git-gui: Refactor into multiple files to save my sanity

I'm finding it difficult to work with a 6,000+ line Tcl script
and not go insane while looking for a particular block of code.
Since most of the program is organized into different units of
functionality and not all users will need all units immediately
on startup we can improve things by splitting procs out into
multiple files and let auto_load handle things for us.

This should help not only to better organize the source, but
it may also improve startup times for some users as the Tcl
parser does not need to read as much script before it can show
the UI.  In many cases the user can avoid reading at least half
of git-gui now.

Unfortunately we now need a library directory in our runtime
location.  This is currently assumed to be $(sharedir)/git-gui/lib
and its expected that the Makefile invoker will setup some sort of
reasonable sharedir value for us, or let us assume its going to be
$(gitexecdir)/../share.

We now also require a tclsh (in TCL_PATH) to just run the Makefile,
as we use tclsh to generate the tclIndex for our lib directory.  I'm
hoping this is not an unncessary burden on end-users who are building
from source.

I haven't really made any functionality changes here, this is just a
huge migration of code from one file to many smaller files.  All of
the new changes are to setup the library path and install the library
files.
Signed-off-by: NShawn O. Pearce <spearce@spearce.org>

.gitignore

@@ -2,3 +2,4 @@ GIT-VERSION-FILE
 GIT-GUI-VARS
 git-citool
 git-gui
+lib/tclIndex

Makefile

@@ -10,6 +10,7 @@ GIT-VERSION-FILE: .FORCE-GIT-VERSION-FILE
 SCRIPT_SH = git-gui.sh
 GITGUI_BUILT_INS = git-citool
 ALL_PROGRAMS = $(GITGUI_BUILT_INS) $(patsubst %.sh,%,$(SCRIPT_SH))
+ALL_LIBFILES = $(wildcard lib/*.tcl)
 
 ifndef SHELL_PATH
 	SHELL_PATH = /bin/sh
@@ -19,6 +20,10 @@ ifndef gitexecdir
 	gitexecdir := $(shell git --exec-path)
 endif
 
+ifndef sharedir
+	sharedir := $(dir $(gitexecdir))/share
+endif
+
 ifndef INSTALL
 	INSTALL = install
 endif
@@ -26,8 +31,10 @@ endif
 ifndef V
 	QUIET_GEN      = @echo '   ' GEN $@;
 	QUIET_BUILT_IN = @echo '   ' BUILTIN $@;
+	QUIET_INDEX    = @echo '   ' INDEX $(dir $@);
 endif
 
+TCL_PATH   ?= tclsh
 TCLTK_PATH ?= wish
 
 ifeq ($(findstring $(MAKEFLAGS),s),s)
@@ -40,11 +47,15 @@ gitexecdir_SQ = $(subst ','\'',$(gitexecdir))
 SHELL_PATH_SQ = $(subst ','\'',$(SHELL_PATH))
 TCLTK_PATH_SQ = $(subst ','\'',$(TCLTK_PATH))
 
+libdir   ?= $(sharedir)/git-gui/lib
+libdir_SQ = $(subst ','\'',$(libdir))
+
 $(patsubst %.sh,%,$(SCRIPT_SH)) : % : %.sh
 	$(QUIET_GEN)rm -f $@ $@+ && \
 	sed -e '1s|#!.*/sh|#!$(SHELL_PATH_SQ)|' \
 		-e 's|^exec wish "$$0"|exec $(subst |,'\|',$(TCLTK_PATH_SQ)) "$$0"|' \
 		-e 's/@@GITGUI_VERSION@@/$(GITGUI_VERSION)/g' \
+		-e 's|@@GITGUI_LIBDIR@@|$(libdir_SQ)|' \
 		$@.sh >$@+ && \
 	chmod +x $@+ && \
 	mv $@+ $@
@@ -52,12 +63,16 @@ $(patsubst %.sh,%,$(SCRIPT_SH)) : % : %.sh
 $(GITGUI_BUILT_INS): git-gui
 	$(QUIET_BUILT_IN)rm -f $@ && ln git-gui $@
 
+lib/tclIndex: $(ALL_LIBFILES)
+	$(QUIET_INDEX)echo auto_mkindex lib '*.tcl' | $(TCL_PATH)
+
 # These can record GITGUI_VERSION
 $(patsubst %.sh,%,$(SCRIPT_SH)): GIT-VERSION-FILE GIT-GUI-VARS
 
