Data update
This commit is contained in:
Ingy döt Net
parent
4bb20c9b71
commit
cbaf4c4b64
12390 changed files with 318560 additions and 27248 deletions
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@ -0,0 +1,92 @@
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with Ada.Containers.Vectors;
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with Ada.Text_IO;
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with Ada.Unchecked_Conversion;
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procedure VLQ is
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package Nat_IO is new Ada.Text_IO.Integer_IO (Natural);
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type Byte is mod 2**8;
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package Byte_IO is new Ada.Text_IO.Modular_IO (Byte);
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type Int7 is mod 2**7;
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package Int7_IO is new Ada.Text_IO.Modular_IO (Int7);
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type VLQ_Octet is record
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Value : Int7 := 0;
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Next : Boolean := True;
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end record;
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pragma Pack (VLQ_Octet);
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for VLQ_Octet'Size use 8;
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function VLQ_To_Byte is new Ada.Unchecked_Conversion (VLQ_Octet, Byte);
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function Byte_To_VLQ is new Ada.Unchecked_Conversion (Byte, VLQ_Octet);
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package VLQ_Vectors is new Ada.Containers.Vectors (Natural, VLQ_Octet);
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procedure Hex_Print (Position : in VLQ_Vectors.Cursor) is
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Value : Byte := VLQ_To_Byte (VLQ_Vectors.Element (Position));
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begin
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Ada.Text_IO.Put (':');
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Byte_IO.Put (Item => Value, Width => 6, Base => 16);
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end Hex_Print;
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procedure Print (X : VLQ_Vectors.Vector) is
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begin
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X.Iterate (Hex_Print'Access);
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Ada.Text_IO.New_Line;
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end Print;
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function To_VLQ (From : Natural) return VLQ_Vectors.Vector is
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Result : VLQ_Vectors.Vector;
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Current : Natural := From;
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Element : VLQ_Octet;
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begin
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loop
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Element.Value := Int7 (Current mod 2**7);
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Result.Prepend (Element);
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Current := Current / 2**7;
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exit when Current = 0;
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end loop;
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Element := Result.Last_Element;
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Element.Next := False;
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VLQ_Vectors.Replace_Element (Result, Result.Last, Element);
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return Result;
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end To_VLQ;
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function To_Int (From : VLQ_Vectors.Vector) return Natural is
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use type VLQ_Vectors.Cursor;
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Result : Natural := 0;
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Iterator : VLQ_Vectors.Cursor := From.First;
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begin
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while Iterator /= VLQ_Vectors.No_Element loop
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Result := Result * 2**7;
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Result := Result + Natural(VLQ_Vectors.Element (Iterator).Value);
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VLQ_Vectors.Next (Iterator);
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end loop;
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return Result;
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end To_Int;
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Test : VLQ_Vectors.Vector;
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begin
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Test := To_VLQ (16#7f#);
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Nat_IO.Put (To_Int (Test), 10, 16); Ada.Text_IO.Put (" = ");
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Print (Test);
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Test := To_VLQ (16#4000#);
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Nat_IO.Put (To_Int (Test), 10, 16); Ada.Text_IO.Put (" = ");
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Print (Test);
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Test := To_VLQ (16#0#);
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Nat_IO.Put (To_Int (Test), 10, 16); Ada.Text_IO.Put (" = ");
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Print (Test);
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Test := To_VLQ (16#3FFFFE#);
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Nat_IO.Put (To_Int (Test), 10, 16); Ada.Text_IO.Put (" = ");
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Print (Test);
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Test := To_VLQ (16#1FFFFF#);
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Nat_IO.Put (To_Int (Test), 10, 16); Ada.Text_IO.Put (" = ");
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Print (Test);
