rename and simplification

1 files changed, 629 insertions, 0 deletions

diff --git a/src/platform/wayland/clipboard.c b/src/platform/wayland/clipboard.c
new file mode 100644
index 0000000..a6922c4
--- /dev/null
+++ b/src/platform/wayland/clipboard.c
@@ -0,0 +1,629 @@
+#define _GNU_SOURCE
+#include "internal.h"
+#include "clipboard.h"
+
+#define CLIPBOARD_TEXT_MAX (256u * 1024)
+
+struct offer {
+    struct offer *next;
+    struct wl_data_offer *proxy;
+    char *mime;
+    bool uri_list;
+    bool tab;
+};
+struct primary_offer {
+    struct primary_offer *next;
+    struct zwp_primary_selection_offer_v1 *proxy;
+    char *mime;
+};
+struct transfer {
+    struct transfer *next;
+    struct clipboard *owner;
+    struct offer *drop;
+    struct wl_surface *drop_surface;
+    int fd, id;
+    char *text;
+    size_t len, offset, capacity;
+    bool sending;
+    bool uri_list;
+};
+struct clipboard {
+    struct wl_display *display;
+    struct wl_data_device_manager *manager;
+    struct wl_data_device *device;
+    struct zwp_primary_selection_device_manager_v1 *primary_manager;
+    struct zwp_primary_selection_device_v1 *primary_device;
+    struct zwp_primary_selection_source_v1 *primary_source;
+    struct wl_seat *seat;
+    struct wl_data_source *source;
+    struct offer *selection;
+    struct offer *pending_offers;
+    struct offer *drag_offer;
+    struct primary_offer *primary_selection;
+    struct primary_offer *primary_pending_offers;
+    struct yasl_loop *loop;
+    struct transfer *transfers;
+    char *text;
+    char *primary_text;
+    clipboard_receive_fn receive;
+    void *ud;
+    clipboard_drag_fn drag;
+    void *drag_ud;
+    clipboard_drop_fn drop;
+    void *drop_ud;
+    wl_fixed_t drag_x, drag_y;
+    struct wl_surface *drag_surface;
+};
+
+const char *clipboard_drag_mime(void)
+{
+    static char mime[64];
+    if (!mime[0])
+        snprintf(mime, sizeof(mime), "application/x-yasl-tab;pid=%ld", (long)getpid());
+    return mime;
+}
+
+static void drag_event(struct clipboard *c, enum yasl_drag_event ev,
+                       wl_fixed_t x, wl_fixed_t y)
+{
+    if (c->drag)
+        c->drag(ev, c->drag_surface, wl_fixed_to_double(x), wl_fixed_to_double(y),
+                c->drag_ud);
+}
+
+static bool offer_droppable(const struct offer *o)
+{
+    return o && !o->tab && (o->uri_list || o->mime);
+}
+
+static void drop_event(struct clipboard *c, enum yasl_drop_event ev)
+{
+    if (c->drop && c->drag_surface)
+        c->drop(ev, c->drag_surface, wl_fixed_to_double(c->drag_x),
+                wl_fixed_to_double(c->drag_y), c->drop_ud);
+}
+
+static void free_offer(struct offer *o);
+
+static void transfer_end(struct transfer *t, bool complete)
+{
+    struct transfer **p = &t->owner->transfers;
+    while (*p && *p != t) p = &(*p)->next;
+    if (*p) *p = t->next;
+    yasl_loop_del_fd(t->owner->loop, t->id);
+    close(t->fd);
+    if (t->drop) {
+        if (complete && wl_data_offer_get_version(t->drop->proxy) >=
+                WL_DATA_OFFER_FINISH_SINCE_VERSION)
+            wl_data_offer_finish(t->drop->proxy);
+        free_offer(t->drop);
+        wl_display_flush(t->owner->display);
+    }
+    free(t->text);
+    free(t);
+}
+
+static void transfer_destroy(struct transfer *t)
+{
+    transfer_end(t, false);
+}
+
+static int transfer_io(int fd, short events, void *ud)
+{
+    struct transfer *t = ud;
+    if (events & (POLLERR | POLLNVAL)) { transfer_destroy(t); return 0; }
+    if (t->sending) {
+        ssize_t n = write(fd, t->text + t->offset, t->len - t->offset);
+        if (n > 0) t->offset += (size_t)n;
+        if (t->offset == t->len || n == 0 ||
+            (n < 0 && errno != EAGAIN && errno != EINTR)) transfer_destroy(t);
+    } else {
+        if (t->capacity - t->len < 4096) {
+            size_t capacity = t->capacity ? t->capacity * 2 : 8192;
