X-Git-Url: https://git.octo.it/?a=blobdiff_plain;f=gitk;h=2aa970d5cffea4bea0e3f8f1a100f68b53e5a7af;hb=e468305a954d95a26bfcdec3bc6e4bd477d95676;hp=fc763ba9c8d2af94003f99abf8f92e2f43698d23;hpb=8a0a74ad7764db655f07c464ce931cc233f550b5;p=git.git

diff --git a/gitk b/gitk
index fc763ba9..2aa970d5 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
@@ -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
@@ -81,16 +86,21 @@ to allow selection of commits to be displayed.)}
     while 1 {
 	set i [string first "\0" $stuff $start]
 	if {$i < 0} {
-	    set leftover [string range $stuff $start end]
+	    append leftover [string range $stuff $start end]
 	    return
 	}
 	set cmit [string range $stuff $start [expr {$i - 1}]]
 	if {$start == 0} {
 	    set cmit "$leftover$cmit"
+	    set leftover {}
 	}
 	set start [expr {$i + 1}]
 	if {![regexp {^([0-9a-f]{40})\n} $cmit match id]} {
-	    error_popup "Can't parse git-rev-list output: {$cmit}"
+	    set shortcmit $cmit
+	    if {[string length $shortcmit] > 80} {
+		set shortcmit "[string range $shortcmit 0 80]..."
+	    }
+	    error_popup "Can't parse git-rev-list output: {$shortcmit}"
 	    exit 1
 	}
 	set cmit [string range $cmit 41 end]
@@ -207,7 +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]
@@ -236,7 +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]
@@ -265,10 +275,10 @@ proc error_popup msg {
 
 proc makewindow {} {
     global canv canv2 canv3 linespc charspc ctext cflist textfont
-    global findtype findloc findstring fstring geometry
+    global findtype findtypemenu findloc findstring fstring geometry
     global entries sha1entry sha1string sha1but
     global maincursor textcursor
-    global rowctxmenu
+    global rowctxmenu gaudydiff mergemax
 
     menu .bar
     .bar add cascade -label "File" -menu .bar.file
@@ -337,12 +347,15 @@ proc makewindow {} {
     entry $fstring -width 30 -font $textfont -textvariable findstring
     pack $fstring -side left -expand 1 -fill x
     set findtype Exact
-    tk_optionMenu .ctop.top.bar.findtype findtype Exact IgnCase Regexp
+    set findtypemenu [tk_optionMenu .ctop.top.bar.findtype \
+			  findtype Exact IgnCase Regexp]
     set findloc "All fields"
     tk_optionMenu .ctop.top.bar.findloc findloc "All fields" Headline \
-	Comments Author Committer
+	Comments Author Committer Files Pickaxe
     pack .ctop.top.bar.findloc -side right
     pack .ctop.top.bar.findtype -side right
+    # for making sure type==Exact whenever loc==Pickaxe
+    trace add variable findloc write findlocchange
 
     panedwindow .ctop.cdet -orient horizontal
     .ctop add .ctop.cdet
@@ -356,11 +369,26 @@ 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
@@ -392,12 +420,13 @@ proc makewindow {} {
     bindkey b "$ctext yview scroll -1 pages"
     bindkey d "$ctext yview scroll 18 units"
     bindkey u "$ctext yview scroll -18 units"
-    bindkey / findnext
+    bindkey / {findnext 1}
+    bindkey <Key-Return> {findnext 0}
     bindkey ? findprev
     bindkey f nextfile
     bind . <Control-q> doquit
     bind . <Control-f> dofind
-    bind . <Control-g> findnext
+    bind . <Control-g> {findnext 0}
     bind . <Control-r> findprev
     bind . <Control-equal> {incrfont 1}
     bind . <Control-KP_Add> {incrfont 1}
@@ -419,6 +448,9 @@ proc makewindow {} {
 	-command {diffvssel 0}
     $rowctxmenu add command -label "Diff selected -> this" \
 	-command {diffvssel 1}
+    $rowctxmenu add command -label "Make patch" -command mkpatch
+    $rowctxmenu add command -label "Create tag" -command mktag
+    $rowctxmenu add command -label "Write commit to file" -command writecommit
 }
 
