Implement crc32c for Darwin, update documentation

BUILDDEPS.md

@@ -50,9 +50,9 @@ This installation document assumes Mac OSX Yosemite 10.10 or later on x86-64 pla
 $ ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
 ```
 
-##### Install Git and GCC
+##### Install Git
 ```sh
-$ brew install git gcc
+$ brew install git
 ```
 
 ##### Install YASM
@@ -64,7 +64,6 @@ $ brew install yasm
 ```
 
 ##### Install Go 1.4+
-
 On MacOSX ``brew.sh`` is the best way to install golang
 
 For example:

Makefile

@@ -1,7 +1,6 @@
 #GOPATH := $(CURDIR)/tmp/gopath
 MAKE_OPTIONS := -s
 ARCH := $(shell uname -s)
-GCCVERSIONGTEQ4 := $(shell expr `gcc -dumpversion | cut -f1 -d.` \>= 4)
 
 all: getdeps install
 
@@ -20,13 +19,7 @@ build-utils:
 	@godep go test -race -coverprofile=cover.out github.com/minio-io/minio/pkg/utils/crypto/sha1
 	@godep go test -race -coverprofile=cover.out github.com/minio-io/minio/pkg/utils/crypto/sha256
 	@godep go test -race -coverprofile=cover.out github.com/minio-io/minio/pkg/utils/crypto/sha512
-ifeq ($(ARCH), Darwin)
-ifeq ($(GCCVERSIONGTEQ4), "1")
 	@godep go test -race -coverprofile=cover.out github.com/minio-io/minio/pkg/utils/checksum/crc32c
-endif
-else
-	@godep go test -race -coverprofile=cover.out github.com/minio-io/minio/pkg/utils/checksum/crc32c
-endif
 
 #build-os:
 #	@godep go test -race -coverprofile=cover.out github.com/minio-io/minio/pkg/os/scsi

README.md

@@ -23,7 +23,7 @@ Minio's design is inspired by Amazon's S3 for its API and Facebook's Haystack fo
 | ------------- | ------------- |
 | Linux  | Yes  |
 | Windows | Not yet |
-| Mac OSX | Yes(with GCC) |
+| Mac OSX | Yes |
 
 ### Supported architectures
 

pkg/utils/checksum/crc32c/crc32c_darwin.go

@@ -0,0 +1,35 @@
+/*
+ * Mini Object Storage, (C) 2014 Minio, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// +build amd64
+
+package crc32c
+
+import (
+	"errors"
+        "hash/crc32"
+)
+
+var castanagoliTable = crc32.MakeTable(crc32.Castagnoli)
+
+func Crc32c(buffer []byte) (uint32, error) {
+        crc := crc32.New(castanagoliTable)
+        if len(buffer) <= 0 {
+           return 0, errors.New("input buffer cannot be null")
+        }
+        crc.Write(buffer)
+	return crc.Sum32(), nil
+}