Enable macOS Support

- based on littlefs-project#19

Makefile

@@ -23,12 +23,15 @@ override CFLAGS += -I. -Ilittlefs
 override CFLAGS += -std=c99 -Wall -pedantic
 override CFLAGS += -D_FILE_OFFSET_BITS=64
 override CFLAGS += -D_XOPEN_SOURCE=700
-# enable multiversion support in littlefs
-override CFLAGS += -DLFS_MULTIVERSION
-# enable migrate support in littlefs
 override CFLAGS += -DLFS_MIGRATE
 
+ifeq ($(OS), Darwin)
+override CFLAGS += -I /usr/local/include/osxfuse
+override LFLAGS += -L /usr/local/lib
+override LFLAGS += -losxfuse
+else
 override LFLAGS += -lfuse
+endif
 
 ifeq ($(OS), FreeBSD)
 override CFLAGS += -I /usr/local/include
@@ -61,4 +64,4 @@ clean:
 	rm -f $(TARGET)
 	rm -f $(OBJ)
 	rm -f $(DEP)
-	rm -f $(ASM)
+	rm -f $(ASM)

README.md

@@ -16,8 +16,13 @@ This comes with a performance penalty, but works well for the littlefs,
 since littlefs is intended for embedded systems.
 
 Currently littlefs-fuse has been tested on the following OSs:
-- [Linux](#usage-on-linux)
-- [FreeBSD](#usage-on-freebsd)
+
+- [The little filesystem in user-space](#the-little-filesystem-in-user-space)
+- [Usage on Linux](#usage-on-linux)
+- [Usage on FreeBSD](#usage-on-freebsd)
+- [Usage on macOS](#usage-on-macos)
+- [Limitations](#limitations)
+- [Tips](#tips)
 
 ## Usage on Linux
 
@@ -132,6 +137,58 @@ umount mount
 sudo mdconfig -du 0
 ```
 
+## Usage on macOS
+
+littlefs-fuse requires [osxfuse](https://osxfuse.github.io/) for macOS:
+```bash
+brew cask install osxfuse
+```
+
+Once you have cloned littlefs-fuse, you can compile the program with make:
+``` bash
+make
+```
+
+This should have built the `lfs` program in the top-level directory.
+
+From here we will need a block device. If you don't have removable storage
+handy, you can use a file-backed block device with FreeBSD's loop devices:
+``` bash
+dd if=/dev/zero of=image bs=1m count=1                                  # create a 1 MB image
+hdiutil attach -imagekey diskimage-class=CRawDiskImage -nomount image   # attach the loop device
+sudo chmod 666 /dev/diskX                                               # make loop device user accessible,
+```
+
+littlefs-fuse has two modes of operation, formatting and mounting.
+
+To format a block device, pass the `--format` flag. Note! This will erase any
+data on the block device!
+``` bash
+./lfs --format /dev/diskX
+```
+
+To mount, run littlefs-fuse with a block device and a mountpoint:
+``` bash
+mkdir mount
+./lfs /dev/diskX mount
+```
+
+Once mounted, the littlefs filesystem will be accessible through the
+mountpoint. You can now use the littlefs like you would any other filesystem:
+``` bash
+cd mount
+echo "hello" > hi.txt
+ls
+cat hi.txt
+```
+
+After using littlefs, you can unmount and detach the loop device:
+``` bash
+cd ..
+hdiutil unmount /dev/diskX
+hdiutil detach /dev/diskX
+```
+
 ## Limitations
 
 As an embedded filesystem, littlefs is designed to be simple. By default,

lfs_fuse_bd.c

@@ -12,16 +12,21 @@
 #include <fcntl.h>
 #include <stdint.h>
 #include <assert.h>
-#if !defined(__FreeBSD__)
-#include <sys/ioctl.h>
-#include <linux/fs.h>
-#elif defined(__FreeBSD__)
+#if defined(__FreeBSD__)
 #define BLKSSZGET DIOCGSECTORSIZE
 #define BLKGETSIZE DIOCGMEDIASIZE
 #include <sys/disk.h>
+#elif defined(__APPLE__)
+#define BLKSSZGET DKIOCGETBLOCKSIZE
+#define BLKGETSIZE DKIOCGETBLOCKCOUNT
+#include <sys/disk.h>
+#elif defined(__LINUX__)
+#include <sys/ioctl.h>
+#include <linux/fs.h>
+#else
+#error ("Unsupported OS")
 #endif
 
-
 // Block device wrapper for user-space block devices
 int lfs_fuse_bd_create(struct lfs_config *cfg, const char *path) {
     int fd = open(path, O_RDWR);