+            if (capacity > CLIPBOARD_TEXT_MAX) capacity = CLIPBOARD_TEXT_MAX;
+            if (capacity <= t->len) { transfer_destroy(t); return 0; }
+            char *text = realloc(t->text, capacity);
+            if (!text) { transfer_destroy(t); return 0; }
+            t->text = text;
+            t->capacity = capacity;
+        }
+        ssize_t n = read(fd, t->text + t->len, t->capacity - t->len);
+        if (n > 0) {
+            t->len += (size_t)n;
+        } else if (n == 0) {
+            bool valid = yasl_utf8_validate(t->text, t->len);
+            if (valid)
+                t->owner->receive(t->text ? t->text : "", t->len, t->uri_list,
+                                  t->drop_surface, t->owner->ud);
+            transfer_end(t, valid);
+        } else if (errno != EAGAIN && errno != EINTR) transfer_destroy(t);
+    }
+    return 0;
+}
+
+static struct transfer *start_transfer_text(struct clipboard *c, int fd, bool sending,
+                                            bool uri_list, const char *send_text)
+{
+    struct transfer *t = calloc(1, sizeof(*t));
+    if (!t) { close(fd); return NULL; }
+    t->owner = c; t->fd = fd; t->sending = sending; t->uri_list = uri_list;
+    fcntl(fd, F_SETFD, FD_CLOEXEC);
+    fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) | O_NONBLOCK);
+    if (sending) {
+        t->text = strdup(send_text ? send_text : "");
+        if (!t->text) { close(fd); free(t); return NULL; }
+        t->len = strlen(t->text);
+    }
+    t->id = yasl_loop_add_fd(c->loop, fd, sending ? POLLOUT : POLLIN, transfer_io, t);
+    if (t->id < 0) { close(fd); free(t->text); free(t); return NULL; }
+    t->next = c->transfers; c->transfers = t;
+    return t;
+}
+
+static struct transfer *start_transfer(struct clipboard *c, int fd, bool sending, bool uri_list)
+{
+    return start_transfer_text(c, fd, sending, uri_list, c->text);
+}
+
+static const char *match_text_mime(const char *mime)
+{
+    if (unlikely(!mime)) return NULL;
+    if (likely(!strncasecmp(mime, "text/plain", 10))) {
+        if (!strcasecmp(mime, "text/plain;charset=utf-8")) return "text/plain;charset=utf-8";
+        if (!strcasecmp(mime, "text/plain;charset=utf8")) return "text/plain;charset=utf8";
+        if (!strcasecmp(mime, "text/plain")) return "text/plain";
+    }
+    if (!strcasecmp(mime, "UTF8_STRING")) return "UTF8_STRING";
+    if (!strcasecmp(mime, "STRING")) return "STRING";
+    if (!strcasecmp(mime, "TEXT")) return "TEXT";
+    return NULL;
+}
+
+static void offer_keep_mime(char **slot, const char *mime)
+{
+    char *copy = strdup(mime);
+    if (!copy) return;
+    free(*slot);
+    *slot = copy;
+}
+
+static void offer_mime(void *ud, struct wl_data_offer *proxy, const char *mime)
+{
+    (void)proxy;
+    struct offer *o = ud;
+    if (!strcmp(mime, clipboard_drag_mime())) o->tab = true;
+    if (!strcmp(mime, "text/uri-list")) o->uri_list = true;
+    const char *match = match_text_mime(mime);
+    if (match) {
+        if (!o->mime || !strcasecmp(match, "text/plain;charset=utf-8"))
+            offer_keep_mime(&o->mime, mime);
+    }
+}
+static void offer_source_actions(void *ud, struct wl_data_offer *proxy, uint32_t actions)
+{ (void)ud; (void)proxy; (void)actions; }
+static void offer_action(void *ud, struct wl_data_offer *proxy, uint32_t action)
+{ (void)ud; (void)proxy; (void)action; }
+static const struct wl_data_offer_listener offer_listener = {
+    .offer = offer_mime,
+    .source_actions = offer_source_actions,
+    .action = offer_action,
+};
+static void free_offer(struct offer *o)
+{
+    if (o) { wl_data_offer_destroy(o->proxy); free(o->mime); free(o); }
+}
+static void take_pending_offer(struct clipboard *c, struct offer *o)
+{
+    if (!o) return;
+    struct offer **p = &c->pending_offers;
+    while (*p && *p != o) p = &(*p)->next;
+    if (*p) *p = o->next;
+    o->next = NULL;
+}
+static void clear_pending_offers(struct clipboard *c)
