circuitpython/tests/extmod/vfs_userfs.py

69 lines
1.6 KiB
Python

# test VFS functionality with a user-defined filesystem
# also tests parts of uio.IOBase implementation
import sys, uio
try:
uio.IOBase
import uos
uos.mount
except (ImportError, AttributeError):
print("SKIP")
raise SystemExit
class UserFile(uio.IOBase):
def __init__(self, data):
self.data = data
self.pos = 0
def read(self):
return self.data
def readinto(self, buf):
n = 0
while n < len(buf) and self.pos < len(self.data):
buf[n] = self.data[self.pos]
n += 1
self.pos += 1
return n
def ioctl(self, req, arg):
print('ioctl', req, arg)
return 0
class UserFS:
def __init__(self, files):
self.files = files
def mount(self, readonly, mksfs):
pass
def umount(self):
pass
def stat(self, path):
print('stat', path)
if path in self.files:
return (32768, 0, 0, 0, 0, 0, 0, 0, 0, 0)
raise OSError
def open(self, path, mode):
print('open', path, mode)
return UserFile(self.files[path])
# create and mount a user filesystem
user_files = {
'/data.txt': b"some data in a text file\n",
'/usermod1.py': b"print('in usermod1')\nimport usermod2",
'/usermod2.py': b"print('in usermod2')",
}
uos.mount(UserFS(user_files), '/userfs')
# open and read a file
f = open('/userfs/data.txt')
print(f.read())
# import files from the user filesystem
sys.path.append('/userfs')
import usermod1
# unmount and undo path addition
uos.umount('/userfs')
sys.path.pop()