Attachment "base64.tcl.patch" to
ticket [1869943fff]
added by
billiob
2008-01-12 21:06:09.
--- base64.tcl 2007/07/29 16:21:31
+++ base64.tcl 2008/01/12 00:00:22
@@ -280,6 +280,8 @@
binary scan $string c* X
set output ""
+
+ set nums ""
foreach x $X {
set bits [lindex $base64 $x]
@@ -298,17 +300,20 @@
# padding characters. If x=={}, we have 12 bits of input
# (enough for 1 8-bit output). If x!={}, we have 18 bits of
# input (enough for 2 8-bit outputs).
-
- foreach {v w z} $nums break
- set a [expr {($v << 2) | (($w & 0x30) >> 4)}]
-
- if {$z == {}} {
- append output [binary format c $a ]
- } else {
- set b [expr {(($w & 0xF) << 4) | (($z & 0x3C) >> 2)}]
- append output [binary format cc $a $b]
- }
- break
+ # if string is just characters nor part of the Base64 alphabet + '='
+ # then nums is still "".
+ if { $nums != ""} {
+ foreach {v w z} $nums break
+ set a [expr {($v << 2) | (($w & 0x30) >> 4)}]
+
+ if {$z == {}} {
+ append output [binary format c $a ]
+ } else {
+ set b [expr {(($w & 0xF) << 4) | (($z & 0x3C) >> 2)}]
+ append output [binary format cc $a $b]
+ }
+ break
+ }
} else {
# RFC 2045 says that line breaks and other characters not part
# of the Base64 alphabet must be ignored, and that the decoder
