/usr/share/tcltk/tcllib1.17/base64/yencode.tcl is in tcllib 1.17-dfsg-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 | # yencode.tcl - Copyright (C) 2002 Pat Thoyts <patthoyts@users.sourceforge.net>
#
# Provide a Tcl only implementation of yEnc encoding algorithm
#
# -------------------------------------------------------------------------
# See the file "license.terms" for information on usage and redistribution
# of this file, and for a DISCLAIMER OF ALL WARRANTIES.
# -------------------------------------------------------------------------
# FUTURE: Rework to allow switching between the tcl/critcl implementations.
package require Tcl 8.2; # tcl minimum version
catch {package require crc32}; # tcllib 1.1
catch {package require tcllibc}; # critcl enhancements for tcllib
namespace eval ::yencode {
namespace export encode decode yencode ydecode
}
# -------------------------------------------------------------------------
proc ::yencode::Encode {s} {
set r {}
binary scan $s c* d
foreach {c} $d {
set v [expr {($c + 42) % 256}]
if {$v == 0x00 || $v == 0x09 || $v == 0x0A
|| $v == 0x0D || $v == 0x3D} {
append r "="
set v [expr {($v + 64) % 256}]
}
append r [format %c $v]
}
return $r
}
proc ::yencode::Decode {s} {
if {[string length $s] == 0} {return ""}
set r {}
set esc 0
binary scan $s c* d
foreach c $d {
if {$c == 61 && $esc == 0} {
set esc 1
continue
}
set v [expr {($c - 42) % 256}]
if {$esc} {
set v [expr {($v - 64) % 256}]
set esc 0
}
append r [format %c $v]
}
return $r
}
# -------------------------------------------------------------------------
# C coded versions for critcl built base64c package
# -------------------------------------------------------------------------
if {[package provide critcl] != {}} {
namespace eval ::yencode {
critcl::ccode {
#include <string.h>
}
critcl::ccommand CEncode {dummy interp objc objv} {
Tcl_Obj *inputPtr, *resultPtr;
int len, rlen, xtra;
unsigned char *input, *p, *r, v;
if (objc != 2) {
Tcl_WrongNumArgs(interp, 1, objv, "data");
return TCL_ERROR;
}
/* fetch the input data */
inputPtr = objv[1];
input = Tcl_GetByteArrayFromObj(inputPtr, &len);
/* calculate the length of the encoded result */
rlen = len;
for (p = input; p < input + len; p++) {
v = (*p + 42) % 256;
if (v == 0 || v == 9 || v == 0x0A || v == 0x0D || v == 0x3D)
rlen++;
}
/* allocate the output buffer */
resultPtr = Tcl_NewObj();
r = Tcl_SetByteArrayLength(resultPtr, rlen);
/* encode the input */
for (p = input; p < input + len; p++) {
v = (*p + 42) % 256;
if (v == 0 || v == 9 || v == 0x0A || v == 0x0D || v == 0x3D) {
*r++ = '=';
v = (v + 64) % 256;
}
*r++ = v;
}
Tcl_SetObjResult(interp, resultPtr);
return TCL_OK;
}
critcl::ccommand CDecode {dummy interp objc objv} {
Tcl_Obj *inputPtr, *resultPtr;
int len, rlen, esc;
unsigned char *input, *p, *r, v;
if (objc != 2) {
Tcl_WrongNumArgs(interp, 1, objv, "data");
return TCL_ERROR;
}
/* fetch the input data */
inputPtr = objv[1];
input = Tcl_GetByteArrayFromObj(inputPtr, &len);
/* allocate the output buffer */
resultPtr = Tcl_NewObj();
r = Tcl_SetByteArrayLength(resultPtr, len);
/* encode the input */
for (p = input, esc = 0, rlen = 0; p < input + len; p++) {
if (*p == 61 && esc == 0) {
esc = 1;
continue;
}
v = (*p - 42) % 256;
if (esc) {
v = (v - 64) % 256;
esc = 0;
}
*r++ = v;
rlen++;
}
Tcl_SetByteArrayLength(resultPtr, rlen);
Tcl_SetObjResult(interp, resultPtr);
return TCL_OK;