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Test := To_VLQ (16#200000#);
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Nat_IO.Put (To_Int (Test), 10, 16); Ada.Text_IO.Put (" = ");
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Print (Test);
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end VLQ;
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@ -0,0 +1,23 @@
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def vl_encode (n)
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raise "negative numbers aren't vl-encodeable" unless n >= 0
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bytes_needed = n == 0 ? 1 : (n.bit_length - 1) // 7 + 1
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bytes = Bytes.new(bytes_needed)
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(0...bytes_needed).reverse_each do |i|
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bytes[i] = (n & 127).to_u8 | 128
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n >>= 7
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end
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bytes[-1] &= 127
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bytes
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end
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def vl_decode (bytes)
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size = (bytes.size - 1) * 7 + (bytes[0] & 127).bit_length
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n = size > 63 ? 0.to_i128 : size > 31 ? 0.to_i64 : 0
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bytes.reduce(n) {|result, byte| (result << 7) + (byte & 127) }
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end
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[0x200000, 0x1fffff].each do |n|
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encoded = vl_encode(n)
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decoded = vl_decode(encoded)
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puts "%8d %12s %8d" % { n, encoded.map {|b| "%02x" % b }.join(":"), decoded }
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end
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@ -21,8 +21,8 @@ struct VLQ {
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"Too large for ulong or invalid format.");
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else
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value = (t << 7) | v[idx];
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return idx + 1;
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}
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return cast(uint) idx + 1;
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}
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VLQ from(in ubyte[] v) pure {
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extract(v);
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@ -54,7 +54,6 @@ struct VLQ {
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}
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}
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void main() { // VLQ demo code.
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VLQ a = VLQ(0x7f),
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b = VLQ(0x4000),
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@ -0,0 +1,41 @@
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function vlq_encode(integer n)
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sequence s
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s = {}
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while n > 0 do
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s = prepend(s, #80 * (length(s) > 0) + and_bits(n, #7F))
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n = floor(n / #80)
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end while
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if length(s) = 0 then
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s = {0}
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end if
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return s
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end function
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function vlq_decode(sequence s)
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integer n
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n = 0
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for i = 1 to length(s) do
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n *= #80
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n += and_bits(s[i], #7F)
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if not and_bits(s[i], #80) then
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exit
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end if
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end for
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return n
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end function
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function svlg(sequence s)
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sequence out
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out = ""
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for i = 1 to length(s) do
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out &= sprintf("#%02x:", {s[i]})
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end for
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return out[1..$-1]
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end function
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constant testNumbers = { #200000, #1FFFFF, 1, 127, 128 }
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sequence s
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for i = 1 to length(testNumbers) do
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s = vlq_encode(testNumbers[i])
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printf(1, "#%02x -> %s -> #%02x\n", {testNumbers[i], svlg(s), vlq_decode(s)})
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end for
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@ -0,0 +1,17 @@
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let to_vlq n =
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let a, b = n >>> 7, n &&& 0x7F
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let rec aux n acc =
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let x,xs = (n &&& 0x7F) ||| 0x80, n >>> 7
