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def LEB128UnsignedDecode(bytelist):
result = 0
shift = 0
for byte in bytelist:
result |= (byte & 0x7f) << shift
if (byte & 0x80) == 0:
break
shift += 7
return(result)
def LEB128SignedDecode(bytelist):
result = 0
shift = 0
for byte in bytelist:
result |= (byte & 0x7f) << shift
last_byte = byte
shift += 7
if (byte & 0x80) == 0:
break
if last_byte & 0x40:
result |= - (1 << shift)
return(result)
def LEB128UnsignedEncode(int_val):
if int_val < 0:
raise Exception("value must not be negative")
elif int_val == 0:
return bytes([0])
byte_array = bytearray()
while int_val:
byte = int_val & 0x7f
byte_array.append(byte | 0x80)
int_val >>= 7
byte_array[-1] ^= 0x80
return(byte_array)
def LEB128SignedEncode(int_val):
byte_array = bytearray()
while True:
byte = int_val & 0x7f
byte_array.append(byte | 0x80)
int_val >>= 7
if (int_val == 0 and byte&0x40 == 0) or (int_val == -1 and byte&0x40):
byte_array[-1] ^= 0x80
break
return(byte_array)
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