 TRACK_VARS = \
 	$(subst ','\'',SHELL_PATH='$(SHELL_PATH_SQ)') \
 	$(subst ','\'',TCLTK_PATH='$(TCLTK_PATH_SQ)') \
+	$(subst ','\'',libdir='$(libdir_SQ)') \
 #end TRACK_VARS
 
 GIT-GUI-VARS: .FORCE-GIT-GUI-VARS
@@ -67,19 +82,23 @@ GIT-GUI-VARS: .FORCE-GIT-GUI-VARS
 		echo 1>$@ "$$VARS"; \
 	fi
 
-all:: $(ALL_PROGRAMS)
+all:: $(ALL_PROGRAMS) lib/tclIndex
 
 install: all
 	$(INSTALL) -d -m755 '$(DESTDIR_SQ)$(gitexecdir_SQ)'
 	$(INSTALL) git-gui '$(DESTDIR_SQ)$(gitexecdir_SQ)'
 	$(foreach p,$(GITGUI_BUILT_INS), rm -f '$(DESTDIR_SQ)$(gitexecdir_SQ)/$p' && ln '$(DESTDIR_SQ)$(gitexecdir_SQ)/git-gui' '$(DESTDIR_SQ)$(gitexecdir_SQ)/$p' ;)
+	$(INSTALL) -d -m755 '$(DESTDIR_SQ)$(libdir_SQ)'
+	$(INSTALL) -m644 lib/tclIndex '$(DESTDIR_SQ)$(libdir_SQ)'
+	$(foreach p,$(ALL_LIBFILES), $(INSTALL) -m644 $p '$(DESTDIR_SQ)$(libdir_SQ)' ;)
 
 dist-version:
 	@mkdir -p $(TARDIR)
 	@echo $(GITGUI_VERSION) > $(TARDIR)/version
 
 clean::
-	rm -f $(ALL_PROGRAMS) GIT-VERSION-FILE GIT-GUI-VARS
+	rm -f $(ALL_PROGRAMS) lib/tclIndex
+	rm -f GIT-VERSION-FILE GIT-GUI-VARS
 
