X-Git-Url: https://git.octo.it/?a=blobdiff_plain;f=gitk;h=b38d7cd0ed4fff6b76d591f36e96fef0cc64669b;hb=94a2eede68f2d3cacef489044f5b822f45f2a10d;hp=2db187c017fab2358eaa4a782d0f599437c90d0e;hpb=e2ed4324b0b99fd3cb93bd14b6e1599c6fcbfe23;p=git.git

diff --git a/gitk b/gitk
index 2db187c0..b38d7cd0 100755
--- a/gitk
+++ b/gitk
@@ -7,17 +7,22 @@ exec wish "$0" -- "${1+$@}"
 # and distributed under the terms of the GNU General Public Licence,
 # either version 2, or (at your option) any later version.
 
+proc gitdir {} {
+    global env
+    if {[info exists env(GIT_DIR)]} {
+	return $env(GIT_DIR)
+    } else {
+	return ".git"
+    }
+}
+
 proc getcommits {rargs} {
     global commits commfd phase canv mainfont env
     global startmsecs nextupdate
     global ctext maincursor textcursor leftover
 
     # check that we can find a .git directory somewhere...
-    if {[info exists env(GIT_DIR)]} {
-	set gitdir $env(GIT_DIR)
-    } else {
-	set gitdir ".git"
-    }
+    set gitdir [gitdir]
     if {![file isdirectory $gitdir]} {
 	error_popup "Cannot find the git directory \"$gitdir\"."
 	exit 1
@@ -37,7 +42,7 @@ proc getcommits {rargs} {
 	set parsed_args $rargs
     }
     if [catch {
-	set commfd [open "|git-rev-list --header --merge-order $parsed_args" r]
+	set commfd [open "|git-rev-list --header --topo-order $parsed_args" r]
     } err] {
 	puts stderr "Error executing git-rev-list: $err"
 	exit 1
@@ -49,7 +54,7 @@ proc getcommits {rargs} {
     $canv create text 3 3 -anchor nw -text "Reading commits..." \
 	-font $mainfont -tags textitems
     . config -cursor watch
-    $ctext config -cursor watch
+    settextcursor watch
 }
 
 proc getcommitlines {commfd}  {
@@ -60,7 +65,7 @@ proc getcommitlines {commfd}  {
     set stuff [read $commfd]
     if {$stuff == {}} {
 	if {![eof $commfd]} return
-	# this works around what is apparently a bug in Tcl...
+	# set it blocking so we wait for the process to terminate
 	fconfigure $commfd -blocking 1
 	if {![catch {close $commfd} err]} {
 	    after idle finishcommits
@@ -212,7 +217,7 @@ proc parsecommit {id contents listed} {
 
 proc readrefs {} {
     global tagids idtags headids idheads
-    set tags [glob -nocomplain -types f .git/refs/tags/*]
+    set tags [glob -nocomplain -types f [gitdir]/refs/tags/*]
     foreach f $tags {
 	catch {
 	    set fd [open $f r]
@@ -241,7 +246,7 @@ proc readrefs {} {
 	    close $fd
 	}
     }
-    set heads [glob -nocomplain -types f .git/refs/heads/*]
+    set heads [glob -nocomplain -types f [gitdir]/refs/heads/*]
     foreach f $heads {
 	catch {
 	    set fd [open $f r]
@@ -272,8 +277,8 @@ proc makewindow {} {
     global canv canv2 canv3 linespc charspc ctext cflist textfont
     global findtype findtypemenu findloc findstring fstring geometry
     global entries sha1entry sha1string sha1but
-    global maincursor textcursor
-    global rowctxmenu
+    global maincursor textcursor curtextcursor
+    global rowctxmenu gaudydiff mergemax
 
     menu .bar
     .bar add cascade -label "File" -menu .bar.file
@@ -334,6 +339,30 @@ proc makewindow {} {
     entry $sha1entry -width 40 -font $textfont -textvariable sha1string
     trace add variable sha1string write sha1change
     pack $sha1entry -side left -pady 2
+
+    image create bitmap bm-left -data {
+	#define left_width 16
+	#define left_height 16
+	static unsigned char left_bits[] = {
+	0x00, 0x00, 0xc0, 0x01, 0xe0, 0x00, 0x70, 0x00, 0x38, 0x00, 0x1c, 0x00,
+	0x0e, 0x00, 0xff, 0x7f, 0xff, 0x7f, 0xff, 0x7f, 0x0e, 0x00, 0x1c, 0x00,
+	0x38, 0x00, 0x70, 0x00, 0xe0, 0x00, 0xc0, 0x01};
+    }
+    image create bitmap bm-right -data {
+	#define right_width 16
+	#define right_height 16
+	static unsigned char right_bits[] = {
+	0x00, 0x00, 0xc0, 0x01, 0x80, 0x03, 0x00, 0x07, 0x00, 0x0e, 0x00, 0x1c,
+	0x00, 0x38, 0xff, 0x7f, 0xff, 0x7f, 0xff, 0x7f, 0x00, 0x38, 0x00, 0x1c,
+	0x00, 0x0e, 0x00, 0x07, 0x80, 0x03, 0xc0, 0x01};
+    }
+    button .ctop.top.bar.leftbut -image bm-left -command goback \
+	-state disabled -width 26
+    pack .ctop.top.bar.leftbut -side left -fill y
+    button .ctop.top.bar.rightbut -image bm-right -command goforw \
+	-state disabled -width 26
+    pack .ctop.top.bar.rightbut -side left -fill y
+
     button .ctop.top.bar.findbut -text "Find" -command dofind
     pack .ctop.top.bar.findbut -side left
     set findstring {}
@@ -364,11 +393,26 @@ proc makewindow {} {
     pack $ctext -side left -fill both -expand 1
     .ctop.cdet add .ctop.cdet.left
 
-    $ctext tag conf filesep -font [concat $textfont bold]
-    $ctext tag conf hunksep -back blue -fore white
-    $ctext tag conf d0 -back "#ff8080"
-    $ctext tag conf d1 -back green
-    $ctext tag conf found -back yellow
+    $ctext tag conf filesep -font [concat $textfont bold] -back "#aaaaaa"
+    if {$gaudydiff} {
+	$ctext tag conf hunksep -back blue -fore white
+	$ctext tag conf d0 -back "#ff8080"
+	$ctext tag conf d1 -back green
+    } else {
+	$ctext tag conf hunksep -fore blue
+	$ctext tag conf d0 -fore red
+	$ctext tag conf d1 -fore "#00a000"
+	$ctext tag conf m0 -fore red
+	$ctext tag conf m1 -fore blue
+	$ctext tag conf m2 -fore green
+	$ctext tag conf m3 -fore purple
+	$ctext tag conf m4 -fore brown
+	$ctext tag conf mmax -fore darkgrey
+	set mergemax 5
+	$ctext tag conf mresult -font [concat $textfont bold]
+	$ctext tag conf msep -font [concat $textfont bold]
+	$ctext tag conf found -back yellow
+    }
 