+{
+    while (c->pending_offers) {
+        struct offer *o = c->pending_offers;
+        c->pending_offers = o->next;
+        free_offer(o);
+    }
+}
+static void data_offer(void *ud, struct wl_data_device *device, struct wl_data_offer *proxy)
+{
+    (void)device;
+    struct clipboard *c = ud;
+    struct offer *o = calloc(1, sizeof(*o));
+    if (!o) { wl_data_offer_destroy(proxy); return; }
+    o->proxy = proxy;
+    wl_data_offer_add_listener(proxy, &offer_listener, o);
+    o->next = c->pending_offers;
+    c->pending_offers = o;
+}
+static void selection(void *ud, struct wl_data_device *device, struct wl_data_offer *proxy)
+{
+    (void)device;
+    struct clipboard *c = ud;
+    struct offer *o = proxy ? wl_data_offer_get_user_data(proxy) : NULL;
+    take_pending_offer(c, o);
+    if (c->drag_offer == o) c->drag_offer = NULL;
+    if (c->selection != o) free_offer(c->selection);
+    c->selection = o;
+}
+static void drag_offer_enter(void *ud, struct wl_data_device *device, uint32_t serial,
+                       struct wl_surface *surface, wl_fixed_t x, wl_fixed_t y, struct wl_data_offer *proxy)
+{
+    (void)device;
+    if (proxy) {
+        struct clipboard *c = ud;
+        struct offer *o = wl_data_offer_get_user_data(proxy);
+        take_pending_offer(c, o);
+        if (c->selection == o) c->selection = NULL;
+        if (c->drag_offer && c->drag_offer != o) free_offer(c->drag_offer);
+        c->drag_offer = o;
+        const char *mime = o && o->tab ? clipboard_drag_mime()
+                         : o && o->uri_list ? "text/uri-list"
+                         : o ? o->mime : NULL;
+        wl_data_offer_accept(proxy, serial, mime);
+        if (mime && wl_data_offer_get_version(proxy) >= 3) {
+            uint32_t action = o->tab ? WL_DATA_DEVICE_MANAGER_DND_ACTION_MOVE
+                                     : WL_DATA_DEVICE_MANAGER_DND_ACTION_COPY;
+            wl_data_offer_set_actions(proxy, action, action);
+        }
+        c->drag_x = x;
+        c->drag_y = y;
+        c->drag_surface = surface;
+        if (o && o->tab)
+            drag_event(c, YASL_DRAG_OVER, x, y);
+        else if (offer_droppable(o))
+            drop_event(c, YASL_DROP_OVER);
+    }
+}
+static void drag_offer_clear(void *ud, struct wl_data_device *device)
+{
+    (void)device;
+    struct clipboard *c = ud;
+    if (c->drag_offer && c->drag_offer->tab)
+        drag_event(c, YASL_DRAG_LEAVE, c->drag_x, c->drag_y);
+    else if (offer_droppable(c->drag_offer))
+        drop_event(c, YASL_DROP_LEAVE);
+    free_offer(c->drag_offer);
+    c->drag_offer = NULL;
+    c->drag_surface = NULL;
+}
+static void drag_motion(void *ud, struct wl_data_device *device, uint32_t time, wl_fixed_t x, wl_fixed_t y)
+{
+    (void)device; (void)time;
+    struct clipboard *c = ud;
+    c->drag_x = x;
+    c->drag_y = y;
+    if (c->drag_offer && c->drag_offer->tab)
+        drag_event(c, YASL_DRAG_OVER, x, y);
+    else if (offer_droppable(c->drag_offer))
+        drop_event(c, YASL_DROP_OVER);
+}
+static void drag_drop(void *ud, struct wl_data_device *device)
+{
+    (void)device;
+    struct clipboard *c = ud;
+    struct offer *o = c->drag_offer;
+    if (!o) return;
+    c->drag_offer = NULL;
+    bool v3 = wl_data_offer_get_version(o->proxy) >= 3;
+    if (o->tab) {
+        drag_event(c, YASL_DRAG_DROP, c->drag_x, c->drag_y);
+        if (v3)
+            wl_data_offer_finish(o->proxy);
+    } else if (offer_droppable(o)) {
+        drop_event(c, YASL_DROP_LEAVE);
+        int fds[2];
+        if (pipe2(fds, O_CLOEXEC) == 0) {
+            wl_data_offer_receive(o->proxy, o->uri_list ? "text/uri-list" : o->mime, fds[1]);
+            close(fds[1]);
+            struct transfer *t = start_transfer(c, fds[0], false, o->uri_list);
+            if (t) {
+                t->drop = o;
+                t->drop_surface = c->drag_surface;
