Add tcl/tk, so gitk and git-gui will work

[msysgit/historical-msysgit.git] / lib / tcl8.4 / http2.5 / http.tcl

# http.tcl --
#
#       Client-side HTTP for GET, POST, and HEAD commands. These routines can
#       be used in untrusted code that uses the Safesock security policy. These
#       procedures use a callback interface to avoid using vwait, which is not
#       defined in the safe base.
#
# See the file "license.terms" for information on usage and redistribution of
# this file, and for a DISCLAIMER OF ALL WARRANTIES.
#
# RCS: @(#) $Id: http.tcl,v 1.43.2.13 2006/10/06 05:56:48 hobbs Exp $

# Rough version history:
# 1.0   Old http_get interface.
# 2.0   http:: namespace and http::geturl.
# 2.1   Added callbacks to handle arriving data, and timeouts.
# 2.2   Added ability to fetch into a channel.
# 2.3   Added SSL support, and ability to post from a channel. This version
#       also cleans up error cases and eliminates the "ioerror" status in
#       favor of raising an error
# 2.4   Added -binary option to http::geturl and charset element to the state
#       array.

package require Tcl 8.4
# Keep this in sync with pkgIndex.tcl and with the install directories
# in Makefiles
package provide http 2.5.3

namespace eval http {
    variable http
    array set http {
        -accept */*
        -proxyhost {}
        -proxyport {}
        -proxyfilter http::ProxyRequired
        -urlencoding utf-8
    }
    set http(-useragent) "Tcl http client package [package provide http]"

    proc init {} {
        # Set up the map for quoting chars. RFC3986 Section 2.3 say percent
        # encode all except: "... percent-encoded octets in the ranges of ALPHA
        # (%41-%5A and %61-%7A), DIGIT (%30-%39), hyphen (%2D), period (%2E),
        # underscore (%5F), or tilde (%7E) should not be created by URI
        # producers ..."
        for {set i 0} {$i <= 256} {incr i} {
            set c [format %c $i]
            if {![string match {[-._~a-zA-Z0-9]} $c]} {
                set map($c) %[format %.2x $i]
            }
        }
        # These are handled specially
        set map(\n) %0d%0a
        variable formMap [array get map]
    }
    init

    variable urlTypes
    array set urlTypes {
        http    {80 ::socket}
    }

    variable encodings [string tolower [encoding names]]
    # This can be changed, but iso8859-1 is the RFC standard.
    variable defaultCharset "iso8859-1"

    # Force RFC 3986 strictness in geturl url verification?  Not for 8.4.x
    variable strict 0

    namespace export geturl config reset wait formatQuery register unregister
    # Useful, but not exported: data size status code
}

# http::register --
#
#     See documentaion for details.
#
# Arguments:
#     proto           URL protocol prefix, e.g. https
#     port            Default port for protocol
#     command         Command to use to create socket
# Results:
#     list of port and command that was registered.

proc http::register {proto port command} {
    variable urlTypes
    set urlTypes($proto) [list $port $command]
}

# http::unregister --
#
#     Unregisters URL protocol handler
#
# Arguments:
#     proto           URL protocol prefix, e.g. https
# Results:
#     list of port and command that was unregistered.

proc http::unregister {proto} {
    variable urlTypes
    if {![info exists urlTypes($proto)]} {
        return -code error "unsupported url type \"$proto\""
    }
    set old $urlTypes($proto)
    unset urlTypes($proto)
    return $old
}

# http::config --
#
#       See documentaion for details.
#
# Arguments:
#       args            Options parsed by the procedure.
# Results:
#        TODO

proc http::config {args} {
    variable http
    set options [lsort [array names http -*]]
    set usage [join $options ", "]
    if {[llength $args] == 0} {
        set result {}
        foreach name $options {
            lappend result $name $http($name)
        }
        return $result
    }
    set options [string map {- ""} $options]
    set pat ^-([join $options |])$
    if {[llength $args] == 1} {
        set flag [lindex $args 0]
        if {[regexp -- $pat $flag]} {
            return $http($flag)
        } else {
            return -code error "Unknown option $flag, must be: $usage"
        }
    } else {
        foreach {flag value} $args {
            if {[regexp -- $pat $flag]} {
                set http($flag) $value
            } else {
                return -code error "Unknown option $flag, must be: $usage"
            }
        }
    }
}

