import collection::array
intrude import text::flat
+# Any kind of entity which can be searched for in a Sequence of Byte
+interface BytePattern
+ # Return the first occurence of `self` in `b`, or -1 if not found
+ fun first_index_in(b: SequenceRead[Byte]): Int do return first_index_in_from(b, 0)
+
+ # Return the first occurence of `self` in `b` starting at `from`, or -1 if not found
+ fun first_index_in_from(b: SequenceRead[Byte], from: Int): Int is abstract
+
+ # Return the last occurence of `self` in `b`, or -1 if not found
+ fun last_index_in(b: SequenceRead[Byte]): Int do return last_index_in_from(b, b.length - 1)
+
+ # Return the last occurence of `self` in `b`, or -1 if not found
+ fun last_index_in_from(b: SequenceRead[Byte], from: Int): Int is abstract
+
+ # Returns the indexes of all the occurences of `self` in `b`
+ fun search_all_in(b: SequenceRead[Byte]): SequenceRead[Int] is abstract
+
+ # Length of the pattern
+ fun pattern_length: Int is abstract
+
+ # Appends `self` to `b`
+ fun append_to(b: Sequence[Byte]) is abstract
+
+ # Is `self` a prefix for `b` ?
+ fun is_prefix(b: SequenceRead[Byte]): Bool is abstract
+
+ # Is `self` a suffix for `b` ?
+ fun is_suffix(b: SequenceRead[Byte]): Bool is abstract
+end
+
redef class Byte
+ super BytePattern
+
# Write self as a string into `ns` at position `pos`
- private fun add_digest_at(ns: NativeString, pos: Int) do
+ private fun add_digest_at(ns: CString, pos: Int) do
var tmp = (0xF0u8 & self) >> 4
ns[pos] = if tmp >= 0x0Au8 then tmp + 0x37u8 else tmp + 0x30u8
tmp = 0x0Fu8 & self
# i.e. this abort is here to please the compiler
abort
end
+
+ redef fun first_index_in_from(b, from) do
+ for i in [from .. b.length[ do if b[i] == self then return i
+ return -1
+ end
+
+ redef fun last_index_in_from(b, from) do
+ for i in [0 .. from].step(-1) do if b[i] == self then return i
+ return -1
+ end
+
+ redef fun search_all_in(b) do
+ var ret = new Array[Int]
+ var pos = 0
+ loop
+ pos = first_index_in_from(b, pos)
+ if pos == -1 then return ret
+ ret.add pos
+ pos += 1
+ end
+ end
+
+ redef fun pattern_length do return 1
+
+ redef fun append_to(b) do b.push self
+
+ # assert 'b'.ascii.is_suffix("baqsdb".to_bytes)
+ # assert not 'b'.ascii.is_suffix("baqsd".to_bytes)
+ redef fun is_suffix(b) do return b.length != 0 and b.last == self
+
+ # assert 'b'.ascii.is_prefix("baqsdb".to_bytes)
+ # assert not 'b'.ascii.is_prefix("aqsdb".to_bytes)
+ redef fun is_prefix(b) do return b.length != 0 and b.first == self
end
# A buffer containing Byte-manipulation facilities
# Uses Copy-On-Write when persisted
class Bytes
super AbstractArray[Byte]
+ super BytePattern
- # A NativeString being a char*, it can be used as underlying representation here.
- var items: NativeString
+ # A CString being a char*, it can be used as underlying representation here.
