
+    type Item = Kv;
 
-    fn next(&mut self) -> Option<(Box<[u8]>, Box<[u8]>)> {
+    fn next(&mut self) -> Option<Kv> {
         let native_iter = self.inner;
-        if !self.just_seeked {
+        if self.just_seeked {
+            self.just_seeked = false;
+        } else {
             match self.direction {
                 Direction::Forward => unsafe {
                     rocksdb_ffi::rocksdb_iter_next(native_iter)
@@ -73,8 +78,6 @@ impl Iterator for DBIterator {
                     rocksdb_ffi::rocksdb_iter_prev(native_iter)
                 },
             }
-        } else {
-            self.just_seeked = false;
         }
         if unsafe { rocksdb_ffi::rocksdb_iter_valid(native_iter) } {
             let mut key_len: size_t = 0;
@@ -240,9 +243,9 @@ pub trait Writable {
     fn delete_cf(&self, cf: DBCFHandle, key: &[u8]) -> Result<(), String>;
 }
 
-/// A range of keys, start_key is included, but not end_key.
+/// A range of keys, `start_key` is included, but not `end_key`.
 ///
-/// You should make sure end_key is not less than start_key.
+/// You should make sure `end_key` is not less than `start_key`.
 pub struct Range<'a> {
     start_key: &'a [u8],
     end_key: &'a [u8],
@@ -336,14 +339,14 @@ impl DB {
                      .collect();
 
             // Prepare to ship to C.
-            let copts: *const rocksdb_ffi::DBOptions = cfopts.as_ptr();
+            let cfopts_ptr: *const rocksdb_ffi::DBOptions = cfopts.as_ptr();
             let handles: *const rocksdb_ffi::DBCFHandle = cfhandles.as_ptr();
             let nfam = cfs_v.len();
             unsafe {
                 db = rocksdb_ffi::rocksdb_open_column_families(opts.inner, cpath_ptr as *const _,
                                                                nfam as c_int,
                                                                cfnames.as_ptr() as *const _,
-                                                               copts, handles, err_ptr);
+                                                               cfopts_ptr, handles, err_ptr);
             }
 
             for handle in &cfhandles {
@@ -763,8 +766,12 @@ impl DB {
                                            .map(|x| x.end_key.len() as u64)
                                            .collect();
         let mut sizes: Vec<u64> = vec![0; ranges.len()];
-        let (n, sk_ptr, skl_ptr, ek_ptr, ekl_ptr, s_ptr) =
-            (ranges.len() as i32,
+        let (n,
+             start_key_ptr,
+             start_key_len_ptr,
+             end_key_ptr,
+             end_key_len_ptr,
+             size_ptr) = (ranges.len() as i32,
                           start_keys.as_ptr(),
                           start_key_lens.as_ptr(),
                           end_keys.as_ptr(),
@@ -774,21 +781,21 @@ impl DB {
             None => unsafe {
                 rocksdb_ffi::rocksdb_approximate_sizes(self.inner,
                                                        n,
-                                                       sk_ptr,
-                                                       skl_ptr,
-                                                       ek_ptr,
-                                                       ekl_ptr,
-                                                       s_ptr)
+                                                       start_key_ptr,
+                                                       start_key_len_ptr,
+                                                       end_key_ptr,
+                                                       end_key_len_ptr,
+                                                       size_ptr)
             },
             Some(cf) => unsafe {
                 rocksdb_ffi::rocksdb_approximate_sizes_cf(self.inner,
                                                           cf,
                                                           n,
-                                                          sk_ptr,
-                                                          skl_ptr,
-                                                          ek_ptr,
-                                                          ekl_ptr,
-                                                          s_ptr)
+                                                          start_key_ptr,
+                                                          start_key_len_ptr,
+                                                          end_key_ptr,
+                                                          end_key_len_ptr,
+                                                          size_ptr)
             },
         }
         sizes
@@ -829,14 +836,20 @@ impl Writable for DB {
     }
 }
 
-impl WriteBatch {
-    pub fn new() -> WriteBatch {
+impl Default for WriteBatch {
+    fn default() -> WriteBatch {
         WriteBatch {
             inner: unsafe { rocksdb_ffi::rocksdb_writebatch_create() },
         }
     }
 }
 
+impl WriteBatch {
+    pub fn new() -> WriteBatch {
+        WriteBatch::default()
+    }
+}
+
 impl Drop for WriteBatch {
     fn drop(&mut self) {
         unsafe { rocksdb_ffi::rocksdb_writebatch_destroy(self.inner) }
@@ -935,12 +948,18 @@ impl Drop for ReadOptions {
     }
 }
 
-impl ReadOptions {
-    fn new() -> ReadOptions {
+impl Default for ReadOptions {
+    fn default() -> ReadOptions {
         unsafe {
             ReadOptions { inner: rocksdb_ffi::rocksdb_readoptions_create() }
         }
     }
+}
+
+impl ReadOptions {
+    fn new() -> ReadOptions {
+        ReadOptions::default()
+    }
     // TODO add snapshot setting here
     // TODO add snapshot wrapper structs with proper destructors;
     // that struct needs an "iterator" impl too.

