Untested attempt for autoupdate.tcl

# Autoupdater script v1.0 (c)2018 OUTsider <outsider@scarynet.org>
#
# Usage: Load this script prior to the scripts you want to autoupdate!
# In the scripts you want to update add this anywhere outside the functions:
# if {[info procs autoupdate:add]} { autoupdate:add <updateurl> }

package require http

# in case you need https
package require tls
::http::register https 443 ::tls::socket

set autoupdate ""
proc autoupdate:add {updateurl} {
    global autoupdate
    set scriptname [info script]
    lappend autoupdate(script) $scriptname
    set autoupdate(script,$scriptname) $updateurl
    putlog "\[AUTOUPDATE\] Added $scriptname with url: $updateurl to list."
}

bind time "* * * * *" - autoupdate:time
proc autoupdate:time {min hrs day mnt yrs} {
    global autoupdate

    #
    # put eventual throttles here or go for (u)timer constructs if it should not check every minute
    #

    set updated 0
    foreach script $autoupdate(script) {
        #read old file and get md5sum
        set fd [open $script r]
        set fdata [read $fd]
        close $fd
        set oldmd5 [md5 $fdata]

        #fetch new file from url
        set token [::http::geturl $autoupdate(script,$script)]
        if {[::http::ncode == 200]} {
            set data [::http::data $token]
            set newmd5 [md5 $data]

            #compare old with new md5sum, if same, file is not altered
            if {$oldmd5 == $newmd5} { continue }

            #fetch md5sum file and compare if present
            set token [::http::geturl "${autoupdate(script,$script)}.md5sum"]
            if {[::http::ncode == 200]} {
                set md5data [::http::data $token]
                if {[md5 $data] != $md5data} {
                    putlog "\[AUTOUPDATE\] ${autoupdate(script,$script)} failed MD5 check ([md5 $data] vs $md5data)"
                    continue
                }
            }

            # all checks passed, overwrite script
            set fd [open $script w]
            puts $fd $data
            close $fd
            incr updated
        } else {
            putlog "\[AUTOUPDATE\] ${autoupdate(script,$script)} returned HTTP Code [::http::ncode]"
        }
    }

    #some files got updated, rehash
    if {$updated > 0} {
        putlog "\[AUTOUPDATE\] $updated scripts have been updated"
        rehash
    }
}