Annotate

util/hex.lua @ 8341:910d3c3f60a6

mod_pep_plus: Use feature detection from pubsub.lib
author Kim Alvefur <zash@zash.se>
date Wed, 18 Oct 2017 09:43:43 +0200
parent 6802:442019e955dc
child 12355:a0ff5c438e9d
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
6375
76d8907d5301 util.hex: Small util lib for converting to/from hex strings
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
1 local s_char = string.char;
6545
ec566d7cd518 util.hex: Pedantic optimization, 1 table lookup per byte instead of 3 function calls makes it go faster
Kim Alvefur <zash@zash.se>
parents: 6384
diff changeset
2 local s_format = string.format;
ec566d7cd518 util.hex: Pedantic optimization, 1 table lookup per byte instead of 3 function calls makes it go faster
Kim Alvefur <zash@zash.se>
parents: 6384
diff changeset
3 local s_gsub = string.gsub;
6802
442019e955dc util.hex: Normalize hex to lowercase and discard non-hex input
Kim Alvefur <zash@zash.se>
parents: 6545
diff changeset
4 local s_lower = string.lower;
6545
ec566d7cd518 util.hex: Pedantic optimization, 1 table lookup per byte instead of 3 function calls makes it go faster
Kim Alvefur <zash@zash.se>
parents: 6384
diff changeset
5
ec566d7cd518 util.hex: Pedantic optimization, 1 table lookup per byte instead of 3 function calls makes it go faster
Kim Alvefur <zash@zash.se>
parents: 6384
diff changeset
6 local char_to_hex = {};
ec566d7cd518 util.hex: Pedantic optimization, 1 table lookup per byte instead of 3 function calls makes it go faster
Kim Alvefur <zash@zash.se>
parents: 6384
diff changeset
7 local hex_to_char = {};
6375
76d8907d5301 util.hex: Small util lib for converting to/from hex strings
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
8
6545
ec566d7cd518 util.hex: Pedantic optimization, 1 table lookup per byte instead of 3 function calls makes it go faster
Kim Alvefur <zash@zash.se>
parents: 6384
diff changeset
9 do
ec566d7cd518 util.hex: Pedantic optimization, 1 table lookup per byte instead of 3 function calls makes it go faster
Kim Alvefur <zash@zash.se>
parents: 6384
diff changeset
10 local char, hex;
ec566d7cd518 util.hex: Pedantic optimization, 1 table lookup per byte instead of 3 function calls makes it go faster
Kim Alvefur <zash@zash.se>
parents: 6384
diff changeset
11 for i = 0,255 do
ec566d7cd518 util.hex: Pedantic optimization, 1 table lookup per byte instead of 3 function calls makes it go faster
Kim Alvefur <zash@zash.se>
parents: 6384
diff changeset
12 char, hex = s_char(i), s_format("%02x", i);
ec566d7cd518 util.hex: Pedantic optimization, 1 table lookup per byte instead of 3 function calls makes it go faster
Kim Alvefur <zash@zash.se>
parents: 6384
diff changeset
13 char_to_hex[char] = hex;
ec566d7cd518 util.hex: Pedantic optimization, 1 table lookup per byte instead of 3 function calls makes it go faster
Kim Alvefur <zash@zash.se>
parents: 6384
diff changeset
14 hex_to_char[hex] = char;
ec566d7cd518 util.hex: Pedantic optimization, 1 table lookup per byte instead of 3 function calls makes it go faster
Kim Alvefur <zash@zash.se>
parents: 6384
diff changeset
15 end
6375
76d8907d5301 util.hex: Small util lib for converting to/from hex strings
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
16 end
76d8907d5301 util.hex: Small util lib for converting to/from hex strings
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
17
6384
3f4809d01783 util.hex: Use locals!
Kim Alvefur <zash@zash.se>
parents: 6375
diff changeset
18 local function to(s)
6545
ec566d7cd518 util.hex: Pedantic optimization, 1 table lookup per byte instead of 3 function calls makes it go faster
Kim Alvefur <zash@zash.se>
parents: 6384
diff changeset
19 return (s_gsub(s, ".", char_to_hex));
6375
76d8907d5301 util.hex: Small util lib for converting to/from hex strings
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
20 end
76d8907d5301 util.hex: Small util lib for converting to/from hex strings
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
21
6384
3f4809d01783 util.hex: Use locals!
Kim Alvefur <zash@zash.se>
parents: 6375
diff changeset
22 local function from(s)
6802
442019e955dc util.hex: Normalize hex to lowercase and discard non-hex input
Kim Alvefur <zash@zash.se>
parents: 6545
diff changeset
23 return (s_gsub(s_lower(s), "%X*(%x%x)%X*", hex_to_char));
6375
76d8907d5301 util.hex: Small util lib for converting to/from hex strings
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
24 end
76d8907d5301 util.hex: Small util lib for converting to/from hex strings
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
25
76d8907d5301 util.hex: Small util lib for converting to/from hex strings
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
26 return { to = to, from = from }