# http::Finish --
#
#       Clean up the socket and eval close time callbacks
#
# Arguments:
#       token       Connection token.
#       errormsg    (optional) If set, forces status to error.
#       skipCB      (optional) If set, don't call the -command callback. This
#                   is useful when geturl wants to throw an exception instead
#                   of calling the callback. That way, the same error isn't
#                   reported to two places.
#
# Side Effects:
#        Closes the socket

proc http::Finish { token {errormsg ""} {skipCB 0}} {
    variable $token
    upvar 0 $token state
    global errorInfo errorCode
    if {[string length $errormsg] != 0} {
        set state(error) [list $errormsg $errorInfo $errorCode]
        set state(status) error
    }
    catch {close $state(sock)}
    catch {after cancel $state(after)}
    if {[info exists state(-command)] && !$skipCB} {
        if {[catch {eval $state(-command) {$token}} err]} {
            if {[string length $errormsg] == 0} {
                set state(error) [list $err $errorInfo $errorCode]
                set state(status) error
            }
        }
        if {[info exists state(-command)]} {
            # Command callback may already have unset our state
            unset state(-command)
        }
    }
}

# http::reset --
#
#       See documentaion for details.
#
# Arguments:
#       token   Connection token.
#       why     Status info.
#
# Side Effects:
#       See Finish

proc http::reset { token {why reset} } {
    variable $token
    upvar 0 $token state
    set state(status) $why
    catch {fileevent $state(sock) readable {}}
    catch {fileevent $state(sock) writable {}}
    Finish $token
    if {[info exists state(error)]} {
        set errorlist $state(error)
        unset state
        eval ::error $errorlist
    }
}

# http::geturl --
#
#       Establishes a connection to a remote url via http.
#
# Arguments:
#       url             The http URL to goget.
#       args            Option value pairs. Valid options include:
#                               -blocksize, -validate, -headers, -timeout
# Results:
#       Returns a token for this connection. This token is the name of an array
#       that the caller should unset to garbage collect the state.

proc http::geturl { url args } {
    variable http
    variable urlTypes
    variable defaultCharset
    variable strict

    # Initialize the state variable, an array. We'll return the name of this
    # array as the token for the transaction.

    if {![info exists http(uid)]} {
        set http(uid) 0
    }
    set token [namespace current]::[incr http(uid)]
    variable $token
    upvar 0 $token state
    reset $token

    # Process command options.

    array set state {
        -binary         false
        -blocksize      8192
        -queryblocksize 8192
        -validate       0
        -headers        {}
        -timeout        0
        -type           application/x-www-form-urlencoded
        -queryprogress  {}
        state           header
        meta            {}
        coding          {}
        currentsize     0
        totalsize       0
        querylength     0
        queryoffset     0
        type            text/html
        body            {}
        status          ""
        http            ""
    }
    # These flags have their types verified [Bug 811170]
    array set type {
        -binary         boolean
        -blocksize      integer
        -queryblocksize integer
        -validate       boolean
        -timeout        integer
    }
    set state(charset)  $defaultCharset
    set options {-binary -blocksize -channel -command -handler -headers \
            -progress -query -queryblocksize -querychannel -queryprogress\
            -validate -timeout -type}
    set usage [join $options ", "]
    set options [string map {- ""} $options]
    set pat ^-([join $options |])$
    foreach {flag value} $args {
        if {[regexp $pat $flag]} {
            # Validate numbers
            if {[info exists type($flag)] && \
                    ![string is $type($flag) -strict $value]} {
                unset $token
                return -code error "Bad value for $flag ($value), must be $type($flag)"
            }
            set state($flag) $value
        } else {
            unset $token
            return -code error "Unknown option $flag, can be: $usage"
        }
    }

    # Make sure -query and -querychannel aren't both specified

    set isQueryChannel [info exists state(-querychannel)]
    set isQuery [info exists state(-query)]
    if {$isQuery && $isQueryChannel} {
        unset $token
        return -code error "Can't combine -query and -querychannel options!"
    }

    # Validate URL, determine the server host and port, and check proxy case
    # Recognize user:pass@host URLs also, although we do not do anything with
    # that info yet.

