[dwm][keychord] fix event loss in chord wait loop, rebase onto 6.8 - sites - public wiki contents of suckless.org
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DIR commit c690081873592d6067ca72ae1ec40d761b304a9d
DIR parent b0c6ea10c2ffa564d9e1bd159343fae89efe4b51
HTML Author: Lukasz Kasprzak <lukas@labunix.xyz>
Date: Fri, 17 Jul 2026 16:03:04 +0200
[dwm][keychord] fix event loss in chord wait loop, rebase onto 6.8
While waiting for the next key of a chord, keypress() discarded every event
that was not a KeyPress. Discarding a ButtonPress that activated the
GrabModeSync passive grab from grabbuttons() left pointer and keyboard frozen
permanently: only buttonpress()'s XAllowEvents can release that grab, and the
loop could never exit, because a frozen keyboard cannot deliver the KeyPress it
waits for. Only killing dwm ended it. A MapRequest arriving mid-chord was
dropped the same way, leaving the window unmanaged.
Reproduced on Xephyr with stock dwm 6.8 + dwm-keychord-6.4.diff and its default
config: press the Mod+e prefix, click any unfocused client, and the session
freezes (XGrabKeyboard -> GrabFrozen, Button1 held). Healthy with this patch.
Events are now dispatched through handler[] as run() does, breaking on KeyPress
before dispatch so keypress() cannot recurse.
Also rebased onto dwm 6.8 and noted that dwm-keychord-6.4.diff applies to
6.5-6.8 rather than 6.4: grabkeys() switched to XDisplayKeycodes in 89f9905,
which is in 6.5 but not 6.4.
Original keychord patch by Hai Nguyen, updated for newer grabkeys() by
Aaron Zueger; both kept as authors.
Diffstat:
A dwm.suckless.org/patches/keychord/… | 272 +++++++++++++++++++++++++++++++
M dwm.suckless.org/patches/keychord/… | 14 +++++++++++++-
2 files changed, 285 insertions(+), 1 deletion(-)
---
DIR diff --git a/dwm.suckless.org/patches/keychord/dwm-keychord-20260717-f63cde9.diff b/dwm.suckless.org/patches/keychord/dwm-keychord-20260717-f63cde9.diff
@@ -0,0 +1,272 @@
+From 9c020a20a2e1091e8b47edfea5e8795d8b451bc9 Mon Sep 17 00:00:00 2001
+From: Lukasz Kasprzak <lukas@labunix.xyz>
+Date: Fri, 17 Jul 2026 15:45:22 +0200
+Subject: [PATCH] keychord: bind a sequence of keys, and dispatch events while
+ waiting
+
+Original keychord patch by Hai Nguyen <hhai2105@gmail.com>, updated for
+dwm 6.4+ grabkeys() by Aaron Zueger <contact@azureorange.xyz>. This
+revision rebases onto dwm 6.8 and fixes an event-loss bug in the chord
+wait loop.
+
+The wait loop used to discard every event that was not a KeyPress:
+
+ while (running && !XNextEvent(dpy, &event) && !ran)
+ if(event.type == KeyPress)
+ break;
+
+Two consequences, both reproduced on Xephyr:
+
+1. Unrecoverable input freeze. grabbuttons() grabs unfocused clients
+ GrabModeSync/GrabModeSync, so clicking one freezes pointer AND
+ keyboard until the grabbing client calls XAllowEvents. dwm does that
+ in buttonpress() -- but if the ButtonPress is discarded here,
+ buttonpress() never runs. The grab stays frozen forever and the loop
+ can never exit, because a frozen keyboard cannot deliver the KeyPress
+ it is waiting for. Only killing dwm ends it; XSendEvent is discarded
+ by this same loop and XTEST queues behind the frozen device.
+ Repro: press a chord prefix, then click any unfocused client.
+ Observed: XGrabKeyboard -> GrabFrozen, XQueryPointer -> Button1 held.
+
+2. Orphaned windows. A MapRequest arriving mid-chord is dropped, so a
+ window opening during a chord is never managed. DestroyNotify,
+ Expose and ConfigureRequest are lost the same way.
+
+Dispatch through handler[] as run() does, breaking on KeyPress before
+dispatch so keypress() cannot recurse. The `&& !ran` term is dropped:
+ran is always 0 on entry and nothing in the body can set it.