 # when we make a key binding for the toplevel, make sure
@@ -448,13 +480,16 @@ proc click {w} {
 
 proc savestuff {w} {
     global canv canv2 canv3 ctext cflist mainfont textfont
-    global stuffsaved
+    global stuffsaved findmergefiles gaudydiff
+
     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 "set geometry(width) [winfo width .ctop]"
 	puts $f "set geometry(height) [winfo height .ctop]"
 	puts $f "set geometry(canv1) [expr [winfo width $canv]-2]"
@@ -665,7 +700,7 @@ proc drawcommitline {level} {
     global oldlevel oldnlines oldtodo
     global idtags idline idheads
     global lineno lthickness mainline sidelines
-    global commitlisted rowtextx
+    global commitlisted rowtextx idpos
 
     incr numcommits
     incr lineno
@@ -726,47 +761,9 @@ proc drawcommitline {level} {
 	set xt [expr {$xt + ([llength $currentparents] - 2) * $linespc}]
     }
     set rowtextx($lineno) $xt
-    set marks {}
-    set ntags 0
-    if {[info exists idtags($id)]} {
-	set marks $idtags($id)
-	set ntags [llength $marks]
-    }
-    if {[info exists idheads($id)]} {
-	set marks [concat $marks $idheads($id)]
-    }
-    if {$marks != {}} {
-	set delta [expr {int(0.5 * ($linespc - $lthickness))}]
-	set yt [expr $y1 - 0.5 * $linespc]
-	set yb [expr $yt + $linespc - 1]
-	set xvals {}
-	set wvals {}
-	foreach tag $marks {
-	    set wid [font measure $mainfont $tag]
-	    lappend xvals $xt
-	    lappend wvals $wid
-	    set xt [expr {$xt + $delta + $wid + $lthickness + $linespc}]
-	}
-	set t [$canv create line $x $y1 [lindex $xvals end] $y1 \
-		   -width $lthickness -fill black]
-	$canv lower $t
-	foreach tag $marks x $xvals wid $wvals {
-	    set xl [expr $x + $delta]
-	    set xr [expr $x + $delta + $wid + $lthickness]
-	    if {[incr ntags -1] >= 0} {
-		# draw a tag
-		$canv create polygon $x [expr $yt + $delta] $xl $yt\
-		    $xr $yt $xr $yb $xl $yb $x [expr $yb - $delta] \
-		    -width 1 -outline black -fill yellow
-	    } else {
-		# draw a head
-		set xl [expr $xl - $delta/2]
-		$canv create polygon $x $yt $xr $yt $xr $yb $x $yb \
-		    -width 1 -outline black -fill green
-	    }
-	    $canv create text $xl $y1 -anchor w -text $tag \
-		-font $mainfont
-	}
+    set idpos($id) [list $x $xt $y1]
+    if {[info exists idtags($id)] || [info exists idheads($id)]} {
+	set xt [drawtags $id $x $xt $y1]
     }
     set headline [lindex $commitinfo($id) 0]
     set name [lindex $commitinfo($id) 1]
@@ -780,6 +777,58 @@ proc drawcommitline {level} {
 			       -text $date -font $mainfont]
 }
 