    # URLs have basically four parts.
    # First, before the colon, is the protocol scheme (e.g. http)
    # Second, for HTTP-like protocols, is the authority
    #   The authority is preceded by // and lasts up to (but not including)
    #   the following / and it identifies up to four parts, of which only one,
    #   the host, is required (if an authority is present at all). All other
    #   parts of the authority (user name, password, port number) are optional.
    # Third is the resource name, which is split into two parts at a ?
    #   The first part (from the single "/" up to "?") is the path, and the
    #   second part (from that "?" up to "#") is the query. *HOWEVER*, we do
    #   not need to separate them; we send the whole lot to the server.
    # Fourth is the fragment identifier, which is everything after the first
    #   "#" in the URL. The fragment identifier MUST NOT be sent to the server
    #   and indeed, we don't bother to validate it (it could be an error to
    #   pass it in here, but it's cheap to strip).
    #
    # An example of a URL that has all the parts:
    #   http://jschmoe:xyzzy@www.bogus.net:8000/foo/bar.tml?q=foo#changes
    # The "http" is the protocol, the user is "jschmoe", the password is
    # "xyzzy", the host is "www.bogus.net", the port is "8000", the path is
    # "/foo/bar.tml", the query is "q=foo", and the fragment is "changes".
    #
    # Note that the RE actually combines the user and password parts, as
    # recommended in RFC 3986. Indeed, that RFC states that putting passwords
    # in URLs is a Really Bad Idea, something with which I would agree utterly.
    # Also note that we do not currently support IPv6 addresses.
    #
    # From a validation perspective, we need to ensure that the parts of the
    # URL that are going to the server are correctly encoded.
    # This is only done if $::http::strict is true (default 0 for compat).

    set URLmatcher {(?x)                # this is _expanded_ syntax
        ^
        (?: (\w+) : ) ?                 # <protocol scheme>
        (?: //
            (?:
                (
                    [^@/\#?]+           # <userinfo part of authority>
                ) @
            )?
            ( [^/:\#?]+ )               # <host part of authority>
            (?: : (\d+) )?              # <port part of authority>
        )?
        ( / [^\#?]* (?: \? [^\#?]* )?)? # <path> (including query)
        (?: \# (.*) )?                  # <fragment>
        $
    }

    # Phase one: parse
    if {![regexp -- $URLmatcher $url -> proto user host port srvurl]} {
        unset $token
        return -code error "Unsupported URL: $url"
    }
    # Phase two: validate
    if {$host eq ""} {
        # Caller has to provide a host name; we do not have a "default host"
        # that would enable us to handle relative URLs.
        unset $token
        return -code error "Missing host part: $url"
        # Note that we don't check the hostname for validity here; if it's
        # invalid, we'll simply fail to resolve it later on.
    }
    if {$port ne "" && $port>65535} {
        unset $token
        return -code error "Invalid port number: $port"
    }
    # The user identification and resource identification parts of the URL can
    # have encoded characters in them; take care!
    if {$user ne ""} {
        # Check for validity according to RFC 3986, Appendix A
        set validityRE {(?xi)
            ^
            (?: [-\w.~!$&'()*+,;=:] | %[0-9a-f][0-9a-f] )+
            $
        }
        if {$strict && ![regexp -- $validityRE $user]} {
            unset $token
            # Provide a better error message in this error case
            if {[regexp {(?i)%(?![0-9a-f][0-9a-f]).?.?} $user bad]} {
                return -code error \
                        "Illegal encoding character usage \"$bad\" in URL user"
            }
            return -code error "Illegal characters in URL user"
        }
    }
    if {$srvurl ne ""} {
        # Check for validity according to RFC 3986, Appendix A
        set validityRE {(?xi)
            ^
            # Path part (already must start with / character)
            (?:       [-\w.~!$&'()*+,;=:@/]  | %[0-9a-f][0-9a-f] )*
            # Query part (optional, permits ? characters)
            (?: \? (?: [-\w.~!$&'()*+,;=:@/?] | %[0-9a-f][0-9a-f] )* )?
            $
        }
        if {$strict && ![regexp -- $validityRE $srvurl]} {
            unset $token
            # Provide a better error message in this error case
            if {[regexp {(?i)%(?![0-9a-f][0-9a-f])..} $srvurl bad]} {
                return -code error \
                        "Illegal encoding character usage \"$bad\" in URL path"
            }
            return -code error "Illegal characters in URL path"
        }
    } else {
        set srvurl /
    }
    if {[string length $proto] == 0} {
        set proto http
    }
    if {![info exists urlTypes($proto)]} {
        unset $token
        return -code error "Unsupported URL type \"$proto\""
    }
    set defport [lindex $urlTypes($proto) 0]
    set defcmd [lindex $urlTypes($proto) 1]