     frame .ctop.cdet.right
     set cflist .ctop.cdet.right.cfiles
@@ -421,6 +465,7 @@ proc makewindow {} {
 
     set maincursor [. cget -cursor]
     set textcursor [$ctext cget -cursor]
+    set curtextcursor $textcursor
 
     set rowctxmenu .rowctxmenu
     menu $rowctxmenu -tearoff 0
@@ -460,13 +505,17 @@ proc click {w} {
 
 proc savestuff {w} {
     global canv canv2 canv3 ctext cflist mainfont textfont
-    global stuffsaved
+    global stuffsaved findmergefiles gaudydiff maxgraphpct
+
     if {$stuffsaved} return
     if {![winfo viewable .]} return
     catch {
 	set f [open "~/.gitk-new" w]
-	puts $f "set mainfont {$mainfont}"
-	puts $f "set textfont {$textfont}"
+	puts $f [list set mainfont $mainfont]
+	puts $f [list set textfont $textfont]
+	puts $f [list set findmergefiles $findmergefiles]
+	puts $f [list set gaudydiff $gaudydiff]
+	puts $f [list set maxgraphpct $maxgraphpct]
 	puts $f "set geometry(width) [winfo width .ctop]"
 	puts $f "set geometry(height) [winfo height .ctop]"
 	puts $f "set geometry(canv1) [expr [winfo width $canv]-2]"
@@ -671,7 +720,7 @@ proc bindline {t id} {
 
 proc drawcommitline {level} {
     global parents children nparents nchildren todo
-    global canv canv2 canv3 mainfont namefont canvx0 canvy linespc
+    global canv canv2 canv3 mainfont namefont canvy linespc
     global lineid linehtag linentag linedtag commitinfo
     global colormap numcommits currentparents dupparents
     global oldlevel oldnlines oldtodo
@@ -705,7 +754,7 @@ proc drawcommitline {level} {
 	    }
 	}
     }
-    set x [expr $canvx0 + $level * $linespc]
+    set x [xcoord $level $level $lineno]
     set y1 $canvy
     set canvy [expr $canvy + $linespc]
     allcanvs conf -scrollregion \
@@ -733,7 +782,7 @@ proc drawcommitline {level} {
 	       -fill $ofill -outline black -width 1]
     $canv raise $t
     $canv bind $t <1> {selcanvline {} %x %y}
-    set xt [expr $canvx0 + [llength $todo] * $linespc]
+    set xt [xcoord [llength $todo] $level $lineno]
     if {[llength $currentparents] > 2} {
 	set xt [expr {$xt + ([llength $currentparents] - 2) * $linespc}]
     }
@@ -809,8 +858,8 @@ proc drawtags {id x xt y1} {
 proc updatetodo {level noshortcut} {
     global currentparents ncleft todo
     global mainline oldlevel oldtodo oldnlines
-    global canvx0 canvy linespc mainline
-    global commitinfo
+    global canvy linespc mainline
+    global commitinfo lineno xspc1
 
     set oldlevel $level
     set oldtodo $todo
@@ -819,10 +868,11 @@ proc updatetodo {level noshortcut} {
 	set p [lindex $currentparents 0]
 	if {$ncleft($p) == 1 && [lsearch -exact $todo $p] < 0} {
 	    set ncleft($p) 0
-	    set x [expr $canvx0 + $level * $linespc]
+	    set x [xcoord $level $level $lineno]
 	    set y [expr $canvy - $linespc]
 	    set mainline($p) [list $x $y]
 	    set todo [lreplace $todo $level $level $p]
+	    set xspc1([expr {$lineno + 1}]) $xspc1($lineno)
 	    return 0
 	}
     }
@@ -868,28 +918,54 @@ proc notecrossings {id lo hi corner} {
     }
 }
 
-proc drawslants {} {
-    global canv mainline sidelines canvx0 canvy linespc
-    global oldlevel oldtodo todo currentparents dupparents
-    global lthickness linespc canvy colormap
+proc xcoord {i level ln} {
+    global canvx0 xspc1 xspc2
 
+    set x [expr {$canvx0 + $i * $xspc1($ln)}]
+    if {$i > 0 && $i == $level} {
+	set x [expr {$x + 0.5 * ($xspc2 - $xspc1($ln))}]
+    } elseif {$i > $level} {
+	set x [expr {$x + $xspc2 - $xspc1($ln)}]
+    }
+    return $x
+}
+
+proc drawslants {level} {
+    global canv mainline sidelines canvx0 canvy xspc1 xspc2 lthickness
+    global oldlevel oldtodo todo currentparents dupparents
+    global lthickness linespc canvy colormap lineno geometry
+    global maxgraphpct
+
+    # decide on the line spacing for the next line
+    set lj [expr {$lineno + 1}]
+    set maxw [expr {$maxgraphpct * $geometry(canv1) / 100}]
+    set n [llength $todo]
+    if {$n <= 1 || $canvx0 + $n * $xspc2 <= $maxw} {
+	set xspc1($lj) $xspc2
+    } else {
+	set xspc1($lj) [expr {($maxw - $canvx0 - $xspc2) / ($n - 1)}]
+	if {$xspc1($lj) < $lthickness} {
+	    set xspc1($lj) $lthickness
+	}
+    }
+    
     set y1 [expr $canvy - $linespc]
     set y2 $canvy
     set i -1
     foreach id $oldtodo {
 	incr i
 	if {$id == {}} continue
-	set xi [expr {$canvx0 + $i * $linespc}]
+	set xi [xcoord $i $oldlevel $lineno]
 	if {$i == $oldlevel} {
 	    foreach p $currentparents {
 		set j [lsearch -exact $todo $p]
 		set coords [list $xi $y1]
-		set xj [expr {$canvx0 + $j * $linespc}]
-		if {$j < $i - 1} {
-		    lappend coords [expr $xj + $linespc] $y1
+		set xj [xcoord $j $level $lj]
+		if {$xj < $xi - $linespc} {
+		    lappend coords [expr {$xj + $linespc}] $y1
 		    notecrossings $p $j $i [expr {$j + 1}]
-		} elseif {$j > $i + 1} {
-		    lappend coords [expr $xj - $linespc] $y1
+		} elseif {$xj > $xi + $linespc} {
+		    lappend coords [expr {$xj - $linespc}] $y1
 		    notecrossings $p $i $j [expr {$j - 1}]
 		}
 		if {[lsearch -exact $dupparents $p] >= 0} {
@@ -901,28 +977,48 @@ proc drawslants {} {
 		    }
 		} else {
 		    # normal case, no parent duplicated
+		    set yb $y2
+		    set dx [expr {abs($xi - $xj)}]
+		    if {0 && $dx < $linespc} {
+			set yb [expr {$y1 + $dx}]
+		    }
 		    if {![info exists mainline($p)]} {
-			if {$i != $j} {
-			    lappend coords $xj $y2
+			if {$xi != $xj} {
+			    lappend coords $xj $yb
 			}
 			set mainline($p) $coords
 		    } else {
-			lappend coords $xj $y2
+			lappend coords $xj $yb
+			if {$yb < $y2} {
+			    lappend coords $xj $y2
+			}
 			lappend sidelines($p) [list $coords 1]
 		    }
 		}
 	    }
-	} elseif {[lindex $todo $i] != $id} {
-	    set j [lsearch -exact $todo $id]
-	    set xj [expr {$canvx0 + $j * $linespc}]
-	    lappend mainline($id) $xi $y1 $xj $y2
+	} else {
+	    set j $i
+	    if {[lindex $todo $i] != $id} {
+		set j [lsearch -exact $todo $id]
+	    }
+	    if {$j != $i || $xspc1($lineno) != $xspc1($lj)
+		|| ($oldlevel <= $i && $i <= $level)
+		|| ($level <= $i && $i <= $oldlevel)} {
+		set xj [xcoord $j $level $lj]
+		set dx [expr {abs($xi - $xj)}]
+		set yb $y2
+		if {0 && $dx < $linespc} {
+		    set yb [expr {$y1 + $dx}]
+		}
+		lappend mainline($id) $xi $y1 $xj $yb
+	    }
 	}
     }
 }
 
