From bb5cb23daf751790950ff9f761f8884e21c88d00 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Tue, 24 Jan 2023 11:23:16 +0000
Subject: [PATCH 1/2] gitk: prevent overly long command lines

To avoid running into command line limitations, some of Git's commands
support the `--stdin` option.

Let's use exactly this option in the three rev-list/log invocations in
gitk that would otherwise possibly run the danger of trying to invoke a
too-long command line.

While it is easy to redirect either stdin or stdout in Tcl/Tk scripts,
what we need here is both. We need to capture the output, yet we also
need to pipe in the revs/files arguments via stdin (because stdin does
not have any limit, unlike the command line). To help this, we use the
neat Tcl feature where you can capture stdout and at the same time feed
a fixed string as stdin to the spawned process.

One non-obvious aspect about this change is that the `--stdin` option
allows to specify revs, the double-dash, and files, but *no* other
options such as `--not`. This is addressed by prefixing the "negative"
revs with `^` explicitly rather than relying on the `--not` option
(thanks for coming up with that idea, Max!).

This fixes https://github.com/git-for-windows/git/issues/1987

Analysis-and-initial-patch-by: Max Kirillov <max@max630.net>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 gitk | 24 +++++++++++++++++++-----
 1 file changed, 19 insertions(+), 5 deletions(-)

diff --git a/gitk b/gitk
index 0ae7d68590..92375ca6a2 100755
--- a/gitk
+++ b/gitk
@@ -405,14 +405,16 @@ proc start_rev_list {view} {
         if {$revs eq {}} {
             return 0
         }
-        set args [concat $vflags($view) $revs]
+        set args $vflags($view)
     } else {
+        set revs {}
         set args $vorigargs($view)
     }
 
     if {[catch {
         set fd [open [concat | git log --no-color -z --pretty=raw $show_notes \
-                        --parents --boundary $args "--" $files] r]
+                        --parents --boundary $args --stdin \
+                        "<<[join [concat $revs "--" $files] "\\n"]"] r]
     } err]} {
         error_popup "[mc "Error executing git log:"] $err"
         return 0
@@ -554,13 +556,19 @@ proc updatecommits {} {
             set revs $newrevs
             set vposids($view) [lsort -unique [concat $oldpos $vposids($view)]]
         }
-        set args [concat $vflags($view) $revs --not $oldpos]
+        set args $vflags($view)
+        foreach r $oldpos {
+                lappend revs "^$r"
+        }
     } else {
+        set revs {}
         set args $vorigargs($view)
     }
     if {[catch {
         set fd [open [concat | git log --no-color -z --pretty=raw $show_notes \
-                        --parents --boundary $args "--" $vfilelimit($view)] r]
+                        --parents --boundary $args --stdin \
+                        "<<[join [concat $revs "--" \
+                                $vfilelimit($view)] "\\n"]"] r]
     } err]} {
         error_popup "[mc "Error executing git log:"] $err"
         return
@@ -10231,10 +10239,16 @@ proc getallcommits {} {
             foreach id $seeds {
                 lappend ids "^$id"
             }
+            lappend ids "--"
         }
     }
     if {$ids ne {}} {
-        set fd [open [concat $cmd $ids] r]
+        if {$ids eq "--all"} {
+            set cmd [concat $cmd "--all"]
+        } else {
+            set cmd [concat $cmd --stdin "<<[join $ids "\\n"]"]
+        }
+        set fd [open $cmd r]
         fconfigure $fd -blocking 0
         incr allcommits
         nowbusy allcommits

From 7dd272eca153058da2e8d5b9960bbbf0b4f0cbaa Mon Sep 17 00:00:00 2001
From: Nico Rieck <nico.rieck@gmail.com>
Date: Tue, 24 Jan 2023 11:23:17 +0000
Subject: [PATCH 2/2] gitk: escape file paths before piping to git log

We just started piping the file paths via `stdin` instead of passing
them via the command-line, to avoid running into command-line
limitations.

However, since we now pipe the file paths, we need to take care of
special characters.

This fixes https://github.com/git-for-windows/git/issues/2293

Signed-off-by: Nico Rieck <nico.rieck@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 gitk | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/gitk b/gitk
index 92375ca6a2..df3ba2ea99 100755
--- a/gitk
+++ b/gitk
@@ -353,6 +353,16 @@ proc parseviewrevs {view revs} {
     return $ret
 }
 
+# Escapes a list of filter paths to be passed to git log via stdin. Note that
+# paths must not be quoted.
+proc escape_filter_paths {paths} {
+	set escaped [list]
+	foreach path $paths {
+		lappend escaped [string map {\\ \\\\ "\ " "\\\ "} $path]
+	}
+	return $escaped
+}
+
 # Start off a git log process and arrange to read its output
 proc start_rev_list {view} {
     global startmsecs commitidx viewcomplete curview
@@ -414,7 +424,8 @@ proc start_rev_list {view} {
     if {[catch {
         set fd [open [concat | git log --no-color -z --pretty=raw $show_notes \
                         --parents --boundary $args --stdin \
-                        "<<[join [concat $revs "--" $files] "\\n"]"] r]
+                        "<<[join [concat $revs "--" \
+                                [escape_filter_paths $files]] "\\n"]"] r]
     } err]} {
         error_popup "[mc "Error executing git log:"] $err"
         return 0
@@ -568,7 +579,8 @@ proc updatecommits {} {
         set fd [open [concat | git log --no-color -z --pretty=raw $show_notes \
                         --parents --boundary $args --stdin \
                         "<<[join [concat $revs "--" \
-                                $vfilelimit($view)] "\\n"]"] r]
+                                [escape_filter_paths \
+                                        $vfilelimit($view)]] "\\n"]"] r]
     } err]} {
         error_popup "[mc "Error executing git log:"] $err"
         return