+---
+ config.def.h | 81 ++++++++++++++++++++++++++--------------------------
+ dwm.c | 79 +++++++++++++++++++++++++++++++++++++++++---------
+ 2 files changed, 106 insertions(+), 54 deletions(-)
+
+diff --git a/config.def.h b/config.def.h
+index 81c3fc0..7c7ec36 100644
+--- a/config.def.h
++++ b/config.def.h
+@@ -47,11 +47,11 @@ static const Layout layouts[] = {
+
+ /* key definitions */
+ #define MODKEY Mod1Mask
+-#define TAGKEYS(KEY,TAG) \
+- { MODKEY, KEY, view, {.ui = 1 << TAG} }, \
+- { MODKEY|ControlMask, KEY, toggleview, {.ui = 1 << TAG} }, \
+- { MODKEY|ShiftMask, KEY, tag, {.ui = 1 << TAG} }, \
+- { MODKEY|ControlMask|ShiftMask, KEY, toggletag, {.ui = 1 << TAG} },
++#define TAGKEYS(KEY,TAG) \
++ &((Keychord){1, {{MODKEY, KEY}}, view, {.ui = 1 << TAG} }), \
++ &((Keychord){1, {{MODKEY|ControlMask, KEY}}, toggleview, {.ui = 1 << TAG} }), \
++ &((Keychord){1, {{MODKEY|ShiftMask, KEY}}, tag, {.ui = 1 << TAG} }), \
++ &((Keychord){1, {{MODKEY|ControlMask|ShiftMask, KEY}}, toggletag, {.ui = 1 << TAG} }),
+
+ /* helper for spawning shell commands in the pre dwm-5.0 fashion */
+ #define SHCMD(cmd) { .v = (const char*[]){ "/bin/sh", "-c", cmd, NULL } }
+@@ -61,41 +61,42 @@ static char dmenumon[2] = "0"; /* component of dmenucmd, manipulated in spawn()
+ static const char *dmenucmd[] = { "dmenu_run", "-m", dmenumon, "-fn", dmenufont, "-nb", col_gray1, "-nf", col_gray3, "-sb", col_cyan, "-sf", col_gray4, NULL };
+ static const char *termcmd[] = { "st", NULL };
+
+-static const Key keys[] = {
+- /* modifier key function argument */
+- { MODKEY, XK_p, spawn, {.v = dmenucmd } },
+- { MODKEY|ShiftMask, XK_Return, spawn, {.v = termcmd } },
+- { MODKEY, XK_b, togglebar, {0} },
+- { MODKEY, XK_j, focusstack, {.i = +1 } },
+- { MODKEY, XK_k, focusstack, {.i = -1 } },
+- { MODKEY, XK_i, incnmaster, {.i = +1 } },
+- { MODKEY, XK_d, incnmaster, {.i = -1 } },
+- { MODKEY, XK_h, setmfact, {.f = -0.05} },
+- { MODKEY, XK_l, setmfact, {.f = +0.05} },
+- { MODKEY, XK_Return, zoom, {0} },
+- { MODKEY, XK_Tab, view, {0} },
+- { MODKEY|ShiftMask, XK_c, killclient, {0} },
+- { MODKEY, XK_t, setlayout, {.v = &layouts[0]} },
+- { MODKEY, XK_f, setlayout, {.v = &layouts[1]} },
+- { MODKEY, XK_m, setlayout, {.v = &layouts[2]} },
+- { MODKEY, XK_space, setlayout, {0} },
+- { MODKEY|ShiftMask, XK_space, togglefloating, {0} },
+- { MODKEY, XK_0, view, {.ui = ~0 } },
+- { MODKEY|ShiftMask, XK_0, tag, {.ui = ~0 } },
+- { MODKEY, XK_comma, focusmon, {.i = -1 } },
+- { MODKEY, XK_period, focusmon, {.i = +1 } },
+- { MODKEY|ShiftMask, XK_comma, tagmon, {.i = -1 } },
+- { MODKEY|ShiftMask, XK_period, tagmon, {.i = +1 } },
+- TAGKEYS( XK_1, 0)
+- TAGKEYS( XK_2, 1)
+- TAGKEYS( XK_3, 2)
+- TAGKEYS( XK_4, 3)
+- TAGKEYS( XK_5, 4)
+- TAGKEYS( XK_6, 5)
+- TAGKEYS( XK_7, 6)
+- TAGKEYS( XK_8, 7)
+- TAGKEYS( XK_9, 8)
+- { MODKEY|ShiftMask, XK_q, quit, {0} },
++static Keychord *keychords[] = {
++ /* Keys function argument */
++ &((Keychord){1, {{MODKEY, XK_p}}, spawn, {.v = dmenucmd } }),
++ &((Keychord){1, {{MODKEY|ShiftMask, XK_Return}}, spawn, {.v = termcmd } }),
++ &((Keychord){2, {{MODKEY, XK_e}, {MODKEY, XK_e}}, spawn, {.v = termcmd } }),
++ &((Keychord){1, {{MODKEY, XK_b}}, togglebar, {0} }),
++ &((Keychord){1, {{MODKEY, XK_j}}, focusstack, {.i = +1 } }),
++ &((Keychord){1, {{MODKEY, XK_k}}, focusstack, {.i = -1 } }),