 .PHONY: all install dist-version clean
 .PHONY: .FORCE-GIT-VERSION-FILE

lib/blame.tcl

+# git-gui blame viewer
+# Copyright (C) 2006, 2007 Shawn Pearce
+
+proc show_blame {commit path} {
+	global next_browser_id blame_status blame_data
+
+	if {[winfo ismapped .]} {
+		set w .browser[incr next_browser_id]
+		set tl $w
+		toplevel $w
+	} else {
+		set w {}
+		set tl .
+	}
+	set blame_status($w) {Loading current file content...}
+
+	label $w.path -text "$commit:$path" \
+		-anchor w \
+		-justify left \
+		-borderwidth 1 \
+		-relief sunken \
+		-font font_uibold
+	pack $w.path -side top -fill x
+
+	frame $w.out
+	text $w.out.loaded_t \
+		-background white -borderwidth 0 \
+		-state disabled \
+		-wrap none \
+		-height 40 \
+		-width 1 \
+		-font font_diff
+	$w.out.loaded_t tag conf annotated -background grey
+
+	text $w.out.linenumber_t \
+		-background white -borderwidth 0 \
+		-state disabled \
+		-wrap none \
+		-height 40 \
+		-width 5 \
+		-font font_diff
+	$w.out.linenumber_t tag conf linenumber -justify right
+
+	text $w.out.file_t \
+		-background white -borderwidth 0 \
+		-state disabled \
+		-wrap none \
+		-height 40 \
+		-width 80 \
+		-xscrollcommand [list $w.out.sbx set] \
+		-font font_diff
+
+	scrollbar $w.out.sbx -orient h -command [list $w.out.file_t xview]
+	scrollbar $w.out.sby -orient v \
+		-command [list scrollbar2many [list \
+		$w.out.loaded_t \
+		$w.out.linenumber_t \
+		$w.out.file_t \
+		] yview]
+	grid \
+		$w.out.linenumber_t \
+		$w.out.loaded_t \
+		$w.out.file_t \
+		$w.out.sby \
+		-sticky nsew
+	grid conf $w.out.sbx -column 2 -sticky we
+	grid columnconfigure $w.out 2 -weight 1
+	grid rowconfigure $w.out 0 -weight 1
+	pack $w.out -fill both -expand 1
+
+	label $w.status -textvariable blame_status($w) \
+		-anchor w \
+		-justify left \
+		-borderwidth 1 \
+		-relief sunken
+	pack $w.status -side bottom -fill x
+
+	frame $w.cm
+	text $w.cm.t \
+		-background white -borderwidth 0 \
+		-state disabled \
+		-wrap none \
+		-height 10 \
+		-width 80 \
+		-xscrollcommand [list $w.cm.sbx set] \
+		-yscrollcommand [list $w.cm.sby set] \
+		-font font_diff
+	scrollbar $w.cm.sbx -orient h -command [list $w.cm.t xview]
+	scrollbar $w.cm.sby -orient v -command [list $w.cm.t yview]
+	pack $w.cm.sby -side right -fill y
+	pack $w.cm.sbx -side bottom -fill x
+	pack $w.cm.t -expand 1 -fill both
+	pack $w.cm -side bottom -fill x
+
+	menu $w.ctxm -tearoff 0
+	$w.ctxm add command -label "Copy Commit" \
+		-command "blame_copycommit $w \$cursorW @\$cursorX,\$cursorY"
+
+	foreach i [list \
+		$w.out.loaded_t \
+		$w.out.linenumber_t \
+		$w.out.file_t] {
+		$i tag conf in_sel \
+			-background [$i cget -foreground] \
+			-foreground [$i cget -background]
+		$i conf -yscrollcommand \
+			[list many2scrollbar [list \
+			$w.out.loaded_t \
+			$w.out.linenumber_t \
+			$w.out.file_t \
+			] yview $w.out.sby]
+		bind $i <Button-1> "
+			blame_click {$w} \\
+				$w.cm.t \\
+				$w.out.linenumber_t \\
+				$w.out.file_t \\
+				$i @%x,%y
+			focus $i
+		"
+		bind_button3 $i "
+			set cursorX %x
+			set cursorY %y
+			set cursorW %W
+			tk_popup $w.ctxm %X %Y
+		"
+	}
+
+	bind $w.cm.t <Button-1> "focus $w.cm.t"
+	bind $tl <Visibility> "focus $tl"
+	bind $tl <Destroy> "
+		array unset blame_status {$w}
+		array unset blame_data $w,*
+	"
+	wm title $tl "[appname] ([reponame]): File Viewer"
+
+	set blame_data($w,commit_count) 0
+	set blame_data($w,commit_list) {}
+	set blame_data($w,total_lines) 0
+	set blame_data($w,blame_lines) 0
+	set blame_data($w,highlight_commit) {}
+	set blame_data($w,highlight_line) -1
+
+	set cmd [list git cat-file blob "$commit:$path"]
+	set fd [open "| $cmd" r]
