updated base64.nim

1 files changed, 127 insertions, 127 deletions

diff --git a/lib/pure/base64.nim b/lib/pure/base64.nim
index 3d3cea25c..72c49142d 100644
--- a/lib/pure/base64.nim
+++ b/lib/pure/base64.nim
@@ -1,127 +1,127 @@
-#

-#

-#            Nim's Runtime Library

-#        (c) Copyright 2010 Andreas Rumpf

-#

-#    See the file "copying.txt", included in this

-#    distribution, for details about the copyright.

-#

-

-## This module implements a base64 encoder and decoder.

-

-const 

-  cb64 = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"

-

-template encodeInternal(s: expr, lineLen: int, newLine: string): stmt {.immediate.} = 

-  ## encodes `s` into base64 representation. After `lineLen` characters, a 

-  ## `newline` is added.

-  var total = ((len(s) + 2) div 3) * 4

-  var numLines = (total + lineLen - 1) div lineLen

-  if numLines > 0: inc(total, (numLines-1) * newLine.len)

-

-  result = newString(total)

-  var i = 0

-  var r = 0

-  var currLine = 0

-  while i < s.len - 2:

-    var a = ord(s[i])

-    var b = ord(s[i+1])

-    var c = ord(s[i+2])

-    result[r] = cb64[a shr 2]

-    result[r+1] = cb64[((a and 3) shl 4) or ((b and 0xF0) shr 4)]

-    result[r+2] = cb64[((b and 0x0F) shl 2) or ((c and 0xC0) shr 6)] 

-    result[r+3] = cb64[c and 0x3F] 

-    inc(r, 4)

-    inc(i, 3)

-    inc(currLine, 4)

-    if currLine >= lineLen and i != s.len-2: 

-      for x in items(newLine): 

-        result[r] = x

-        inc(r)

-      currLine = 0

-

-  if i < s.len-1:

-    var a = ord(s[i])

-    var b = ord(s[i+1])

-    result[r] = cb64[a shr 2]

-    result[r+1] = cb64[((a and 3) shl 4) or ((b and 0xF0) shr 4)]

-    result[r+2] = cb64[((b and 0x0F) shl 2)] 

-    result[r+3] = '='

-    if r+4 != result.len:

-      setLen(result, r+4)

-  elif i < s.len:

-    var a = ord(s[i])

-    result[r] = cb64[a shr 2]

-    result[r+1] = cb64[(a and 3) shl 4]

-    result[r+2] = '='

-    result[r+3] = '='

-    if r+4 != result.len:

-      setLen(result, r+4)

-  else:

-    #assert(r == result.len)

-

-proc encode*[T:TInteger|char](s: openarray[T], lineLen = 75, newLine="\13\10"): string = 

-  ## encodes `s` into base64 representation. After `lineLen` characters, a 

-  ## `newline` is added.

-  encodeInternal(s, lineLen, newLine)

-    

-proc encode*(s: string, lineLen = 75, newLine="\13\10"): string = 

-  ## encodes `s` into base64 representation. After `lineLen` characters, a 

-  ## `newline` is added.

-  encodeInternal(s, lineLen, newLine)

-  

-proc decodeByte(b: char): int {.inline.} = 

-  case b

-  of '+': result = ord('>')

-  of '0'..'9': result = ord(b) + 4

-  of 'A'..'Z': result = ord(b) - ord('A')

-  of 'a'..'z': result = ord(b) - 71

-  else: result = 63

-

-proc decode*(s: string): string = 

-  ## decodes a string in base64 representation back into its original form.

-  ## Whitespace is skipped.

-  const Whitespace = {' ', '\t', '\v', '\r', '\l', '\f'}

-  var total = ((len(s) + 3) div 4) * 3

-  # total is an upper bound, as we will skip arbitrary whitespace:

-  result = newString(total)

-

-  var i = 0

-  var r = 0

-  while true:

-    while s[i] in Whitespace: inc(i)

-    if i < s.len-3:

-      var a = s[i].decodeByte

-      var b = s[i+1].decodeByte

-      var c = s[i+2].decodeByte

-      var d = s[i+3].decodeByte

-      

-      result[r] = chr((a shl 2) and 0xff or ((b shr 4) and 0x03))

-      result[r+1] = chr((b shl 4) and 0xff or ((c shr 2) and 0x0F))

-      result[r+2] = chr((c shl 6) and 0xff or (d and 0x3F))

-      inc(r, 3)

-      inc(i, 4)

-    else: break

-  assert i == s.len

-  # adjust the length:

-  if i > 0 and s[i-1] == '=': 

-    dec(r)

-    if i > 1 and s[i-2] == '=': dec(r)

-  setLen(result, r)

-  

-when isMainModule:

-  assert encode("leasure.") == "bGVhc3VyZS4="

-  assert encode("easure.") == "ZWFzdXJlLg=="

-  assert encode("asure.") == "YXN1cmUu"

-  assert encode("sure.") == "c3VyZS4="

-  

-  const longText = """Man is distinguished, not only by his reason, but by this

-    singular passion from other animals, which is a lust of the mind, 

-    that by a perseverance of delight in the continued and indefatigable

-    generation of knowledge, exceeds the short vehemence of any carnal

-    pleasure."""

