gitk: Fix bugs in the Find function

This fixes the problem reported by Brian Downing where searching for
a string that doesn't exist would give a Tcl error.  The basic problem
was that we weren't reading the data for the last commit since it
wasn't terminated with a null.  This effectively adds a null on the end
(if there isn't one already) to make sure we process the last commit.

This also makes the yellow background behind instances of the search
string appear more consistently, and fixes a bug where the "/" key
would just find the same commit again and again instead of advancing.

Signed-off-by: Paul Mackerras <paulus@samba.org>

gitk

@@ -139,6 +139,10 @@ proc getcommitlines {fd view}  {
     global vparentlist vdisporder vcmitlisted
 
     set stuff [read $fd 500000]
+    # git log doesn't terminate the last commit with a null...
+    if {$stuff == {} && $leftover($view) ne {} && [eof $fd]} {
+	set stuff "\0"
+    }
     if {$stuff == {}} {
 	if {![eof $fd]} {
 	    return 1
@@ -2157,7 +2161,7 @@ proc readfhighlight {} {
 
 proc find_change {name ix op} {
     global nhighlights mainfont boldnamerows
-    global findstring findpattern findtype markingmatches
+    global findstring findpattern findtype
 
     # delete previous highlights, if any
     foreach row $boldnamerows {
@@ -2172,7 +2176,6 @@ proc find_change {name ix op} {
 		   $findstring]
 	set findpattern "*$e*"
     }
-    set markingmatches [expr {$findstring ne {}}]
     drawvisible
 }
 
@@ -2218,26 +2221,32 @@ proc askfindhighlight {row id} {
 	    }
 	}
 	if {$markingmatches} {
-	    markrowmatches $row [lindex $info 0] [lindex $info 1]
+	    markrowmatches $row $id
 	}
     }
     set nhighlights($row) $isbold
 }
 
-proc markrowmatches {row headline author} {
-    global canv canv2 linehtag linentag
+proc markrowmatches {row id} {
+    global canv canv2 linehtag linentag commitinfo findloc
 
+    set headline [lindex $commitinfo($id) 0]
+    set author [lindex $commitinfo($id) 1]
     $canv delete match$row
     $canv2 delete match$row
-    set m [findmatches $headline]
-    if {$m ne {}} {
-	markmatches $canv $row $headline $linehtag($row) $m \
-	    [$canv itemcget $linehtag($row) -font]
+    if {$findloc eq "All fields" || $findloc eq "Headline"} {
+	set m [findmatches $headline]
+	if {$m ne {}} {
+	    markmatches $canv $row $headline $linehtag($row) $m \
+		[$canv itemcget $linehtag($row) -font] $row
+	}
     }
-    set m [findmatches $author]
-    if {$m ne {}} {
-	markmatches $canv2 $row $author $linentag($row) $m \
-	    [$canv2 itemcget $linentag($row) -font]
+    if {$findloc eq "All fields" || $findloc eq "Author"} {
+	set m [findmatches $author]
+	if {$m ne {}} {
+	    markmatches $canv2 $row $author $linentag($row) $m \
+		[$canv2 itemcget $linentag($row) -font] $row
+	}
     }
 }
 
@@ -3406,7 +3415,7 @@ proc drawcmittext {id row col} {
     global linespc canv canv2 canv3 canvy0 fgcolor curview
     global commitlisted commitinfo rowidlist parentlist
     global rowtextx idpos idtags idheads idotherrefs
-    global linehtag linentag linedtag markingmatches
+    global linehtag linentag linedtag
     global mainfont canvxmax boldrows boldnamerows fgcolor nullid nullid2
 
     # listed is 0 for boundary, 1 for normal, 2 for left, 3 for right
@@ -3483,9 +3492,6 @@ proc drawcmittext {id row col} {
     set linedtag($row) [$canv3 create text 3 $y -anchor w -fill $fgcolor \
 			    -text $date -font $mainfont -tags text]
     set xr [expr {$xt + [font measure $mainfont $headline]}]
-    if {$markingmatches} {
-	markrowmatches $row $headline $name
-    }
     if {$xr > $canvxmax} {
 	set canvxmax $xr
 	setcanvscroll
@@ -3494,7 +3500,7 @@ proc drawcmittext {id row col} {
 