+	fconfigure $fd -blocking 0 -translation lf -encoding binary
+	fileevent $fd readable [list read_blame_catfile \
+		$fd $w $commit $path \
+		$w.cm.t $w.out.loaded_t $w.out.linenumber_t $w.out.file_t]
+}
+
+proc read_blame_catfile {fd w commit path w_cmit w_load w_line w_file} {
+	global blame_status blame_data
+
+	if {![winfo exists $w_file]} {
+		catch {close $fd}
+		return
+	}
+
+	set n $blame_data($w,total_lines)
+	$w_load conf -state normal
+	$w_line conf -state normal
+	$w_file conf -state normal
+	while {[gets $fd line] >= 0} {
+		regsub "\r\$" $line {} line
+		incr n
+		$w_load insert end "\n"
+		$w_line insert end "$n\n" linenumber
+		$w_file insert end "$line\n"
+	}
+	$w_load conf -state disabled
+	$w_line conf -state disabled
+	$w_file conf -state disabled
+	set blame_data($w,total_lines) $n
+
+	if {[eof $fd]} {
+		close $fd
+		blame_incremental_status $w
+		set cmd [list git blame -M -C --incremental]
+		lappend cmd $commit -- $path
+		set fd [open "| $cmd" r]
+		fconfigure $fd -blocking 0 -translation lf -encoding binary
+		fileevent $fd readable [list read_blame_incremental $fd $w \
+			$w_load $w_cmit $w_line $w_file]
+	}
+}
+
+proc read_blame_incremental {fd w w_load w_cmit w_line w_file} {
+	global blame_status blame_data
+
+	if {![winfo exists $w_file]} {
+		catch {close $fd}
+		return
+	}
+
+	while {[gets $fd line] >= 0} {
+		if {[regexp {^([a-z0-9]{40}) (\d+) (\d+) (\d+)$} $line line \
+			cmit original_line final_line line_count]} {
+			set blame_data($w,commit) $cmit
+			set blame_data($w,original_line) $original_line
+			set blame_data($w,final_line) $final_line
+			set blame_data($w,line_count) $line_count
+
+			if {[catch {set g $blame_data($w,$cmit,order)}]} {
+				$w_line tag conf g$cmit
+				$w_file tag conf g$cmit
+				$w_line tag raise in_sel
+				$w_file tag raise in_sel
+				$w_file tag raise sel
+				set blame_data($w,$cmit,order) $blame_data($w,commit_count)
+				incr blame_data($w,commit_count)
+				lappend blame_data($w,commit_list) $cmit
+			}
+		} elseif {[string match {filename *} $line]} {
+			set file [string range $line 9 end]
+			set n $blame_data($w,line_count)
+			set lno $blame_data($w,final_line)
+			set cmit $blame_data($w,commit)
+
+			while {$n > 0} {
+				if {[catch {set g g$blame_data($w,line$lno,commit)}]} {
+					$w_load tag add annotated $lno.0 "$lno.0 lineend + 1c"
+				} else {
+					$w_line tag remove g$g $lno.0 "$lno.0 lineend + 1c"
+					$w_file tag remove g$g $lno.0 "$lno.0 lineend + 1c"
+				}
+
+				set blame_data($w,line$lno,commit) $cmit
+				set blame_data($w,line$lno,file) $file
+				$w_line tag add g$cmit $lno.0 "$lno.0 lineend + 1c"
+				$w_file tag add g$cmit $lno.0 "$lno.0 lineend + 1c"
+
+				if {$blame_data($w,highlight_line) == -1} {
+					if {[lindex [$w_file yview] 0] == 0} {
+						$w_file see $lno.0
+						blame_showcommit $w $w_cmit $w_line $w_file $lno
+					}
+				} elseif {$blame_data($w,highlight_line) == $lno} {
+					blame_showcommit $w $w_cmit $w_line $w_file $lno
+				}
+
+				incr n -1
+				incr lno
+				incr blame_data($w,blame_lines)
+			}
+
+			set hc $blame_data($w,highlight_commit)
+			if {$hc ne {}
+				&& [expr {$blame_data($w,$hc,order) + 1}]
+					== $blame_data($w,$cmit,order)} {
+				blame_showcommit $w $w_cmit $w_line $w_file \
+					$blame_data($w,highlight_line)
+			}
+		} elseif {[regexp {^([a-z-]+) (.*)$} $line line header data]} {
+			set blame_data($w,$blame_data($w,commit),$header) $data
+		}
+	}
+
+	if {[eof $fd]} {
+		close $fd
+		set blame_status($w) {Annotation complete.}
+	} else {
+		blame_incremental_status $w
+	}
+}
+
+proc blame_incremental_status {w} {
+	global blame_status blame_data
+