++ &((Keychord){1, {{MODKEY, XK_i}}, incnmaster, {.i = +1 } }),
++ &((Keychord){1, {{MODKEY, XK_d}}, incnmaster, {.i = -1 } }),
++ &((Keychord){1, {{MODKEY, XK_h}}, setmfact, {.f = -0.05} }),
++ &((Keychord){1, {{MODKEY, XK_l}}, setmfact, {.f = +0.05} }),
++ &((Keychord){1, {{MODKEY, XK_Return}}, zoom, {0} }),
++ &((Keychord){1, {{MODKEY, XK_Tab}}, view, {0} }),
++ &((Keychord){1, {{MODKEY|ShiftMask, XK_c}}, killclient, {0} }),
++ &((Keychord){1, {{MODKEY, XK_t}}, setlayout, {.v = &layouts[0]} }),
++ &((Keychord){1, {{MODKEY, XK_f}}, setlayout, {.v = &layouts[1]} }),
++ &((Keychord){1, {{MODKEY, XK_m}}, setlayout, {.v = &layouts[2]} }),
++ &((Keychord){1, {{MODKEY, XK_space}}, setlayout, {0} }),
++ &((Keychord){1, {{MODKEY|ShiftMask, XK_space}}, togglefloating, {0} }),
++ &((Keychord){1, {{MODKEY, XK_0}}, view, {.ui = ~0 } }),
++ &((Keychord){1, {{MODKEY|ShiftMask, XK_0}}, tag, {.ui = ~0 } }),
++ &((Keychord){1, {{MODKEY, XK_comma}}, focusmon, {.i = -1 } }),
++ &((Keychord){1, {{MODKEY, XK_period}}, focusmon, {.i = +1 } }),
++ &((Keychord){1, {{MODKEY|ShiftMask, XK_comma}}, tagmon, {.i = -1 } }),
++ &((Keychord){1, {{MODKEY|ShiftMask, XK_period}}, tagmon, {.i = +1 } }),
++ &((Keychord){1, {{MODKEY|ShiftMask, XK_q}}, quit, {0} }),
++ TAGKEYS( XK_1, 0)
++ TAGKEYS( XK_2, 1)
++ TAGKEYS( XK_3, 2)
++ TAGKEYS( XK_4, 3)
++ TAGKEYS( XK_5, 4)
++ TAGKEYS( XK_6, 5)
++ TAGKEYS( XK_7, 6)
++ TAGKEYS( XK_8, 7)
++ TAGKEYS( XK_9, 8)
+ };
+
+ /* button definitions */
+diff --git a/dwm.c b/dwm.c
+index 53b393e..243b12c 100644
+--- a/dwm.c
++++ b/dwm.c
+@@ -101,9 +101,14 @@ struct Client {
+ typedef struct {
+ unsigned int mod;
+ KeySym keysym;
++} Key;
++
++typedef struct {
++ unsigned int n;
++ const Key keys[5];
+ void (*func)(const Arg *);
+ const Arg arg;
+-} Key;
++} Keychord;
+
+ typedef struct {
+ const char *symbol;
+@@ -266,6 +271,7 @@ static Display *dpy;
+ static Drw *drw;
+ static Monitor *mons, *selmon;
+ static Window root, wmcheckwin;
++unsigned int currentkey = 0;
+
+ /* configuration, allows nested code to access above variables */
+ #include "config.h"
+@@ -954,7 +960,8 @@ grabkeys(void)
+ {
+ updatenumlockmask();
+ {
+- unsigned int i, j, k;
++ /* unsigned int i, j, k; */
++ unsigned int i, c, k;
+ unsigned int modifiers[] = { 0, LockMask, numlockmask, numlockmask|LockMask };
+ int start, end, skip;
+ KeySym *syms;
+@@ -964,15 +971,18 @@ grabkeys(void)
+ syms = XGetKeyboardMapping(dpy, start, end - start + 1, &skip);
+ if (!syms)
+ return;
++
+ for (k = start; k <= end; k++)
+- for (i = 0; i < LENGTH(keys); i++)
++ for (i = 0; i < LENGTH(keychords); i++)
+ /* skip modifier codes, we do that ourselves */
+- if (keys[i].keysym == syms[(k - start) * skip])
+- for (j = 0; j < LENGTH(modifiers); j++)
++ if (keychords[i]->keys[currentkey].keysym == syms[(k - start) * skip])
++ for (c = 0; c < LENGTH(modifiers); c++)
+ XGrabKey(dpy, k,
+- keys[i].mod | modifiers[j],
++ keychords[i]->keys[currentkey].mod | modifiers[c],
+ root, True,
+ GrabModeAsync, GrabModeAsync);
++ if(currentkey > 0)
++ XGrabKey(dpy, XKeysymToKeycode(dpy, XK_Escape), AnyModifier, root, True, GrabModeAsync, GrabModeAsync);
+ XFree(syms);
+ }
+ }
+@@ -999,17 +1009,58 @@ isuniquegeom(XineramaScreenInfo *unique, size_t n, XineramaScreenInfo *info)
+ void
+ keypress(XEvent *e)
+ {
+- unsigned int i;
