[coe.git] / coe / bin.py

import io, math
from . import data

T_END = 0
T_INT = 1
T_STR = 2
T_BIT = 3
T_NIL = 4
T_SYM = 5
T_CON = 6

INT_REF = 1

STR_SYM = 1

BIT_BFLOAT = 1
BIT_DFLOAT = 2

CON_SEQ = 0
CON_SET = 1
CON_MAP = 2
CON_OBJ = 3

NIL_FALSE = 1
NIL_TRUE = 2

class encoder(object):
    def __init__(self, *, backrefs=True):
        self.backrefs = backrefs
        self.reftab = {}
        self.nextref = 0
        self.nstab = {}

    @staticmethod
    def enctag(pri, sec):
        return bytes([(sec << 3) | pri])

    def writetag(self, dst, pri, sec, datum):
        dst.write(self.enctag(pri, sec))
        if self.backrefs:
            ref = self.nextref
            self.nextref += 1
            if datum is not None and id(datum) not in self.reftab:
                self.reftab[id(datum)] = ref
            return ref
        return None

    @staticmethod
    def encint(x):
        ret = bytearray()
        if x >= 0:
            b = x & 0x7f
            x >>= 7
            while (x > 0) or (b & 0x40) != 0:
                ret.append(0x80 | b)
                b = x & 0x7f
                x >>= 7
            ret.append(b)
        elif x < 0:
            b = x & 0x7f
            x >>= 7
            while x < -1 or (b & 0x40) == 0:
                ret.append(0x80 | b)
                b = x & 0x7f
                x >>= 7
            ret.append(b)
        return ret

    @staticmethod
    def writestr(dst, text):
        dst.write(text.encode("utf-8"))
        dst.write(b'\0')

    @staticmethod
    def writefloat(dst, x):
        if x == 0.0:
            mnt, exp = (0, 0)
        elif math.isinf(x):
            if x > 0:
                mnt, exp = (0, 2)
            else:
                mnt, exp = (0, 3)
        elif math.isnan(x):
            mnt, exp = (0, 4)
        else:
            mnt, exp = math.frexp(x)
            mnt *= 2
            exp -= 1
            while mnt != int(mnt):
                mnt *= 2
            mnt = int(mnt)
        buf = bytearray()
        buf.extend(encoder.encint(mnt))
        buf.extend(encoder.encint(exp))
        dst.write(encoder.encint(len(buf)))
        dst.write(buf)

    def dumpseq(self, dst, seq):
        for v in seq:
            self.dump(dst, v)
        dst.write(self.enctag(T_END, 0))

    def dumpmap(self, dst, val):
        for k, v in val.items():
            self.dump(dst, k)
            self.dump(dst, v)
        dst.write(self.enctag(T_END, 0))

    def dump(self, dst, datum):
        ref = self.reftab.get(id(datum))
        if ref is not None:
            dst.write(self.enctag(T_INT, INT_REF))
            dst.write(self.encint(ref))
            return
        if datum == None:
            self.writetag(dst, T_NIL, 0, None)
        elif datum is False:
            self.writetag(dst, T_NIL, NIL_FALSE, None)
        elif datum is True:
            self.writetag(dst, T_NIL, NIL_TRUE, None)
        elif isinstance(datum, int):
            self.writetag(dst, T_INT, 0, None)
            dst.write(self.encint(datum))
        elif isinstance(datum, str):
            self.writetag(dst, T_STR, 0, datum)
            self.writestr(dst, datum)
        elif isinstance(datum, (bytes, bytearray)):
            self.writetag(dst, T_BIT, 0, datum)
            dst.write(self.encint(len(datum)))
            dst.write(datum)
        elif isinstance(datum, float):
            self.writetag(dst, T_BIT, BIT_BFLOAT, datum)
            self.writefloat(dst, datum)
        elif isinstance(datum, data.symbol):
            if datum.ns == "":
                self.writetag(dst, T_STR, STR_SYM, datum)
                self.writestr(dst, datum.name)
            else:
                nsref = self.nstab.get(datum.ns)
                if nsref is None:
                    nsref = self.writetag(dst, T_SYM, 0, datum)
                    dst.write(b'\0')
                    self.writestr(dst, datum.ns)
                    self.writestr(dst, datum.name)
                    if nsref is not None:
                        self.nstab[datum.ns] = nsref
                else:
                    self.writetag(dst, T_SYM, 0, datum)
                    dst.write(b'\x01')
                    dst.write(self.encint(nsref))
                    self.writestr(dst, datum.name)
        elif isinstance(datum, list):
            self.writetag(dst, T_CON, CON_SEQ, datum)
            self.dumpseq(dst, datum)
        elif isinstance(datum, set):
            self.writetag(dst, T_CON, CON_SET, datum)
            self.dumpseq(dst, datum)
        elif isinstance(datum, dict):
            self.writetag(dst, T_CON, CON_MAP, datum)
            self.dumpmap(dst, datum)
        elif isinstance(datum, data.obj):
            self.writetag(dst, T_CON, CON_OBJ, datum)
            self.dump(dst, getattr(type(datum), "typename", None))
            self.dumpmap(dst, datum.__dict__)
        else:
            raise ValueError("unsupported object type: " + repr(datum))