+	set have  $blame_data($w,blame_lines)
+	set total $blame_data($w,total_lines)
+	set pdone 0
+	if {$total} {set pdone [expr {100 * $have / $total}]}
+
+	set blame_status($w) [format \
+		"Loading annotations... %i of %i lines annotated (%2i%%)" \
+		$have $total $pdone]
+}
+
+proc blame_click {w w_cmit w_line w_file cur_w pos} {
+	set lno [lindex [split [$cur_w index $pos] .] 0]
+	if {$lno eq {}} return
+
+	$w_line tag remove in_sel 0.0 end
+	$w_file tag remove in_sel 0.0 end
+	$w_line tag add in_sel $lno.0 "$lno.0 + 1 line"
+	$w_file tag add in_sel $lno.0 "$lno.0 + 1 line"
+
+	blame_showcommit $w $w_cmit $w_line $w_file $lno
+}
+
+set blame_colors {
+	#ff4040
+	#ff40ff
+	#4040ff
+}
+
+proc blame_showcommit {w w_cmit w_line w_file lno} {
+	global blame_colors blame_data repo_config
+
+	set cmit $blame_data($w,highlight_commit)
+	if {$cmit ne {}} {
+		set idx $blame_data($w,$cmit,order)
+		set i 0
+		foreach c $blame_colors {
+			set h [lindex $blame_data($w,commit_list) [expr {$idx - 1 + $i}]]
+			$w_line tag conf g$h -background white
+			$w_file tag conf g$h -background white
+			incr i
+		}
+	}
+
+	$w_cmit conf -state normal
+	$w_cmit delete 0.0 end
+	if {[catch {set cmit $blame_data($w,line$lno,commit)}]} {
+		set cmit {}
+		$w_cmit insert end "Loading annotation..."
+	} else {
+		set idx $blame_data($w,$cmit,order)
+		set i 0
+		foreach c $blame_colors {
+			set h [lindex $blame_data($w,commit_list) [expr {$idx - 1 + $i}]]
+			$w_line tag conf g$h -background $c
+			$w_file tag conf g$h -background $c
+			incr i
+		}
+
+		set author_name {}
+		set author_email {}
+		set author_time {}
+		catch {set author_name $blame_data($w,$cmit,author)}
+		catch {set author_email $blame_data($w,$cmit,author-mail)}
+		catch {set author_time [clock format $blame_data($w,$cmit,author-time)]}
+
+		set committer_name {}
+		set committer_email {}
+		set committer_time {}
+		catch {set committer_name $blame_data($w,$cmit,committer)}
+		catch {set committer_email $blame_data($w,$cmit,committer-mail)}
+		catch {set committer_time [clock format $blame_data($w,$cmit,committer-time)]}
+
+		if {[catch {set msg $blame_data($w,$cmit,message)}]} {
+			set msg {}
+			catch {
+				set fd [open "| git cat-file commit $cmit" r]
+				fconfigure $fd -encoding binary -translation lf
+				if {[catch {set enc $repo_config(i18n.commitencoding)}]} {
+					set enc utf-8
+				}
+				while {[gets $fd line] > 0} {
+					if {[string match {encoding *} $line]} {
+						set enc [string tolower [string range $line 9 end]]
+					}
+				}
+				set msg [encoding convertfrom $enc [read $fd]]
+				set msg [string trim $msg]
+				close $fd
+
+				set author_name [encoding convertfrom $enc $author_name]
+				set committer_name [encoding convertfrom $enc $committer_name]
+
+				set blame_data($w,$cmit,author) $author_name
+				set blame_data($w,$cmit,committer) $committer_name
+			}
+			set blame_data($w,$cmit,message) $msg
+		}
+
+		$w_cmit insert end "commit $cmit\n"
+		$w_cmit insert end "Author: $author_name $author_email $author_time\n"
+		$w_cmit insert end "Committer: $committer_name $committer_email $committer_time\n"
+		$w_cmit insert end "Original File: [escape_path $blame_data($w,line$lno,file)]\n"
+		$w_cmit insert end "\n"
+		$w_cmit insert end $msg
+	}
+	$w_cmit conf -state disabled
+
+	set blame_data($w,highlight_line) $lno
+	set blame_data($w,highlight_commit) $cmit
+}
+
+proc blame_copycommit {w i pos} {
+	global blame_data
+	set lno [lindex [split [$i index $pos] .] 0]
+	if {![catch {set commit $blame_data($w,line$lno,commit)}]} {
+		clipboard clear
+		clipboard append \
+			-format STRING \
+			-type STRING \
+			-- $commit
+	}
+}

