Copy Link
Add to Bookmark
Report
NULL mag Issue 06 20 Access a jam base with python
as i am learning python, i made this simple lib/program to read a JAM
base. it can read the header file and also read info/text from a
message. for sure i will evolve it and make it even better, but for
the purposes of the mag, is enough for now. just change the file name
of the jam base and test it yourself.
you can use it freely. u can read message text and make all sort of
things with it, in your projects.
python is a "universal" programming language now days, so expect more
things written in python also.
--- cut here ---------------------------------------------------------------
#!/usr/bin/python3
import struct
from datetime import datetime
import os
jam_local = int('00000001',16)
jam_intransit = int('00000002',16)
jam_priv = int('00000004',16)
jam_rcvd = int('00000008',16)
jam_sent = int('00000010',16)
jam_killsent = int('00000020',16)
jam_achvsent = int('00000040',16)
jam_hold = int('00000080',16)
jam_crash = int('00000100',16)
jam_imm = int('00000200',16)
jam_direct = int('00000400',16)
jam_gate = int('00000800',16)
jam_freq = int('00001000',16)
jam_fattch = int('00002000',16)
jam_truncfile = int('00004000',16)
jam_killfile = int('00008000',16)
jam_rcptreq = int('00010000',16)
jam_confmreq = int('00020000',16)
jam_orphan = int('00040000',16)
jam_encrypt = int('00080000',16)
jam_compress = int('00100000',16)
jam_escaped = int('00200000',16)
jam_fpu = int('00400000',16)
jam_typelocal = int('00800000',16)
jam_typeecho = int('01000000',16)
jam_typenet = int('02000000',16)
jam_nodisp = int('20000000',16)
jam_locked = int('40000000',16)
jam_deleted = int('80000000',16)
base_filename = ''
mbase_header=dict()
msg_header=dict()
# mbase_header["signature"]
# mbase_header["created"]
# mbase_header["modcounter"]
# mbase_header["activemsgs"]
# mbase_header["passwordcrc"]
# mbase_header["basemsgnum"]
#functions for msg attributes
def isdeleted():
global msg_header
if (jam_deleted & msg_header["attr1"] ) != 0:
return True
else:
return False
def islocal():
global msg_header
if (jam_local & msg_header["attr1"] ) != 0:
return True
else:
return False
def isreceived():
global msg_header
if (jam_rcvd & msg_header["attr1"] ) != 0:
return True
else:
return False
# read the header file and get info
# returns 0 if is succesful, -1 if file doesn't exist and -2 if file
# is not valid jam base
def get_msg_base_hdr(filename):
global mbase_header
global base_filename
base_filename = filename
filename = filename + '.jhr'
if os.path.exists(filename) == False:
return -1
jamf = "ssssIIIII"
with open(filename, mode='rb') as file:
fileMsgHdr = file.read(struct.calcsize(jamf))
jam_hdr = struct.unpack(jamf, fileMsgHdr[0:24])
mbase_header["signature"] = jam_hdr[:4]
mbase_header["created"] = \
datetime.fromtimestamp(jam_hdr[4]).strftime('%Y-%m-%d %H:%M:%S')
mbase_header["modcounter"] = jam_hdr[5]
mbase_header["activemsgs"] = jam_hdr[6]
mbase_header["passwordcrc"] = jam_hdr[7]
mbase_header["basemsgnum"] = jam_hdr[8]
if mbase_header["signature"] == (b'J', b'A', b'M', b'\x00'):
return 0
else:
return -2
# read the message header
def read_msg_header(filename,num):
global msg_header
global base_filename
base_filename = filename
jdx_name = filename + '.jdx' # get header offset from index file
if os.path.exists(jdx_name) == False:
return -1
jdx = open(jdx_name,"rb")
jdx_size = os.path.getsize(jdx_name)
offset = (num - mbase_header["basemsgnum"])*8
if offset>jdx_size:
jdx.close()
return -2
jdx.seek((num - mbase_header["basemsgnum"])*8)
jdxf = "<II"
jdxvalue = jdx.read(8)
jdxuser,jdxoffset = struct.unpack(jdxf,jdxvalue)
jdx.close()
jhr_name = filename + '.jhr'
jhr = open(jhr_name,"rb") # open header file
jhr.seek(jdxoffset) # seek header of specific msg
#debug string