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if xs > 0 then aux xs (x::acc) else x::acc
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aux a [b]
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let to_num = List.fold (fun n x -> (n <<< 7) + (x &&& 0x7F)) 0
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let v_rep n =
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let seq = to_vlq n
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printf "%d ->" n
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List.iter (printf " 0x%02X") seq
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printfn " -> %d" (to_num seq)
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v_rep 0x200000
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v_rep 0x1FFFFF
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@ -1,33 +1,35 @@
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using Printf
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mutable struct VLQ
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quant::Vector{UInt8}
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quant::Vector{UInt8}
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end
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function VLQ(n::T) where T <: Integer
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quant = UInt8.(digits(n, 128))
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@inbounds for i in 2:length(quant) quant[i] |= 0x80 end
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VLQ(reverse(quant))
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quant = UInt8.(digits(n, base = 128))
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@inbounds for i in 2:lastindex(quant)
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quant[i] |= 0x80
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end
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VLQ(reverse(quant))
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end
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import Base.UInt64
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function Base.UInt64(vlq::VLQ)
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quant = reverse(vlq.quant)
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n = shift!(quant)
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p = one(UInt64)
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for i in quant
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p *= 0x80
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n += p * ( i & 0x7f)
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end
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return n
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quant = reverse(vlq.quant)
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n = popfirst!(quant)
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p = one(UInt64)
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for i in quant
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p *= 0x80
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n += p * (i & 0x7f)
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end
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return n
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end
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const test = [0x00200000, 0x001fffff, 0x00000000, 0x0000007f,
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0x00000080, 0x00002000, 0x00003fff, 0x00004000,
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0x08000000, 0x0fffffff]
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0x00000080, 0x00002000, 0x00003fff, 0x00004000,
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0x08000000, 0x0fffffff]
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for i in test
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vlq = VLQ(i)
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j = UInt(vlq)
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@printf "0x%-8x => [%-25s] => 0x%x\n" i join(("0x" * hex(r, 2) for r in vlq.quant), ", ") j
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vlq = VLQ(i)
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j = UInt(vlq)
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@printf "0x%-8x => [%-25s] => 0x%x\n" i join(("0x" * string(r, base = 16, pad = 2) for r in vlq.quant), ", ") j
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end
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@ -1,43 +1,38 @@
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-->
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<span style="color: #008080;">function</span> <span style="color: #000000;">vlq_encode</span><span style="color: #0000FF;">(</span><span style="color: #004080;">sequence</span> <span style="color: #000000;">s</span><span style="color: #0000FF;">)</span>
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<span style="color: #004080;">sequence</span> <span style="color: #000000;">res</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{}</span>
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<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">s</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">to</span> <span style="color: #000000;">1</span> <span style="color: #008080;">by</span> <span style="color: #0000FF;">-</span><span style="color: #000000;">1</span> <span style="color: #008080;">do</span>
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<span style="color: #004080;">integer</span> <span style="color: #000000;">n</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">s</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">],</span> <span style="color: #000000;">msb</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span>
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<span style="color: #008080;">if</span> <span style="color: #000000;">n</span><span style="color: #0000FF;"><</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span> <span style="color: #7060A8;">crash</span><span style="color: #0000FF;">(</span><span style="color: #008000;">"unsigned integers only!"</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
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<span style="color: #008080;">while</span> <span style="color: #000000;">1</span> <span style="color: #008080;">do</span>