+                o = NULL;
+            }
+            wl_display_flush(c->display);
+        }
+    }
+    c->drag_surface = NULL;
+    free_offer(o);
+}
+static const struct wl_data_device_listener device_listener = {
+    .data_offer = data_offer, .selection = selection, .enter = drag_offer_enter,
+    .leave = drag_offer_clear, .motion = drag_motion, .drop = drag_drop
+};
+static void source_target(void *ud, struct wl_data_source *s, const char *mime) { (void)ud; (void)s; (void)mime; }
+static void source_send(void *ud, struct wl_data_source *s, const char *mime, int32_t fd)
+{ (void)s; (void)mime; start_transfer(ud, fd, true, false); }
+static void source_cancelled(void *ud, struct wl_data_source *s)
+{
+    struct clipboard *c = ud;
+    if (c->source == s) c->source = NULL;
+    wl_data_source_destroy(s);
+}
+static void source_dnd_drop_performed(void *ud, struct wl_data_source *s) { (void)ud; (void)s; }
+static void source_dnd_finished(void *ud, struct wl_data_source *s) { (void)ud; (void)s; }
+static void source_action(void *ud, struct wl_data_source *s, uint32_t action) { (void)ud; (void)s; (void)action; }
+static const struct wl_data_source_listener source_listener = {
+    .target = source_target, .send = source_send, .cancelled = source_cancelled,
+    .dnd_drop_performed = source_dnd_drop_performed,
+    .dnd_finished = source_dnd_finished, .action = source_action,
+};
+
+static void free_primary_offer(struct primary_offer *o)
+{
+    if (o) { zwp_primary_selection_offer_v1_destroy(o->proxy); free(o->mime); free(o); }
+}
+
+static void take_pending_primary_offer(struct clipboard *c, struct primary_offer *o)
+{
+    if (!o) return;
+    struct primary_offer **p = &c->primary_pending_offers;
+    while (*p && *p != o) p = &(*p)->next;
+    if (*p) *p = o->next;
+    o->next = NULL;
+}
+
+static void clear_pending_primary_offers(struct clipboard *c)
+{
+    while (c->primary_pending_offers) {
+        struct primary_offer *o = c->primary_pending_offers;
+        c->primary_pending_offers = o->next;
+        free_primary_offer(o);
+    }
+}
+
+static void primary_offer_mime(void *ud, struct zwp_primary_selection_offer_v1 *proxy, const char *mime)
+{
+    (void)proxy;
+    struct primary_offer *o = ud;
+    const char *match = match_text_mime(mime);
+    if (match) {
+        if (!o->mime || !strcasecmp(match, "text/plain;charset=utf-8"))
+            offer_keep_mime(&o->mime, mime);
+    }
+}
+
+static const struct zwp_primary_selection_offer_v1_listener primary_offer_listener = {
+    .offer = primary_offer_mime,
+};
+
+static void primary_data_offer(void *ud, struct zwp_primary_selection_device_v1 *device,
+                               struct zwp_primary_selection_offer_v1 *proxy)
+{
+    (void)device;
+    struct clipboard *c = ud;
+    struct primary_offer *o = calloc(1, sizeof(*o));
+    if (!o) { zwp_primary_selection_offer_v1_destroy(proxy); return; }
+    o->proxy = proxy;
+    zwp_primary_selection_offer_v1_add_listener(proxy, &primary_offer_listener, o);
+    o->next = c->primary_pending_offers;
+    c->primary_pending_offers = o;
+}
+
+static void primary_selection(void *ud, struct zwp_primary_selection_device_v1 *device,
+                              struct zwp_primary_selection_offer_v1 *proxy)
+{
+    (void)device;
+    struct clipboard *c = ud;
+    struct primary_offer *o = proxy ? zwp_primary_selection_offer_v1_get_user_data(proxy) : NULL;
+    take_pending_primary_offer(c, o);
+    if (c->primary_selection != o) free_primary_offer(c->primary_selection);
+    c->primary_selection = o;
+}
+
+static const struct zwp_primary_selection_device_v1_listener primary_device_listener = {
+    .data_offer = primary_data_offer,
+    .selection = primary_selection,
+};
+
+static void primary_source_send(void *ud, struct zwp_primary_selection_source_v1 *s,
+                                const char *mime, int32_t fd)
+{