+ var items: CString
# Number of bytes in the array
redef var length
# var b = new Bytes.empty
# assert b.to_s == ""
init empty do
- var ns = new NativeString(0)
+ var ns = new CString(0)
init(ns, 0, 0)
end
# Init a `Bytes` with capacity `cap`
init with_capacity(cap: Int) do
- var ns = new NativeString(cap)
+ var ns = new CString(cap)
init(ns, 0, cap)
end
- redef fun is_empty do return length != 0
+ redef fun pattern_length do return length
+
+ redef fun is_empty do return length == 0
# var b = new Bytes.empty
# b.add 101u8
return items[i]
end
- # Returns self as a hexadecimal digest
+ # Returns a copy of `self`
+ fun clone: Bytes do
+ var b = new Bytes.with_capacity(length)
+ b.append(self)
+ return b
+ end
+
+ # Trims off the whitespaces at the beginning and the end of `self`
+ #
+ # var b = "102041426E6F1020" .hexdigest_to_bytes
+ # assert b.trim.hexdigest == "41426E6F"
+ #
+ # NOTE: A whitespace is defined here as a byte whose value is <= 0x20
+ fun trim: Bytes do
+ var st = 0
+ while st < length do
+ if self[st] > 0x20u8 then break
+ st += 1
+ end
+ if st >= length then return new Bytes.empty
+ var ed = length - 1
+ while ed > 0 do
+ if self[ed] > 0x20u8 then break
+ ed -= 1
+ end
+ return slice(st, ed - st + 1)
+ end
+
+ # Copy a subset of `self` starting at `from` and of `count` bytes
+ #
+ # var b = "abcd".to_bytes
+ # assert b.slice(1, 2).hexdigest == "6263"
+ # assert b.slice(-1, 2).hexdigest == "61"
+ # assert b.slice(1, 0).hexdigest == ""
+ # assert b.slice(2, 5).hexdigest == "6364"
+ fun slice(from, count: Int): Bytes do
+ if count <= 0 then return new Bytes.empty
+
+ if from < 0 then
+ count += from
+ if count < 0 then count = 0
+ from = 0
+ end
+
+ if (count + from) > length then count = length - from
+ if count <= 0 then return new Bytes.empty
+
+ var ret = new Bytes.with_capacity(count)
+
+ ret.append_ns(items.fast_cstring(from), count)
+ return ret
+ end
+
+ # Copy of `self` starting at `from`
+ #
+ # var b = "abcd".to_bytes
+ # assert b.slice_from(1).hexdigest == "626364"
+ # assert b.slice_from(-1).hexdigest == "61626364"
+ # assert b.slice_from(2).hexdigest == "6364"
+ fun slice_from(from: Int): Bytes do
+ if from >= length then return new Bytes.empty
+ if from < 0 then from = 0
+ return slice(from, length)
+ end
+
+ # 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)
+ var ns = new CString(elen)
var i = 0
var oi = 0
while i < length do
i += 1
oi += 2
end
- return new FlatString.full(ns, elen, 0, elen - 1, 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 CString(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 CString(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 integer (unsigned by default)
+ #
+ # ~~~
+ # var b = "0102".hexdigest_to_bytes
+ # assert b.to_i == 258
+ #
+ # assert "01".hexdigest_to_bytes.to_i == 1
+ # assert "FF".hexdigest_to_bytes.to_i == 255
+ # assert "0000".hexdigest_to_bytes.to_i == 0
+ # ~~~
+ #
+ # If `self.is_empty`, 0 is returned.
+ #
+ # ~~~
+ # assert "".hexdigest_to_bytes.to_i == 0
+ # ~~~
+ #
+ # If `signed == true`, the bytes are read as a signed integer.
+ # As usual, the sign bit is the left most bit, no matter the
+ # `length` of `self`.
+ #
+ # ~~~
+ # assert "01".hexdigest_to_bytes.to_i(true) == 1
+ # assert "FF".hexdigest_to_bytes.to_i(true) == -1
+ # assert "00FF".hexdigest_to_bytes.to_i(true) == 255
+ # assert "E0".hexdigest_to_bytes.to_i(true) == -32
+ # assert "FE00".hexdigest_to_bytes.to_i(true) == -512
+ # assert "FEFEFE".hexdigest_to_bytes.to_i(true) == -65794
+ # ~~~
+ #
+ # `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"
+ #
+ # assert (-32).to_bytes.to_i(true) == -32
+ # ~~~
+ #
+ # Warning: `Int` might overflow for bytes with more than 60 bits.