def dump(dst, datum):
    encoder().dump(dst, datum)
    return dst

class fmterror(Exception):
    pass

class eoferror(fmterror):
    def __init__(self):
        super().__init__("unexpected end-of-data")

class referror(fmterror):
    def __init__(self):
        super().__init__("bad backref")

class decoder(object):
    def __init__(self):
        self.reftab = []
        self.namedtypes = {}

    @staticmethod
    def byte(fp):
        b = fp.read(1)
        if b == b"":
            raise eoferror()
        return b[0]

    @staticmethod
    def loadint(fp):
        ret = 0
        p = 0
        while True:
            b = decoder.byte(fp)
            ret += (b & 0x7f) << p
            p += 7
            if (b & 0x80) == 0:
                break
        if (b & 0x40) != 0:
            ret = ret - (1 << p)
        return ret

    @staticmethod
    def loadstr(fp):
        buf = bytearray()
        while True:
            b = decoder.byte(fp)
            if b == 0:
                break
            buf.append(b)
        return buf.decode("utf-8")

    def loadsym(self, fp):
        h = self.byte(fp)
        if h & 0x1:
            nsref = self.loadint(fp)
            if not 0 <= nsref < len(self.reftab):
                raise fmterror("illegal namespace ref: " + str(nsref))
            nssym = self.reftab[nsref]
            if not isinstance(nssym, data.symbol):
                raise fmterror("illegal namespace ref: " + str(nsref))
            ns = nssym.ns
        else:
            ns = self.loadstr(fp)
        nm = self.loadstr(fp)
        ret = data.symbol.get(ns, nm)
        return ret

    def loadlist(self, fp, buf):
        while True:
            tag = self.byte(fp)
            if tag == T_END:
                return buf
            buf.append(self.loadtagged(fp, tag))

    def loadmap(self, fp, buf):
        while True:
            tag = self.byte(fp)
            if tag == T_END:
                return buf
            key = self.loadtagged(fp, tag)
            tag = self.byte(fp)
            if tag == T_END:
                return buf
            buf[key] = self.loadtagged(fp, tag)

    def makeobjtype(self, nm):
        return data.namedtype.make(str(nm), (data.obj, object), {}, typename=nm)

    def loadobj(self, fp, ref=False):
        if ref:
            refid = len(self.reftab)
            self.reftab.append(None)
        nm = self.load(fp)
        typ = self.namedtypes.get(nm)
        if typ is None:
            typ = self.namedtypes[nm] = self.makeobjtype(nm)
        ret = typ()
        if ref:
            self.reftab[refid] = ret
        # st = fp.tell()
        # print(">", nm, hex(st))
        ret.__dict__.update(self.loadmap(fp, {}))
        # print("<", nm, hex(fp.tell()), hex(st))
        return ret