 proc decidenext {{noread 0}} {
     global parents children nchildren ncleft todo
-    global canv canv2 canv3 mainfont namefont canvx0 canvy linespc
+    global canv canv2 canv3 mainfont namefont canvy linespc
     global datemode cdate
     global commitinfo
     global currentparents oldlevel oldnlines oldtodo
@@ -1013,7 +1109,7 @@ proc drawcommit {id} {
 	    return
 	}
 	while 1 {
-	    drawslants
+	    drawslants $level
 	    drawcommitline $level
 	    if {[updatetodo $level $datemode]} {
 		set level [decidenext 1]
@@ -1042,12 +1138,23 @@ proc finishcommits {} {
 	    -font $mainfont -tags textitems
 	set phase {}
     } else {
-	drawslants
 	set level [decidenext]
+	drawslants $level
 	drawrest $level [llength $startcommits]
     }
     . config -cursor $maincursor
-    $ctext config -cursor $textcursor
+    settextcursor $textcursor
+}
+
+# Don't change the text pane cursor if it is currently the hand cursor,
+# showing that we are over a sha1 ID link.
+proc settextcursor {c} {
+    global ctext curtextcursor
+
+    if {[$ctext cget -cursor] == $curtextcursor} {
+	$ctext config -cursor $c
+    }
+    set curtextcursor $c
 }
 
 proc drawgraph {} {
@@ -1091,7 +1198,7 @@ proc drawrest {level startix} {
 	    if {$hard} {
 		set level [decidenext]
 		if {$level < 0} break
-		drawslants
+		drawslants $level
 	    }
 	    if {[clock clicks -milliseconds] >= $nextupdate} {
 		update
@@ -1104,7 +1211,7 @@ proc drawrest {level startix} {
     #puts "overall $drawmsecs ms for $numcommits commits"
     if {$redisplaying} {
 	if {$stopped == 0 && [info exists selectedline]} {
-	    selectline $selectedline
+	    selectline $selectedline 0
 	}
 	if {$stopped == 1} {
 	    set stopped 0
@@ -1203,7 +1310,7 @@ proc dofind {} {
 
 proc findselectline {l} {
     global findloc commentend ctext
-    selectline $l
+    selectline $l 1
     if {$findloc == "All fields" || $findloc == "Comments"} {
 	# highlight the matches in the comments
 	set f [$ctext get 1.0 $commentend]
@@ -1282,7 +1389,7 @@ proc stopfindproc {{done 0}} {
 	unset findinprogress
 	if {$phase != "incrdraw"} {
 	    . config -cursor $maincursor
-	    $ctext config -cursor $textcursor
+	    settextcursor $textcursor
 	}
     }
 }
@@ -1325,7 +1432,7 @@ proc findpatches {} {
     fileevent $f readable readfindproc
     set finddidsel 0
     . config -cursor watch
-    $ctext config -cursor watch
+    settextcursor watch
     set findinprogress 1
 }
 
@@ -1430,7 +1537,7 @@ proc findfiles {} {
     set id $lineid($l)
     set p [lindex $parents($id) 0]
     . config -cursor watch
-    $ctext config -cursor watch
+    settextcursor watch
     set findinprogress 1
     findcont [list $id $p]
     update
@@ -1496,7 +1603,7 @@ proc donefilediff {} {
 }
 
 proc findcont {ids} {
-    global findids treediffs parents nparents treepending
+    global findids treediffs parents nparents
     global ffileline findstartline finddidsel
     global lineid numcommits matchinglines findinprogress
     global findmergefiles
@@ -1594,15 +1701,17 @@ proc selcanvline {w x y} {
 	if {![info exists rowtextx($l)] || $x < $rowtextx($l)} return
     }
     unmarkmatches
-    selectline $l
+    selectline $l 1
 }
 
-proc selectline {l} {
+proc selectline {l isnew} {
     global canv canv2 canv3 ctext commitinfo selectedline
     global lineid linehtag linentag linedtag
     global canvy0 linespc parents nparents
     global cflist currentid sha1entry
-    global commentend seenfile idtags
+    global commentend idtags idline
+    global history historyindex
+
     $canv delete hover
     if {![info exists lineid($l)] || ![info exists linehtag($l)]} return
     $canv delete secsel
@@ -1651,6 +1760,22 @@ proc selectline {l} {
 	}
 	allcanvs yview moveto [expr $newtop * 1.0 / $ymax]
     }
+
+    if {$isnew && (![info exists selectedline] || $selectedline != $l)} {
+	if {$historyindex < [llength $history]} {
+	    set history [lreplace $history $historyindex end $l]
+	} else {
+	    lappend history $l
+	}
+	incr historyindex
+	if {$historyindex > 1} {
+	    .ctop.top.bar.leftbut conf -state normal
+	} else {
+	    .ctop.top.bar.leftbut conf -state disabled
+	}
+	.ctop.top.bar.rightbut conf -state disabled
+    }
+
     set selectedline $l
 
     set id $lineid($l)
@@ -1675,8 +1800,29 @@ proc selectline {l} {
 	$ctext insert end "\n"
     }
     $ctext insert end "\n"
-    $ctext insert end [lindex $info 5]
+    set commentstart [$ctext index "end - 1c"]
+    set comment [lindex $info 5]
+    $ctext insert end $comment
     $ctext insert end "\n"
+
+    # make anything that looks like a SHA1 ID be a clickable link
+    set links [regexp -indices -all -inline {[0-9a-f]{40}} $comment]
+    set i 0
+    foreach l $links {
+	set s [lindex $l 0]
+	set e [lindex $l 1]
+	set linkid [string range $comment $s $e]
+	if {![info exists idline($linkid)]} continue
+	incr e
+	$ctext tag add link "$commentstart + $s c" "$commentstart + $e c"
+	$ctext tag add link$i "$commentstart + $s c" "$commentstart + $e c"
+	$ctext tag bind link$i <1> [list selectline $idline($linkid) 1]
+	incr i
+    }
+    $ctext tag conf link -foreground blue -underline 1
+    $ctext tag bind link <Enter> { %W configure -cursor hand2 }
+    $ctext tag bind link <Leave> { %W configure -cursor $curtextcursor }
+
     $ctext tag delete Comments
     $ctext tag remove found 1.0 end
     $ctext conf -state disabled
@@ -1684,29 +1830,580 @@ proc selectline {l} {
 