#print('header offset: '+str(jdxoffset))
msgheaderf = "<4sHHIIIIIIIIIIIiIIIII"
msgheader = jhr.read(struct.calcsize (msgheaderf)) # read header
msg = struct.unpack(msgheaderf,msgheader)
#debug string
#print("header size: "+str(struct.calcsize (msgheaderf)))
msg_header["signature"] = msg[0]
msg_header["rev"] = msg[1]
msg_header["resvd"] = msg[2]
msg_header["subfieldlen"] = msg[3]
msg_header["timesread"] = msg[4]
msg_header["msgidcrc"] = msg[5]
msg_header["replycrc"] = msg[6]
msg_header["replyto"] = msg[7]
msg_header["replyfirst"] = msg[8]
msg_header["replynext"] = msg[9]
msg_header["datewritten"] = msg[10]
msg_header["datercvd"] = msg[11]
msg_header["datearrived"] = msg[12]
msg_header["msgnum"] = msg[13]
msg_header["attr1"] = msg[14]
msg_header["attr2"] = msg[15]
msg_header["textofs"] = msg[16]
msg_header["textlen"] = msg[17]
msg_header["pwdcrc"] = msg[18]
msg_header["cost"] = msg[19]
msg_header["origin"] = ''
msg_header["destination"] = ''
msg_header["sender"] = ''
msg_header["receiver"] = ''
msg_header["msgid"] = ''
msg_header["replyid"] = ''
msg_header["subject"] = ''
msg_header["pid"] = ''
msg_header["trace"] = ''
msg_header["kludge"] = ''
msg_header["seenby"] = ''
msg_header["path2d"] = ''
msg_header["flags"] = ''
msg_header["tzutc"] = ''
if msg_header["subfieldlen"] != 0:
#print(jdxoffset + struct.calcsize (msgheaderf) + msg_header["subfieldlen"]) while jhr.tell() <= jdxoffset + struct.calcsize (msgheaderf) + \
msg_header["subfieldlen"]:
loid = jhr.read(2)
loid = struct.unpack('<H',loid)
loid = loid[0]
hiid = jhr.read(2)
hiid = struct.unpack('<H',hiid)
hiid = hiid[0]
sflen = struct.unpack('<I',jhr.read(4))
buf = jhr.read(sflen[0])
#debug string
#print("tell: "+str(jhr.tell()))
if loid == 0:
msg_header["origin"] = ''.join(str(buf)).strip("b'")
elif loid == 1:
msg_header["destination"] = ''.join(str(buf)).strip("b'")
elif loid == 2:
msg_header["sender"] = ''.join(str(buf)).strip("b'")
elif loid == 3:
msg_header["receiver"] = ''.join(str(buf)).strip("b'")
elif loid == 4:
msg_header["msgid"] = ''.join(str(buf)).strip("b'")
elif loid == 5:
msg_header["replyid"] = ''.join(str(buf)).strip("b'")
elif loid == 6:
msg_header["subject"] = ''.join(str(buf)).strip("b'")
elif loid == 7:
msg_header["pid"] = ''.join(str(buf)).strip("b'")
elif loid == 8:
msg_header["trace"] = ''.join(str(buf)).strip("b'")
elif loid == 2000:
msg_header["kludge"] = ''.join(str(buf)).strip("b'")
elif loid == 2001:
msg_header["seenby"] = ''.join(str(buf)).strip("b'")
elif loid == 2002:
msg_header["path2d"] = ''.join(str(buf)).strip("b'")
elif loid == 2003:
msg_header["flags"] = buf
elif loid == 2004:
msg_header["tzutc"] = ''.join(str(buf)).strip("b'")
jhr.close()
return 0
# get the text of a message if msg is not deleted
def msg_read_text():
global base_filename
global msg_header
if not os.path.exists(base_filename+'.jdt'):
return -2
if isdeleted():
return -3
jdt = open(base_filename+'.jdt','rb')
print(msg_header["textofs"])
print(msg_header["textlen"])
jdt.seek(msg_header["textofs"])
res = jdt.read(msg_header["textlen"])
jdt.close()
res = ''.join(str(res,"cp437"))
res = "\n".join(res.splitlines())
return res
# convert unix time to string
def unix2str(dt):
return datetime.fromtimestamp(dt).strftime('%Y-%m-%d %H:%M:%S')
# example
# get the header of a base
if get_msg_base_hdr("./fsx_bbs") != 0:
print('file not found')
exit
# read header of message 1
read_msg_header("./fsx_bbs",1)
# print some info
print (msg_header["sender"])
print (msg_header["subject"])
print (msg_header["destination"])
print (msg_header["origin"])
print (msg_header["tzutc"])
# print text of msg
print(msg_read_text())
print("")
--- stop cut here ----------------------------------------------------------
--- admire here --------------------------------------------------------:P--
