From dbe2c0a068fb0eda9b225f51b1df785d6f076de5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Ekl=C3=B6f?= <daniel@ekloef.se>
Date: Mon, 13 Jun 2022 11:41:54 +0200
Subject: [PATCH] selection: allow HT, VT and FF, disallow NUL in non-bracketed
 paste mode
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This syncs foot with more recent versions of XTerm, where it’s
“disallowedPasteControls” resource has changed its default value to

  BS,DEL,ENQ,EOT,ESC,NULL

Note that we’re already stripping out ENQ,EOT,ESC in all modes.

What does it mean for foot:

* HT, VT and FF are now allowed, regardless of paste mode
* NUL is now stripped in non-bracketed paste mode

Closes #1084
---
 CHANGELOG.md |  6 ++++++
 selection.c  | 19 ++++++++++++++++---
 2 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 537a70d2..5ff030d5 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -57,6 +57,12 @@
 
 * Use `$HOME` instead of `getpwuid()` to retrieve the user’s home
   directory when searching for `foot.ini`.
+* HT, VT and FF are no longer stripped when pasting in non-bracketed
+  mode ([#1084][1084]).
+* NUL is now stripped when pasting in non-bracketed mode
+  ([#1084][1084]).
+
+[1084]: https://codeberg.org/dnkl/foot/issues/1084
 
 
 ### Deprecated
diff --git a/selection.c b/selection.c
index 6b57f48c..37dd2c8d 100644
--- a/selection.c
+++ b/selection.c
@@ -1845,9 +1845,22 @@ fdm_receive(struct fdm *fdm, int fd, int events, void *data)
                 skip_one();
                 goto again;
 
-            /* Additional control characters stripped by default (but
-             * configurable) in XTerm: BS, HT, DEL */
-            case '\b': case '\t': case '\v': case '\f': case '\x7f':
+            /*
+             * In addition to stripping non-formatting C0 controls,
+             * XTerm has an option, “disallowedPasteControls”, that
+             * defines C0 controls that will be replaced with spaces
+             * when pasted.
+             *
+             * It’s default value is BS,DEL,ENQ,EOT,NUL
+             *
+             * Instead of replacing them with spaces, we allow them in
+             * bracketed paste mode, and strip them completely in
+             * non-bracketed mode.
+             *
+             * Note some of the (default) XTerm controls are already
+             * handled above.
+             */
+            case '\b': case '\x7f': case '\x00':
                 if (!ctx->bracketed) {
                     skip_one();
                     goto again;