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-rw-r--r--vim/bundle/tlib_vim/autoload/tlib/hash.vim145
1 files changed, 145 insertions, 0 deletions
diff --git a/vim/bundle/tlib_vim/autoload/tlib/hash.vim b/vim/bundle/tlib_vim/autoload/tlib/hash.vim
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+++ b/vim/bundle/tlib_vim/autoload/tlib/hash.vim
@@ -0,0 +1,145 @@
+" @Author: Tom Link (mailto:micathom AT gmail com?subject=[vim])
+" @License: GPL (see http://www.gnu.org/licenses/gpl.txt)
+" @Revision: 276
+
+
+if !exists('g:tlib#hash#use_crc32')
+ let g:tlib#hash#use_crc32 = '' "{{{2
+endif
+
+
+if !exists('g:tlib#hash#use_adler32')
+ let g:tlib#hash#use_adler32 = '' "{{{2
+endif
+
+
+function! tlib#hash#CRC32B(chars) "{{{3
+ if !empty(g:tlib#hash#use_crc32)
+ let use = g:tlib#hash#use_crc32
+ elseif has('ruby')
+ let use = 'ruby'
+ else
+ let use = 'vim'
+ endif
+ if exists('*tlib#hash#CRC32B_'. use)
+ return tlib#hash#CRC32B_{use}(a:chars)
+ else
+ throw "Unknown version of tlib#hash#CRC32B: ". use
+ endif
+endf
+
+
+function! tlib#hash#CRC32B_ruby(chars) "{{{3
+ if has('ruby')
+ let rv = ''
+ if !exists('s:loaded_ruby_zlib')
+ ruby require 'zlib'
+ let s:loaded_ruby_zlib = 1
+ endif
+ ruby VIM::command('let rv = "%08X"' % Zlib.crc32(VIM::evaluate("a:chars")))
+ return rv
+ else
+ throw "tlib#hash#CRC32B_ruby not supported in this version of vim"
+ endif
+endf
+
+
+function! tlib#hash#CRC32B_vim(chars) "{{{3
+ if !exists('s:crc_table')
+ let cfile = tlib#persistent#Filename('tlib', 'crc_table', 1)
+ let s:crc_table = tlib#persistent#Value(cfile, 'tlib#hash#CreateCrcTable', 0)
+ endif
+ let xFFFF_FFFF = repeat([1], 32)
+ let crc = tlib#bitwise#XOR([0], xFFFF_FFFF, 'bits')
+ for char in split(a:chars, '\zs')
+ let octet = char2nr(char)
+ let r1 = tlib#bitwise#ShiftRight(crc, 8)
+ let i0 = tlib#bitwise#AND(crc, xFFFF_FFFF, 'bits')
+ let i1 = tlib#bitwise#XOR(i0, octet, 'bits')
+ let i2 = tlib#bitwise#Bits2Num(tlib#bitwise#AND(i1, 0xff, 'bits'))
+ let r2 = s:crc_table[i2]
+ let crc = tlib#bitwise#XOR(r1, r2, 'bits')
+ endfor
+ let crc = tlib#bitwise#XOR(crc, xFFFF_FFFF, 'bits')
+ let rv = tlib#bitwise#Bits2Num(crc, 16)
+ if len(rv) < 8
+ let rv = repeat('0', 8 - len(rv)) . rv
+ endif
+ return rv
+endf
+
+
+" :nodoc:
+function! tlib#hash#CreateCrcTable() "{{{3
+ let sum = 0.0
+ for exponent in [0, 1, 2, 4, 5, 7, 8, 10, 11, 12, 16, 22, 23, 26, 32]
+ let exp = tlib#bitwise#Bits2Num(repeat([0], 32 - exponent) + [1], 10.0)
+ let sum += exp
+ endfor
+ let divisor = tlib#bitwise#Num2Bits(sum)
+ let crc_table = []
+ for octet in range(256)
+ let remainder = tlib#bitwise#Num2Bits(octet)
+ for i in range(8)
+ if get(remainder, i) != 0
+ let remainder = tlib#bitwise#XOR(remainder, tlib#bitwise#ShiftLeft(divisor, i), "bits")
+ endif
+ endfor
+ let remainder = tlib#bitwise#ShiftRight(remainder, 8)
+ call add(crc_table, remainder)
+ endfor
+ return crc_table
+endf
+
+
+function! tlib#hash#Adler32(chars) "{{{3
+ if !empty(g:tlib#hash#use_adler32)
+ let use = g:tlib#hash#use_adler32
+ elseif exists('*or')
+ let use = 'vim'
+ else
+ let use = 'tlib'
+ endif
+ if exists('*tlib#hash#Adler32_'. use)
+ return tlib#hash#Adler32_{use}(a:chars)
+ else
+ throw "Unknown version of tlib#hash#Adler32_: ". use
+ endif
+endf
+
+
+function! tlib#hash#Adler32_vim(chars) "{{{3
+ if exists('*or')
+ let mod_adler = 65521
+ let a = 1
+ let b = 0
+ for index in range(len(a:chars))
+ let c = char2nr(a:chars[index])
+ let a = (a + c) % mod_adler
+ let b = (b + a) % mod_adler
+ endfor
+ let bb = b * float2nr(pow(2, 16))
+ let checksum = or(bb, a)
+ " TLogVAR checksum, a, b, bb
+ return printf("%08X", checksum)
+ else
+ throw "TLIB: Vim version doesn't support bitwise or()"
+ endif
+endf
+
+
+function! tlib#hash#Adler32_tlib(chars) "{{{3
+ let mod_adler = 65521
+ let a = 1
+ let b = 0
+ for index in range(len(a:chars))
+ let c = char2nr(a:chars[index])
+ let a = (a + c) % mod_adler
+ let b = (b + a) % mod_adler
+ endfor
+ let bb = tlib#bitwise#ShiftLeft(tlib#bitwise#Num2Bits(b), 16)
+ let checksum = tlib#bitwise#OR(bb, a, "bits")
+ return printf('%08s', tlib#bitwise#Bits2Num(checksum, 16))
+endf
+
+