++ /* unsigned int i; */
++ XEvent event = *e;
++ unsigned int ran = 0;
+ KeySym keysym;
+ XKeyEvent *ev;
+
+- ev = &e->xkey;
+- keysym = XKeycodeToKeysym(dpy, (KeyCode)ev->keycode, 0);
+- for (i = 0; i < LENGTH(keys); i++)
+- if (keysym == keys[i].keysym
+- && CLEANMASK(keys[i].mod) == CLEANMASK(ev->state)
+- && keys[i].func)
+- keys[i].func(&(keys[i].arg));
++ Keychord *arr1[sizeof(keychords) / sizeof(Keychord*)];
++ Keychord *arr2[sizeof(keychords) / sizeof(Keychord*)];
++ memcpy(arr1, keychords, sizeof(keychords));
++ Keychord **rpointer = arr1;
++ Keychord **wpointer = arr2;
++
++ size_t r = sizeof(keychords)/ sizeof(Keychord*);
++
++ while(1){
++ ev = &event.xkey;
++ keysym = XKeycodeToKeysym(dpy, (KeyCode)ev->keycode, 0);
++ size_t w = 0;
++ for (int i = 0; i < r; i++){
++ if(keysym == (*(rpointer + i))->keys[currentkey].keysym
++ && CLEANMASK((*(rpointer + i))->keys[currentkey].mod) == CLEANMASK(ev->state)
++ && (*(rpointer + i))->func){
++ if((*(rpointer + i))->n == currentkey +1){
++ (*(rpointer + i))->func(&((*(rpointer + i))->arg));
++ ran = 1;
++ }else{
++ *(wpointer + w) = *(rpointer + i);
++ w++;
++ }
++ }
++ }
++ currentkey++;
++ if(w == 0 || ran == 1)
++ break;
++ grabkeys();
++ /* Events arriving mid-chord must be dispatched, not dropped:
++ * discarding a ButtonPress that activated the GrabModeSync grab
++ * from grabbuttons() freezes pointer and keyboard permanently,
++ * since only buttonpress()'s XAllowEvents can release it. */
++ while (running && !XNextEvent(dpy, &event)) {
++ if (event.type == KeyPress)
++ break;
++ if (handler[event.type])
++ handler[event.type](&event); /* call handler */
++ }
++ r = w;
++ Keychord **holder = rpointer;
++ rpointer = wpointer;
++ wpointer = holder;
++ }
++ currentkey = 0;
++ grabkeys();
+ }
+
+ void
+--
+2.47.3
+
DIR diff --git a/dwm.suckless.org/patches/keychord/index.md b/dwm.suckless.org/patches/keychord/index.md
@@ -11,14 +11,26 @@ change implementation to use array and pointer instead of dynamic heap allocatio
*update 07/19/2023:
changed grabkeys function to match the changes made in dwm-6.4.
+*update 2026-07-17:
+rebased onto dwm 6.8 and fixed event loss in the chord wait loop. While
+waiting for the next key of a chord, every event that was not a KeyPress was
+discarded. Discarding a ButtonPress that activated the GrabModeSync passive
+grab from grabbuttons() left the pointer and keyboard frozen permanently: only
+buttonpress()'s XAllowEvents can release that grab, and the loop could never
+exit because a frozen keyboard cannot deliver the KeyPress it waits for. A
+MapRequest arriving mid-chord was dropped the same way, leaving the window
+unmanaged. Events are now dispatched through handler[] as run() does.
+
Download
--------
* [dwm-keychord-20211210-a786211.diff](dwm-keychord-20211210-a786211.diff) (10/12/2021)
* [dwm-keychord-6.2.diff](dwm-keychord-6.2.diff) (01/19/2022)
-* [dwm-keychord-6.4.diff](dwm-keychord-6.4.diff) (07/19/2023) (latest version)
+* [dwm-keychord-6.4.diff](dwm-keychord-6.4.diff) (07/19/2023) (applies to dwm 6.5-6.8, not 6.4)
+* [dwm-keychord-20260717-f63cde9.diff](dwm-keychord-20260717-f63cde9.diff) (2026-07-17) (latest version, dwm 6.8)
Authors
-------
* Hai Nguyen - <hhai2105@gmail.com>
* Aaron Züger - <contact@azureorange.xyz>
+* Lukasz Kasprzak - <lukas@labunix.xyz>