+proc drawtags {id x xt y1} {
+    global idtags idheads
+    global linespc lthickness
+    global canv mainfont
+
+    set marks {}
+    set ntags 0
+    if {[info exists idtags($id)]} {
+	set marks $idtags($id)
+	set ntags [llength $marks]
+    }
+    if {[info exists idheads($id)]} {
+	set marks [concat $marks $idheads($id)]
+    }
+    if {$marks eq {}} {
+	return $xt
+    }
+
+    set delta [expr {int(0.5 * ($linespc - $lthickness))}]
+    set yt [expr $y1 - 0.5 * $linespc]
+    set yb [expr $yt + $linespc - 1]
+    set xvals {}
+    set wvals {}
+    foreach tag $marks {
+	set wid [font measure $mainfont $tag]
+	lappend xvals $xt
+	lappend wvals $wid
+	set xt [expr {$xt + $delta + $wid + $lthickness + $linespc}]
+    }
+    set t [$canv create line $x $y1 [lindex $xvals end] $y1 \
+	       -width $lthickness -fill black -tags tag.$id]
+    $canv lower $t
+    foreach tag $marks x $xvals wid $wvals {
+	set xl [expr $x + $delta]
+	set xr [expr $x + $delta + $wid + $lthickness]
+	if {[incr ntags -1] >= 0} {
+	    # draw a tag
+	    $canv create polygon $x [expr $yt + $delta] $xl $yt\
+		$xr $yt $xr $yb $xl $yb $x [expr $yb - $delta] \
+		-width 1 -outline black -fill yellow -tags tag.$id
+	} else {
+	    # draw a head
+	    set xl [expr $xl - $delta/2]
+	    $canv create polygon $x $yt $xr $yt $xr $yb $x $yb \
+		-width 1 -outline black -fill green -tags tag.$id
+	}
+	$canv create text $xl $y1 -anchor w -text $tag \
+	    -font $mainfont -tags tag.$id
+    }
+    return $xt
+}
+
 proc updatetodo {level noshortcut} {
     global currentparents ncleft todo
     global mainline oldlevel oldtodo oldnlines
@@ -1114,10 +1163,15 @@ proc dofind {} {
     global numcommits lineid linehtag linentag linedtag
     global mainfont namefont canv canv2 canv3 selectedline
     global matchinglines foundstring foundstrlen
+
+    stopfindproc
     unmarkmatches
     focus .
     set matchinglines {}
-    set fldtypes {Headline Author Date Committer CDate Comment}
+    if {$findloc == "Pickaxe"} {
+	findpatches
+	return
+    }
     if {$findtype == "IgnCase"} {
 	set foundstring [string tolower $findstring]
     } else {
@@ -1125,12 +1179,17 @@ proc dofind {} {
     }
     set foundstrlen [string length $findstring]
     if {$foundstrlen == 0} return
+    if {$findloc == "Files"} {
+	findfiles
+	return
+    }
     if {![info exists selectedline]} {
 	set oldsel -1
     } else {
 	set oldsel $selectedline
     }
     set didsel 0
+    set fldtypes {Headline Author Date Committer CDate Comment}
     for {set l 0} {$l < $numcommits} {incr l} {
 	set id $lineid($l)
 	set info $commitinfo($id)
@@ -1180,10 +1239,12 @@ proc findselectline {l} {
     }
 }
 
-proc findnext {} {
+proc findnext {restart} {
     global matchinglines selectedline
     if {![info exists matchinglines]} {
-	dofind
+	if {$restart} {
+	    dofind
+	}
 	return
     }
     if {![info exists selectedline]} return
@@ -1215,6 +1276,308 @@ proc findprev {} {
     }
 }
 