+ fun to_i(signed: nullable Bool): Int do
+ var res = 0
+ var i = 0
+ while i < length do
+ res *= 256
+ res += self[i].to_i
+ i += 1
+ end
+
+ # Two's complement is `signed`
+ if signed == true and not_empty and first > 0x80u8 then
+ var ff = 0
+ for j in [0..length[ do
+ ff *= 0x100
+ ff += 0xFF
+ end
+
+ res = -((res ^ ff) + 1)
+ end
+
+ return res
end
# var b = new Bytes.with_capacity(1)
# Regenerates the buffer, necessary when it was persisted
private fun regen do
- var nns = new NativeString(capacity)
+ var nns = new CString(capacity)
items.copy_to(nns, length, 0, 0)
persisted = false
end
# Appends the `ln` first bytes of `ns` to self
- fun append_ns(ns: NativeString, ln: Int) do
+ fun append_ns(ns: CString, ln: Int) do
if persisted then regen
var nlen = length + ln
if nlen > capacity then enlarge(nlen)
end
# Appends `ln` bytes from `ns` starting at index `from` to self
- fun append_ns_from(ns: NativeString, ln, from: Int) do
+ fun append_ns_from(ns: CString, ln, from: Int) do
if persisted then regen
var nlen = length + ln
if nlen > capacity then enlarge(nlen)
length += ln
end
+ # Appends the bytes of `str` to `self`
+ fun append_text(str: Text) do str.append_to_bytes self
+
+ redef fun append_to(b) do b.append self
+
redef fun enlarge(sz) do
if capacity >= sz then return
persisted = false
+ if capacity < 16 then capacity = 16
while capacity < sz do capacity = capacity * 2 + 2
- var ns = new NativeString(capacity)
+ var ns = new CString(capacity)
items.copy_to(ns, length, 0, 0)
items = ns
end
redef fun to_s do
persisted = true
var b = self
- var r = b.items.to_s_with_length(length)
+ var r = b.items.to_s_unsafe(length, copy=false)
if r != items then persisted = false
return r
end
redef fun iterator do return new BytesIterator.with_buffer(self)
+ redef fun first_index_in_from(b, from) do
+ if is_empty then return -1
+ var fst = self[0]
+ var bpos = fst.first_index_in_from(self, from)
+ for i in [0 .. length[ do
+ if self[i] != b[bpos] then return first_index_in_from(b, bpos + 1)
+ bpos += 1
+ end
+ return bpos
+ end
+
+ redef fun last_index_in_from(b, from) do
+ if is_empty then return -1
+ var lst = self[length - 1]
+ var bpos = lst.last_index_in_from(b, from)
+ for i in [0 .. length[.step(-1) do
+ if self[i] != b[bpos] then return last_index_in_from(b, bpos - 1)
+ bpos -= 1
+ end
+ return bpos
+ end
+
+ redef fun search_all_in(b) do
+ var ret = new Array[Int]
+ var pos = first_index_in_from(b, 0)
+ if pos == -1 then return ret
+ pos = pos + 1
+ ret.add pos
+ loop
+ pos = first_index_in_from(b, pos)
+ if pos == -1 then return ret
+ ret.add pos
+ pos += length
+ end
+ end
+
+ # Splits the content on self when encountering `b`
+ #
+ # var a = "String is string".to_bytes.split_with('s'.ascii)
+ # assert a.length == 3
+ # assert a[0].hexdigest == "537472696E672069"
+ # assert a[1].hexdigest == "20"
+ # assert a[2].hexdigest == "7472696E67"
+ fun split_with(b: BytePattern): Array[Bytes] do
+ var fst = b.search_all_in(self)
+ if fst.is_empty then return [clone]
+ var retarr = new Array[Bytes]
+ var prev = 0
+ for i in fst do
+ retarr.add(slice(prev, i - prev))
+ prev = i + b.pattern_length
+ end
+ retarr.add slice_from(prev)
+ return retarr
+ end
+
+ # Splits `self` in two parts at the first occurence of `b`
+ #
+ # var a = "String is string".to_bytes.split_once_on('s'.ascii)
+ # assert a[0].hexdigest == "537472696E672069"
+ # assert a[1].hexdigest == "20737472696E67"
+ fun split_once_on(b: BytePattern): Array[Bytes] do
+ var spl = b.first_index_in(self)
+ if spl == -1 then return [clone]
+ var ret = new Array[Bytes].with_capacity(2)
+ ret.add(slice(0, spl))
+ ret.add(slice_from(spl + b.pattern_length))
+ return ret
+ end
+
+ # Replaces all the occurences of `this` in `self` by `by`
+ #
+ # var b = "String is string".to_bytes.replace(0x20u8, 0x41u8)
+ # assert b.hexdigest == "537472696E6741697341737472696E67"
+ fun replace(pattern: BytePattern, bytes: BytePattern): Bytes do
+ if is_empty then return new Bytes.empty
+ var pos = pattern.search_all_in(self)
+ if pos.is_empty then return clone
+ var ret = new Bytes.with_capacity(length)
+ var prev = 0
+ for i in pos do
+ ret.append_ns(items.fast_cstring(prev), i - prev)
+ bytes.append_to ret
+ prev = i + pattern.pattern_length
+ end
+ ret.append(slice_from(pos.last + pattern.pattern_length))
+ return ret
+ end
+
+ # Decode `self` from percent (or URL) encoding to a clear string
+ #
+ # Invalid '%' are not decoded.