-  const tests = ["", "abc", "xyz", "man", "leasure.", "sure.", "easure.",

-                 "asure.", longText]

-  for t in items(tests):

-    assert decode(encode(t)) == t

-

+#
+#
+#            Nim's Runtime Library
+#        (c) Copyright 2010 Andreas Rumpf
+#
+#    See the file "copying.txt", included in this
+#    distribution, for details about the copyright.
+#
+
+## This module implements a base64 encoder and decoder.
+
+const 
+  cb64 = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"
+
+template encodeInternal(s: expr, lineLen: int, newLine: string): stmt {.immediate.} = 
+  ## encodes `s` into base64 representation. After `lineLen` characters, a 
+  ## `newline` is added.
+  var total = ((len(s) + 2) div 3) * 4
+  var numLines = (total + lineLen - 1) div lineLen
+  if numLines > 0: inc(total, (numLines-1) * newLine.len)
+
+  result = newString(total)
+  var i = 0
+  var r = 0
+  var currLine = 0
+  while i < s.len - 2:
+    var a = ord(s[i])
+    var b = ord(s[i+1])
+    var c = ord(s[i+2])
+    result[r] = cb64[a shr 2]
+    result[r+1] = cb64[((a and 3) shl 4) or ((b and 0xF0) shr 4)]
+    result[r+2] = cb64[((b and 0x0F) shl 2) or ((c and 0xC0) shr 6)] 
+    result[r+3] = cb64[c and 0x3F] 
+    inc(r, 4)
+    inc(i, 3)
+    inc(currLine, 4)
+    if currLine >= lineLen and i != s.len-2: 
+      for x in items(newLine): 
+        result[r] = x
+        inc(r)
+      currLine = 0
+
+  if i < s.len-1:
+    var a = ord(s[i])
+    var b = ord(s[i+1])
+    result[r] = cb64[a shr 2]
+    result[r+1] = cb64[((a and 3) shl 4) or ((b and 0xF0) shr 4)]
+    result[r+2] = cb64[((b and 0x0F) shl 2)] 
+    result[r+3] = '='
+    if r+4 != result.len:
+      setLen(result, r+4)
+  elif i < s.len:
+    var a = ord(s[i])
+    result[r] = cb64[a shr 2]
+    result[r+1] = cb64[(a and 3) shl 4]
+    result[r+2] = '='
+    result[r+3] = '='
+    if r+4 != result.len:
+      setLen(result, r+4)
+  else:
+    #assert(r == result.len)
+
+proc encode*[T:SomeInteger|char](s: openarray[T], lineLen = 75, newLine="\13\10"): string = 
+  ## encodes `s` into base64 representation. After `lineLen` characters, a 
+  ## `newline` is added.
+  encodeInternal(s, lineLen, newLine)
+    
+proc encode*(s: string, lineLen = 75, newLine="\13\10"): string = 
+  ## encodes `s` into base64 representation. After `lineLen` characters, a 
+  ## `newline` is added.
+  encodeInternal(s, lineLen, newLine)
+  
+proc decodeByte(b: char): int {.inline.} = 
+  case b
+  of '+': result = ord('>')
+  of '0'..'9': result = ord(b) + 4
+  of 'A'..'Z': result = ord(b) - ord('A')
+  of 'a'..'z': result = ord(b) - 71
+  else: result = 63
+
+proc decode*(s: string): string = 
+  ## decodes a string in base64 representation back into its original form.
+  ## Whitespace is skipped.
+  const Whitespace = {' ', '\t', '\v', '\r', '\l', '\f'}
+  var total = ((len(s) + 3) div 4) * 3
+  # total is an upper bound, as we will skip arbitrary whitespace:
+  result = newString(total)
+
+  var i = 0
+  var r = 0
+  while true:
+    while s[i] in Whitespace: inc(i)
+    if i < s.len-3:
+      var a = s[i].decodeByte
+      var b = s[i+1].decodeByte
+      var c = s[i+2].decodeByte
+      var d = s[i+3].decodeByte
+      
+      result[r] = chr((a shl 2) and 0xff or ((b shr 4) and 0x03))
+      result[r+1] = chr((b shl 4) and 0xff or ((c shr 2) and 0x0F))
+      result[r+2] = chr((c shl 6) and 0xff or (d and 0x3F))
+      inc(r, 3)
+      inc(i, 4)
+    else: break
+  assert i == s.len
+  # adjust the length:
+  if i > 0 and s[i-1] == '=': 
+    dec(r)
+    if i > 1 and s[i-2] == '=': dec(r)
+  setLen(result, r)
+  
+when isMainModule:
+  assert encode("leasure.") == "bGVhc3VyZS4="
+  assert encode("easure.") == "ZWFzdXJlLg=="
+  assert encode("asure.") == "YXN1cmUu"
+  assert encode("sure.") == "c3VyZS4="
+  
+  const longText = """Man is distinguished, not only by his reason, but by this
+    singular passion from other animals, which is a lust of the mind, 
+    that by a perseverance of delight in the continued and indefatigable
+    generation of knowledge, exceeds the short vehemence of any carnal
+    pleasure."""
+  const tests = ["", "abc", "xyz", "man", "leasure.", "sure.", "easure.",
+                 "asure.", longText]
+  for t in items(tests):
+    assert decode(encode(t)) == t
+