+proc findlocchange {name ix op} {
+    global findloc findtype findtypemenu
+    if {$findloc == "Pickaxe"} {
+	set findtype Exact
+	set state disabled
+    } else {
+	set state normal
+    }
+    $findtypemenu entryconf 1 -state $state
+    $findtypemenu entryconf 2 -state $state
+}
+
+proc stopfindproc {{done 0}} {
+    global findprocpid findprocfile findids
+    global ctext findoldcursor phase maincursor textcursor
+    global findinprogress
+
+    catch {unset findids}
+    if {[info exists findprocpid]} {
+	if {!$done} {
+	    catch {exec kill $findprocpid}
+	}
+	catch {close $findprocfile}
+	unset findprocpid
+    }
+    if {[info exists findinprogress]} {
+	unset findinprogress
+	if {$phase != "incrdraw"} {
+	    . config -cursor $maincursor
+	    $ctext config -cursor $textcursor
+	}
+    }
+}
+
+proc findpatches {} {
+    global findstring selectedline numcommits
+    global findprocpid findprocfile
+    global finddidsel ctext lineid findinprogress
+    global findinsertpos
+
+    if {$numcommits == 0} return
+
+    # make a list of all the ids to search, starting at the one
+    # after the selected line (if any)
+    if {[info exists selectedline]} {
+	set l $selectedline
+    } else {
+	set l -1
+    }
+    set inputids {}
+    for {set i 0} {$i < $numcommits} {incr i} {
+	if {[incr l] >= $numcommits} {
+	    set l 0
+	}
+	append inputids $lineid($l) "\n"
+    }
+
+    if {[catch {
+	set f [open [list | git-diff-tree --stdin -s -r -S$findstring \
+			 << $inputids] r]
+    } err]} {
+	error_popup "Error starting search process: $err"
+	return
+    }
+
+    set findinsertpos end
+    set findprocfile $f
+    set findprocpid [pid $f]
+    fconfigure $f -blocking 0
+    fileevent $f readable readfindproc
+    set finddidsel 0
+    . config -cursor watch
+    $ctext config -cursor watch
+    set findinprogress 1
+}
+
+proc readfindproc {} {
+    global findprocfile finddidsel
+    global idline matchinglines findinsertpos
+
+    set n [gets $findprocfile line]
+    if {$n < 0} {
+	if {[eof $findprocfile]} {
+	    stopfindproc 1
+	    if {!$finddidsel} {
+		bell
+	    }
+	}
+	return
+    }
+    if {![regexp {^[0-9a-f]{40}} $line id]} {
+	error_popup "Can't parse git-diff-tree output: $line"
+	stopfindproc
+	return
+    }
+    if {![info exists idline($id)]} {
+	puts stderr "spurious id: $id"
+	return
+    }
+    set l $idline($id)
+    insertmatch $l $id
+}
+
+proc insertmatch {l id} {
+    global matchinglines findinsertpos finddidsel
+
+    if {$findinsertpos == "end"} {
+	if {$matchinglines != {} && $l < [lindex $matchinglines 0]} {
+	    set matchinglines [linsert $matchinglines 0 $l]
+	    set findinsertpos 1
+	} else {
+	    lappend matchinglines $l
+	}
+    } else {
+	set matchinglines [linsert $matchinglines $findinsertpos $l]
+	incr findinsertpos
+    }
+    markheadline $l $id
+    if {!$finddidsel} {
+	findselectline $l
+	set finddidsel 1
+    }
+}
+
+proc findfiles {} {
+    global selectedline numcommits lineid ctext
+    global ffileline finddidsel parents nparents
+    global findinprogress findstartline findinsertpos
+    global treediffs fdiffids fdiffsneeded fdiffpos
+    global findmergefiles
+
+    if {$numcommits == 0} return
+
+    if {[info exists selectedline]} {
+	set l [expr {$selectedline + 1}]
+    } else {
+	set l 0
+    }
+    set ffileline $l
+    set findstartline $l
+    set diffsneeded {}
+    set fdiffsneeded {}
+    while 1 {
+	set id $lineid($l)
+	if {$findmergefiles || $nparents($id) == 1} {
+	    foreach p $parents($id) {
+		if {![info exists treediffs([list $id $p])]} {
+		    append diffsneeded "$id $p\n"
+		    lappend fdiffsneeded [list $id $p]
+		}
+	    }
+	}
+	if {[incr l] >= $numcommits} {
+	    set l 0
+	}
