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util/bitcompat.lua @ 10973:39991e40d1dc
util.dbuffer: dynamic string buffer
Similar to util.ringbuffer (and shares almost identical API). Differences:
- size limit is optional and dynamic
- does not allocate a fixed buffer of max_size bytes
- focus on simply storing references to existing string objects where possible,
avoiding unnecessary allocations
- references are still stored in a ring buffer to enable use as a fast FIFO
Optional second parameter to new() provides the number of ring buffer segments. On
Lua 5.2 on my laptop, a segment is ~19 bytes. If the ring buffer fills up, the next
write will compact all strings into a single item.
author | Matthew Wild <mwild1@gmail.com> |
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date | Fri, 26 Jun 2020 16:41:31 +0100 |
parent | 10241:48f7cda4174d |
child | 12573:0f4feaf9ca64 |
rev | line source |
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10241
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util.bitops: Library to find appropriate bitwise library (closes #1395)
Kim Alvefur <zash@zash.se>
parents:
diff
changeset
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1 -- Compatibility layer for bitwise operations |
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util.bitops: Library to find appropriate bitwise library (closes #1395)
Kim Alvefur <zash@zash.se>
parents:
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2 |
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util.bitops: Library to find appropriate bitwise library (closes #1395)
Kim Alvefur <zash@zash.se>
parents:
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3 -- First try the bit32 lib |
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util.bitops: Library to find appropriate bitwise library (closes #1395)
Kim Alvefur <zash@zash.se>
parents:
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4 -- Lua 5.3 has it with compat enabled |
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util.bitops: Library to find appropriate bitwise library (closes #1395)
Kim Alvefur <zash@zash.se>
parents:
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5 -- Lua 5.2 has it by default |
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util.bitops: Library to find appropriate bitwise library (closes #1395)
Kim Alvefur <zash@zash.se>
parents:
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6 if _G.bit32 then |
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util.bitops: Library to find appropriate bitwise library (closes #1395)
Kim Alvefur <zash@zash.se>
parents:
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7 return _G.bit32; |
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util.bitops: Library to find appropriate bitwise library (closes #1395)
Kim Alvefur <zash@zash.se>
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8 else |
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util.bitops: Library to find appropriate bitwise library (closes #1395)
Kim Alvefur <zash@zash.se>
parents:
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9 -- Lua 5.1 may have it as a standalone module that can be installed |
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util.bitops: Library to find appropriate bitwise library (closes #1395)
Kim Alvefur <zash@zash.se>
parents:
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10 local ok, bitop = pcall(require, "bit32") |
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util.bitops: Library to find appropriate bitwise library (closes #1395)
Kim Alvefur <zash@zash.se>
parents:
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11 if ok then |
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util.bitops: Library to find appropriate bitwise library (closes #1395)
Kim Alvefur <zash@zash.se>
parents:
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12 return bitop; |
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util.bitops: Library to find appropriate bitwise library (closes #1395)
Kim Alvefur <zash@zash.se>
parents:
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13 end |
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util.bitops: Library to find appropriate bitwise library (closes #1395)
Kim Alvefur <zash@zash.se>
parents:
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14 end |
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util.bitops: Library to find appropriate bitwise library (closes #1395)
Kim Alvefur <zash@zash.se>
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15 |
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util.bitops: Library to find appropriate bitwise library (closes #1395)
Kim Alvefur <zash@zash.se>
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16 do |
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17 -- Lua 5.3 and 5.4 would be able to use native infix operators |
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18 local ok, bitop = pcall(require, "util.bit53") |
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util.bitops: Library to find appropriate bitwise library (closes #1395)
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19 if ok then |
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util.bitops: Library to find appropriate bitwise library (closes #1395)
Kim Alvefur <zash@zash.se>
parents:
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20 return bitop; |
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util.bitops: Library to find appropriate bitwise library (closes #1395)
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parents:
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21 end |
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22 end |
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23 |
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24 do |
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Kim Alvefur <zash@zash.se>
parents:
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25 -- Lastly, try the LuaJIT bitop library |
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Kim Alvefur <zash@zash.se>
parents:
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26 local ok, bitop = pcall(require, "bit") |
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Kim Alvefur <zash@zash.se>
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27 if ok then |
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28 return bitop; |
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29 end |
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Kim Alvefur <zash@zash.se>
parents:
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30 end |
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Kim Alvefur <zash@zash.se>
parents:
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31 |
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32 error "No bit module found. See https://prosody.im/doc/depends#bitop"; |