     $cflist delete 0 end
     $cflist insert end "Comments"
-    startdiff $id $parents($id)
+    if {$nparents($id) == 1} {
+	startdiff [concat $id $parents($id)]
+    } elseif {$nparents($id) > 1} {
+	mergediff $id
+    }
 }
 
-proc startdiff {id vs} {
-    global diffpending diffpindex
-    global diffindex difffilestart seenfile
-    global curdifftag curtagstart
+proc selnextline {dir} {
+    global selectedline
+    if {![info exists selectedline]} return
+    set l [expr $selectedline + $dir]
+    unmarkmatches
+    selectline $l 1
+}
 
-    set diffpending $vs
-    set diffpindex 0
-    catch {unset seenfile}
-    set diffindex 0
-    catch {unset difffilestart}
-    set curdifftag Comments
-    set curtagstart 0.0
-    contdiff [list $id [lindex $vs 0]]
+proc goback {} {
+    global history historyindex
+
+    if {$historyindex > 1} {
+	incr historyindex -1
+	selectline [lindex $history [expr {$historyindex - 1}]] 0
+	.ctop.top.bar.rightbut conf -state normal
+    }
+    if {$historyindex <= 1} {
+	.ctop.top.bar.leftbut conf -state disabled
+    }
+}
+
+proc goforw {} {
+    global history historyindex
+
+    if {$historyindex < [llength $history]} {
+	set l [lindex $history $historyindex]
+	incr historyindex
+	selectline $l 0
+	.ctop.top.bar.leftbut conf -state normal
+    }
+    if {$historyindex >= [llength $history]} {
+	.ctop.top.bar.rightbut conf -state disabled
+    }
+}
+
+proc mergediff {id} {
+    global parents diffmergeid diffmergegca mergefilelist diffpindex
+
+    set diffmergeid $id
+    set diffpindex -1
+    set diffmergegca [findgca $parents($id)]
+    if {[info exists mergefilelist($id)]} {
+	if {$mergefilelist($id) ne {}} {
+	    showmergediff
+	}
+    } else {
+	contmergediff {}
+    }
 }
 
-proc contdiff {ids} {
-    global treediffs diffids treepending
+proc findgca {ids} {
+    set gca {}
+    foreach id $ids {
+	if {$gca eq {}} {
+	    set gca $id
+	} else {
+	    if {[catch {
+		set gca [exec git-merge-base $gca $id]
+	    } err]} {
+		return {}
+	    }
+	}
+    }
+    return $gca
+}
+
+proc contmergediff {ids} {
+    global diffmergeid diffpindex parents nparents diffmergegca
+    global treediffs mergefilelist diffids treepending
+
+    # diff the child against each of the parents, and diff
+    # each of the parents against the GCA.
+    while 1 {
+	if {[lindex $ids 0] == $diffmergeid && $diffmergegca ne {}} {
+	    set ids [list [lindex $ids 1] $diffmergegca]
+	} else {
+	    if {[incr diffpindex] >= $nparents($diffmergeid)} break
+	    set p [lindex $parents($diffmergeid) $diffpindex]
+	    set ids [list $diffmergeid $p]
+	}
+	if {![info exists treediffs($ids)]} {
+	    set diffids $ids
+	    if {![info exists treepending]} {
+		gettreediffs $ids
+	    }
+	    return
+	}
+    }
+
+    # If a file in some parent is different from the child and also
+    # different from the GCA, then it's interesting.
+    # If we don't have a GCA, then a file is interesting if it is
+    # different from the child in all the parents.
+    if {$diffmergegca ne {}} {
+	set files {}
+	foreach p $parents($diffmergeid) {
+	    set gcadiffs $treediffs([list $p $diffmergegca])
+	    foreach f $treediffs([list $diffmergeid $p]) {
+		if {[lsearch -exact $files $f] < 0
+		    && [lsearch -exact $gcadiffs $f] >= 0} {
+		    lappend files $f
+		}
+	    }
+	}
+	set files [lsort $files]
+    } else {
+	set p [lindex $parents($diffmergeid) 0]
+	set files $treediffs([list $diffmergeid $p])
+	for {set i 1} {$i < $nparents($diffmergeid) && $files ne {}} {incr i} {
+	    set p [lindex $parents($diffmergeid) $i]
+	    set df $treediffs([list $diffmergeid $p])
+	    set nf {}
+	    foreach f $files {
+		if {[lsearch -exact $df $f] >= 0} {
+		    lappend nf $f
+		}
+	    }
+	    set files $nf
+	}
+    }
 