+ #
+ # assert "aBc09-._~".to_bytes.from_percent_encoding == "aBc09-._~".to_bytes
+ # assert "%25%28%29%3c%20%3e".to_bytes.from_percent_encoding == "%()< >".to_bytes
+ # assert ".com%2fpost%3fe%3dasdf%26f%3d123".to_bytes.from_percent_encoding == ".com/post?e=asdf&f=123".to_bytes
+ # assert "%25%28%29%3C%20%3E".to_bytes.from_percent_encoding == "%()< >".to_bytes
+ # assert "incomplete %".to_bytes.from_percent_encoding == "incomplete %".to_bytes
+ # assert "invalid % usage".to_bytes.from_percent_encoding == "invalid % usage".to_bytes
+ # assert "%c3%a9%e3%81%82%e3%81%84%e3%81%86".to_bytes.from_percent_encoding == "éあいう".to_bytes
+ # assert "%1 %A %C3%A9A9".to_bytes.from_percent_encoding == "%1 %A éA9".to_bytes
+ fun from_percent_encoding: Bytes do
+ var tmp = new Bytes.with_capacity(length)
+ var pos = 0
+ while pos < length do
+ var b = self[pos]
+ if b != '%'.ascii then
+ tmp.add b
+ pos += 1
+ continue
+ end
+ if length - pos < 2 then
+ tmp.add '%'.ascii
+ pos += 1
+ continue
+ end
+ var bn = self[pos + 1]
+ var bnn = self[pos + 2]
+ if not bn.is_valid_hexdigit or not bnn.is_valid_hexdigit then
+ tmp.add '%'.ascii
+ pos += 1
+ continue
+ end
+ tmp.add((bn.hexdigit_to_byteval << 4) + bnn.hexdigit_to_byteval)
+ pos += 3
+ end
+ return tmp
+ end
+
+ # Is `b` a prefix of `self` ?
+ fun has_prefix(b: BytePattern): Bool do return b.is_prefix(self)
+
+ # Is `b` a suffix of `self` ?
+ fun has_suffix(b: BytePattern): Bool do return b.is_suffix(self)
+
+ redef fun is_suffix(b) do
+ if length > b.length then return false
+ var j = b.length - 1
+ var i = length - 1
+ while i > 0 do
+ if self[i] != b[j] then return false
+ i -= 1
+ j -= 1
+ end
+ return true
+ end
+
+ redef fun is_prefix(b) do
+ if length > b.length then return false
+ for i in [0 .. length[ do if self[i] != b[i] then return false
+ return true
+ end
end
private class BytesIterator
super IndexedIterator[Byte]
- var tgt: NativeString
+ var tgt: CString
redef var index
redef fun item do return tgt[index]
end
+redef class Int
+ # A signed 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"
+ # ~~~
+ #
+ # Negative values are converted to their two's complement.
+ # Be careful as the result can be ambiguous.
+ #
+ # ~~~
+ # assert (-1).to_bytes.hexdigest == "FF"
+ # assert (-32).to_bytes.hexdigest == "E0"
+ # assert (-512).to_bytes.hexdigest == "FE00"
+ # assert (-65794).to_bytes.hexdigest == "FEFEFE"
+ # ~~~
+ #
+ # Optionally, set `n_bytes` to the desired number of bytes in the output.
+ # This setting can disambiguate the result between positive and negative
+ # integers. Be careful with this parameter as the result may overflow.
+ #
+ # ~~~
+ # assert 1.to_bytes(2).hexdigest == "0001"
+ # assert 65535.to_bytes(2).hexdigest == "FFFF"
+ # assert (-1).to_bytes(2).hexdigest == "FFFF"
+ # assert (-512).to_bytes(4).hexdigest == "FFFFFE00"
+ # assert 0x123456.to_bytes(2).hexdigest == "3456"
+ # ~~~
+ #
+ # For 0, a Bytes object with single nul byte is returned (instead of an empty Bytes object).
+ #
+ # ~~~
+ # assert 0.to_bytes.hexdigest == "00"
+ # ~~~
+ #
+ # For positive integers, `Bytes::to_i` can reverse the operation.