src/rocksdb_options.rs

@@ -17,9 +17,10 @@ use std::ffi::CString;
 use std::mem;
 
 use rocksdb_ffi;
-use merge_operator::{self, MergeOperands, MergeOperatorCallback,
-                     full_merge_callback, partial_merge_callback};
+use merge_operator::{self, MergeOperatorCallback, full_merge_callback,
+                     partial_merge_callback};
 use comparator::{self, ComparatorCallback, compare_callback};
+use merge_operator::MergeFn;
 
 pub struct BlockBasedOptions {
     inner: rocksdb_ffi::DBBlockBasedTableOptions,
@@ -57,8 +58,8 @@ impl Drop for WriteOptions {
     }
 }
 
-impl BlockBasedOptions {
-    pub fn new() -> BlockBasedOptions {
+impl Default for BlockBasedOptions {
+    fn default() -> BlockBasedOptions {
         let block_opts = unsafe {
             rocksdb_ffi::rocksdb_block_based_options_create()
         };
@@ -68,6 +69,12 @@ impl BlockBasedOptions {
         }
         BlockBasedOptions { inner: block_opts }
     }
+}
+
+impl BlockBasedOptions {
+    pub fn new() -> BlockBasedOptions {
+        BlockBasedOptions::default()
+    }
 
     pub fn set_block_size(&mut self, size: u64) {
         unsafe {
@@ -85,24 +92,24 @@ impl BlockBasedOptions {
 // /    }
 // /}
 
-/// /pub fn set_cache(&mut self, cache: rocksdb_ffi::DBCache) {
-/// /    unsafe {
-/// /        rocksdb_ffi::rocksdb_block_based_options_set_block_cache(
-/// /            self.inner, cache);
-/// /    }
-/// /}
+// /pub fn set_cache(&mut self, cache: rocksdb_ffi::DBCache) {
+// /    unsafe {
+// /        rocksdb_ffi::rocksdb_block_based_options_set_block_cache(
+// /            self.inner, cache);
+// /    }
+// /}
 
-/// /pub fn set_cache_compressed(&mut self, cache: rocksdb_ffi::DBCache) {
-/// /    unsafe {
-/// /        rocksdb_ffi::
-/// rocksdb_block_based_options_set_block_cache_compressed(
-/// /            self.inner, cache);
-/// /    }
-/// /}
+// /pub fn set_cache_compressed(&mut self, cache: rocksdb_ffi::DBCache) {
+// /    unsafe {
+// /        rocksdb_ffi::
+// rocksdb_block_based_options_set_block_cache_compressed(
+// /            self.inner, cache);
+// /    }
+// /}
 
 
-impl Options {
-    pub fn new() -> Options {
+impl Default for Options {
+    fn default() -> Options {
         unsafe {
             let opts = rocksdb_ffi::rocksdb_options_create();
             let rocksdb_ffi::DBOptions(opt_ptr) = opts;
@@ -112,6 +119,12 @@ impl Options {
             Options { inner: opts }
         }
     }
+}
+
+impl Options {
+    pub fn new() -> Options {
+        Options::default()
+    }
 
     pub fn increase_parallelism(&mut self, parallelism: i32) {
         unsafe {
@@ -135,12 +148,7 @@ impl Options {
         }
     }
 
-    pub fn add_merge_operator(&mut self,
-                              name: &str,
-                              merge_fn: fn(&[u8],
-                                           Option<&[u8]>,
-                                           &mut MergeOperands)
-                                           -> Vec<u8>) {
+    pub fn add_merge_operator(&mut self, name: &str, merge_fn: MergeFn) {
         let cb = Box::new(MergeOperatorCallback {
             name: CString::new(name.as_bytes()).unwrap(),
             merge_fn: merge_fn,
@@ -304,13 +312,10 @@ impl Options {
 
     pub fn set_disable_auto_compactions(&mut self, disable: bool) {
         unsafe {
-            match disable {
-                true =>
-                    rocksdb_ffi::rocksdb_options_set_disable_auto_compactions(
-                        self.inner, 1),
-                false =>
-                    rocksdb_ffi::rocksdb_options_set_disable_auto_compactions(
-                        self.inner, 0),
+            if disable {
+                rocksdb_ffi::rocksdb_options_set_disable_auto_compactions(self.inner, 1)
+            } else {
+                rocksdb_ffi::rocksdb_options_set_disable_auto_compactions(self.inner, 0)
             }
         }
     }
@@ -323,8 +328,8 @@ impl Options {
     }
 }
 
-impl WriteOptions {
-    pub fn new() -> WriteOptions {
+impl Default for WriteOptions {
+    fn default() -> WriteOptions {
         let write_opts = unsafe { rocksdb_ffi::rocksdb_writeoptions_create() };
         let rocksdb_ffi::DBWriteOptions(opt_ptr) = write_opts;
         if opt_ptr.is_null() {
@@ -332,6 +337,12 @@ impl WriteOptions {
         }
         WriteOptions { inner: write_opts }
     }
+}
+
+impl WriteOptions {
+    pub fn new() -> WriteOptions {
+        WriteOptions::default()
+    }
     pub fn set_sync(&mut self, sync: bool) {
         unsafe {
             rocksdb_ffi::rocksdb_writeoptions_set_sync(self.inner, sync);