+    set mergefilelist($diffmergeid) $files
+    if {$files ne {}} {
+	showmergediff
+    }
+}
+
+proc showmergediff {} {
+    global cflist diffmergeid mergefilelist parents
+    global diffopts diffinhunk currentfile currenthunk filelines
+    global diffblocked groupfilelast mergefds groupfilenum grouphunks
+
+    set files $mergefilelist($diffmergeid)
+    foreach f $files {
+	$cflist insert end $f
+    }
+    set env(GIT_DIFF_OPTS) $diffopts
+    set flist {}
+    catch {unset currentfile}
+    catch {unset currenthunk}
+    catch {unset filelines}
+    catch {unset groupfilenum}
+    catch {unset grouphunks}
+    set groupfilelast -1
+    foreach p $parents($diffmergeid) {
+	set cmd [list | git-diff-tree -p $p $diffmergeid]
+	set cmd [concat $cmd $mergefilelist($diffmergeid)]
+	if {[catch {set f [open $cmd r]} err]} {
+	    error_popup "Error getting diffs: $err"
+	    foreach f $flist {
+		catch {close $f}
+	    }
+	    return
+	}
+	lappend flist $f
+	set ids [list $diffmergeid $p]
+	set mergefds($ids) $f
+	set diffinhunk($ids) 0
+	set diffblocked($ids) 0
+	fconfigure $f -blocking 0
+	fileevent $f readable [list getmergediffline $f $ids $diffmergeid]
+    }
+}
+
+proc getmergediffline {f ids id} {
+    global diffmergeid diffinhunk diffoldlines diffnewlines
+    global currentfile currenthunk
+    global diffoldstart diffnewstart diffoldlno diffnewlno
+    global diffblocked mergefilelist
+    global noldlines nnewlines difflcounts filelines
+
+    set n [gets $f line]
+    if {$n < 0} {
+	if {![eof $f]} return
+    }
+
+    if {!([info exists diffmergeid] && $diffmergeid == $id)} {
+	if {$n < 0} {
+	    close $f
+	}
+	return
+    }
+
+    if {$diffinhunk($ids) != 0} {
+	set fi $currentfile($ids)
+	if {$n > 0 && [regexp {^[-+ \\]} $line match]} {
+	    # continuing an existing hunk
+	    set line [string range $line 1 end]
+	    set p [lindex $ids 1]
+	    if {$match eq "-" || $match eq " "} {
+		set filelines($p,$fi,$diffoldlno($ids)) $line
+		incr diffoldlno($ids)
+	    }
+	    if {$match eq "+" || $match eq " "} {
+		set filelines($id,$fi,$diffnewlno($ids)) $line
+		incr diffnewlno($ids)
+	    }
+	    if {$match eq " "} {
+		if {$diffinhunk($ids) == 2} {
+		    lappend difflcounts($ids) \
+			[list $noldlines($ids) $nnewlines($ids)]
+		    set noldlines($ids) 0
+		    set diffinhunk($ids) 1
+		}
+		incr noldlines($ids)
+	    } elseif {$match eq "-" || $match eq "+"} {
+		if {$diffinhunk($ids) == 1} {
+		    lappend difflcounts($ids) [list $noldlines($ids)]
+		    set noldlines($ids) 0
+		    set nnewlines($ids) 0
+		    set diffinhunk($ids) 2
+		}
+		if {$match eq "-"} {
+		    incr noldlines($ids)
+		} else {
+		    incr nnewlines($ids)
+		}
+	    }
+	    # and if it's \ No newline at end of line, then what?
+	    return
+	}
+	# end of a hunk
+	if {$diffinhunk($ids) == 1 && $noldlines($ids) != 0} {
+	    lappend difflcounts($ids) [list $noldlines($ids)]
+	} elseif {$diffinhunk($ids) == 2
+		  && ($noldlines($ids) != 0 || $nnewlines($ids) != 0)} {
+	    lappend difflcounts($ids) [list $noldlines($ids) $nnewlines($ids)]
+	}
+	set currenthunk($ids) [list $currentfile($ids) \
+				   $diffoldstart($ids) $diffnewstart($ids) \
+				   $diffoldlno($ids) $diffnewlno($ids) \
+				   $difflcounts($ids)]
+	set diffinhunk($ids) 0
+	# -1 = need to block, 0 = unblocked, 1 = is blocked
+	set diffblocked($ids) -1
+	processhunks
+	if {$diffblocked($ids) == -1} {
+	    fileevent $f readable {}
+	    set diffblocked($ids) 1
+	}
+    }
+
+    if {$n < 0} {
+	# eof
+	if {!$diffblocked($ids)} {
+	    close $f
+	    set currentfile($ids) [llength $mergefilelist($diffmergeid)]
+	    set currenthunk($ids) [list $currentfile($ids) 0 0 0 0 {}]
+	    processhunks
+	}
+    } elseif {[regexp {^diff --git a/(.*) b/} $line match fname]} {
+	# start of a new file
+	set currentfile($ids) \
+	    [lsearch -exact $mergefilelist($diffmergeid) $fname]
+    } elseif {[regexp {^@@ -([0-9]+),([0-9]+) \+([0-9]+),([0-9]+) @@(.*)} \
+		   $line match f1l f1c f2l f2c rest]} {
+	if {[info exists currentfile($ids)] && $currentfile($ids) >= 0} {
+	    # start of a new hunk
+	    if {$f1l == 0 && $f1c == 0} {
+		set f1l 1
+	    }
+	    if {$f2l == 0 && $f2c == 0} {
+		set f2l 1
+	    }
+	    set diffinhunk($ids) 1
+	    set diffoldstart($ids) $f1l
+	    set diffnewstart($ids) $f2l
+	    set diffoldlno($ids) $f1l
+	    set diffnewlno($ids) $f2l
+	    set difflcounts($ids) {}
+	    set noldlines($ids) 0
+	    set nnewlines($ids) 0
+	}
+    }
+}
+
+proc processhunks {} {
+    global diffmergeid parents nparents currenthunk
+    global mergefilelist diffblocked mergefds
+    global grouphunks grouplinestart grouplineend groupfilenum
+
+    set nfiles [llength $mergefilelist($diffmergeid)]
+    while 1 {
+	set fi $nfiles
+	set lno 0
+	# look for the earliest hunk
+	foreach p $parents($diffmergeid) {
+	    set ids [list $diffmergeid $p]
+	    if {![info exists currenthunk($ids)]} return
+	    set i [lindex $currenthunk($ids) 0]
+	    set l [lindex $currenthunk($ids) 2]
+	    if {$i < $fi || ($i == $fi && $l < $lno)} {
+		set fi $i
+		set lno $l
+		set pi $p
+	    }
+	}
+
+	if {$fi < $nfiles} {
+	    set ids [list $diffmergeid $pi]
+	    set hunk $currenthunk($ids)
+	    unset currenthunk($ids)
+	    if {$diffblocked($ids) > 0} {
+		fileevent $mergefds($ids) readable \
+		    [list getmergediffline $mergefds($ids) $ids $diffmergeid]
+	    }
+	    set diffblocked($ids) 0
+
+	    if {[info exists groupfilenum] && $groupfilenum == $fi
+		&& $lno <= $grouplineend} {
+		# add this hunk to the pending group
+		lappend grouphunks($pi) $hunk
+		set endln [lindex $hunk 4]
+		if {$endln > $grouplineend} {
+		    set grouplineend $endln
+		}
+		continue
+	    }
+	}
+
+	# succeeding stuff doesn't belong in this group, so
+	# process the group now
+	if {[info exists groupfilenum]} {
+	    processgroup
+	    unset groupfilenum
+	    unset grouphunks
+	}
+
+	if {$fi >= $nfiles} break
+
+	# start a new group
+	set groupfilenum $fi
+	set grouphunks($pi) [list $hunk]
+	set grouplinestart $lno
+	set grouplineend [lindex $hunk 4]
+    }
+}
+
+proc processgroup {} {
+    global groupfilelast groupfilenum difffilestart
+    global mergefilelist diffmergeid ctext filelines
+    global parents diffmergeid diffoffset