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<span style="color: #000000;">res</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">prepend</span><span style="color: #0000FF;">(</span><span style="color: #000000;">res</span><span style="color: #0000FF;">,</span><span style="color: #000000;">msb</span><span style="color: #0000FF;">+</span><span style="color: #7060A8;">and_bits</span><span style="color: #0000FF;">(</span><span style="color: #000000;">n</span><span style="color: #0000FF;">,</span><span style="color: #000000;">#7F</span><span style="color: #0000FF;">))</span>
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<span style="color: #000000;">n</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">floor</span><span style="color: #0000FF;">(</span><span style="color: #000000;">n</span><span style="color: #0000FF;">/</span><span style="color: #000000;">#80</span><span style="color: #0000FF;">)</span>
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<span style="color: #008080;">if</span> <span style="color: #000000;">n</span><span style="color: #0000FF;">=</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span> <span style="color: #008080;">exit</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
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<span style="color: #000000;">msb</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">#80</span>
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<span style="color: #008080;">end</span> <span style="color: #008080;">while</span>
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<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
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<span style="color: #008080;">return</span> <span style="color: #000000;">res</span>
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<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
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with javascript_semantics
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<span style="color: #008080;">function</span> <span style="color: #000000;">vlq_decode</span><span style="color: #0000FF;">(</span><span style="color: #004080;">sequence</span> <span style="color: #000000;">s</span><span style="color: #0000FF;">)</span>
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<span style="color: #004080;">sequence</span> <span style="color: #000000;">res</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{}</span>
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<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">s</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span>
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<span style="color: #004080;">integer</span> <span style="color: #000000;">si</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">s</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">],</span>
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<span style="color: #000000;">n</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">n</span><span style="color: #0000FF;">*</span><span style="color: #000000;">#80</span><span style="color: #0000FF;">+</span><span style="color: #7060A8;">and_bits</span><span style="color: #0000FF;">(</span><span style="color: #004080;">byte</span><span style="color: #0000FF;">,</span><span style="color: #000000;">#7F</span><span style="color: #0000FF;">)</span>
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<span style="color: #008080;">if</span> <span style="color: #008080;">not</span> <span style="color: #7060A8;">and_bits</span><span style="color: #0000FF;">(</span><span style="color: #000000;">si</span><span style="color: #0000FF;">,</span><span style="color: #000000;">#80</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">then</span>
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<span style="color: #000000;">res</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">append</span><span style="color: #0000FF;">(</span><span style="color: #000000;">res</span><span style="color: #0000FF;">,</span><span style="color: #000000;">n</span><span style="color: #0000FF;">)</span>
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<span style="color: #000000;">n</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span>
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<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
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<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
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<span style="color: #008080;">return</span> <span style="color: #000000;">res</span>
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<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
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function vlq_encode(sequence s)
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sequence res = {}
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for i=length(s) to 1 by -1 do
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integer n = s[i], msb = 0
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if n<0 then crash("unsigned integers only!") end if
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while 1 do
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res = prepend(res,msb+and_bits(n,#7F))
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n = floor(n/#80)
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if n=0 then exit end if
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msb = #80
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end while
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end for
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return res
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end function
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<span style="color: #008080;">function</span> <span style="color: #000000;">svlg</span><span style="color: #0000FF;">(</span><span style="color: #004080;">sequence</span> <span style="color: #000000;">s</span><span style="color: #0000FF;">)</span>
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<span style="color: #004080;">string</span> <span style="color: #000000;">res</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">""</span>
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<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">s</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span>
