freebsd-nq/contrib/tcl/library/init.tcl
Poul-Henning Kamp 8569730d6b Import tcl7.5p1
1996-09-18 14:12:34 +00:00

552 lines
16 KiB
Tcl

# init.tcl --
#
# Default system startup file for Tcl-based applications. Defines
# "unknown" procedure and auto-load facilities.
#
# SCCS: @(#) init.tcl 1.57 96/07/23 08:53:03
#
# Copyright (c) 1991-1993 The Regents of the University of California.
# Copyright (c) 1994-1996 Sun Microsystems, Inc.
#
# See the file "license.terms" for information on usage and redistribution
# of this file, and for a DISCLAIMER OF ALL WARRANTIES.
#
if {[info commands package] == ""} {
error "version mismatch: library\nscripts expect Tcl version 7.5b1 or later but the loaded version is\nonly [info patchlevel]"
}
package require -exact Tcl 7.5
if [catch {set auto_path $env(TCLLIBPATH)}] {
set auto_path ""
}
if {[lsearch -exact $auto_path [info library]] < 0} {
lappend auto_path [info library]
}
package unknown tclPkgUnknown
if {[info commands exec] == ""} {
# Some machines, such as the Macintosh, do not have exec. Also, on all
# platforms, safe interpreters do not have exec.
set auto_noexec 1
}
set errorCode ""
set errorInfo ""
# unknown --
# This procedure is called when a Tcl command is invoked that doesn't
# exist in the interpreter. It takes the following steps to make the
# command available:
#
# 1. See if the autoload facility can locate the command in a
# Tcl script file. If so, load it and execute it.
# 2. If the command was invoked interactively at top-level:
# (a) see if the command exists as an executable UNIX program.
# If so, "exec" the command.
# (b) see if the command requests csh-like history substitution
# in one of the common forms !!, !<number>, or ^old^new. If
# so, emulate csh's history substitution.
# (c) see if the command is a unique abbreviation for another
# command. If so, invoke the command.
#
# Arguments:
# args - A list whose elements are the words of the original
# command, including the command name.
proc unknown args {
global auto_noexec auto_noload env unknown_pending tcl_interactive
global errorCode errorInfo
# Save the values of errorCode and errorInfo variables, since they
# may get modified if caught errors occur below. The variables will
# be restored just before re-executing the missing command.
set savedErrorCode $errorCode
set savedErrorInfo $errorInfo
set name [lindex $args 0]
if ![info exists auto_noload] {
#
# Make sure we're not trying to load the same proc twice.
#
if [info exists unknown_pending($name)] {
unset unknown_pending($name)
if {[array size unknown_pending] == 0} {
unset unknown_pending
}
return -code error "self-referential recursion in \"unknown\" for command \"$name\"";
}
set unknown_pending($name) pending;
set ret [catch {auto_load $name} msg]
unset unknown_pending($name);
if {$ret != 0} {
return -code $ret -errorcode $errorCode \
"error while autoloading \"$name\": $msg"
}
if ![array size unknown_pending] {
unset unknown_pending
}
if $msg {
set errorCode $savedErrorCode
set errorInfo $savedErrorInfo
set code [catch {uplevel $args} msg]