+    global grouphunks grouplinestart grouplineend nparents
+    global mergemax
+
+    $ctext conf -state normal
+    set id $diffmergeid
+    set f $groupfilenum
+    if {$groupfilelast != $f} {
+	$ctext insert end "\n"
+	set here [$ctext index "end - 1c"]
+	set difffilestart($f) $here
+	set mark fmark.[expr {$f + 1}]
+	$ctext mark set $mark $here
+	$ctext mark gravity $mark left
+	set header [lindex $mergefilelist($id) $f]
+	set l [expr {(78 - [string length $header]) / 2}]
+	set pad [string range "----------------------------------------" 1 $l]
+	$ctext insert end "$pad $header $pad\n" filesep
+	set groupfilelast $f
+	foreach p $parents($id) {
+	    set diffoffset($p) 0
+	}
+    }
+
+    $ctext insert end "@@" msep
+    set nlines [expr {$grouplineend - $grouplinestart}]
+    set events {}
+    set pnum 0
+    foreach p $parents($id) {
+	set startline [expr {$grouplinestart + $diffoffset($p)}]
+	set ol $startline
+	set nl $grouplinestart
+	if {[info exists grouphunks($p)]} {
+	    foreach h $grouphunks($p) {
+		set l [lindex $h 2]
+		if {$nl < $l} {
+		    for {} {$nl < $l} {incr nl} {
+			set filelines($p,$f,$ol) $filelines($id,$f,$nl)
+			incr ol
+		    }
+		}
+		foreach chunk [lindex $h 5] {
+		    if {[llength $chunk] == 2} {
+			set olc [lindex $chunk 0]
+			set nlc [lindex $chunk 1]
+			set nnl [expr {$nl + $nlc}]
+			lappend events [list $nl $nnl $pnum $olc $nlc]
+			incr ol $olc
+			set nl $nnl
+		    } else {
+			incr ol [lindex $chunk 0]
+			incr nl [lindex $chunk 0]
+		    }
+		}
+	    }
+	}
+	if {$nl < $grouplineend} {
+	    for {} {$nl < $grouplineend} {incr nl} {
+		set filelines($p,$f,$ol) $filelines($id,$f,$nl)
+		incr ol
+	    }
+	}
+	set nlines [expr {$ol - $startline}]
+	$ctext insert end " -$startline,$nlines" msep
+	incr pnum
+    }
+
+    set nlines [expr {$grouplineend - $grouplinestart}]
+    $ctext insert end " +$grouplinestart,$nlines @@\n" msep
+
+    set events [lsort -integer -index 0 $events]
+    set nevents [llength $events]
+    set nmerge $nparents($diffmergeid)
+    set l $grouplinestart
+    for {set i 0} {$i < $nevents} {set i $j} {
+	set nl [lindex $events $i 0]
+	while {$l < $nl} {
+	    $ctext insert end " $filelines($id,$f,$l)\n"
+	    incr l
+	}
+	set e [lindex $events $i]
+	set enl [lindex $e 1]
+	set j $i
+	set active {}
+	while 1 {
+	    set pnum [lindex $e 2]
+	    set olc [lindex $e 3]
+	    set nlc [lindex $e 4]
+	    if {![info exists delta($pnum)]} {
+		set delta($pnum) [expr {$olc - $nlc}]
+		lappend active $pnum
+	    } else {
+		incr delta($pnum) [expr {$olc - $nlc}]
+	    }
+	    if {[incr j] >= $nevents} break
+	    set e [lindex $events $j]
+	    if {[lindex $e 0] >= $enl} break
+	    if {[lindex $e 1] > $enl} {
+		set enl [lindex $e 1]
+	    }
+	}
+	set nlc [expr {$enl - $l}]
+	set ncol mresult
+	set bestpn -1
+	if {[llength $active] == $nmerge - 1} {
+	    # no diff for one of the parents, i.e. it's identical
+	    for {set pnum 0} {$pnum < $nmerge} {incr pnum} {
+		if {![info exists delta($pnum)]} {
+		    if {$pnum < $mergemax} {
+			lappend ncol m$pnum
+		    } else {
+			lappend ncol mmax
+		    }
+		    break
+		}
+	    }
+	} elseif {[llength $active] == $nmerge} {
+	    # all parents are different, see if one is very similar
+	    set bestsim 30
+	    for {set pnum 0} {$pnum < $nmerge} {incr pnum} {
+		set sim [similarity $pnum $l $nlc $f \
+			     [lrange $events $i [expr {$j-1}]]]
+		if {$sim > $bestsim} {
+		    set bestsim $sim
+		    set bestpn $pnum
+		}
+	    }
+	    if {$bestpn >= 0} {
+		lappend ncol m$bestpn
+	    }
+	}
+	set pnum -1
+	foreach p $parents($id) {
+	    incr pnum
+	    if {![info exists delta($pnum)] || $pnum == $bestpn} continue
+	    set olc [expr {$nlc + $delta($pnum)}]
+	    set ol [expr {$l + $diffoffset($p)}]
+	    incr diffoffset($p) $delta($pnum)
+	    unset delta($pnum)
+	    for {} {$olc > 0} {incr olc -1} {
+		$ctext insert end "-$filelines($p,$f,$ol)\n" m$pnum
+		incr ol
+	    }
+	}
+	set endl [expr {$l + $nlc}]
+	if {$bestpn >= 0} {
+	    # show this pretty much as a normal diff
+	    set p [lindex $parents($id) $bestpn]
+	    set ol [expr {$l + $diffoffset($p)}]
+	    incr diffoffset($p) $delta($bestpn)
+	    unset delta($bestpn)
+	    for {set k $i} {$k < $j} {incr k} {
+		set e [lindex $events $k]
+		if {[lindex $e 2] != $bestpn} continue
+		set nl [lindex $e 0]
+		set ol [expr {$ol + $nl - $l}]
+		for {} {$l < $nl} {incr l} {
+		    $ctext insert end "+$filelines($id,$f,$l)\n" $ncol
+		}
+		set c [lindex $e 3]
+		for {} {$c > 0} {incr c -1} {
+		    $ctext insert end "-$filelines($p,$f,$ol)\n" m$bestpn
+		    incr ol
+		}
+		set nl [lindex $e 1]
+		for {} {$l < $nl} {incr l} {
+		    $ctext insert end "+$filelines($id,$f,$l)\n" mresult
+		}
+	    }
+	}
+	for {} {$l < $endl} {incr l} {
+	    $ctext insert end "+$filelines($id,$f,$l)\n" $ncol
+	}
+    }
+    while {$l < $grouplineend} {
+	$ctext insert end " $filelines($id,$f,$l)\n"
+	incr l
+    }
+    $ctext conf -state disabled
+}
+
+proc similarity {pnum l nlc f events} {
+    global diffmergeid parents diffoffset filelines
+
+    set id $diffmergeid
+    set p [lindex $parents($id) $pnum]
+    set ol [expr {$l + $diffoffset($p)}]
+    set endl [expr {$l + $nlc}]
+    set same 0
+    set diff 0
+    foreach e $events {
+	if {[lindex $e 2] != $pnum} continue
+	set nl [lindex $e 0]
+	set ol [expr {$ol + $nl - $l}]
+	for {} {$l < $nl} {incr l} {
+	    incr same [string length $filelines($id,$f,$l)]
+	    incr same
+	}
+	set oc [lindex $e 3]
+	for {} {$oc > 0} {incr oc -1} {
+	    incr diff [string length $filelines($p,$f,$ol)]
+	    incr diff
+	    incr ol
+	}
+	set nl [lindex $e 1]
+	for {} {$l < $nl} {incr l} {
+	    incr diff [string length $filelines($id,$f,$l)]
+	    incr diff
+	}
+    }
+    for {} {$l < $endl} {incr l} {
+	incr same [string length $filelines($id,$f,$l)]
+	incr same
+    }
+    if {$same == 0} {
+	return 0
+    }
+    return [expr {200 * $same / (2 * $same + $diff)}]
+}
+
+proc startdiff {ids} {
+    global treediffs diffids treepending diffmergeid
+
+    set diffids $ids
+    catch {unset diffmergeid}
     if {![info exists treediffs($ids)]} {
-	set diffids $ids
 	if {![info exists treepending]} {
 	    gettreediffs $ids
 	}
@@ -1715,47 +2412,39 @@ proc contdiff {ids} {
     }
 }
 