    if {[string length $port] == 0} {
        set port $defport
    }
    if {![catch {$http(-proxyfilter) $host} proxy]} {
        set phost [lindex $proxy 0]
        set pport [lindex $proxy 1]
    }

    # OK, now reassemble into a full URL
    set url ${proto}://
    if {$user ne ""} {
        append url $user
        append url @
    }
    append url $host
    if {$port != $defport} {
        append url : $port
    }
    append url $srvurl
    # Don't append the fragment!
    set state(url) $url

    # If a timeout is specified we set up the after event and arrange for an
    # asynchronous socket connection.

    if {$state(-timeout) > 0} {
        set state(after) [after $state(-timeout) \
                [list http::reset $token timeout]]
        set async -async
    } else {
        set async ""
    }

    # If we are using the proxy, we must pass in the full URL that includes
    # the server name.

    if {[info exists phost] && [string length $phost]} {
        set srvurl $url
        set conStat [catch {eval $defcmd $async {$phost $pport}} s]
    } else {
        set conStat [catch {eval $defcmd $async {$host $port}} s]
    }

    if {$conStat} {
        # Something went wrong while trying to establish the connection. Clean
        # up after events and such, but DON'T call the command callback (if
        # available) because we're going to throw an exception from here
        # instead.
        Finish $token "" 1
        cleanup $token
        return -code error $s
    }
    set state(sock) $s

    # Wait for the connection to complete.

    if {$state(-timeout) > 0} {
        fileevent $s writable [list http::Connect $token]
        http::wait $token

        if {$state(status) eq "error"} {
            # Something went wrong while trying to establish the connection.
            # Clean up after events and such, but DON'T call the command
            # callback (if available) because we're going to throw an
            # exception from here instead.
            set err [lindex $state(error) 0]
            cleanup $token
            return -code error $err
        } elseif {$state(status) ne "connect"} {
            # Likely to be connection timeout
            return $token
        }
        set state(status) ""
    }

    # Send data in cr-lf format, but accept any line terminators

    fconfigure $s -translation {auto crlf} -buffersize $state(-blocksize)

    # The following is disallowed in safe interpreters, but the socket is
    # already in non-blocking mode in that case.

    catch {fconfigure $s -blocking off}
    set how GET
    if {$isQuery} {
        set state(querylength) [string length $state(-query)]
        if {$state(querylength) > 0} {
            set how POST
            set contDone 0
        } else {
            # There's no query data.
            unset state(-query)
            set isQuery 0
        }
    } elseif {$state(-validate)} {
        set how HEAD
    } elseif {$isQueryChannel} {
        set how POST
        # The query channel must be blocking for the async Write to
        # work properly.
        fconfigure $state(-querychannel) -blocking 1 -translation binary
        set contDone 0
    }

    if {[catch {
        puts $s "$how $srvurl HTTP/1.0"
        puts $s "Accept: $http(-accept)"
        if {$port == $defport} {
            # Don't add port in this case, to handle broken servers. [Bug
            # 504508]
            puts $s "Host: $host"
        } else {
            puts $s "Host: $host:$port"
        }
        puts $s "User-Agent: $http(-useragent)"
        foreach {key value} $state(-headers) {
            set value [string map [list \n "" \r ""] $value]
            set key [string trim $key]
            if {$key eq "Content-Length"} {
                set contDone 1
                set state(querylength) $value
            }
            if {[string length $key]} {
                puts $s "$key: $value"
            }
        }
        if {$isQueryChannel && $state(querylength) == 0} {
            # Try to determine size of data in channel. If we cannot seek, the
            # surrounding catch will trap us

            set start [tell $state(-querychannel)]
            seek $state(-querychannel) 0 end
            set state(querylength) \
                    [expr {[tell $state(-querychannel)] - $start}]
            seek $state(-querychannel) $start
        }