if {$code == 1} {
#
# Strip the last five lines off the error stack (they're
# from the "uplevel" command).
#
set new [split $errorInfo \n]
set new [join [lrange $new 0 [expr [llength $new] - 6]] \n]
return -code error -errorcode $errorCode \
-errorinfo $new $msg
} else {
return -code $code $msg
}
}
}
if {([info level] == 1) && ([info script] == "") \
&& [info exists tcl_interactive] && $tcl_interactive} {
if ![info exists auto_noexec] {
if [auto_execok $name] {
set errorCode $savedErrorCode
set errorInfo $savedErrorInfo
return [uplevel exec >&@stdout <@stdin $args]
}
}
set errorCode $savedErrorCode
set errorInfo $savedErrorInfo
if {$name == "!!"} {
return [uplevel {history redo}]
}
if [regexp {^!(.+)$} $name dummy event] {
return [uplevel [list history redo $event]]
}
if [regexp {^\^([^^]*)\^([^^]*)\^?$} $name dummy old new] {
return [uplevel [list history substitute $old $new]]
}
set cmds [info commands $name*]
if {[llength $cmds] == 1} {
return [uplevel [lreplace $args 0 0 $cmds]]
}
if {[llength $cmds] != 0} {
if {$name == ""} {
return -code error "empty command name \"\""
} else {
return -code error \
"ambiguous command name \"$name\": [lsort $cmds]"
}
}
}
return -code error "invalid command name \"$name\""
}
# auto_load --
# Checks a collection of library directories to see if a procedure
# is defined in one of them. If so, it sources the appropriate
# library file to create the procedure. Returns 1 if it successfully
# loaded the procedure, 0 otherwise.
#
# Arguments:
# cmd - Name of the command to find and load.
proc auto_load cmd {
global auto_index auto_oldpath auto_path env errorInfo errorCode
if [info exists auto_index($cmd)] {
uplevel #0 $auto_index($cmd)
return [expr {[info commands $cmd] != ""}]
}
if ![info exists auto_path] {
return 0
}
if [info exists auto_oldpath] {
if {$auto_oldpath == $auto_path} {
return 0
}
}
set auto_oldpath $auto_path
for {set i [expr [llength $auto_path] - 1]} {$i >= 0} {incr i -1} {
set dir [lindex $auto_path $i]
set f ""
if [catch {set f [open [file join $dir tclIndex]]}] {
continue
}
set error [catch {
set id [gets $f]
if {$id == "# Tcl autoload index file, version 2.0"} {
eval [read $f]
} elseif {$id == "# Tcl autoload index file: each line identifies a Tcl"} {
while {[gets $f line] >= 0} {
if {([string index $line 0] == "#")
|| ([llength $line] != 2)} {
continue
}
set name [lindex $line 0]
set auto_index($name) \
"source [file join $dir [lindex $line 1]]"
}
} else {
error "[file join $dir tclIndex] isn't a proper Tcl index file"
}
} msg]
if {$f != ""} {
close $f
}
if $error {
error $msg $errorInfo $errorCode
}
}
if [info exists auto_index($cmd)] {
uplevel #0 $auto_index($cmd)
if {[info commands $cmd] != ""} {
return 1
}
}
return 0
}
if {[string compare $tcl_platform(platform) windows] == 0} {
# auto_execok --
#
# Returns 1 if there's an executable in the current path for the
# given name, 0 otherwise. Builds an associative array auto_execs
# that caches information about previous checks, for speed.
#
# Arguments:
# name - Name of a command.
# Windows version.
#
# Note that info executable doesn't work under Windows, so we have to
# look for files with .exe, .com, or .bat extensions. Also, the path
# may be in the Path or PATH environment variables, and path
# components are separated with semicolons, not colons as under Unix.
#
proc auto_execok name {
global auto_execs env
if [info exists auto_execs($name)] {
return $auto_execs($name)
}
set auto_execs($name) 0
if {[file pathtype $name] != "relative"} {
foreach ext {{} .exe .bat .cmd} {
if {[file exists ${name}${ext}]
&& ![file isdirectory ${name}${ext}]} {
set auto_execs($name) 1
}
}
return $auto_execs($name)
}
if {! [info exists env(PATH)]} {
if [info exists env(Path)] {
set path $env(Path)
} else {
return 0
}
} else {
set path $env(PATH)
}
foreach dir [split $path {;}] {
if {$dir == ""} {
set dir .
}
foreach ext {{} .exe .bat .cmd} {
set file [file join $dir ${name}${ext}]
if {[file exists $file] && ![file isdirectory $file]} {
set auto_execs($name) 1
return 1
}
}
}
return 0
}
} else {
# Unix version.
#
proc auto_execok name {
global auto_execs env
if [info exists auto_execs($name)] {
return $auto_execs($name)
}
set auto_execs($name) 0
if {[file pathtype $name] != "relative"} {
if {[file executable $name] && ![file isdirectory $name]} {
set auto_execs($name) 1
}
return $auto_execs($name)
}
foreach dir [split $env(PATH) :] {
if {$dir == ""} {
set dir .