+	if {$l == $findstartline} break
+    }
+
+    # start off a git-diff-tree process if needed
+    if {$diffsneeded ne {}} {
+	if {[catch {
+	    set df [open [list | git-diff-tree -r --stdin << $diffsneeded] r]
+	} err ]} {
+	    error_popup "Error starting search process: $err"
+	    return
+	}
+	catch {unset fdiffids}
+	set fdiffpos 0
+	fconfigure $df -blocking 0
+	fileevent $df readable [list readfilediffs $df]
+    }
+
+    set finddidsel 0
+    set findinsertpos end
+    set id $lineid($l)
+    set p [lindex $parents($id) 0]
+    . config -cursor watch
+    $ctext config -cursor watch
+    set findinprogress 1
+    findcont [list $id $p]
+    update
+}
+
+proc readfilediffs {df} {
+    global findids fdiffids fdiffs
+
+    set n [gets $df line]
+    if {$n < 0} {
+	if {[eof $df]} {
+	    donefilediff
+	    if {[catch {close $df} err]} {
+		stopfindproc
+		bell
+		error_popup "Error in git-diff-tree: $err"
+	    } elseif {[info exists findids]} {
+		set ids $findids
+		stopfindproc
+		bell
+		error_popup "Couldn't find diffs for {$ids}"
+	    }
+	}
+	return
+    }
+    if {[regexp {^([0-9a-f]{40}) \(from ([0-9a-f]{40})\)} $line match id p]} {
+	# start of a new string of diffs
+	donefilediff
+	set fdiffids [list $id $p]
+	set fdiffs {}
+    } elseif {[string match ":*" $line]} {
+	lappend fdiffs [lindex $line 5]
+    }
+}
+
+proc donefilediff {} {
+    global fdiffids fdiffs treediffs findids
+    global fdiffsneeded fdiffpos
+
+    if {[info exists fdiffids]} {
+	while {[lindex $fdiffsneeded $fdiffpos] ne $fdiffids
+	       && $fdiffpos < [llength $fdiffsneeded]} {
+	    # git-diff-tree doesn't output anything for a commit
+	    # which doesn't change anything
+	    set nullids [lindex $fdiffsneeded $fdiffpos]
+	    set treediffs($nullids) {}
+	    if {[info exists findids] && $nullids eq $findids} {
+		unset findids
+		findcont $nullids
+	    }
+	    incr fdiffpos
+	}
+	incr fdiffpos
+
+	if {![info exists treediffs($fdiffids)]} {
+	    set treediffs($fdiffids) $fdiffs
+	}
+	if {[info exists findids] && $fdiffids eq $findids} {
+	    unset findids
+	    findcont $fdiffids
+	}
+    }
+}
+
+proc findcont {ids} {
+    global findids treediffs parents nparents
+    global ffileline findstartline finddidsel
+    global lineid numcommits matchinglines findinprogress
+    global findmergefiles
+
+    set id [lindex $ids 0]
+    set p [lindex $ids 1]
+    set pi [lsearch -exact $parents($id) $p]
+    set l $ffileline
+    while 1 {
+	if {$findmergefiles || $nparents($id) == 1} {
+	    if {![info exists treediffs($ids)]} {
+		set findids $ids
+		set ffileline $l
+		return
+	    }
+	    set doesmatch 0
+	    foreach f $treediffs($ids) {
+		set x [findmatches $f]
+		if {$x != {}} {
+		    set doesmatch 1
+		    break
+		}
+	    }
+	    if {$doesmatch} {
+		insertmatch $l $id
+		set pi $nparents($id)
+	    }
+	} else {
+	    set pi $nparents($id)
+	}
+	if {[incr pi] >= $nparents($id)} {
+	    set pi 0
+	    if {[incr l] >= $numcommits} {
+		set l 0
+	    }
+	    if {$l == $findstartline} break
+	    set id $lineid($l)
+	}
+	set p [lindex $parents($id) $pi]
+	set ids [list $id $p]
+    }
+    stopfindproc
+    if {!$finddidsel} {
+	bell
+    }
+}
+
+# mark a commit as matching by putting a yellow background
+# behind the headline
+proc markheadline {l id} {
+    global canv mainfont linehtag commitinfo
+
+    set bbox [$canv bbox $linehtag($l)]
+    set t [$canv create rect $bbox -outline {} -tags matches -fill yellow]
+    $canv lower $t
+}
+
+# mark the bits of a headline, author or date that match a find string
 proc markmatches {canv l str tag matches font} {
     set bbox [$canv bbox $tag]
     set x0 [lindex $bbox 0]
@@ -1233,9 +1596,10 @@ proc markmatches {canv l str tag matches font} {
 }
 