    def addref(self, obj):
        self.reftab.append(obj)
        return obj

    def loadtagged(self, fp, tag):
        pri, sec = (tag & 0x7), (tag & 0xf8) >> 3
        if pri == T_END:
            raise fmterror("unexpected end-tag")
        elif pri == T_INT:
            if sec == INT_REF:
                idx = self.loadint(fp)
                if not 0 <= idx < len(self.reftab):
                    raise referror()
                # print(idx, self.reftab[idx], hex(fp.tell()))
                return self.reftab[idx]
            return self.addref(self.loadint(fp))
        elif pri == T_STR:
            ret = self.loadstr(fp)
            if sec == STR_SYM:
                return self.addref(data.symbol.get("", ret))
            return self.addref(ret)
        elif pri == T_BIT:
            ln = self.loadint(fp)
            ret = fp.read(ln)
            if len(ret) < ln:
                raise eoferror()
            if sec == BIT_BFLOAT:
                buf = io.BytesIO(ret)
                mnt = self.loadint(buf)
                exp = self.loadint(buf)
                if mnt == 0:
                    if exp == 0:
                        return 0.0
                    elif exp == 1:
                        return -0.0
                    elif exp == 2:
                        return float("inf")
                    elif exp == 3:
                        return -float("inf")
                    else:
                        return float("nan")
                else:
                    ret = math.ldexp(mnt, exp - (mnt.bit_length() - 1))
                return self.addref(ret)
            return self.addref(ret)
        elif pri == T_NIL:
            if sec == NIL_TRUE:
                return self.addref(True)
            elif sec == NIL_FALSE:
                return self.addref(False)
            return self.addref(None)
        elif pri == T_SYM:
            return self.addref(self.loadsym(fp))
        elif pri == T_CON:
            if sec == CON_MAP:
                return self.loadmap(fp, self.addref({}))
            elif sec == CON_OBJ:
                return self.loadobj(fp, ref=True)
            else:
                return self.loadlist(fp, self.addref([]))
        else:
            raise fmterror("unknown primary: " + str(pri))

    def load(self, fp):
        tag = self.byte(fp)
        return self.loadtagged(fp, tag)

