diff options
| -rw-r--r-- | plugins/bencode.lua | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/plugins/bencode.lua b/plugins/bencode.lua new file mode 100644 index 0000000..8a704fd --- /dev/null +++ b/plugins/bencode.lua @@ -0,0 +1,80 @@ +-- +-- bencode.lua: BitTorrent data encoding +-- +-- Copyright (c) 2017, Přemysl Janouch <p.janouch@gmail.com> +-- +-- Permission to use, copy, modify, and/or distribute this software for any +-- purpose with or without fee is hereby granted, provided that the above +-- copyright notice and this permission notice appear in all copies. +-- +-- THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES +-- WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF +-- MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY +-- SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES +-- WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION +-- OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN +-- CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. +-- + +local detect = function (c) + -- There is no magic to go by + return false +end + +-- We're not making it exactly readable but at least we're trying +local function one_value (c, level) + local p, type = c.position, c:read (1) + if type == "e" then + c (p, c.position -1):mark ("%d: container end", level - 1) + return false + elseif type == "i" then + local n = "" + type = c:read (1) + while type ~= "e" do + n = n .. type + type = c:read (1) + end + c (p, c.position - 1):mark ("%d: integer: %s", level, n) + elseif type == "l" then + c (p, p):mark ("%d: list begin", level) + local i = 0 + while true do + local p = c.position + if not one_value (c, level + 1) then break end + c (p, c.position - 1):mark ("%d: list value %d", level, i) + i = i + 1 + end + elseif type == "d" then + c (p, p):mark ("%d: dictionary begin", level) + while true do + local p = c.position + if not one_value (c, level + 1) then break end + c (p, c.position - 1):mark ("%d: dictionary key", level) + + local p = c.position + if not one_value (c, level + 1) then break end + c (p, c.position - 1):mark ("%d: dictionary value", level) + end + else + local n = type + type = c:read (1) + while type ~= ":" do + n = n .. type + type = c:read (1) + end + c (p, c.position - 1):mark ("%d: string length: %s", level, n) + + p = c.position + c:read (tonumber (n)) + c (p, c.position - 1):mark ("%d: string value", level) + end + return true +end + +local decode = function (c) + while not c.eof do + one_value (c, 0) + end +end + +hex.register { type="bencode", detect=detect, decode=decode } |