 proc unmarkmatches {} {
-    global matchinglines
+    global matchinglines findids
     allcanvs delete matches
     catch {unset matchinglines}
+    catch {unset findids}
 }
 
 proc selcanvline {w x y} {
@@ -1260,8 +1624,8 @@ proc selectline {l} {
     global canv canv2 canv3 ctext commitinfo selectedline
     global lineid linehtag linentag linedtag
     global canvy0 linespc parents nparents
-    global cflist currentid sha1entry diffids
-    global commentend seenfile idtags
+    global cflist currentid sha1entry
+    global commentend idtags
     $canv delete hover
     if {![info exists lineid($l)] || ![info exists linehtag($l)]} return
     $canv delete secsel
@@ -1314,7 +1678,6 @@ proc selectline {l} {
 
     set id $lineid($l)
     set currentid $id
-    set diffids [concat $id $parents($id)]
     $sha1entry delete 0 end
     $sha1entry insert 0 $id
     $sha1entry selection from 0
@@ -1345,20 +1708,9 @@ proc selectline {l} {
     $cflist delete 0 end
     $cflist insert end "Comments"
     if {$nparents($id) == 1} {
-	startdiff
-    }
-    catch {unset seenfile}
-}
-
-proc startdiff {} {
-    global treediffs diffids treepending
-
-    if {![info exists treediffs($diffids)]} {
-	if {![info exists treepending]} {
-	    gettreediffs $diffids
-	}
-    } else {
-	addtocflist $diffids
+	startdiff [concat $id $parents($id)]
+    } elseif {$nparents($id) > 1} {
+	mergediff $id
     }
 }
 
