def create(fname):
for fdn in range(1, 24): #A
if (io.read_fdc(fdn, 0) == 193):
entry = 24 #B
lenlimit = False
lseek(0, 0, True) #C
slot = bytearray(8)
n = 0
for j in range(0, 24):
n = j
if (io.bti(io.oft, 72) == 0):
entry = j
break
if (lenlimit == False and read(0, slot, 8) == 0): #D
lenlimit = True
if (entry == 24 and (io.bti(slot, 0) == 0)): #E
entry = j
elif (io.bts(slot, 0) == fname): #F
return 1
if (entry == 24 and j < 23 and lenlimit):
entry = j
break
if (entry == 24): #G
return 1
lseek(0, entry * 8, True) #H
write(0, io.stb(fname) + io.itb(fdn), 8) #I
io.write_fdc(0, fdn, 0) #J
return 0
return 1
def read(index, mem_area, count):
if (io.bti(io.oft, index * 76 + 72) == 193): #A
return 193
pos = io.bti(io.oft, index * 76 + 64)
bn = 4 if int(pos / 64) == 0 else 8 if int(pos / 64) == 1 else 12
readmax = io.bti(io.oft, index * 76 + 72) - pos #B
nread = min(count, readmax)
for j in range(0, nread): #C
mem_area[j] = io.oft[index * 76 + pos % 64] #D
pos += 1
lseek(index, pos, False) #E
return nread
def write(index, mem_area, count):
flen = io.bti(io.oft, index * 76 + 72)
if (flen == 193):
return 193
pos = io.bti(io.oft, index * 76 + 64)
bn = 4 if int(pos / 64) == 0 else 8 if int(pos / 64) == 1 else 12
nwrite = min(count, 192 - pos)
for j in range(0, nwrite): #A
io.oft[index * 76 + pos % 64] = mem_area[j] #B
pos += 1
lseek(index, pos, True)
io.insert_int(min(flen + nwrite, 192), io.oft, index * 76 + 72) #C
return nwrite
def close_file(index):
if (index > 3 or io.bti(io.oft, index * 76 + 72) == 193): #A
return 1
fdn = io.bti(io.oft, index * 76 + 68) #B
pos = io.bti(io.oft, index * 76 + 64) #B
bn = 4 if int(pos / 64) == 0 else 8 if int(pos / 64) == 1 else 12 #C
blockn = io.read_fdc(fdn, bn)
io.write_block(blockn, io.ofte_buff(index)) #D
io.write_fdc(io.bti(io.oft, index * 76 + 72), fdn, 0) #E
if (index > 0):
io.insert_int(0, io.oft, index * 76 + 68) #F
io.insert_int(193, io.oft, index * 76 + 72) #F
return 0
def directory():
lseek(0, 0, False)
slot = bytearray(8)
files = []
for i in range(0, 24):
read(0, slot, 8)
fname = io.bts(slot, 0)
if (fname in files):
break
if (io.bti(slot, 0) != 0):
files.append(fname)
return files
def lseek(index, pos, overlim):
flen = io.bti(io.oft, index * 76 + 72)
if ((not overlim and pos > flen) or flen == 193):
return 1
curr = io.bti(io.oft, index * 76 + 64)
cbn = 4 if int(curr / 64) == 0 else 8 if int(curr / 64) == 1 else 12
fdn = io.bti(io.oft, index * 76 + 68)
if (io.read_fdc(fdn, cbn) == 0): #A
io.allocate_block(fdn, 4)
else:
if (int(pos / 64) != int(curr / 64)): #B
io.write_block(io.read_fdc(fdn, cbn), io.ofte_buff(index)) #C
bn = 4 if int(pos / 64) == 0 else 8 if int(pos / 64) == 1 else 12
blockn = io.read_fdc(fdn, bn) #D
if (blockn == 0): #E
c = io.allocate_block(fdn, bn) #F
if (c[0] == 0 and overlim == True):
io.read_block(c[1], index)
else:
io.read_block(blockn, index) #G
io.insert_int(pos, io.oft, index * 76 + 64) #H
return 0
def open_file(fname):
lseek(0, 0, False)
slot = bytearray(8)
for i in range(0, 24):
read(0, slot, 8)
if (io.bts(slot, 0) == fname): #A
fdn = io.bti(slot, 4)
index = 4
for j in range(1, 4):
if (io.bti(io.oft, j * 76 + 68) == fdn): #B
return 1
elif (index == 4 and io.bti(io.oft, j * 76 + 72) == 193): #C
index = j
if (index == 4): #D
return 4
io.insert_int(0, io.oft, index * 76 + 64) #E
io.insert_int(fdn, io.oft, index * 76 + 68) #E
io.insert_int(io.read_fdc(fdn, 0), io.oft, index * 76 + 72) #E
blockn = io.read_fdc(fdn, 4)
if (blockn > 0):
io.read_block(blockn, index) #F
return index
return 4
def destroy(fname):
lseek(0, 0, False)
slot = bytearray(8)
for entry in range(0, 24):
read(0, slot, 8)
if (io.bts(slot, 0) == fname): #A
fdn = io.bti(slot, 4) #B
io.write_fdc(193, fdn, 0) #C
for bn in [4, 8, 12]:
blockn = io.read_fdc(fdn, bn)
if (blockn > 0):
io.deallocate_block(blockn, fdn, bn) #D
lseek(0, entry * 8, False)
io.insert_int(0, io.oft, (entry % 8) * 8) #E
io.insert_int(0, io.oft, (entry % 8) * 8 + 4) #E
return 0
return 1