51215: consume whole CSI sequences from the input

This affects CSI sequences that aren't explicitly bound but arrive
within the usual KEYTIMEOUT time limits. A single undefined-key widget
is run instead of unintended bindings for Escape and other characters in
the sequence.

4 files changed, 60 insertions, 2 deletions

diff --git a/ChangeLog b/ChangeLog
index acde99fb4..e9e572957 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2022-12-16  Oliver Kiddle  <opk@zsh.org>
+
+	* 51215: Src/Zle/zle_keymap.c, Test/X03zlebindkey.ztst,
+	Test/X02zlevi.ztst: consume whole CSI sequences from the input
+	even where they aren't explicitly bound
+
 2022-12-15  Daniel Shahaf  <d.s@daniel.shahaf.name>
 
 	* unposted: Src/zsh.h: Follow-up to the last commit: Fix a typo
diff --git a/Src/Zle/zle_keymap.c b/Src/Zle/zle_keymap.c
index d90838f03..48691e8d0 100644
--- a/Src/Zle/zle_keymap.c
+++ b/Src/Zle/zle_keymap.c
@@ -1586,7 +1586,7 @@ getkeymapcmd(Keymap km, Thingy *funcp, char **strp)
     Thingy func = t_undefinedkey;
     char *str = NULL;
     int lastlen = 0, lastc = lastchar;
-    int timeout = 0;
+    int timeout = 0, csi = 0, startcsi;
 
     keybuflen = 0;
     keybuf[0] = 0;
@@ -1636,7 +1636,30 @@ getkeymapcmd(Keymap km, Thingy *funcp, char **strp)
 	    }
 #endif
 	}
-	if (!ispfx)
+
+	/* CSI key sequences have a well defined structure so if we currently
+	 * have an incomplete one, loop so the rest of it will be included in
+	 * the key sequence if that arrives within the timeout. */
+	if (keybuflen >= 3 && !csi) {
+	    startcsi = keybuflen - 3;
+	    csi = keybuf[startcsi] == '\033' && keybuf[keybuflen - 2] == '[';
+	}
+	if (csi) {
+	    csi = keybuf[keybuflen - 2] != Meta && keybuf[keybuflen - 1] >= 0x20
+		&& keybuf[keybuflen - 1] <= 0x3f;
+	    /* If we reach the end of a valid CSI sequence and the matched key
+	     * binding is for part of the CSI introduction, select instead the
+	     * undefined-key widget and consume the full sequence from the
+	     * input buffer. */
+	    if (!csi && keybuf[keybuflen - 1] >= 0x40 &&
+		    keybuf[keybuflen - 1] <= 0x7e && lastlen > startcsi &&
+		    lastlen <= startcsi + 2) {
+		func = t_undefinedkey;
+		lastlen = keybuflen;
+	    }
+	}
+
+	if (!ispfx && !csi)
 	    break;
     }
     if(!lastlen && keybuflen)
diff --git a/Test/X02zlevi.ztst b/Test/X02zlevi.ztst
index 203c13c32..ccfb7b1c6 100644
--- a/Test/X02zlevi.ztst
+++ b/Test/X02zlevi.ztst
@@ -596,6 +596,13 @@
 >BUFFER: 1ls `2`  $(3) "4" $'5' ${6}
 >CURSOR: 0
 
+  zpty_run 'bindkey -s -a "cw" "dwi"'
+  zletest $'one two\e0cwyksi'
+  zpty_run 'bindkey -r -a "cw"'
+0:for a vi command, wait to allow a longer binding to be used
+>BUFFER: yksitwo
+>CURSOR: 4
+
 %clean
 
   zmodload -ui zsh/zpty
diff --git a/Test/X03zlebindkey.ztst b/Test/X03zlebindkey.ztst
index 5277332a7..1b63b3920 100644
--- a/Test/X03zlebindkey.ztst
+++ b/Test/X03zlebindkey.ztst
@@ -37,6 +37,28 @@
 >"^Xy" "bar"
 >"^Xy" undefined-key
 
+  zpty_run 'bindkey -s "\e[" altbracket'
+  zletest $'$\C-A\e[17~'
+  zpty_run 'bindkey -r "\e["'
+0:binding to CSI introduction is not used if a full sequence arrives
+>BUFFER: $
+>CURSOR: 0
+
+  zpty_run 'bindkey -s "\e[1" altbracketone'
+  zletest $'$\C-A\e[17~'
+  zpty_run 'bindkey -r "\e[1"'
+0:binding to longer prefix of a CSI sequence is used
+# we assume the user knows what they're doing
+>BUFFER: altbracketone7~$
+>CURSOR: 15
+
+  zpty_run 'bindkey -s "\e[" altbracket'
+  zletest $'$\C-A\e[177'
+  zpty_run 'bindkey -r "\e["'
+0:use prefix binding where we don't have a CSI sequence
+>BUFFER: altbracket177$
+>CURSOR: 13
+
 # As we're only looking at definitions here, we don't
 # bother using the pseudo-terminal; just test in the normal fashion.
   bindkey -e