+ #
+ # ~~~
+ # assert 1234.to_bytes.to_i == 1234
+ # ~~~
+ #
+ # Require self >= 0
+ fun to_bytes(n_bytes: nullable Int): Bytes do
+
+ # If 0, force using at least one byte
+ if self == 0 and n_bytes == null then n_bytes = 1
+
+ # Compute the len (log256)
+ var len = 1
+ var max = 256
+ var s = self.abs
+ while s >= max do
+ len += 1
+ max *= 256
+ end
+
+ # Two's complement
+ s = self
+ if self < 0 then
+ var ff = 0
+ for j in [0..len[ do
+ ff *= 0x100
+ ff += 0xFF
+ end
+
+ s = ((-self) ^ ff) + 1
+ end
+
+ # Cut long values
+ if n_bytes != null and len > n_bytes then len = n_bytes
+
+ # Allocate the buffer
+ var cap = n_bytes or else len
+ var res = new Bytes.with_capacity(cap)
+
+ var filler = if self < 0 then 0xFFu8 else 0u8
+ for i in [0..cap[ do res[i] = filler
+
+ # Fill it starting with the end
+ var i = cap
+ var sum = s
+ while i > cap - len 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"
+ #
+ # 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"
#
- # REQUIRE: `self` is a valid hexdigest and hexdigest.length % 2 == 0
+ # 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 outns = new NativeString(ln * 2)
+ var ln = byte_length
+ var outns = new CString(ln * 2)
var oi = 0
for i in [0 .. ln[ do
bytes[i].add_digest_at(outns, oi)
oi += 2
end
- return new FlatString.with_infos(outns, ln * 2, 0, ln * 2 - 1)
+ return new FlatString.with_infos(outns, ln * 2, 0)
+ end
+
+ # 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.byte_length)
+ var was_slash = false
+ var i = 0
+ while i < length do
+ var c = self[i]
+ if not was_slash then
+ if c == '\\' then
+ was_slash = true
+ else
+ res.add_char(c)
+ end
+ i += 1
+ continue
+ end
+ was_slash = false
+ if c == 'n' then
+ res.add_char('\n')
+ else if c == 'r' then
+ res.add_char('\r')
+ else if c == 't' then
+ res.add_char('\t')
+ else if c == '0' then
+ res.add_char('\0')
+ else if c == 'x' or c == 'X' then
+ var hx = substring(i + 1, 2)
+ if hx.is_hex then
+ res.add(hx.to_hex.to_b)
+ else
+ res.add_char(c)
+ end
+ i += 2
+ else if c == 'u' or c == 'U' then
+ var hx = substring(i + 1, 6)
+ if hx.is_hex then
+ res.add_char(hx.to_hex.code_point)
+ else
+ res.add_char(c)
+ end
+ i += 6
+ else
+ res.add_char(c)
+ end
+ i += 1
+ 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)
+ if isset _items then b.append_ns_from(items, byte_length, from)
end
end
-redef class NativeString
- # Creates a new `Bytes` object from `self` with `strlen` as length
- fun to_bytes: Bytes do
- var len = cstring_length
+redef class CString
+ # Creates a new `Bytes` object from `self` with `len` as length
+ #
+ # If `len` is null, strlen will determine the length of the Bytes
+ fun to_bytes(len: nullable Int): Bytes do
+ if len == null then len = cstring_length
return new Bytes(self, len, len)
end
+
+ # Creates a new `Bytes` object from a copy of `self` with `len` as length
+ #
+ # If `len` is null, strlen will determine the length of the Bytes
+ fun to_bytes_with_copy(len: nullable Int): Bytes do
+ if len == null then len = cstring_length
+ var nns = new CString(len)
+ copy_to(nns, len, 0, 0)
+ return new Bytes(nns, len, len)
+ end
+end
+
+# Joins an array of bytes `arr` separated by `sep`
+#
+# assert join_bytes(["String".to_bytes, "is".to_bytes, "string".to_bytes], ' '.ascii).hexdigest == "537472696E6720697320737472696E67"
+fun join_bytes(arr: Array[Bytes], sep: nullable BytePattern): Bytes do
+ if arr.is_empty then return new Bytes.empty
+ sep = sep or else new Bytes.empty
+ var endln = sep.pattern_length * (arr.length - 1)
+ for i in arr do endln += i.length
+ var ret = new Bytes.with_capacity(endln)
+ ret.append(arr.first)
+ for i in [1 .. arr.length[ do
+ sep.append_to(ret)
+ ret.append arr[i]
+ end
+ return ret
end