return slice(from, length)
end
- # Returns self as a hexadecimal digest
+ # Returns self as an hexadecimal digest.
+ #
+ # Also known as plain hexdump or postscript hexdump.
+ #
+ # ~~~
+ # var b = "abcd".to_bytes
+ # assert b.hexdigest == "61626364"
+ # assert b.hexdigest.hexdigest_to_bytes == b
+ # ~~~
fun hexdigest: String do
var elen = length * 2
var ns = new NativeString(elen)
return new FlatString.full(ns, elen, 0, elen)
end
+ # Return self as a C hexadecimal digest where bytes are prefixed by `\x`
+ #
+ # The output is compatible with literal stream of bytes for most languages
+ # including C and Nit.
+ #
+ # ~~~
+ # var b = "abcd".to_bytes
+ # assert b.chexdigest == "\\x61\\x62\\x63\\x64"
+ # assert b.chexdigest.unescape_to_bytes == b
+ # ~~~
+ fun chexdigest: String do
+ var elen = length * 4
+ var ns = new NativeString(elen)
+ var i = 0
+ var oi = 0
+ while i < length do
+ ns[oi] = 0x5Cu8 # b'\\'
+ ns[oi+1] = 0x78u8 # b'x'
+ self[i].add_digest_at(ns, oi+2)
+ i += 1
+ oi += 4
+ end
+ return new FlatString.full(ns, elen, 0, elen)
+ end
+
+
+ # Returns self as a stream of bits (0 and 1)
+ #
+ # ~~~
+ # var b = "abcd".to_bytes
+ # assert b.binarydigest == "01100001011000100110001101100100"
+ # assert b.binarydigest.binarydigest_to_bytes == b
+ # ~~~
+ fun binarydigest: String do
+ var elen = length * 8
+ var ns = new NativeString(elen)
+ var i = 0
+ var oi = 0
+ while i < length do
+ var c = self[i]
+ var b = 128u8
+ while b > 0u8 do
+ if c & b == 0u8 then
+ ns[oi] = 0x30u8 # b'0'
+ else
+ ns[oi] = 0x31u8 # b'1'
+ end
+ oi += 1
+ b = b >> 1
+ end
+ i += 1
+ end
+ return new FlatString.full(ns, elen, 0, elen)
+ end
+
+ # Interprets `self` as a big-endian positive integer.
+ #
+ # ~~~
+ # var b = "0102".hexdigest_to_bytes
+ # assert b.to_i == 258
+ # ~~~
+ #
+ # Nul bytes on the left are trimmed.
+ # 0 is returned for an empty Bytes object.
+ #
+ # ~~~
+ # assert "01".hexdigest_to_bytes.to_i == 1
+ # assert "0001".hexdigest_to_bytes.to_i == 1
+ #
+ # assert "0000".hexdigest_to_bytes.to_i == 0
+ # assert "00".hexdigest_to_bytes.to_i == 0
+ # assert "".hexdigest_to_bytes.to_i == 0
+ # ~~~
+ #
+ # `Int::to_bytes` is a loosely reverse method.
+ #
+ # ~~~
+ # assert b.to_i.to_bytes == b
+ # assert (b.to_i + 1).to_bytes.hexdigest == "0103"
+ # assert "0001".hexdigest_to_bytes.to_i.to_bytes.hexdigest == "01"
+ # ~~~
+ #
+ # Warning: `Int` might overflow for bytes with more than 60 bits.
+ fun to_i: Int do
+ var res = 0
+ var i = 0
+ while i < length do
+ res *= 256
+ res += self[i].to_i
+ i += 1
+ end
+ return res
+ end
+
# var b = new Bytes.with_capacity(1)
# b[0] = 101u8
# assert b.to_s == "e"
# Appends the bytes of `s` to `selftextextt`
fun append_text(s: Text) do
for i in s.substrings do
- append_ns(i.fast_cstring, i.bytelen)
+ append_ns(i.fast_cstring, i.byte_length)
end
end
redef fun item do return tgt[index]
end
+redef class Int
+ # A big-endian representation of self.