@@ -1370,12 +1722,544 @@ proc selnextline {dir} {
     selectline $l
 }
 
-proc addtocflist {ids} {
-    global diffids treediffs cflist
-    if {$ids != $diffids} {
-	gettreediffs $diffids
+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)]} {
+	showmergediff
+    } else {
+	contmergediff {}
+    }
+}
+
+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
+
+    # 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 diffblocked
+    global groupfilelast mergefds
+
+    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}
+    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)]} {
+	if {![info exists treepending]} {
+	    gettreediffs $ids
+	}
+    } else {
+	addtocflist $ids
+    }
+}
+
+proc addtocflist {ids} {
+    global treediffs cflist
     foreach f $treediffs($ids) {
 	$cflist insert end $f
     }
@@ -1383,55 +2267,67 @@ proc addtocflist {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
+    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
-	addtocflist $ids
+	if {$ids != $diffids} {
+	    gettreediffs $diffids
+	} else {
+	    if {[info exists diffmergeid]} {
+		contmergediff $ids
+	    } else {
+		addtocflist $ids
+	    }
+	}
 	return
     }
     set file [lindex $line 5]
-    lappend treediffs($ids) $file
+    lappend treediff $file
 }
 
 proc getblobdiffs {ids} {
-    global diffopts blobdifffd env curdifftag curtagstart
-    global diffindex difffilestart 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
     set curdifftag Comments
     set curtagstart 0.0
-    set diffindex 0
     catch {unset difffilestart}
-    fileevent $bdf readable "getblobdiffline $bdf {$ids}"
+    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
+    global diffids blobdifffd ctext curdifftag curtagstart
+    global diffnexthead diffnextnote difffilestart
+    global nextupdate diffinhdr treediffs
+    global gaudydiff
 
     set n [gets $bdf line]
     if {$n < 0} {
@@ -1439,7 +2335,6 @@ proc getblobdiffline {bdf ids} {
 	    close $bdf
 	    if {$ids == $diffids && $bdf == $blobdifffd($ids)} {
 		$ctext tag add $curdifftag $curtagstart end
-		set seenfile($curdifftag) 1
 	    }
 	}
 	return
@@ -1448,60 +2343,61 @@ 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 {
@@ -1509,7 +2405,6 @@ proc getblobdiffline {bdf ids} {
 	    if {$curdifftag != "Comments"} {
 		$ctext insert end "\n"
 		$ctext tag add $curdifftag $curtagstart end
-		set seenfile($curdifftag) 1
 		set curtagstart [$ctext index "end - 1c"]
 		set curdifftag Comments
 	    }
@@ -1530,14 +2425,19 @@ proc nextfile {} {
     set here [$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 seenfile
+    global ctext cflist currentid
     if {![info exists currentid]} return
     set sel [lsort [$cflist curselection]]
     if {$sel eq {}} return
@@ -1609,18 +2509,35 @@ 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)
 	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"
@@ -1751,6 +2668,7 @@ proc rowmenu {x y id} {
     }
     $rowctxmenu entryconfigure 0 -state $state
     $rowctxmenu entryconfigure 1 -state $state
+    $rowctxmenu entryconfigure 2 -state $state
     set rowmenuid $id
     tk_popup $rowctxmenu $x $y
 }
@@ -1758,7 +2676,7 @@ proc rowmenu {x y id} {
 proc diffvssel {dirn} {
     global rowmenuid selectedline lineid
     global ctext cflist
-    global diffids commitinfo
+    global commitinfo
 
