Split out littlefs mbed-os implementation from 'ca7b5e8eed574a7295280…

…d9276de3f9bb7cb7f05'

This is not a true subtree split due to the complication moves in the
mbed-os tree. While I could patch the history together to keep the
subtree intact, the ultimate goal for this split is to be merged in
parallel to littlefs-v1. This would give us duplicate histories anyway
so it's probably better to keep this split as a single squashed commit.

source-dir: features/storage/filesystem/littlefs/littlefs
source-hash: ca7b5e8

.mbedignore

@@ -0,0 +1,3 @@
+littlefs/emubd/
+littlefs/tests/
+TESTS/util

.travis.yml

@@ -0,0 +1,70 @@
+script:
+      # Check that example compiles
+    - sed -n '/``` c++/,/```/{/```/d; p;}' README.md > main.cpp
+    - PYTHONPATH=mbed-os python mbed-os/tools/make.py -t GCC_ARM -m K82F
+          --source=. --build=BUILD/K82F/GCC_ARM -j0      
+
+      # Check that tests compile
+    - rm -rf main.cpp BUILD
+    - PYTHONPATH=mbed-os python mbed-os/tools/test.py -t GCC_ARM -m K82F
+          --source=. --build=BUILD/TESTS/K82F/GCC_ARM -j0
+          -n 'tests*'
+
+      # Run littlefs functional tests
+    - CFLAGS="-Wno-format" make -Clittlefs test QUIET=1
+
+      # Run littlefs functional tests with different configurations
+      # Note: r/w size of 64 is default in mbed
+    - CFLAGS="-Wno-format -DLFS_READ_SIZE=64 -DLFS_PROG_SIZE=64"
+            make -Clittlefs test QUIET=1
+    - CFLAGS="-Wno-format -DLFS_READ_SIZE=1 -DLFS_PROG_SIZE=1"
+            make -Clittlefs test QUIET=1
+    - CFLAGS="-Wno-format -DLFS_READ_SIZE=512 -DLFS_PROG_SIZE=512"
+            make -Clittlefs test QUIET=1
+    - CFLAGS="-Wno-format -DLFS_BLOCK_COUNT=1023"
+            make -Clittlefs test QUIET=1
+    - CFLAGS="-Wno-format -DLFS_LOOKAHEAD=2048"
+            make -Clittlefs test QUIET=1
+
+      # Self-host with littlefs-fuse for fuzz test
+    - CFLAGS="-Wno-format" make -C littlefs-fuse
+
+    - littlefs-fuse/lfs --format /dev/loop0
+    - littlefs-fuse/lfs /dev/loop0 mount
+
+    - ls mount
+    - mkdir mount/littlefs
+    - cp -r $(git ls-tree --name-only HEAD littlefs/) mount/littlefs
+    - cd mount/littlefs
+    - ls
+    - CFLAGS="-Wno-format" make -B test_dirs QUIET=1
+
+install:
+      # Get arm-none-eabi-gcc
+    - sudo add-apt-repository -y ppa:terry.guo/gcc-arm-embedded
+    - sudo apt-get update -qq
+    - sudo apt-get install -qq gcc-arm-none-eabi --force-yes
+      # Get dependencies
+    - git clone https://github.com/armmbed/mbed-os.git
+    - git clone https://github.com/armmbed/spiflash-driver.git
+      # Install python dependencies
+    - pip install --user -r mbed-os/requirements.txt
+      # Install littlefs-fuse and dependencies
+    - sudo apt-get install libfuse-dev
+    - git clone https://github.com/geky/littlefs-fuse
+      # Check versions
+    - fusermount -V
+    - arm-none-eabi-gcc --version
+    - python --version
+    - gcc --version
+
+before_script:
+      # Patch littlefs-fuse
+    - rm -rf littlefs-fuse/littlefs/*
+    - cp -r $(git ls-tree --name-only HEAD littlefs/) littlefs-fuse/littlefs
+    - echo '*' > littlefs-fuse/.mbedignore
+      # Create file-backed disk
+    - mkdir mount
+    - sudo chmod a+rw /dev/loop0
+    - dd if=/dev/zero bs=512 count=2048 of=disk
+    - losetup /dev/loop0 disk