+ #
+ # ~~~
+ # assert 1.to_bytes.hexdigest == "01"
+ # assert 255.to_bytes.hexdigest == "FF"
+ # assert 256.to_bytes.hexdigest == "0100"
+ # assert 65535.to_bytes.hexdigest == "FFFF"
+ # assert 65536.to_bytes.hexdigest == "010000"
+ # ~~~
+ #
+ # For 0, a Bytes object with single nul byte is returned (instead of an empty Bytes object).
+ #
+ # ~~~
+ # assert 0.to_bytes.hexdigest == "00"
+ # ~~~
+ #
+ # `Bytes::to_i` can be used to do the reverse operation.
+ #
+ # ~~~
+ # assert 1234.to_bytes.to_i == 1234
+ # ~~~
+ #
+ # Require self >= 0
+ fun to_bytes: Bytes do
+ if self == 0 then return "\0".to_bytes
+ assert self > 0
+
+ # Compute the len (log256)
+ var len = 1
+ var max = 256
+ while self >= max do
+ len += 1
+ max *= 256
+ end
+
+ # Allocate the buffer
+ var res = new Bytes.with_capacity(len)
+ for i in [0..len[ do res[i] = 0u8
+
+ # Fill it starting with the end
+ var i = len
+ var sum = self
+ while i > 0 do
+ i -= 1
+ res[i] = (sum % 256).to_b
+ sum /= 256
+ end
+ return res
+ end
+end
+
redef class Text
# Returns a mutable copy of `self`'s bytes
#
# assert "String".to_bytes == [83u8, 116u8, 114u8, 105u8, 110u8, 103u8]
# ~~~
fun to_bytes: Bytes do
- var b = new Bytes.with_capacity(bytelen)
+ var b = new Bytes.with_capacity(byte_length)
append_to_bytes b
return b
end
fun append_to_bytes(b: Bytes) do
for s in substrings do
var from = if s isa FlatString then s.first_byte else 0
- b.append_ns_from(s.items, s.bytelen, from)
+ b.append_ns_from(s.items, s.byte_length, from)
end
end
# Returns a new `Bytes` instance with the digest as content
#
# assert "0B1F4D".hexdigest_to_bytes == [0x0Bu8, 0x1Fu8, 0x4Du8]
+ # assert "0B1F4D".hexdigest_to_bytes.hexdigest == "0B1F4D"
#
- # REQUIRE: `self` is a valid hexdigest and hexdigest.length % 2 == 0
+ # Characters that are not hexadecimal digits are ignored.
+ #
+ # assert "z0B1 F4\nD".hexdigest_to_bytes.hexdigest == "0B1F4D"
+ # assert "\\x0b1 \\xf4d".hexdigest_to_bytes.hexdigest == "0B1F4D"
+ #
+ # When the number of hexadecimal digit is not even, then a leading 0 is
+ # implicitly considered to fill the left byte (the most significant one).
+ #
+ # assert "1".hexdigest_to_bytes.hexdigest == "01"
+ # assert "FFF".hexdigest_to_bytes.hexdigest == "0FFF"
+ #
+ # `Bytes::hexdigest` is a loosely reverse method since its
+ # results contain only pairs of uppercase hexadecimal digits.
+ #
+ # assert "ABCD".hexdigest_to_bytes.hexdigest == "ABCD"
+ # assert "a b c".hexdigest_to_bytes.hexdigest == "0ABC"
fun hexdigest_to_bytes: Bytes do
var b = bytes
+ var max = byte_length
+
+ var dlength = 0 # Number of hex digits
var pos = 0
- var max = bytelen
- var ret = new Bytes.with_capacity(max / 2)
while pos < max do
- ret.add((b[pos].hexdigit_to_byteval << 4) |
- b[pos + 1].hexdigit_to_byteval)
- pos += 2
+ var c = b[pos]
+ if c.is_valid_hexdigit then dlength += 1
+ pos += 1
+ end
+
+ # Allocate the result buffer
+ var ret = new Bytes.with_capacity((dlength+1) / 2)
+
+ var i = (dlength+1) % 2 # current hex digit (1=high, 0=low)
+ var byte = 0u8 # current accumulated byte value
+
+ pos = 0
+ while pos < max do
+ var c = b[pos]
+ if c.is_valid_hexdigit then
+ byte = byte << 4 | c.hexdigit_to_byteval
+ i -= 1
+ if i < 0 then
+ # Last digit known: store and restart
+ ret.add byte
+ i = 1
+ byte = 0u8
+ end
+ end
+ pos += 1
end
return ret
end
#
# assert "<STRING/&rt;".hexdigest == "266C743B535452494E47262334373B2672743B"
fun hexdigest: String do
- var ln = bytelen
+ var ln = byte_length
var outns = new NativeString(ln * 2)