+    (void)s; (void)mime;
+    struct clipboard *c = ud;
+    start_transfer_text(c, fd, true, false, c->primary_text);
+}
+
+static void primary_source_cancelled(void *ud, struct zwp_primary_selection_source_v1 *s)
+{
+    struct clipboard *c = ud;
+    if (c->primary_source == s) c->primary_source = NULL;
+    zwp_primary_selection_source_v1_destroy(s);
+}
+
+static const struct zwp_primary_selection_source_v1_listener primary_source_listener = {
+    .send = primary_source_send,
+    .cancelled = primary_source_cancelled,
+};
+
+void clipboard_set_primary_manager(struct clipboard *c,
+                                   struct zwp_primary_selection_device_manager_v1 *mgr)
+{
+    if (!c) return;
+    c->primary_manager = mgr;
+    if (c->primary_device) {
+        zwp_primary_selection_device_v1_destroy(c->primary_device);
+        c->primary_device = NULL;
+    }
+    if (c->primary_manager && c->seat) {
+        c->primary_device =
+            zwp_primary_selection_device_manager_v1_get_device(c->primary_manager, c->seat);
+        if (c->primary_device)
+            zwp_primary_selection_device_v1_add_listener(c->primary_device,
+                                                         &primary_device_listener, c);
+    }
+}
+
+void clipboard_set_drag_handler(struct clipboard *c, clipboard_drag_fn fn, void *ud)
+{
+    if (!c) return;
+    c->drag = fn;
+    c->drag_ud = ud;
+}
+
+void clipboard_set_drop_handler(struct clipboard *c, clipboard_drop_fn fn, void *ud)
+{
+    if (!c) return;
+    c->drop = fn;
+    c->drop_ud = ud;
+}
+
+struct wl_data_device *clipboard_data_device(const struct clipboard *c)
+{
+    return c ? c->device : NULL;
+}
+
+struct clipboard *clipboard_create(struct wl_display *display, struct wl_data_device_manager *manager,
+                                  struct wl_seat *seat, struct yasl_loop *loop,
+                                  clipboard_receive_fn receive, void *ud)
+{
+    if (!manager || !seat) return NULL;
+    struct clipboard *c = calloc(1, sizeof(*c));
+    if (!c) return NULL;
+    c->display = display; c->manager = manager; c->loop = loop; c->receive = receive; c->ud = ud;
+    c->device = wl_data_device_manager_get_data_device(manager, seat);
+    if (!c->device) { free(c); return NULL; }
+    c->seat = seat;
+    wl_data_device_add_listener(c->device, &device_listener, c);
+    return c;
+}
+
+bool clipboard_set_seat(struct clipboard *c, struct wl_seat *seat)
+{
+    if (!c || c->seat == seat) return false;
+    c->seat = seat;
+    drag_offer_clear(c, c->device);
+    if (c->device) {
+        wl_data_device_destroy(c->device);
+        c->device = NULL;
+    }
+    free_offer(c->selection);
+    c->selection = NULL;
+    clear_pending_offers(c);
+    if (c->source) {
+        wl_data_source_destroy(c->source);
+        c->source = NULL;
+    }
+    if (c->primary_device) {
+        zwp_primary_selection_device_v1_destroy(c->primary_device);
+        c->primary_device = NULL;
+    }
+    free_primary_offer(c->primary_selection);
+    c->primary_selection = NULL;
+    clear_pending_primary_offers(c);
+    if (c->primary_source) {
+        zwp_primary_selection_source_v1_destroy(c->primary_source);
+        c->primary_source = NULL;
+    }
+    if (!seat) return true;
+    if (c->manager) {
+        c->device = wl_data_device_manager_get_data_device(c->manager, seat);
+        if (c->device)
+            wl_data_device_add_listener(c->device, &device_listener, c);
+    }
+    if (c->primary_manager) {
+        c->primary_device =
+            zwp_primary_selection_device_manager_v1_get_device(c->primary_manager, seat);
+        if (c->primary_device)
+            zwp_primary_selection_device_v1_add_listener(c->primary_device,
+                                                         &primary_device_listener, c);
+    }
+    return true;
+}
+
+void clipboard_copy(struct clipboard *c, const char *text, uint32_t serial)