        # Flush the request header and set up the fileevent that will either
        # push the POST data or read the response.
        #
        # fileevent note:
        #
        # It is possible to have both the read and write fileevents active at
        # this point. The only scenario it seems to affect is a server that
        # closes the connection without reading the POST data. (e.g., early
        # versions TclHttpd in various error cases). Depending on the platform,
        # the client may or may not be able to get the response from the server
        # because of the error it will get trying to write the post data.
        # Having both fileevents active changes the timing and the behavior,
        # but no two platforms (among Solaris, Linux, and NT) behave the same,
        # and none behave all that well in any case. Servers should always read
        # their POST data if they expect the client to read their response.

        if {$isQuery || $isQueryChannel} {
            puts $s "Content-Type: $state(-type)"
            if {!$contDone} {
                puts $s "Content-Length: $state(querylength)"
            }
            puts $s ""
            fconfigure $s -translation {auto binary}
            fileevent $s writable [list http::Write $token]
        } else {
            puts $s ""
            flush $s
            fileevent $s readable [list http::Event $token]
        }

        if {! [info exists state(-command)]} {
            # geturl does EVERYTHING asynchronously, so if the user calls it
            # synchronously, we just do a wait here.

            wait $token
            if {$state(status) eq "error"} {
                # Something went wrong, so throw the exception, and the
                # enclosing catch will do cleanup.
                return -code error [lindex $state(error) 0]
            }
        }
    } err]} {
        # The socket probably was never connected, or the connection dropped
        # later.

        # Clean up after events and such, but DON'T call the command callback
        # (if available) because we're going to throw an exception from here
        # instead.

        # if state(status) is error, it means someone's already called Finish
        # to do the above-described clean up.
        if {$state(status) eq "error"} {
            Finish $token $err 1
        }
        cleanup $token
        return -code error $err
    }

    return $token
}

# Data access functions:
# Data - the URL data
# Status - the transaction status: ok, reset, eof, timeout
# Code - the HTTP transaction code, e.g., 200
# Size - the size of the URL data

proc http::data {token} {
    variable $token
    upvar 0 $token state
    return $state(body)
}
proc http::status {token} {
    variable $token
    upvar 0 $token state
    return $state(status)
}
proc http::code {token} {
    variable $token
    upvar 0 $token state
    return $state(http)
}
proc http::ncode {token} {
    variable $token
    upvar 0 $token state
    if {[regexp {[0-9]{3}} $state(http) numeric_code]} {
        return $numeric_code
    } else {
        return $state(http)
    }
}
proc http::size {token} {
    variable $token
    upvar 0 $token state
    return $state(currentsize)
}

proc http::error {token} {
    variable $token
    upvar 0 $token state
    if {[info exists state(error)]} {
        return $state(error)
    }
    return ""
}

# http::cleanup
#
#       Garbage collect the state associated with a transaction
#
# Arguments
#       token   The token returned from http::geturl
#
# Side Effects
#       unsets the state array

proc http::cleanup {token} {
    variable $token
    upvar 0 $token state
    if {[info exists state]} {
        unset state
    }
}

# http::Connect
#
#       This callback is made when an asyncronous connection completes.
#
# Arguments
#       token   The token returned from http::geturl
#
# Side Effects
#       Sets the status of the connection, which unblocks
#       the waiting geturl call

proc http::Connect {token} {
    variable $token
    upvar 0 $token state
    global errorInfo errorCode
    if {[eof $state(sock)] ||
        [string length [fconfigure $state(sock) -error]]} {
            Finish $token "connect failed [fconfigure $state(sock) -error]" 1
    } else {
        set state(status) connect
        fileevent $state(sock) writable {}
    }
    return
}