def load(fp):
    return decoder().load(fp)
Commit	Line	Data
	1	import io, math
	2	from . import data
	3
	4	T_END = 0
	5	T_INT = 1
	6	T_STR = 2
	7	T_BIT = 3
	8	T_NIL = 4
	9	T_SYM = 5
	10	T_CON = 6
	11
	12	INT_REF = 1
	13
	14	STR_SYM = 1
	15
	16	BIT_BFLOAT = 1
	17	BIT_DFLOAT = 2
	18
	19	CON_SEQ = 0
	20	CON_SET = 1
	21	CON_MAP = 2
	22	CON_OBJ = 3
	23
	24	NIL_FALSE = 1
	25	NIL_TRUE = 2
	26
	27	class encoder(object):
	28	def __init__(self, *, backrefs=True):
	29	self.backrefs = backrefs
	30	self.reftab = {}
	31	self.nextref = 0
	32	self.nstab = {}
	33
	34	@staticmethod
	35	def enctag(pri, sec):
	36	return bytes([(sec << 3) \| pri])
	37
	38	def writetag(self, dst, pri, sec, datum):
	39	dst.write(self.enctag(pri, sec))
	40	if self.backrefs:
	41	ref = self.nextref
	42	self.nextref += 1
	43	if datum is not None and id(datum) not in self.reftab:
	44	self.reftab[id(datum)] = ref
	45	return ref
	46	return None
	47
	48	@staticmethod
	49	def encint(x):
	50	ret = bytearray()
	51	if x >= 0:
	52	b = x & 0x7f
	53	x >>= 7
	54	while (x > 0) or (b & 0x40) != 0:
	55	ret.append(0x80 \| b)
	56	b = x & 0x7f
	57	x >>= 7
	58	ret.append(b)
	59	elif x < 0:
	60	b = x & 0x7f
	61	x >>= 7
	62	while x < -1 or (b & 0x40) == 0:
	63	ret.append(0x80 \| b)
	64	b = x & 0x7f
	65	x >>= 7
	66	ret.append(b)
	67	return ret
	68
	69	@staticmethod
	70	def writestr(dst, text):
	71	dst.write(text.encode("utf-8"))
	72	dst.write(b'\0')
	73
	74	@staticmethod
	75	def writefloat(dst, x):
	76	if x == 0.0:
	77	mnt, exp = (0, 0)
	78	elif math.isinf(x):
	79	if x > 0:
	80	mnt, exp = (0, 2)
	81	else:
	82	mnt, exp = (0, 3)
	83	elif math.isnan(x):
	84	mnt, exp = (0, 4)
	85	else:
	86	mnt, exp = math.frexp(x)
	87	mnt *= 2
	88	exp -= 1
	89	while mnt != int(mnt):
	90	mnt *= 2
	91	mnt = int(mnt)
	92	buf = bytearray()
	93	buf.extend(encoder.encint(mnt))
	94	buf.extend(encoder.encint(exp))
	95	dst.write(encoder.encint(len(buf)))
	96	dst.write(buf)
	97
	98	def dumpseq(self, dst, seq):
	99	for v in seq:
	100	self.dump(dst, v)
	101	dst.write(self.enctag(T_END, 0))
	102
	103	def dumpmap(self, dst, val):
	104	for k, v in val.items():
	105	self.dump(dst, k)
	106	self.dump(dst, v)
	107	dst.write(self.enctag(T_END, 0))
	108
	109	def dump(self, dst, datum):
	110	ref = self.reftab.get(id(datum))
	111	if ref is not None:
	112	dst.write(self.enctag(T_INT, INT_REF))
	113	dst.write(self.encint(ref))
	114	return
	115	if datum == None:
	116	self.writetag(dst, T_NIL, 0, None)
	117	elif datum is False:
	118	self.writetag(dst, T_NIL, NIL_FALSE, None)
	119	elif datum is True:
	120	self.writetag(dst, T_NIL, NIL_TRUE, None)
	121	elif isinstance(datum, int):
	122	self.writetag(dst, T_INT, 0, None)
	123	dst.write(self.encint(datum))
	124	elif isinstance(datum, str):
	125	self.writetag(dst, T_STR, 0, datum)
	126	self.writestr(dst, datum)
	127	elif isinstance(datum, (bytes, bytearray)):
	128	self.writetag(dst, T_BIT, 0, datum)
	129	dst.write(self.encint(len(datum)))
	130	dst.write(datum)
	131	elif isinstance(datum, float):
	132	self.writetag(dst, T_BIT, BIT_BFLOAT, datum)
	133	self.writefloat(dst, datum)
	134	elif isinstance(datum, data.symbol):
	135	if datum.ns == "":
	136	self.writetag(dst, T_STR, STR_SYM, datum)
	137	self.writestr(dst, datum.name)
	138	else:
	139	nsref = self.nstab.get(datum.ns)
	140	if nsref is None:
	141	nsref = self.writetag(dst, T_SYM, 0, datum)
	142	dst.write(b'\0')
	143	self.writestr(dst, datum.ns)
	144	self.writestr(dst, datum.name)
	145	if nsref is not None:
	146	self.nstab[datum.ns] = nsref
	147	else:
	148	self.writetag(dst, T_SYM, 0, datum)
	149	dst.write(b'\x01')
	150	dst.write(self.encint(nsref))
	151	self.writestr(dst, datum.name)
	152	elif isinstance(datum, list):
	153	self.writetag(dst, T_CON, CON_SEQ, datum)
	154	self.dumpseq(dst, datum)
	155	elif isinstance(datum, set):
	156	self.writetag(dst, T_CON, CON_SET, datum)
	157	self.dumpseq(dst, datum)
	158	elif isinstance(datum, dict):
	159	self.writetag(dst, T_CON, CON_MAP, datum)
	160	self.dumpmap(dst, datum)
	161	elif isinstance(datum, data.obj):
	162	self.writetag(dst, T_CON, CON_OBJ, datum)
	163	self.dump(dst, getattr(type(datum), "typename", None))
	164	self.dumpmap(dst, datum.__dict__)
	165	else:
	166	raise ValueError("unsupported object type: " + repr(datum))
	167
	168	def dump(dst, datum):
	169	encoder().dump(dst, datum)