+{
+    if (!c || !c->device || !text || !serial) return;
+    char *copy = strdup(text);
+    if (!copy) return;
+    if (c->source) wl_data_source_destroy(c->source);
+    free(c->text); c->text = copy;
+    c->source = wl_data_device_manager_create_data_source(c->manager);
+    if (!c->source) return;
+    wl_data_source_add_listener(c->source, &source_listener, c);
+    wl_data_source_offer(c->source, "text/plain;charset=utf-8");
+    wl_data_source_offer(c->source, "text/plain");
+    wl_data_source_offer(c->source, "UTF8_STRING");
+    wl_data_source_offer(c->source, "STRING");
+    wl_data_source_offer(c->source, "TEXT");
+    wl_data_device_set_selection(c->device, c->source, serial);
+}
+
+void clipboard_paste(struct clipboard *c, struct wl_surface *target)
+{
+    if (!c || !c->device || !c->selection || !c->selection->mime) return;
+    int fds[2];
+    if (pipe2(fds, O_CLOEXEC) < 0) return;
+    wl_data_offer_receive(c->selection->proxy, c->selection->mime, fds[1]);
+    close(fds[1]);
+    struct transfer *t = start_transfer(c, fds[0], false, false);
+    if (t) t->drop_surface = target;
+    wl_display_flush(c->display);
+}
+
+void clipboard_copy_primary(struct clipboard *c, const char *text, uint32_t serial)
+{
+    if (!c || !text || !serial) return;
+    if (!c->primary_device || !c->primary_manager) return;
+    char *copy = strdup(text);
+    if (!copy) return;
+    if (c->primary_source) zwp_primary_selection_source_v1_destroy(c->primary_source);
+    free(c->primary_text); c->primary_text = copy;
+    c->primary_source = zwp_primary_selection_device_manager_v1_create_source(c->primary_manager);
+    if (!c->primary_source) return;
+    zwp_primary_selection_source_v1_add_listener(c->primary_source, &primary_source_listener, c);
+    zwp_primary_selection_source_v1_offer(c->primary_source, "text/plain;charset=utf-8");
+    zwp_primary_selection_source_v1_offer(c->primary_source, "text/plain");
+    zwp_primary_selection_source_v1_offer(c->primary_source, "UTF8_STRING");
+    zwp_primary_selection_source_v1_offer(c->primary_source, "STRING");
+    zwp_primary_selection_source_v1_offer(c->primary_source, "TEXT");
+    zwp_primary_selection_device_v1_set_selection(c->primary_device, c->primary_source, serial);
+}
+
+void clipboard_paste_primary(struct clipboard *c, struct wl_surface *target)
+{
+    if (!c) return;
+    if (c->primary_device && c->primary_selection && c->primary_selection->mime) {
+        int fds[2];
+        if (pipe2(fds, O_CLOEXEC) < 0) return;
+        zwp_primary_selection_offer_v1_receive(c->primary_selection->proxy,
+                                               c->primary_selection->mime, fds[1]);
+        close(fds[1]);
+        struct transfer *t = start_transfer(c, fds[0], false, false);
+        if (t) t->drop_surface = target;
+        wl_display_flush(c->display);
+        return;
+    }
+}
+
+void clipboard_forget_surface(struct clipboard *c, struct wl_surface *surface)
+{
+    if (!c || !surface) return;
+    for (struct transfer *t = c->transfers, *next; t; t = next) {
+        next = t->next;
+        if (t->drop_surface == surface) transfer_destroy(t);
+    }
+    if (c->drag_surface == surface) c->drag_surface = NULL;
+}
+
+void clipboard_destroy(struct clipboard *c)
+{
+    if (!c) return;
+    while (c->transfers)
+        transfer_destroy(c->transfers);
+    free_offer(c->selection);
+    clear_pending_offers(c);
+    free_offer(c->drag_offer);
+    free_primary_offer(c->primary_selection);
+    clear_pending_primary_offers(c);
+    if (c->primary_source) zwp_primary_selection_source_v1_destroy(c->primary_source);
+    if (c->primary_device) zwp_primary_selection_device_v1_destroy(c->primary_device);
+    free(c->primary_text);
+    if (c->source) wl_data_source_destroy(c->source);
+    if (c->device) wl_data_device_destroy(c->device);
+    free(c->text); free(c);
+}