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util/hex.lua @ 6705:c269ab6ab98a
Merge 0.10->trunk
author | Kim Alvefur <zash@zash.se> |
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date | Fri, 15 May 2015 15:33:31 +0200 |
parent | 6545:ec566d7cd518 |
child | 6802:442019e955dc |
rev | line source |
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6375
76d8907d5301
util.hex: Small util lib for converting to/from hex strings
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
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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
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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
diff
changeset
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3 local s_gsub = string.gsub; |
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
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4 |
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
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5 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
|
6 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
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7 |
6545
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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
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8 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
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9 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
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10 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
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11 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
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12 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
|
13 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
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14 end |
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util.hex: Small util lib for converting to/from hex strings
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
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15 end |
76d8907d5301
util.hex: Small util lib for converting to/from hex strings
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
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16 |
6384 | 17 local function to(s) |
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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
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18 return (s_gsub(s, ".", char_to_hex)); |
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util.hex: Small util lib for converting to/from hex strings
Matthew Wild <mwild1@gmail.com>
parents:
diff
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19 end |
76d8907d5301
util.hex: Small util lib for converting to/from hex strings
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
20 |
6384 | 21 local function from(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
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22 return (s_gsub(s, "..", 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:
diff
changeset
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23 end |
76d8907d5301
util.hex: Small util lib for converting to/from hex strings
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
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24 |
76d8907d5301
util.hex: Small util lib for converting to/from hex strings
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
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25 return { to = to, from = from } |