prosody
22066b02887f
util/hex.lua

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util/hex.lua @ 12781:22066b02887f

util.startup: Provide a common Lua 5.3+ math.type() for Lua 5.2 Code deduplication
author Kim Alvefur <zash@zash.se>
date Wed, 19 Oct 2022 16:25:05 +0200
parent 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:
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1 local s_char = string.char;
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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
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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
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3 local s_gsub = string.gsub;
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442019e955dc util.hex: Normalize hex to lowercase and discard non-hex input
Kim Alvefur <zash@zash.se>
parents: 6545
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4 local s_lower = string.lower;
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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
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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
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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
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7 local hex_to_char = {};
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76d8907d5301 util.hex: Small util lib for converting to/from hex strings
Matthew Wild <mwild1@gmail.com>
parents:
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8
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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
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9 do
ec566d7cd518 util.hex: Pedantic optimization, 1 table lookup per byte instead of 3 function calls makes it go faster
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parents: 6384
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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
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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
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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
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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
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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
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15 end
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76d8907d5301 util.hex: Small util lib for converting to/from hex strings
Matthew Wild <mwild1@gmail.com>
parents:
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16 end
76d8907d5301 util.hex: Small util lib for converting to/from hex strings
Matthew Wild <mwild1@gmail.com>
parents:
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17
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3f4809d01783 util.hex: Use locals!
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parents: 6375
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18 local function to(s)
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parents: 6384
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19 return (s_gsub(s, ".", char_to_hex));
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76d8907d5301 util.hex: Small util lib for converting to/from hex strings
Matthew Wild <mwild1@gmail.com>
parents:
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20 end
76d8907d5301 util.hex: Small util lib for converting to/from hex strings
Matthew Wild <mwild1@gmail.com>
parents:
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21
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3f4809d01783 util.hex: Use locals!
Kim Alvefur <zash@zash.se>
parents: 6375
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22 local function from(s)
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23 return (s_gsub(s_lower(s), "%X*(%x%x)%X*", hex_to_char));
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Matthew Wild <mwild1@gmail.com>
parents:
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24 end
76d8907d5301 util.hex: Small util lib for converting to/from hex strings
Matthew Wild <mwild1@gmail.com>
parents:
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25
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Matthew Wild <mwild1@gmail.com>
parents: 6802
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26 return {
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parents: 6802
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27 encode = to, decode = from;
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Matthew Wild <mwild1@gmail.com>
parents: 6802
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28 -- COMPAT w/pre-0.12:
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Matthew Wild <mwild1@gmail.com>
parents: 6802
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29 to = to, from = from;
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Matthew Wild <mwild1@gmail.com>
parents: 6802
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30 };