-proc selnextline {dir} {
-    global selectedline
-    if {![info exists selectedline]} return
-    set l [expr $selectedline + $dir]
-    unmarkmatches
-    selectline $l
-}
-
 proc addtocflist {ids} {
-    global treediffs cflist diffpindex
-
-    set colors {black blue green red cyan magenta}
-    set color [lindex $colors [expr {$diffpindex % [llength $colors]}]]
+    global treediffs cflist
     foreach f $treediffs($ids) {
 	$cflist insert end $f
-	$cflist itemconf end -foreground $color
     }
     getblobdiffs $ids
 }
 
 proc gettreediffs {ids} {
-    global treediffs parents treepending
+    global treediff parents treepending
     set treepending $ids
-    set treediffs($ids) {}
+    set treediff {}
     set id [lindex $ids 0]
     set p [lindex $ids 1]
     if [catch {set gdtf [open "|git-diff-tree -r $p $id" r]}] return
     fconfigure $gdtf -blocking 0
-    fileevent $gdtf readable "gettreediffline $gdtf {$ids}"
+    fileevent $gdtf readable [list gettreediffline $gdtf $ids]
 }
 
 proc gettreediffline {gdtf ids} {
-    global treediffs treepending diffids
+    global treediff treediffs treepending diffids diffmergeid
+
     set n [gets $gdtf line]
     if {$n < 0} {
 	if {![eof $gdtf]} return
 	close $gdtf
+	set treediffs($ids) $treediff
 	unset treepending
-	if {[info exists diffids]} {
-	    if {$ids != $diffids} {
-		gettreediffs $diffids
+	if {$ids != $diffids} {
+	    gettreediffs $diffids
+	} else {
+	    if {[info exists diffmergeid]} {
+		contmergediff $ids
 	    } else {
 		addtocflist $ids
 	    }
@@ -1763,30 +2452,36 @@ proc gettreediffline {gdtf ids} {
 	return
     }
     set file [lindex $line 5]
-    lappend treediffs($ids) $file
+    lappend treediff $file
 }
 
 proc getblobdiffs {ids} {
-    global diffopts blobdifffd diffids env
-    global nextupdate
+    global diffopts blobdifffd diffids env curdifftag curtagstart
+    global difffilestart nextupdate diffinhdr treediffs
 
     set id [lindex $ids 0]
     set p [lindex $ids 1]
     set env(GIT_DIFF_OPTS) $diffopts
-    if [catch {set bdf [open "|git-diff-tree -r -p $p $id" r]} err] {
+    set cmd [list | git-diff-tree -r -p -C $p $id]
+    if {[catch {set bdf [open $cmd r]} err]} {
 	puts "error getting diffs: $err"
 	return
     }
+    set diffinhdr 0
     fconfigure $bdf -blocking 0
     set blobdifffd($ids) $bdf
-    fileevent $bdf readable [list getblobdiffline $bdf $ids]
+    set curdifftag Comments
+    set curtagstart 0.0
+    catch {unset difffilestart}
+    fileevent $bdf readable [list getblobdiffline $bdf $diffids]
     set nextupdate [expr {[clock clicks -milliseconds] + 100}]
 }
 
 proc getblobdiffline {bdf ids} {
-    global diffids blobdifffd ctext curdifftag curtagstart seenfile
-    global diffnexthead diffnextnote diffindex difffilestart
-    global nextupdate diffpending diffpindex
+    global diffids blobdifffd ctext curdifftag curtagstart
+    global diffnexthead diffnextnote difffilestart
+    global nextupdate diffinhdr treediffs
+    global gaudydiff
 