lib/browser.tcl

+# git-gui tree browser
+# Copyright (C) 2006, 2007 Shawn Pearce
+
+set next_browser_id 0
+
+proc new_browser {commit} {
+	global next_browser_id cursor_ptr M1B
+	global browser_commit browser_status browser_stack browser_path browser_busy
+
+	if {[winfo ismapped .]} {
+		set w .browser[incr next_browser_id]
+		set tl $w
+		toplevel $w
+	} else {
+		set w {}
+		set tl .
+	}
+	set w_list $w.list.l
+	set browser_commit($w_list) $commit
+	set browser_status($w_list) {Starting...}
+	set browser_stack($w_list) {}
+	set browser_path($w_list) $browser_commit($w_list):
+	set browser_busy($w_list) 1
+
+	label $w.path -textvariable browser_path($w_list) \
+		-anchor w \
+		-justify left \
+		-borderwidth 1 \
+		-relief sunken \
+		-font font_uibold
+	pack $w.path -anchor w -side top -fill x
+
+	frame $w.list
+	text $w_list -background white -borderwidth 0 \
+		-cursor $cursor_ptr \
+		-state disabled \
+		-wrap none \
+		-height 20 \
+		-width 70 \
+		-xscrollcommand [list $w.list.sbx set] \
+		-yscrollcommand [list $w.list.sby set]
+	$w_list tag conf in_sel \
+		-background [$w_list cget -foreground] \
+		-foreground [$w_list cget -background]
+	scrollbar $w.list.sbx -orient h -command [list $w_list xview]
+	scrollbar $w.list.sby -orient v -command [list $w_list yview]
+	pack $w.list.sbx -side bottom -fill x
+	pack $w.list.sby -side right -fill y
+	pack $w_list -side left -fill both -expand 1
+	pack $w.list -side top -fill both -expand 1
+
+	label $w.status -textvariable browser_status($w_list) \
+		-anchor w \
+		-justify left \
+		-borderwidth 1 \
+		-relief sunken
+	pack $w.status -anchor w -side bottom -fill x
+
+	bind $w_list <Button-1>        "browser_click 0 $w_list @%x,%y;break"
+	bind $w_list <Double-Button-1> "browser_click 1 $w_list @%x,%y;break"
+	bind $w_list <$M1B-Up>         "browser_parent $w_list;break"
+	bind $w_list <$M1B-Left>       "browser_parent $w_list;break"
+	bind $w_list <Up>              "browser_move -1 $w_list;break"
+	bind $w_list <Down>            "browser_move 1 $w_list;break"
+	bind $w_list <$M1B-Right>      "browser_enter $w_list;break"
+	bind $w_list <Return>          "browser_enter $w_list;break"
+	bind $w_list <Prior>           "browser_page -1 $w_list;break"
+	bind $w_list <Next>            "browser_page 1 $w_list;break"
+	bind $w_list <Left>            break
+	bind $w_list <Right>           break
+
+	bind $tl <Visibility> "focus $w"
+	bind $tl <Destroy> "
+		array unset browser_buffer $w_list
+		array unset browser_files $w_list
+		array unset browser_status $w_list
+		array unset browser_stack $w_list
+		array unset browser_path $w_list
+		array unset browser_commit $w_list
+		array unset browser_busy $w_list
+	"
+	wm title $tl "[appname] ([reponame]): File Browser"
+	ls_tree $w_list $browser_commit($w_list) {}
+}
+
+proc browser_move {dir w} {
+	global browser_files browser_busy
+
+	if {$browser_busy($w)} return
+	set lno [lindex [split [$w index in_sel.first] .] 0]
+	incr lno $dir
+	if {[lindex $browser_files($w) [expr {$lno - 1}]] ne {}} {
+		$w tag remove in_sel 0.0 end
+		$w tag add in_sel $lno.0 [expr {$lno + 1}].0
+		$w see $lno.0
+	}
+}
+
+proc browser_page {dir w} {
+	global browser_files browser_busy
+
+	if {$browser_busy($w)} return
+	$w yview scroll $dir pages
+	set lno [expr {int(
+		  [lindex [$w yview] 0]
+		* [llength $browser_files($w)]
+		+ 1)}]
+	if {[lindex $browser_files($w) [expr {$lno - 1}]] ne {}} {
+		$w tag remove in_sel 0.0 end
+		$w tag add in_sel $lno.0 [expr {$lno + 1}].0
+		$w see $lno.0
+	}
+}
+
+proc browser_parent {w} {
+	global browser_files browser_status browser_path