}
}
}
if {[info command ::yencode::CEncode] != {}} {
interp alias {} ::yencode::encode {} ::yencode::CEncode
interp alias {} ::yencode::decode {} ::yencode::CDecode
} else {
interp alias {} ::yencode::encode {} ::yencode::Encode
interp alias {} ::yencode::decode {} ::yencode::Decode
}
# -------------------------------------------------------------------------
# Description:
# Pop the nth element off a list. Used in options processing.
#
proc ::yencode::Pop {varname {nth 0}} {
upvar $varname args
set r [lindex $args $nth]
set args [lreplace $args $nth $nth]
return $r
}
# -------------------------------------------------------------------------
proc ::yencode::yencode {args} {
array set opts {mode 0644 filename {} name {} line 128 crc32 1}
while {[string match -* [lindex $args 0]]} {
switch -glob -- [lindex $args 0] {
-f* { set opts(filename) [Pop args 1] }
-m* { set opts(mode) [Pop args 1] }
-n* { set opts(name) [Pop args 1] }
-l* { set opts(line) [Pop args 1] }
-c* { set opts(crc32) [Pop args 1] }
-- { Pop args ; break }
default {
set options [join [lsort [array names opts]] ", -"]
return -code error "bad option [lindex $args 0]:\
must be -$options"
}
}
Pop args
}
if {$opts(name) == {}} {
set opts(name) $opts(filename)
}
if {$opts(name) == {}} {
set opts(name) "data.dat"
}
if {! [string is boolean $opts(crc32)]} {
return -code error "bad option -crc32: argument must be true or false"
}
if {$opts(filename) != {}} {
set f [open $opts(filename) r]
fconfigure $f -translation binary
set data [read $f]
close $f
} else {
if {[llength $args] != 1} {
return -code error "wrong \# args: should be\
\"yencode ?options? -file name | data\""
}
set data [lindex $args 0]
}
set opts(size) [string length $data]
set r {}
append r [format "=ybegin line=%d size=%d name=%s" \
$opts(line) $opts(size) $opts(name)] "\n"
set ndx 0
while {$ndx < $opts(size)} {
set pln [string range $data $ndx [expr {$ndx + $opts(line) - 1}]]
set enc [encode $pln]
incr ndx [string length $pln]
append r $enc "\r\n"
}
append r [format "=yend size=%d" $ndx]
if {$opts(crc32)} {
append r " crc32=" [crc::crc32 -format %x $data]
}
return $r
}
# -------------------------------------------------------------------------
# Description:
# Perform ydecoding of a file or data. A file may contain more than one
# encoded data section so the result is a list where each element is a
# three element list of the provided filename, the file size and the
# data itself.
#
proc ::yencode::ydecode {args} {
array set opts {mode 0644 filename {} name default.bin}
while {[string match -* [lindex $args 0]]} {
switch -glob -- [lindex $args 0] {
-f* { set opts(filename) [Pop args 1] }
-- { Pop args ; break; }
default {
set options [join [lsort [array names opts]] ", -"]
return -code error "bad option [lindex $args 0]:\
must be -$opts"
}
}
Pop args
}
if {$opts(filename) != {}} {
set f [open $opts(filename) r]
set data [read $f]
close $f
} else {
if {[llength $args] != 1} {
return -code error "wrong \# args: should be\
\"ydecode ?options? -file name | data\""
}
set data [lindex $args 0]
}
set state false
set result {}
foreach {line} [split $data "\n"] {
set line [string trimright $line "\r\n"]
switch -exact -- $state {
false {
if {[string match "=ybegin*" $line]} {
regexp {line=(\d+)} $line -> opts(line)
regexp {size=(\d+)} $line -> opts(size)
regexp {name=(\d+)} $line -> opts(name)
if {$opts(name) == {}} {
set opts(name) default.bin
}
set state true
set r {}
}
}
true {
if {[string match "=yend*" $line]} {
set state false
lappend result [list $opts(name) $opts(size) $r]
} else {
append r [decode $line]
}
}
}
}
return $result
}
# -------------------------------------------------------------------------
package provide yencode 1.1.3
# -------------------------------------------------------------------------
#
# Local variables:
# mode: tcl
# indent-tabs-mode: nil
# End:
|