}
set file [file join $dir $name]
if {[file executable $file] && ![file isdirectory $file]} {
set auto_execs($name) 1
return 1
}
}
return 0
}
}
# auto_reset --
# Destroy all cached information for auto-loading and auto-execution,
# so that the information gets recomputed the next time it's needed.
# Also delete any procedures that are listed in the auto-load index
# except those defined in this file.
#
# Arguments:
# None.
proc auto_reset {} {
global auto_execs auto_index auto_oldpath
foreach p [info procs] {
if {[info exists auto_index($p)] && ![string match auto_* $p]
&& ([lsearch -exact {unknown pkg_mkIndex tclPkgSetup
tclPkgUnknown} $p] < 0)} {
rename $p {}
}
}
catch {unset auto_execs}
catch {unset auto_index}
catch {unset auto_oldpath}
}
# auto_mkindex --
# Regenerate a tclIndex file from Tcl source files. Takes as argument
# the name of the directory in which the tclIndex file is to be placed,
# followed by any number of glob patterns to use in that directory to
# locate all of the relevant files.
#
# Arguments:
# dir - Name of the directory in which to create an index.
# args - Any number of additional arguments giving the
# names of files within dir. If no additional
# are given auto_mkindex will look for *.tcl.
proc auto_mkindex {dir args} {
global errorCode errorInfo
set oldDir [pwd]
cd $dir
set dir [pwd]
append index "# Tcl autoload index file, version 2.0\n"
append index "# This file is generated by the \"auto_mkindex\" command\n"
append index "# and sourced to set up indexing information for one or\n"
append index "# more commands. Typically each line is a command that\n"
append index "# sets an element in the auto_index array, where the\n"
append index "# element name is the name of a command and the value is\n"
append index "# a script that loads the command.\n\n"
if {$args == ""} {
set args *.tcl
}
foreach file [eval glob $args] {
set f ""
set error [catch {
set f [open $file]
while {[gets $f line] >= 0} {
if [regexp {^proc[ ]+([^ ]*)} $line match procName] {
append index "set [list auto_index($procName)]"
append index " \[list source \[file join \$dir [list $file]\]\]\n"
}
}
close $f
} msg]
if $error {
set code $errorCode
set info $errorInfo
catch {close $f}
cd $oldDir
error $msg $info $code
}
}
set f ""
set error [catch {
set f [open tclIndex w]
puts $f $index nonewline
close $f
cd $oldDir
} msg]
if $error {
set code $errorCode
set info $errorInfo
catch {close $f}
cd $oldDir
error $msg $info $code
}
}
# pkg_mkIndex --
# This procedure creates a package index in a given directory. The
# package index consists of a "pkgIndex.tcl" file whose contents are
# a Tcl script that sets up package information with "package require"
# commands. The commands describe all of the packages defined by the
# files given as arguments.
#
# Arguments:
# dir - Name of the directory in which to create the index.
# args - Any number of additional arguments, each giving
# a glob pattern that matches the names of one or
# more shared libraries or Tcl script files in
# dir.
proc pkg_mkIndex {dir args} {
global errorCode errorInfo
append index "# Tcl package index file, version 1.0\n"
append index "# This file is generated by the \"pkg_mkIndex\" command\n"
append index "# and sourced either when an application starts up or\n"
append index "# by a \"package unknown\" script. It invokes the\n"
append index "# \"package ifneeded\" command to set up package-related\n"
append index "# information so that packages will be loaded automatically\n"
append index "# in response to \"package require\" commands. When this\n"
append index "# script is sourced, the variable \$dir must contain the\n"
append index "# full path name of this file's directory.\n"
set oldDir [pwd]