+	global browser_stack browser_busy
+
+	if {$browser_busy($w)} return
+	set info [lindex $browser_files($w) 0]
+	if {[lindex $info 0] eq {parent}} {
+		set parent [lindex $browser_stack($w) end-1]
+		set browser_stack($w) [lrange $browser_stack($w) 0 end-2]
+		if {$browser_stack($w) eq {}} {
+			regsub {:.*$} $browser_path($w) {:} browser_path($w)
+		} else {
+			regsub {/[^/]+$} $browser_path($w) {} browser_path($w)
+		}
+		set browser_status($w) "Loading $browser_path($w)..."
+		ls_tree $w [lindex $parent 0] [lindex $parent 1]
+	}
+}
+
+proc browser_enter {w} {
+	global browser_files browser_status browser_path
+	global browser_commit browser_stack browser_busy
+
+	if {$browser_busy($w)} return
+	set lno [lindex [split [$w index in_sel.first] .] 0]
+	set info [lindex $browser_files($w) [expr {$lno - 1}]]
+	if {$info ne {}} {
+		switch -- [lindex $info 0] {
+		parent {
+			browser_parent $w
+		}
+		tree {
+			set name [lindex $info 2]
+			set escn [escape_path $name]
+			set browser_status($w) "Loading $escn..."
+			append browser_path($w) $escn
+			ls_tree $w [lindex $info 1] $name
+		}
+		blob {
+			set name [lindex $info 2]
+			set p {}
+			foreach n $browser_stack($w) {
+				append p [lindex $n 1]
+			}
+			append p $name
+			show_blame $browser_commit($w) $p
+		}
+		}
+	}
+}
+
+proc browser_click {was_double_click w pos} {
+	global browser_files browser_busy
+
+	if {$browser_busy($w)} return
+	set lno [lindex [split [$w index $pos] .] 0]
+	focus $w
+
+	if {[lindex $browser_files($w) [expr {$lno - 1}]] ne {}} {
+		$w tag remove in_sel 0.0 end
+		$w tag add in_sel $lno.0 [expr {$lno + 1}].0
+		if {$was_double_click} {
+			browser_enter $w
+		}
+	}
+}
+
+proc ls_tree {w tree_id name} {
+	global browser_buffer browser_files browser_stack browser_busy
+
+	set browser_buffer($w) {}
+	set browser_files($w) {}
+	set browser_busy($w) 1
+
+	$w conf -state normal
+	$w tag remove in_sel 0.0 end
+	$w delete 0.0 end
+	if {$browser_stack($w) ne {}} {
+		$w image create end \
+			-align center -padx 5 -pady 1 \
+			-name icon0 \
+			-image file_uplevel
+		$w insert end {[Up To Parent]}
+		lappend browser_files($w) parent
+	}
+	lappend browser_stack($w) [list $tree_id $name]
+	$w conf -state disabled
+
+	set cmd [list git ls-tree -z $tree_id]
+	set fd [open "| $cmd" r]
+	fconfigure $fd -blocking 0 -translation binary -encoding binary
+	fileevent $fd readable [list read_ls_tree $fd $w]
+}
+
+proc read_ls_tree {fd w} {
+	global browser_buffer browser_files browser_status browser_busy
+
+	if {![winfo exists $w]} {
+		catch {close $fd}
+		return
+	}
+
+	append browser_buffer($w) [read $fd]
+	set pck [split $browser_buffer($w) "\0"]
+	set browser_buffer($w) [lindex $pck end]
+
+	set n [llength $browser_files($w)]
+	$w conf -state normal
+	foreach p [lrange $pck 0 end-1] {
+		set info [split $p "\t"]
+		set path [lindex $info 1]
+		set info [split [lindex $info 0] { }]
+		set type [lindex $info 1]
+		set object [lindex $info 2]
+
+		switch -- $type {
+		blob {
+			set image file_mod
+		}
+		tree {
+			set image file_dir
+			append path /
+		}
+		default {
+			set image file_question
+		}
+		}
+
+		if {$n > 0} {$w insert end "\n"}
+		$w image create end \
+			-align center -padx 5 -pady 1 \
+			-name icon[incr n] \
+			-image $image
+		$w insert end [escape_path $path]
+		lappend browser_files($w) [list $type $object $path]
+	}
+	$w conf -state disabled
+
+	if {[eof $fd]} {
+		close $fd
+		set browser_status($w) Ready.
+		set browser_busy($w) 0
+		array unset browser_buffer $w
+		if {$n > 0} {
+			$w tag add in_sel 1.0 2.0
+			focus -force $w
+		}
+	}
+}