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<span style="color: #000000;">res</span> <span style="color: #0000FF;">&=</span> <span style="color: #7060A8;">sprintf</span><span style="color: #0000FF;">(</span><span style="color: #008000;">"#%02x:"</span><span style="color: #0000FF;">,{</span><span style="color: #000000;">s</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]})</span>
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<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
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<span style="color: #008080;">return</span> <span style="color: #000000;">res</span><span style="color: #0000FF;">[</span><span style="color: #000000;">1</span><span style="color: #0000FF;">..$-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]</span>
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<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
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function vlq_decode(sequence s)
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sequence res = {}
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integer n = 0
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for si in s do
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n = n*#80+and_bits(si,#7F)
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if not and_bits(si,#80) then
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res = append(res,n)
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n = 0
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end if
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end for
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return res
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end function
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<span style="color: #008080;">constant</span> <span style="color: #000000;">testNumbers</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{</span> <span style="color: #000000;">#200000</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">#1FFFFF</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">1</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">127</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">128</span> <span style="color: #0000FF;">}</span>
|
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<span style="color: #004080;">sequence</span> <span style="color: #000000;">s</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">vlq_encode</span><span style="color: #0000FF;">(</span><span style="color: #000000;">testNumbers</span><span style="color: #0000FF;">),</span>
|
||||
<span style="color: #000000;">decoded</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">vlq_decode</span><span style="color: #0000FF;">(</span><span style="color: #000000;">s</span><span style="color: #0000FF;">)</span>
|
||||
<span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"%s -> %s -> %s\n"</span><span style="color: #0000FF;">,{</span><span style="color: #000000;">svlg</span><span style="color: #0000FF;">(</span><span style="color: #000000;">testNumbers</span><span style="color: #0000FF;">),</span><span style="color: #000000;">svlg</span><span style="color: #0000FF;">(</span><span style="color: #000000;">s</span><span style="color: #0000FF;">),</span><span style="color: #000000;">svlg</span><span style="color: #0000FF;">(</span><span style="color: #000000;">decoded</span><span style="color: #0000FF;">)})</span>
|
||||
<span style="color: #008080;">if</span> <span style="color: #000000;">decoded</span><span style="color: #0000FF;">!=</span><span style="color: #000000;">testNumbers</span> <span style="color: #008080;">then</span> <span style="color: #7060A8;">crash</span><span style="color: #0000FF;">(</span><span style="color: #008000;">"something wrong"</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
|
||||
<!--
|
||||
function svlg(sequence s)
|
||||
return join(s,':',fmt:="#%02x")
|
||||
end function
|
||||
|
||||
constant testNumbers = { #200000, #1FFFFF, #00, #01, #7F, #80 }
|
||||
sequence s = vlq_encode(testNumbers), decoded = vlq_decode(s)
|
||||
printf(1,"%s -> %s -> %s\n",{svlg(testNumbers),svlg(s),svlg(decoded)})
|
||||
if decoded!=testNumbers then crash("something wrong") end if
|
||||
|
|
|
|||
|
|
@ -0,0 +1,34 @@
|
|||
local fmt = require "fmt"
|
||||
|
||||
local function to_octets(n)
|
||||
local s = fmt.bin(n)
|
||||
local le = #s
|
||||
local r = le % 7
|
||||
local d = le // 7
|
||||
if r > 0 then
|
||||
d += 1
|
||||
s = fmt.lpad(s, 7 * d, "0")
|
||||
end
|
||||
local chunks = s:split(""):chunk(7):map(|ch| -> ch:concat(""))
|
||||
local last = "0" .. chunks:back()
|
||||
s = chunks:slice(1, -2):map(|ch| -> "1" .. ch):concat("") .. last
|
||||
return s:split(""):chunk(8):map(|ch| -> tonumber(ch:concat(""), 2))
|
||||
end
|
||||
|
||||
local function from_octets(octets)
|
||||
local s = ""
|
||||
for octets as oct do
|
||||
local bin = fmt.bin(oct)
|
||||
bin = fmt.lpad(bin, 7, "0")
|
||||
s ..= bin:sub(-7)
|
||||
end
|
||||
return tonumber(s, 2)
|
||||
end
|
||||
|
||||
local tests = {2097152, 2097151}
|
||||
for tests as test do
|
||||
local octets = to_octets(test)
|
||||
local display = octets:mapped(|oct| -> "Ox" .. string.format("%02x", oct))
|
||||
io.write($"{test} -> {fmt.swrite(display, " ", "")} -> ")
|
||||
print(from_octets(octets))
|
||||
end
|
||||
|
|
@ -0,0 +1,33 @@
|
|||
fn vlq_encode_4bytes(n u32) []u8 {
|
||||
mut bytes := []u8{len: 4}
|
||||
bytes[0] = u8((n & 0x7f) | 0x80)
|
||||
bytes[1] = u8(((n >> 7) & 0x7f) | 0x80)
|
||||
bytes[2] = u8(((n >> 14) & 0x7f) | 0x80)
|
||||
bytes[3] = u8((n >> 21) & 0x7f) // cleared on last byte
|
||||
return bytes
|
||||
}
|
||||
|
||||
fn vlq_decode_4bytes(bytes []u8) u32 {
|
||||
mut n := u32(0)
|
||||
n |= u32(bytes[0] & 0x7f) << 0
|
||||
n |= u32(bytes[1] & 0x7f) << 7
|
||||
n |= u32(bytes[2] & 0x7f) << 14
|
||||
n |= u32(bytes[3] & 0x7f) << 21
|
||||
return n
|
||||
}
|
||||
|
||||
fn byte_to_hex(b u8) string {
|
||||
hex := b.hex()
|
||||
return if hex.len == 1 { '0' + hex } else { hex }
|
||||
}
|
||||
|
||||
fn main() {
|
||||
values := [u32(0x200000), u32(0x1fffff)]
|
||||
for x in values {
|
||||
encoded := vlq_encode_4bytes(x)
|
||||
hex_str := encoded.map(byte_to_hex).join('')
|
||||
println('$x encodes into ${encoded.len} bytes: $hex_str')
|
||||
decoded := vlq_decode_4bytes(encoded)
|
||||
println('$decoded decoded')
|
||||
}
|
||||
}
|
||||
Loading…
Add table
Add a link
Reference in a new issue