cd $dir
foreach file [eval glob $args] {
# For each file, figure out what commands and packages it provides.
# To do this, create a child interpreter, load the file into the
# interpreter, and get a list of the new commands and packages
# that are defined. Define an empty "package unknown" script so
# that there are no recursive package inclusions.
set c [interp create]
# If Tk is loaded in the parent interpreter, load it into the
# child also, in case the extension depends on it.
foreach pkg [info loaded] {
if {[lindex $pkg 1] == "Tk"} {
$c eval {set argv {-geometry +0+0}}
load [lindex $pkg 0] Tk $c
break
}
}
$c eval [list set file $file]
if [catch {
$c eval {
proc dummy args {}
package unknown dummy
set origCmds [info commands]
set dir "" ;# in case file is pkgIndex.tcl
set pkgs ""
# Try to load the file if it has the shared library extension,
# otherwise source it. It's important not to try to load
# files that aren't shared libraries, because on some systems
# (like SunOS) the loader will abort the whole application
# when it gets an error.
if {[string compare [file extension $file] \
[info sharedlibextension]] == 0} {
# The "file join ." command below is necessary. Without
# it, if the file name has no \'s and we're on UNIX, the
# load command will invoke the LD_LIBRARY_PATH search
# mechanism, which could cause the wrong file to be used.
load [file join . $file]
set type load
} else {
source $file
set type source
}
foreach i [info commands] {
set cmds($i) 1
}
foreach i $origCmds {
catch {unset cmds($i)}
}
foreach i [package names] {
if {([string compare [package provide $i] ""] != 0)
&& ([string compare $i Tcl] != 0)
&& ([string compare $i Tk] != 0)} {
lappend pkgs [list $i [package provide $i]]
}
}
}
} msg] {
puts "error while loading or sourcing $file: $msg"
}
foreach pkg [$c eval set pkgs] {
lappend files($pkg) [list $file [$c eval set type] \
[lsort [$c eval array names cmds]]]
}
interp delete $c
}
foreach pkg [lsort [array names files]] {
append index "\npackage ifneeded $pkg\
\[list tclPkgSetup \$dir [lrange $pkg 0 0] [lrange $pkg 1 1]\
[list $files($pkg)]\]"
}
set f [open pkgIndex.tcl w]
puts $f $index
close $f
cd $oldDir
}
# tclPkgSetup --
# This is a utility procedure use by pkgIndex.tcl files. It is invoked
# as part of a "package ifneeded" script. It calls "package provide"
# to indicate that a package is available, then sets entries in the
# auto_index array so that the package's files will be auto-loaded when
# the commands are used.
#
# Arguments:
# dir - Directory containing all the files for this package.
# pkg - Name of the package (no version number).
# version - Version number for the package, such as 2.1.3.
# files - List of files that constitute the package. Each
# element is a sub-list with three elements. The first
# is the name of a file relative to $dir, the second is
# "load" or "source", indicating whether the file is a
# loadable binary or a script to source, and the third
# is a list of commands defined by this file.
proc tclPkgSetup {dir pkg version files} {
global auto_index
package provide $pkg $version
foreach fileInfo $files {
set f [lindex $fileInfo 0]
set type [lindex $fileInfo 1]
foreach cmd [lindex $fileInfo 2] {
if {$type == "load"} {
set auto_index($cmd) [list load [file join $dir $f] $pkg]
} else {
set auto_index($cmd) [list source [file join $dir $f]]
}
}
}
}
# tclPkgUnknown --
# This procedure provides the default for the "package unknown" function.
# It is invoked when a package that's needed can't be found. It scans
# the auto_path directories looking for pkgIndex.tcl files and sources any
# such files that are found to setup the package database.
#
# Arguments:
# name - Name of desired package. Not used.
# version - Version of desired package. Not used.
# exact - Either "-exact" or omitted. Not used.
proc tclPkgUnknown {name version {exact {}}} {
global auto_path
if ![info exists auto_path] {
return
}
for {set i [expr [llength $auto_path] - 1]} {$i >= 0} {incr i -1} {
set dir [lindex $auto_path $i]
set file [file join $dir pkgIndex.tcl]
if [file readable $file] {
source $file
}
}
}