var oi = 0
for i in [0 .. ln[ do
# Return a `Bytes` instance where Nit escape sequences are transformed.
#
# assert "B\\n\\x41\\u0103D3".unescape_to_bytes.hexdigest == "420A41F0908F93"
+ #
+ # `Bytes::chexdigest` is a loosely reverse methods since its result is only made
+ # of `"\x??"` escape sequences.
+ #
+ # assert "\\x41\\x42\\x43".unescape_to_bytes.chexdigest == "\\x41\\x42\\x43"
+ # assert "B\\n\\x41\\u0103D3".unescape_to_bytes.chexdigest == "\\x42\\x0A\\x41\\xF0\\x90\\x8F\\x93"
fun unescape_to_bytes: Bytes do
- var res = new Bytes.with_capacity(self.bytelen)
+ var res = new Bytes.with_capacity(self.byte_length)
var was_slash = false
var i = 0
while i < length do
end
return res
end
+
+ # Return a `Bytes` by reading 0 and 1.
+ #
+ # assert "1010101100001101".binarydigest_to_bytes.hexdigest == "AB0D"
+ #
+ # Note that characters that are neither 0 or 1 are just ignored.
+ #
+ # assert "a1B01 010\n1100あ001101".binarydigest_to_bytes.hexdigest == "AB0D"
+ # assert "hello".binarydigest_to_bytes.is_empty
+ #
+ # When the number of bits is not divisible by 8, then leading 0 are
+ # implicitly considered to fill the left byte (the most significant one).
+ #
+ # assert "1".binarydigest_to_bytes.hexdigest == "01"
+ # assert "1111111".binarydigest_to_bytes.hexdigest == "7F"
+ # assert "1000110100".binarydigest_to_bytes.hexdigest == "0234"
+ #
+ # `Bytes::binarydigest` is a loosely reverse method since its
+ # results contain only 1 and 0 by blocks of 8.
+ #
+ # assert "1010101100001101".binarydigest_to_bytes.binarydigest == "1010101100001101"
+ # assert "1".binarydigest_to_bytes.binarydigest == "00000001"
+ fun binarydigest_to_bytes: Bytes
+ do
+ var b = bytes
+ var max = byte_length
+
+ # Count bits
+ var bitlen = 0
+ var pos = 0
+ while pos < max do
+ var c = b[pos]
+ pos += 1
+ if c == 0x30u8 or c == 0x31u8 then bitlen += 1 # b'0' or b'1'
+ end
+
+ # Allocate (and take care of the padding)
+ var ret = new Bytes.with_capacity((bitlen+7) / 8)
+
+ var i = (bitlen+7) % 8 # current bit (7th=128, 0th=1)
+ var byte = 0u8 # current accumulated byte value
+
+ pos = 0
+ while pos < max do
+ var c = b[pos]
+ pos += 1
+ if c == 0x30u8 then # b'0'
+ byte = byte << 1
+ else if c == 0x31u8 then # b'1'
+ byte = byte << 1 | 1u8
+ else
+ continue
+ end
+
+ i -= 1
+ if i < 0 then
+ # Last bit known: store and restart
+ ret.add byte
+ i = 7
+ byte = 0u8
+ end
+ end
+ return ret
+ end
end
redef class FlatText
redef fun append_to_bytes(b) do
var from = if self isa FlatString then first_byte else 0
- b.append_ns_from(items, bytelen, from)
+ b.append_ns_from(items, byte_length, from)
end
end
nitlanguage / nit.git / blobdiff