     set n [gets $bdf line]
     if {$n < 0} {
@@ -1794,12 +2489,6 @@ proc getblobdiffline {bdf ids} {
 	    close $bdf
 	    if {$ids == $diffids && $bdf == $blobdifffd($ids)} {
 		$ctext tag add $curdifftag $curtagstart end
-		set seenfile($curdifftag) 1
-		if {[incr diffpindex] < [llength $diffpending]} {
-		    set id [lindex $ids 0]
-		    set p [lindex $diffpending $diffpindex]
-		    contdiff [list $id $p]
-		}
 	    }
 	}
 	return
@@ -1808,60 +2497,61 @@ proc getblobdiffline {bdf ids} {
 	return
     }
     $ctext conf -state normal
-    if {[regexp {^---[ \t]+([^/])*/(.*)} $line match s1 fname]} {
+    if {[regexp {^diff --git a/(.*) b/(.*)} $line match fname newname]} {
 	# start of a new file
 	$ctext insert end "\n"
 	$ctext tag add $curdifftag $curtagstart end
-	set seenfile($curdifftag) 1
 	set curtagstart [$ctext index "end - 1c"]
-	set header $fname
-	if {[info exists diffnexthead]} {
-	    set fname $diffnexthead
-	    set header "$diffnexthead ($diffnextnote)"
-	    unset diffnexthead
-	}
+	set header $newname
 	set here [$ctext index "end - 1c"]
-	set difffilestart($diffindex) $here
-	incr diffindex
-	# start mark names at fmark.1 for first file
-	$ctext mark set fmark.$diffindex $here
-	$ctext mark gravity fmark.$diffindex left
+	set i [lsearch -exact $treediffs($diffids) $fname]
+	if {$i >= 0} {
+	    set difffilestart($i) $here
+	    incr i
+	    $ctext mark set fmark.$i $here
+	    $ctext mark gravity fmark.$i left
+	}
+	if {$newname != $fname} {
+	    set i [lsearch -exact $treediffs($diffids) $newname]
+	    if {$i >= 0} {
+		set difffilestart($i) $here
+		incr i
+		$ctext mark set fmark.$i $here
+		$ctext mark gravity fmark.$i left
+	    }
+	}
 	set curdifftag "f:$fname"
 	$ctext tag delete $curdifftag
 	set l [expr {(78 - [string length $header]) / 2}]
 	set pad [string range "----------------------------------------" 1 $l]
 	$ctext insert end "$pad $header $pad\n" filesep
-    } elseif {[string range $line 0 2] == "+++"} {
-	# no need to do anything with this
-    } elseif {[regexp {^Created: (.*) \((mode: *[0-7]*)\)} $line match fn m]} {
-	set diffnexthead $fn
-	set diffnextnote "created, mode $m"
-    } elseif {[string range $line 0 8] == "Deleted: "} {
-	set diffnexthead [string range $line 9 end]
-	set diffnextnote "deleted"
-    } elseif {[regexp {^diff --git a/(.*) b/} $line match fn]} {
-	# save the filename in case the next thing is "new file mode ..."
-	set diffnexthead $fn
-	set diffnextnote "modified"
-    } elseif {[regexp {^new file mode ([0-7]+)} $line match m]} {
-	set diffnextnote "new file, mode $m"
-    } elseif {[string range $line 0 11] == "deleted file"} {
-	set diffnextnote "deleted"
+	set diffinhdr 1
+    } elseif {[regexp {^(---|\+\+\+)} $line]} {
+	set diffinhdr 0
     } elseif {[regexp {^@@ -([0-9]+),([0-9]+) \+([0-9]+),([0-9]+) @@(.*)} \
 		   $line match f1l f1c f2l f2c rest]} {
-	$ctext insert end "\t" hunksep
-	$ctext insert end "    $f1l    " d0 "    $f2l    " d1
-	$ctext insert end "    $rest \n" hunksep
+	if {$gaudydiff} {
+	    $ctext insert end "\t" hunksep
+	    $ctext insert end "    $f1l    " d0 "    $f2l    " d1
+	    $ctext insert end "    $rest \n" hunksep
+	} else {
+	    $ctext insert end "$line\n" hunksep
+	}
+	set diffinhdr 0
     } else {
 	set x [string range $line 0 0]
 	if {$x == "-" || $x == "+"} {
 	    set tag [expr {$x == "+"}]
-	    set line [string range $line 1 end]
+	    if {$gaudydiff} {
+		set line [string range $line 1 end]
+	    }
 	    $ctext insert end "$line\n" d$tag
 	} elseif {$x == " "} {
-	    set line [string range $line 1 end]
+	    if {$gaudydiff} {
+		set line [string range $line 1 end]
+	    }
 	    $ctext insert end "$line\n"
-	} elseif {$x == "\\"} {
+	} elseif {$diffinhdr || $x == "\\"} {
 	    # e.g. "\ No newline at end of file"
 	    $ctext insert end "$line\n" filesep
 	} else {
@@ -1869,7 +2559,6 @@ proc getblobdiffline {bdf ids} {
 	    if {$curdifftag != "Comments"} {
 		$ctext insert end "\n"
 		$ctext tag add $curdifftag $curtagstart end
-		set seenfile($curdifftag) 1
 		set curtagstart [$ctext index "end - 1c"]
 		set curdifftag Comments
 	    }
@@ -1890,14 +2579,19 @@ proc nextfile {} {
     set here [$ctext index @0,0]
     for {set i 0} {[info exists difffilestart($i)]} {incr i} {
 	if {[$ctext compare $difffilestart($i) > $here]} {
-	    $ctext yview $difffilestart($i)
-	    break
+	    if {![info exists pos]
+		|| [$ctext compare $difffilestart($i) < $pos]} {
+		set pos $difffilestart($i)
+	    }
 	}
     }
+    if {[info exists pos]} {
+	$ctext yview $pos
+    }
 }
 
 proc listboxsel {} {
-    global ctext cflist currentid treediffs
+    global ctext cflist currentid
     if {![info exists currentid]} return
     set sel [lsort [$cflist curselection]]
     if {$sel eq {}} return
@@ -1907,10 +2601,14 @@ proc listboxsel {} {
 
 proc setcoords {} {
     global linespc charspc canvx0 canvy0 mainfont
+    global xspc1 xspc2
+
     set linespc [font metrics $mainfont -linespace]
     set charspc [font measure $mainfont "m"]
     set canvy0 [expr 3 + 0.5 * $linespc]
     set canvx0 [expr 3 + 0.5 * $linespc]
+    set xspc1(0) $linespc
+    set xspc2 $linespc
 }
 
 proc redisplay {} {
@@ -1969,18 +2667,35 @@ proc sha1change {n1 n2 op} {
 
 proc gotocommit {} {
     global sha1string currentid idline tagids
+    global lineid numcommits
+
     if {$sha1string == {}
 	|| ([info exists currentid] && $sha1string == $currentid)} return
     if {[info exists tagids($sha1string)]} {
 	set id $tagids($sha1string)
     } else {
 	set id [string tolower $sha1string]
+	if {[regexp {^[0-9a-f]{4,39}$} $id]} {
+	    set matches {}
+	    for {set l 0} {$l < $numcommits} {incr l} {
+		if {[string match $id* $lineid($l)]} {
+		    lappend matches $lineid($l)
+		}
+	    }
+	    if {$matches ne {}} {
+		if {[llength $matches] > 1} {
+		    error_popup "Short SHA1 id $id is ambiguous"
+		    return
+		}
+		set id [lindex $matches 0]
+	    }
+	}
     }
     if {[info exists idline($id)]} {
-	selectline $idline($id)
+	selectline $idline($id) 1
 	return
     }
-    if {[regexp {^[0-9a-fA-F]{40}$} $sha1string]} {
+    if {[regexp {^[0-9a-fA-F]{4,}$} $sha1string]} {
 	set type "SHA1 id"
     } else {
 	set type "Tag"
@@ -2089,7 +2804,7 @@ proc lineclick {x y id} {
 proc selbyid {id} {
     global idline
     if {[info exists idline($id)]} {
-	selectline $idline($id)
+	selectline $idline($id) 1
     }
 }
 
@@ -2277,10 +2992,7 @@ proc domktag {} {
 	return
     }
     if {[catch {
-	set dir ".git"
-	if {[info exists env(GIT_DIR)]} {
-	    set dir $env(GIT_DIR)
-	}
+	set dir [gitdir]
 	set fname [file join $dir "refs/tags" $tag]
 	set f [open $fname w]
 	puts $f $id
@@ -2296,7 +3008,7 @@ proc domktag {} {
     set xt [eval drawtags $id $idpos($id)]
     $canv coords $linehtag($idline($id)) $xt [lindex $idpos($id) 2]
     if {[info exists selectedline] && $selectedline == $idline($id)} {
-	selectline $selectedline
+	selectline $selectedline 0
     }
 }
 
@@ -2382,6 +3094,8 @@ set wrcomcmd "git-diff-tree --stdin -p --pretty"
 set mainfont {Helvetica 9}
 set textfont {Courier 9}
 set findmergefiles 0
+set gaudydiff 0
+set maxgraphpct 50
 
 set colors {green red blue magenta darkgrey brown orange}
 
@@ -2404,6 +3118,9 @@ foreach arg $argv {
     }
 }
 
+set history {}
+set historyindex 0
+
 set stopped 0
 set redisplaying 0
 set stuffsaved 0