# http::Write
#
#       Write POST query data to the socket
#
# Arguments
#       token   The token for the connection
#
# Side Effects
#       Write the socket and handle callbacks.

proc http::Write {token} {
    variable $token
    upvar 0 $token state
    set s $state(sock)

    # Output a block.  Tcl will buffer this if the socket blocks
    set done 0
    if {[catch {
        # Catch I/O errors on dead sockets

        if {[info exists state(-query)]} {
            # Chop up large query strings so queryprogress callback can give
            # smooth feedback.

            puts -nonewline $s \
                    [string range $state(-query) $state(queryoffset) \
                    [expr {$state(queryoffset) + $state(-queryblocksize) - 1}]]
            incr state(queryoffset) $state(-queryblocksize)
            if {$state(queryoffset) >= $state(querylength)} {
                set state(queryoffset) $state(querylength)
                set done 1
            }
        } else {
            # Copy blocks from the query channel

            set outStr [read $state(-querychannel) $state(-queryblocksize)]
            puts -nonewline $s $outStr
            incr state(queryoffset) [string length $outStr]
            if {[eof $state(-querychannel)]} {
                set done 1
            }
        }
    } err]} {
        # Do not call Finish here, but instead let the read half of the socket
        # process whatever server reply there is to get.

        set state(posterror) $err
        set done 1
    }
    if {$done} {
        catch {flush $s}
        fileevent $s writable {}
        fileevent $s readable [list http::Event $token]
    }

    # Callback to the client after we've completely handled everything.

    if {[string length $state(-queryprogress)]} {
        eval $state(-queryprogress) [list $token $state(querylength)\
                $state(queryoffset)]
    }
}

# http::Event
#
#       Handle input on the socket
#
# Arguments
#       token   The token returned from http::geturl
#
# Side Effects
#       Read the socket and handle callbacks.

proc http::Event {token} {
    variable $token
    upvar 0 $token state
    set s $state(sock)

     if {[eof $s]} {
        Eof $token
        return
    }
    if {$state(state) eq "header"} {
        if {[catch {gets $s line} n]} {
            Finish $token $n
        } elseif {$n == 0} {
            variable encodings
            set state(state) body
            if {$state(-binary) || ![string match -nocase text* $state(type)]
                    || [string match *gzip* $state(coding)]
                    || [string match *compress* $state(coding)]} {
                # Turn off conversions for non-text data
                fconfigure $s -translation binary
                if {[info exists state(-channel)]} {
                    fconfigure $state(-channel) -translation binary
                }
            } else {
                # If we are getting text, set the incoming channel's encoding
                # correctly. iso8859-1 is the RFC default, but this could be
                # any IANA charset. However, we only know how to convert what
                # we have encodings for.
                set idx [lsearch -exact $encodings \
                        [string tolower $state(charset)]]
                if {$idx >= 0} {
                    fconfigure $s -encoding [lindex $encodings $idx]
                }
            }
            if {[info exists state(-channel)] && \
                    ![info exists state(-handler)]} {
                # Initiate a sequence of background fcopies
                fileevent $s readable {}
                CopyStart $s $token
            }
        } elseif {$n > 0} {
            if {[regexp -nocase {^content-type:(.+)$} $line x type]} {
                set state(type) [string trim $type]
                # grab the optional charset information
                regexp -nocase {charset\s*=\s*(\S+)} $type x state(charset)
            }
            if {[regexp -nocase {^content-length:(.+)$} $line x length]} {
                set state(totalsize) [string trim $length]
            }
            if {[regexp -nocase {^content-encoding:(.+)$} $line x coding]} {
                set state(coding) [string trim $coding]
            }
            if {[regexp -nocase {^([^:]+):(.+)$} $line x key value]} {
                lappend state(meta) $key [string trim $value]
            } elseif {[string match HTTP* $line]} {
                set state(http) $line
            }
        }
    } else {
        if {[catch {
            if {[info exists state(-handler)]} {
                set n [eval $state(-handler) {$s $token}]
            } else {
                set block [read $s $state(-blocksize)]
                set n [string length $block]
                if {$n >= 0} {
                    append state(body) $block
                }
            }
            if {$n >= 0} {
                incr state(currentsize) $n
            }
        } err]} {
            Finish $token $err
        } else {
            if {[info exists state(-progress)]} {
                eval $state(-progress) \
                        {$token $state(totalsize) $state(currentsize)}
            }
        }
    }
}