	170	return dst
	171
	172	class fmterror(Exception):
	173	pass
	174
	175	class eoferror(fmterror):
	176	def __init__(self):
	177	super().__init__("unexpected end-of-data")
	178
	179	class referror(fmterror):
	180	def __init__(self):
	181	super().__init__("bad backref")
	182
	183	class decoder(object):
	184	def __init__(self):
	185	self.reftab = []
	186	self.namedtypes = {}
	187
	188	@staticmethod
	189	def byte(fp):
	190	b = fp.read(1)
	191	if b == b"":
	192	raise eoferror()
	193	return b[0]
	194
	195	@staticmethod
	196	def loadint(fp):
	197	ret = 0
	198	p = 0
	199	while True:
	200	b = decoder.byte(fp)
	201	ret += (b & 0x7f) << p
	202	p += 7
	203	if (b & 0x80) == 0:
	204	break
	205	if (b & 0x40) != 0:
	206	ret = ret - (1 << p)
	207	return ret
	208
	209	@staticmethod
	210	def loadstr(fp):
	211	buf = bytearray()
	212	while True:
	213	b = decoder.byte(fp)
	214	if b == 0:
	215	break
	216	buf.append(b)
	217	return buf.decode("utf-8")
	218
	219	def loadsym(self, fp):
	220	h = self.byte(fp)
	221	if h & 0x1:
	222	nsref = self.loadint(fp)
	223	if not 0 <= nsref < len(self.reftab):
	224	raise fmterror("illegal namespace ref: " + str(nsref))
	225	nssym = self.reftab[nsref]
	226	if not isinstance(nssym, data.symbol):
	227	raise fmterror("illegal namespace ref: " + str(nsref))
	228	ns = nssym.ns
	229	else:
	230	ns = self.loadstr(fp)
	231	nm = self.loadstr(fp)
	232	ret = data.symbol.get(ns, nm)
	233	return ret
	234
	235	def loadlist(self, fp, buf):
	236	while True:
	237	tag = self.byte(fp)
	238	if tag == T_END:
	239	return buf
	240	buf.append(self.loadtagged(fp, tag))
	241
	242	def loadmap(self, fp, buf):
	243	while True:
	244	tag = self.byte(fp)
	245	if tag == T_END:
	246	return buf
	247	key = self.loadtagged(fp, tag)
	248	tag = self.byte(fp)
	249	if tag == T_END:
	250	return buf
	251	buf[key] = self.loadtagged(fp, tag)
	252
	253	def makeobjtype(self, nm):
	254	return data.namedtype.make(str(nm), (data.obj, object), {}, typename=nm)
	255
	256	def loadobj(self, fp, ref=False):
	257	if ref:
	258	refid = len(self.reftab)
	259	self.reftab.append(None)
	260	nm = self.load(fp)
	261	typ = self.namedtypes.get(nm)
	262	if typ is None:
	263	typ = self.namedtypes[nm] = self.makeobjtype(nm)
	264	ret = typ()
	265	if ref:
	266	self.reftab[refid] = ret
	267	# st = fp.tell()
	268	# print(">", nm, hex(st))
	269	ret.__dict__.update(self.loadmap(fp, {}))
	270	# print("<", nm, hex(fp.tell()), hex(st))
	271	return ret
	272
	273	def addref(self, obj):
	274	self.reftab.append(obj)
	275	return obj
	276
	277	def loadtagged(self, fp, tag):
	278	pri, sec = (tag & 0x7), (tag & 0xf8) >> 3
	279	if pri == T_END:
	280	raise fmterror("unexpected end-tag")
	281	elif pri == T_INT:
	282	if sec == INT_REF:
	283	idx = self.loadint(fp)
	284	if not 0 <= idx < len(self.reftab):
	285	raise referror()
	286	# print(idx, self.reftab[idx], hex(fp.tell()))
	287	return self.reftab[idx]
	288	return self.addref(self.loadint(fp))
	289	elif pri == T_STR:
	290	ret = self.loadstr(fp)
	291	if sec == STR_SYM:
	292	return self.addref(data.symbol.get("", ret))
	293	return self.addref(ret)
	294	elif pri == T_BIT:
	295	ln = self.loadint(fp)
	296	ret = fp.read(ln)
	297	if len(ret) < ln:
	298	raise eoferror()
	299	if sec == BIT_BFLOAT:
	300	buf = io.BytesIO(ret)
	301	mnt = self.loadint(buf)
	302	exp = self.loadint(buf)
	303	if mnt == 0:
	304	if exp == 0:
	305	return 0.0
	306	elif exp == 1:
	307	return -0.0
	308	elif exp == 2:
	309	return float("inf")
	310	elif exp == 3:
	311	return -float("inf")
	312	else:
	313	return float("nan")
	314	else:
	315	ret = math.ldexp(mnt, exp - (mnt.bit_length() - 1))
	316	return self.addref(ret)
	317	return self.addref(ret)
	318	elif pri == T_NIL:
	319	if sec == NIL_TRUE:
	320	return self.addref(True)
	321	elif sec == NIL_FALSE:
	322	return self.addref(False)
	323	return self.addref(None)
	324	elif pri == T_SYM:
	325	return self.addref(self.loadsym(fp))
	326	elif pri == T_CON:
	327	if sec == CON_MAP:
	328	return self.loadmap(fp, self.addref({}))
	329	elif sec == CON_OBJ:
	330	return self.loadobj(fp, ref=True)
	331	else:
	332	return self.loadlist(fp, self.addref([]))
	333	else:
	334	raise fmterror("unknown primary: " + str(pri))
	335
	336	def load(self, fp):
	337	tag = self.byte(fp)
	338	return self.loadtagged(fp, tag)
	339
	340	def load(fp):
	341	return decoder().load(fp)