feat: add --cursor-size flag for standalone pointer size

New --cursor-size N (8..128px, both --cursor-size N and --cursor-size=N forms) sizing the standalone wlr_cursor. Precedence: CLI flag over $XCURSOR_SIZE over the 24px default. Out-of-range, missing or non-numeric values are startup errors (rc 2) naming the flag, matching the existing --start-cmd-index/--tab-groups handling. Nested mode is unaffected (the host draws the pointer there); the flag is silently ignored. Help text, README usage + cursor-shapes section, and a test_cursor_size_flag_errors regression test included. Verified: debug + release builds warning-free; cursor_size + tab-groups flag-error tests pass; --cursor-size 32 boots headless, --cursor-size 999 exits rc 2.

README.md

@@ -75,7 +75,7 @@ install works too.
 ## Usage
 
 ```
-kick [--start-cmd-index N] [--focus-priority] [prog...]
+kick [--start-cmd-index N] [--focus-priority] [--cursor-size N] [prog...]
 ```
 
 Each `<prog>` is one shell command; quote it when it takes arguments, e.g.
@@ -428,10 +428,12 @@ version 1). Nested clients that switch the pointer's cursor shape are honoured:
 
 - **Standalone** mode applies the requested shape to the compositor's own
   cursor, looked up in the current `XCURSOR_THEME` (so e.g. GTK's text cursor
-  works over a galculator entry).
+  works over a galculator entry). Pass `--cursor-size N` (8..128px,
+  default 24 or `$XCURSOR_SIZE` when set) to size that cursor.
 - **Nested** mode has no cursor of its own: the shape is forwarded to the host
   compositor's pointer via `wp_cursor_shape_device_v1.set_shape`, and the host
-  (which draws the cursor over our window) applies it.
+  (which draws the cursor over our window) applies it. `--cursor-size` is
+  ignored there.
 
 The shape is remembered per tab and the cursor is reset to `default` when you
 switch to a tab whose client last asked for nothing (or asked for `default`),

kick.c

@@ -928,6 +928,11 @@ static bool opt_focus_priority = false;
    text row.  Off by default. */
 static bool opt_overlay_previews = false;
 
+/* --cursor-size N: standalone pointer size in px (8..128).  -1 means unset:
+   fall back to $XCURSOR_SIZE, then the 24px default.  Nested mode has no
+   cursor of its own (the host draws the pointer), so it is ignored there. */
+static int opt_cursor_size = -1;
+
 /* ===================== Clipboard bridge ===================== */
 
 enum bridge_backend {
@@ -13901,6 +13906,13 @@ int main(int argc, char *argv[]) {
                     "that starts\n"
                     "                               focused; without it the "
                     "last command does.\n"
+                    "  --cursor-size N              Standalone pointer size "
+                    "in px (8..128;\n"
+                    "                               default 24, or "
+                    "$XCURSOR_SIZE when set).\n"
+                    "                               Ignored when nested: the "
+                    "host draws the\n"
+                    "                               pointer there.\n"
                      "  --tab-groups on|off         How a client's related "
                      "windows group with their tab:\n"
                      "                               'on' (default) stacks them "
@@ -14101,6 +14113,37 @@ int main(int argc, char *argv[]) {
             }
             start_cmd_index = (int)idx - 1;
             continue;
+        } else if (strcmp(argv[i], "--cursor-size") == 0) {
+            if (i + 1 >= argc) {
+                fprintf(stderr, "kick: --cursor-size needs a "
+                        "value, e.g. --cursor-size 32\n");
+                free(appv);
+                return 2;
+            }
+            const char *n = argv[++i];
+            char *end = NULL;
+            long sz = strtol(n, &end, 10);
+            if (end == n || *end != '\0' || sz < 8 || sz > 128) {
+                fprintf(stderr, "kick: bad --cursor-size '%s' "
+                        "(use 8..128, e.g. --cursor-size 32)\n", n);
+                free(appv);
+                return 2;
+            }
+            opt_cursor_size = (int)sz;
+            continue;
+        } else if (strncmp(argv[i], "--cursor-size=",
+                           sizeof("--cursor-size=") - 1) == 0) {
+            const char *n = argv[i] + sizeof("--cursor-size=") - 1;
+            char *end = NULL;
+            long sz = strtol(n, &end, 10);
+            if (end == n || *end != '\0' || sz < 8 || sz > 128) {
+                fprintf(stderr, "kick: bad --cursor-size '%s' "
+                        "(use 8..128, e.g. --cursor-size 32)\n", n);
+                free(appv);
+                return 2;
+            }
+            opt_cursor_size = (int)sz;
+            continue;
         }
         if (val) {
             if (!parse_screen_mode(val)) {
@@ -14734,7 +14777,8 @@ int main(int argc, char *argv[]) {
 
     /* Standalone has no host compositor to draw a pointer, so give the
        output a real wlr_cursor.  Theme/size follow the XDG cursor convention:
-       XCURSOR_THEME (default "default") and XCURSOR_SIZE (default 24px).
+       XCURSOR_THEME (default "default") and XCURSOR_SIZE (default 24px),
+       with --cursor-size overriding the size when given.
        wlroots resolves the theme itself (search path, Inherits chains) and,
        when nothing is installed, substitutes a builtin arrow -- so the pointer
        is never invisible.  We only report when the requested theme was
@@ -14758,6 +14802,9 @@ int main(int argc, char *argv[]) {
             if (end != size_env && v > 0)
                 size = (uint32_t)v;
         }
+        /* Explicit --cursor-size wins over the environment. */
+        if (opt_cursor_size > 0)
+            size = (uint32_t)opt_cursor_size;
 
         server.xcursor_mgr = wlr_xcursor_manager_create(theme, size);
         if (server.xcursor_mgr)

tests/test_smoke.py

@@ -4229,6 +4229,36 @@ def test_sub_windows_flag_errors():
             f"error should mention --tab-groups:\n{out}"
 
 
+def test_cursor_size_flag_errors():
+    """A missing or bad --cursor-size value is a startup error (rc 2) naming
+    the flag, before any window or backend work."""
+    env = dict(os.environ)
+    cases = (["--cursor-size"],
+             ["--cursor-size", "0"],
+             ["--cursor-size", "7"],
+             ["--cursor-size", "129"],
+             ["--cursor-size", "big"],
+             ["--cursor-size=foo"])
+    for case in cases:
+        proc = subprocess.Popen(
+            ["env", "-i",
+             "PATH=" + env["PATH"],
+             "HOME=" + env.get("HOME", "/"),
+             "XDG_RUNTIME_DIR=" + env.get("XDG_RUNTIME_DIR", "/tmp"),
+             "KICK_MODE=standalone",
+             "WLR_BACKENDS=headless",
+             "stdbuf", "-oL",
+             BIN] + case,
+            stdout=subprocess.PIPE, stderr=subprocess.STDOUT,
+            preexec_fn=_preexec_death(os.getpid()),
+        )
+        out, _ = proc.communicate(timeout=15)
+        assert proc.returncode == 2, \
+            f"--cursor-size {case} should exit rc 2; rc={proc.returncode}\n{out}"
+        assert b"--cursor-size" in out, \
+            f"error should mention --cursor-size:\n{out}"
+
+
 @pytest.mark.flaky
 def test_dead_command_explains_and_exits():
     """A sole command that exits before opening a window is dropped with a