# http::CopyStart
#
#       Error handling wrapper around fcopy
#
# Arguments
#       s       The socket to copy from
#       token   The token returned from http::geturl
#
# Side Effects
#       This closes the connection upon error

proc http::CopyStart {s token} {
    variable $token
    upvar 0 $token state
    if {[catch {
        fcopy $s $state(-channel) -size $state(-blocksize) -command \
            [list http::CopyDone $token]
    } err]} {
        Finish $token $err
    }
}

# http::CopyDone
#
#       fcopy completion callback
#
# Arguments
#       token   The token returned from http::geturl
#       count   The amount transfered
#
# Side Effects
#       Invokes callbacks

proc http::CopyDone {token count {error {}}} {
    variable $token
    upvar 0 $token state
    set s $state(sock)
    incr state(currentsize) $count
    if {[info exists state(-progress)]} {
        eval $state(-progress) {$token $state(totalsize) $state(currentsize)}
    }
    # At this point the token may have been reset
    if {[string length $error]} {
        Finish $token $error
    } elseif {[catch {eof $s} iseof] || $iseof} {
        Eof $token
    } else {
        CopyStart $s $token
    }
}

# http::Eof
#
#       Handle eof on the socket
#
# Arguments
#       token   The token returned from http::geturl
#
# Side Effects
#       Clean up the socket

proc http::Eof {token} {
    variable $token
    upvar 0 $token state
    if {$state(state) eq "header"} {
        # Premature eof
        set state(status) eof
    } else {
        set state(status) ok
    }
    set state(state) eof
    Finish $token
}

# http::wait --
#
#       See documentaion for details.
#
# Arguments:
#       token   Connection token.
#
# Results:
#        The status after the wait.

proc http::wait {token} {
    variable $token
    upvar 0 $token state

    if {![info exists state(status)] || [string length $state(status)] == 0} {
        # We must wait on the original variable name, not the upvar alias
        vwait $token\(status)
    }

    return $state(status)
}

# http::formatQuery --
#
#       See documentaion for details. Call http::formatQuery with an even
#       number of arguments, where the first is a name, the second is a value,
#       the third is another name, and so on.
#
# Arguments:
#       args    A list of name-value pairs.
#
# Results:
#       TODO

proc http::formatQuery {args} {
    set result ""
    set sep ""
    foreach i $args {
        append result $sep [mapReply $i]
        if {$sep eq "="} {
            set sep &
        } else {
            set sep =
        }
    }
    return $result
}

# http::mapReply --
#
#       Do x-www-urlencoded character mapping
#
# Arguments:
#       string  The string the needs to be encoded
#
# Results:
#       The encoded string

proc http::mapReply {string} {
    variable http
    variable formMap

    # The spec says: "non-alphanumeric characters are replaced by '%HH'". Use
    # a pre-computed map and [string map] to do the conversion (much faster
    # than [regsub]/[subst]). [Bug 1020491]

    if {$http(-urlencoding) ne ""} {
        set string [encoding convertto $http(-urlencoding) $string]
        return [string map $formMap $string]
    }
    set converted [string map $formMap $string]
    if {[string match "*\[\u0100-\uffff\]*" $converted]} {
        regexp {[\u0100-\uffff]} $converted badChar
        # Return this error message for maximum compatability... :^/
        return -code error \
            "can't read \"formMap($badChar)\": no such element in array"
    }
    return $converted
}

# http::ProxyRequired --
#       Default proxy filter.
#
# Arguments:
#       host    The destination host
#
# Results:
#       The current proxy settings

proc http::ProxyRequired {host} {
    variable http
    if {[info exists http(-proxyhost)] && [string length $http(-proxyhost)]} {
        if {![info exists http(-proxyport)] || \
                ![string length $http(-proxyport)]} {
            set http(-proxyport) 8080
        }
        return [list $http(-proxyhost) $http(-proxyport)]
    }
}