     if {![info exists selectedline]} return
     if {$dirn} {
@@ -1782,8 +2700,225 @@ proc diffvssel {dirn} {
     $ctext conf -state disabled
     $ctext tag delete Comments
     $ctext tag remove found 1.0 end
-    set diffids [list $newid $oldid]
-    startdiff
+    startdiff $newid [list $oldid]
+}
+
+proc mkpatch {} {
+    global rowmenuid currentid commitinfo patchtop patchnum
+
+    if {![info exists currentid]} return
+    set oldid $currentid
+    set oldhead [lindex $commitinfo($oldid) 0]
+    set newid $rowmenuid
+    set newhead [lindex $commitinfo($newid) 0]
+    set top .patch
+    set patchtop $top
+    catch {destroy $top}
+    toplevel $top
+    label $top.title -text "Generate patch"
+    grid $top.title - -pady 10
+    label $top.from -text "From:"
+    entry $top.fromsha1 -width 40 -relief flat
+    $top.fromsha1 insert 0 $oldid
+    $top.fromsha1 conf -state readonly
+    grid $top.from $top.fromsha1 -sticky w
+    entry $top.fromhead -width 60 -relief flat
+    $top.fromhead insert 0 $oldhead
+    $top.fromhead conf -state readonly
+    grid x $top.fromhead -sticky w
+    label $top.to -text "To:"
+    entry $top.tosha1 -width 40 -relief flat
+    $top.tosha1 insert 0 $newid
+    $top.tosha1 conf -state readonly
+    grid $top.to $top.tosha1 -sticky w
+    entry $top.tohead -width 60 -relief flat
+    $top.tohead insert 0 $newhead
+    $top.tohead conf -state readonly
+    grid x $top.tohead -sticky w
+    button $top.rev -text "Reverse" -command mkpatchrev -padx 5
+    grid $top.rev x -pady 10
+    label $top.flab -text "Output file:"
+    entry $top.fname -width 60
+    $top.fname insert 0 [file normalize "patch$patchnum.patch"]
+    incr patchnum
+    grid $top.flab $top.fname -sticky w
+    frame $top.buts
+    button $top.buts.gen -text "Generate" -command mkpatchgo
+    button $top.buts.can -text "Cancel" -command mkpatchcan
+    grid $top.buts.gen $top.buts.can
+    grid columnconfigure $top.buts 0 -weight 1 -uniform a
+    grid columnconfigure $top.buts 1 -weight 1 -uniform a
+    grid $top.buts - -pady 10 -sticky ew
+    focus $top.fname
+}
+
+proc mkpatchrev {} {
+    global patchtop
+
+    set oldid [$patchtop.fromsha1 get]
+    set oldhead [$patchtop.fromhead get]
+    set newid [$patchtop.tosha1 get]
+    set newhead [$patchtop.tohead get]
+    foreach e [list fromsha1 fromhead tosha1 tohead] \
+	    v [list $newid $newhead $oldid $oldhead] {
+	$patchtop.$e conf -state normal
+	$patchtop.$e delete 0 end
+	$patchtop.$e insert 0 $v
+	$patchtop.$e conf -state readonly
+    }
+}
+
+proc mkpatchgo {} {
+    global patchtop
+
+    set oldid [$patchtop.fromsha1 get]
+    set newid [$patchtop.tosha1 get]
+    set fname [$patchtop.fname get]
+    if {[catch {exec git-diff-tree -p $oldid $newid >$fname &} err]} {
+	error_popup "Error creating patch: $err"
+    }
+    catch {destroy $patchtop}
+    unset patchtop
+}
+
+proc mkpatchcan {} {
+    global patchtop
+
+    catch {destroy $patchtop}
+    unset patchtop
+}
+
+proc mktag {} {
+    global rowmenuid mktagtop commitinfo
+
+    set top .maketag
+    set mktagtop $top
+    catch {destroy $top}
+    toplevel $top
+    label $top.title -text "Create tag"
+    grid $top.title - -pady 10
+    label $top.id -text "ID:"
+    entry $top.sha1 -width 40 -relief flat
+    $top.sha1 insert 0 $rowmenuid
+    $top.sha1 conf -state readonly
+    grid $top.id $top.sha1 -sticky w
+    entry $top.head -width 60 -relief flat
+    $top.head insert 0 [lindex $commitinfo($rowmenuid) 0]
+    $top.head conf -state readonly
+    grid x $top.head -sticky w
+    label $top.tlab -text "Tag name:"
+    entry $top.tag -width 60
+    grid $top.tlab $top.tag -sticky w
+    frame $top.buts
+    button $top.buts.gen -text "Create" -command mktaggo
+    button $top.buts.can -text "Cancel" -command mktagcan
+    grid $top.buts.gen $top.buts.can
+    grid columnconfigure $top.buts 0 -weight 1 -uniform a
+    grid columnconfigure $top.buts 1 -weight 1 -uniform a
+    grid $top.buts - -pady 10 -sticky ew
+    focus $top.tag
+}
+
+proc domktag {} {
+    global mktagtop env tagids idtags
+    global idpos idline linehtag canv selectedline
+
+    set id [$mktagtop.sha1 get]
+    set tag [$mktagtop.tag get]
+    if {$tag == {}} {
+	error_popup "No tag name specified"
+	return
+    }
+    if {[info exists tagids($tag)]} {
+	error_popup "Tag \"$tag\" already exists"
+	return
+    }
+    if {[catch {
+	set dir [gitdir]
+	set fname [file join $dir "refs/tags" $tag]
+	set f [open $fname w]
+	puts $f $id
+	close $f
+    } err]} {
+	error_popup "Error creating tag: $err"
+	return
+    }
+
+    set tagids($tag) $id
+    lappend idtags($id) $tag
+    $canv delete tag.$id
+    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
+    }
+}
+
+proc mktagcan {} {
+    global mktagtop
+
+    catch {destroy $mktagtop}
+    unset mktagtop
+}
+
+proc mktaggo {} {
+    domktag
+    mktagcan
+}
+
+proc writecommit {} {
+    global rowmenuid wrcomtop commitinfo wrcomcmd
+
+    set top .writecommit
+    set wrcomtop $top
+    catch {destroy $top}
+    toplevel $top
+    label $top.title -text "Write commit to file"
+    grid $top.title - -pady 10
+    label $top.id -text "ID:"
+    entry $top.sha1 -width 40 -relief flat
+    $top.sha1 insert 0 $rowmenuid
+    $top.sha1 conf -state readonly
+    grid $top.id $top.sha1 -sticky w
+    entry $top.head -width 60 -relief flat
+    $top.head insert 0 [lindex $commitinfo($rowmenuid) 0]
+    $top.head conf -state readonly
+    grid x $top.head -sticky w
+    label $top.clab -text "Command:"
+    entry $top.cmd -width 60 -textvariable wrcomcmd
+    grid $top.clab $top.cmd -sticky w -pady 10
+    label $top.flab -text "Output file:"
+    entry $top.fname -width 60
+    $top.fname insert 0 [file normalize "commit-[string range $rowmenuid 0 6]"]
+    grid $top.flab $top.fname -sticky w
+    frame $top.buts
+    button $top.buts.gen -text "Write" -command wrcomgo
+    button $top.buts.can -text "Cancel" -command wrcomcan
+    grid $top.buts.gen $top.buts.can
+    grid columnconfigure $top.buts 0 -weight 1 -uniform a
+    grid columnconfigure $top.buts 1 -weight 1 -uniform a
+    grid $top.buts - -pady 10 -sticky ew
+    focus $top.fname
+}
+
+proc wrcomgo {} {
+    global wrcomtop
+
+    set id [$wrcomtop.sha1 get]
+    set cmd "echo $id | [$wrcomtop.cmd get]"
+    set fname [$wrcomtop.fname get]
+    if {[catch {exec sh -c $cmd >$fname &} err]} {
+	error_popup "Error writing commit: $err"
+    }
+    catch {destroy $wrcomtop}
+    unset wrcomtop
+}
+
+proc wrcomcan {} {
+    global wrcomtop
+
+    catch {destroy $wrcomtop}
+    unset wrcomtop
 }
 
 proc doquit {} {
@@ -1796,9 +2931,12 @@ proc doquit {} {
 set datemode 0
 set boldnames 0
 set diffopts "-U 5 -p"
+set wrcomcmd "git-diff-tree --stdin -p --pretty"
 
 set mainfont {Helvetica 9}
 set textfont {Courier 9}
+set findmergefiles 0
+set gaudydiff 0
 
 set colors {green red blue magenta darkgrey brown orange}
 
@@ -1824,6 +2962,7 @@ foreach arg $argv {
 set stopped 0
 set redisplaying 0
 set stuffsaved 0
+set patchnum 0
 setcoords
 makewindow
 readrefs