 proc drawcmitrow {row} {
     global displayorder rowidlist
-    global iddrawn
+    global iddrawn markingmatches
     global commitinfo parentlist numcommits
     global filehighlight fhighlights findstring nhighlights
     global hlview vhighlights
@@ -3515,18 +3521,22 @@ proc drawcmitrow {row} {
     if {$highlight_related ne "None" && ![info exists rhighlights($row)]} {
 	askrelhighlight $row $id
     }
-    if {[info exists iddrawn($id)]} return
-    set col [lsearch -exact [lindex $rowidlist $row] $id]
-    if {$col < 0} {
-	puts "oops, row $row id $id not in list"
-	return
+    if {![info exists iddrawn($id)]} {
+	set col [lsearch -exact [lindex $rowidlist $row] $id]
+	if {$col < 0} {
+	    puts "oops, row $row id $id not in list"
+	    return
+	}
+	if {![info exists commitinfo($id)]} {
+	    getcommit $id
+	}
+	assigncolor $id
+	drawcmittext $id $row $col
+	set iddrawn($id) 1
     }
-    if {![info exists commitinfo($id)]} {
-	getcommit $id
+    if {$markingmatches} {
+	markrowmatches $row $id
     }
-    assigncolor $id
-    drawcmittext $id $row $col
-    set iddrawn($id) 1
 }
 
 proc drawcommits {row {endrow {}}} {
@@ -4044,7 +4054,6 @@ proc dofind {{rev 0}} {
     if {!$rev} {
 	run findmore
     } else {
-	set findcurline $findstartline
 	if {$findcurline == 0} {
 	    set findcurline $numcommits
 	}
@@ -4079,7 +4088,7 @@ proc findprev {} {
 
 proc findmore {} {
     global commitdata commitinfo numcommits findstring findpattern findloc
-    global findstartline findcurline markingmatches displayorder
+    global findstartline findcurline displayorder
 
     set fldtypes {Headline Author Date Committer CDate Comments}
     set l [expr {$findcurline + 1}]
@@ -4097,6 +4106,8 @@ proc findmore {} {
     set last 0
     for {} {$l < $lim} {incr l} {
 	set id [lindex $displayorder $l]
+	# shouldn't happen unless git log doesn't give all the commits...
+	if {![info exists commitdata($id)]} continue
 	if {![doesmatch $commitdata($id)]} continue
 	if {![info exists commitinfo($id)]} {
 	    getcommit $id
@@ -4105,7 +4116,6 @@ proc findmore {} {
 	foreach f $info ty $fldtypes {
 	    if {($findloc eq "All fields" || $findloc eq $ty) &&
 		[doesmatch $f]} {
-		set markingmatches 1
 		findselectline $l
 		notbusy finding
 		return 0
@@ -4124,7 +4134,7 @@ proc findmore {} {
 
 proc findmorerev {} {
     global commitdata commitinfo numcommits findstring findpattern findloc
-    global findstartline findcurline markingmatches displayorder
+    global findstartline findcurline displayorder
 
     set fldtypes {Headline Author Date Committer CDate Comments}
     set l $findcurline
@@ -4151,7 +4161,6 @@ proc findmorerev {} {
 	foreach f $info ty $fldtypes {
 	    if {($findloc eq "All fields" || $findloc eq $ty) &&
 		[doesmatch $f]} {
-		set markingmatches 1
 		findselectline $l
 		notbusy finding
 		return 0
@@ -4169,7 +4178,10 @@ proc findmorerev {} {
 }
 
 proc findselectline {l} {
-    global findloc commentend ctext
+    global findloc commentend ctext findcurline markingmatches
+
+    set markingmatches 1
+    set findcurline $l
     selectline $l 1
     if {$findloc == "All fields" || $findloc == "Comments"} {
 	# highlight the matches in the comments
@@ -4181,10 +4193,13 @@ proc findselectline {l} {
 	    $ctext tag add found "1.0 + $start c" "1.0 + $end c"
 	}
     }
+    drawvisible
 }
 
 # mark the bits of a headline or author that match a find string
-proc markmatches {canv l str tag matches font} {
+proc markmatches {canv l str tag matches font row} {
+    global selectedline
+
     set bbox [$canv bbox $tag]
     set x0 [lindex $bbox 0]
     set y0 [lindex $bbox 1]
@@ -4199,6 +4214,9 @@ proc markmatches {canv l str tag matches font} {
 		   [expr {$x0+$xlen+2}] $y1 \
 		   -outline {} -tags [list match$l matches] -fill yellow]
 	$canv lower $t
+	if {[info exists selectedline] && $row == $selectedline} {
+	    $canv raise $t secsel
+	}
     }
 }