Fix sporadic crash when pressing enter

What happened here is that when a buffer (like for example the
choice-buffer) is killed, it left keybindings behind. Since the
buffer list is a pool, the next opened buffer would get the same
buffer pointer and therefore also inherit the keybindings. This
makes sure that when buffers are removed, their keymaps are cleared.

Also, make sure that completion state for a buffer is removed when
the buffer is removed.

Author: abbec

src/main/bindings.c

@@ -19,7 +19,9 @@ struct buffer_keymap {
   struct keymap keymap;
 };
 
-static VEC(struct buffer_keymap) g_buffer_keymaps;
+typedef VEC(struct buffer_keymap) buffer_keymap_vec;
+
+static buffer_keymap_vec g_buffer_keymaps;
 static buffer_keymap_id g_current_keymap_id;
 
 struct keymap *buffer_default_keymap(void) { return &g_buffer_default_keymap; }
@@ -194,6 +196,19 @@ void buffer_remove_keymap(buffer_keymap_id id) {
   }
 }
 
+void buffer_remove_keymaps(struct buffer *buffer) {
+  buffer_keymap_vec new;
+  VEC_INIT(&new, VEC_SIZE(&g_buffer_keymaps));
+  VEC_FOR_EACH_INDEXED(&g_buffer_keymaps, struct buffer_keymap * km, i) {
+    if (km->buffer != buffer) {
+      VEC_PUSH(&new, *km);
+    }
+  }
+
+  VEC_DESTROY(&g_buffer_keymaps);
+  g_buffer_keymaps = new;
+}
+
 uint32_t buffer_keymaps(struct buffer *buffer, struct keymap *keymaps[],
                         uint32_t max_nkeymaps) {
   uint32_t nkeymaps = 0;

src/main/bindings.h

@@ -1,3 +1,6 @@
+#ifndef _BINDINGS_H
+#define _BINDINGS_H
+
 #include <stdint.h>
 
 #include "dged/hook.h"
@@ -6,19 +9,89 @@ struct keymap;
 struct buffer;
 struct binding;
 
+/**
+ * Intialize all structures for bindings and set
+ * default bindings up.
+ */
 void init_bindings(void);
 
+/**
+ * Get the default keymap for buffers.
+ *
+ * @returns The default buffer keymap.
+ */
 struct keymap *buffer_default_keymap(void);
 
+/** Id for a keymap currently added to a buffer. */
 typedef uint64_t buffer_keymap_id;
+
+/**
+ * Add a keymap to a buffer.
+ *
+ * @param [in] buffer The buffer to add the keymap to.
+ * @param [in] keymap The keymap to add.
+ *
+ * @returns A keymap id that can be used to refer to this keymap-buffer
+ *          combination.
+ */
 buffer_keymap_id buffer_add_keymap(struct buffer *buffer, struct keymap keymap);
+
+/**
+ * Remove a keymap for a buffer.
+ *
+ * @param [in] id The id for the buffer keymap to remove.
+ */
 void buffer_remove_keymap(buffer_keymap_id id);
+
+/**
+ * Retrieve keymaps for a buffer.
+ *
+ * @param [in] buffer The buffer to get applicable keymaps for.
+ * @param [in] keymaps An array to store keymaps in.
+ * @param [in] The capacity of @ref keymaps.
+ * @returns The number of keymaps stored in @ref keymaps.
+ */
 uint32_t buffer_keymaps(struct buffer *buffer, struct keymap *keymaps[],
                         uint32_t max_nkeymaps);
 
+/**
+ * Remove all keymaps for a buffer.
+ *
+ * @param [in] buffer The buffer to remove keymaps for.
+ */
+void buffer_remove_keymaps(struct buffer *buffer);
+
+/** Callback for a buffer keymaps hook */
 typedef uint32_t (*buffer_keymaps_cb)(struct buffer *, struct keymap **,
                                       uint32_t, void *);
+
+/**
+ * Add a hook for buffer keymaps
+ *
+ * This makes it possible to programatically append to the list that
+ * is returned by @ref buffer_keymaps.
+ *
+ * @param [in] callback The callback function to call.
+ * @param [in] userdata The userdata to pass to the callback function.
+ *
+ @ @returns The hook id.
+ */
 uint32_t buffer_add_keymaps_hook(buffer_keymaps_cb callback, void *userdata);
+
+/**
+ * Remove a previously added hook for buffer keymaps.
+ *
+ * @param [in] id The id of the hook to remove.
+ * @param [in] callback A callback function called with the userdata of the
+ *             original hook for doing cleanup.
+ */
 void buffer_remove_keymaps_hook(uint32_t id, remove_hook_cb callback);
 
+/**
+ * Tear down the structures for bindings.
+ *
+ * Symmetric to @ref init_bindings.
+ */
 void destroy_bindings(void);
+
+#endif

src/main/cmds.c

@@ -184,12 +184,12 @@ int32_t do_kill_buffer(struct command_ctx ctx, int argc, const char *argv[]) {
     bufname = argv[0];
   }
 
-  if (buffers_remove(ctx.buffers, bufname)) {
-    return 0;
-  } else {
+  if (!buffers_remove(ctx.buffers, bufname)) {
     minibuffer_echo_timeout(4, "buffer %s not found", bufname);
     return 1;
   }
+
+  return 0;
 }
 
 COMMAND_FN("do-kill-buffer", do_kill_buffer, do_kill_buffer, NULL)

src/main/completion.c

@@ -388,6 +388,14 @@ static void on_buffer_delete(struct buffer *buffer, struct edit_location edit,
   on_buffer_changed(buffer, edit, true, userdata);
 }
 
+static void on_buffer_destroy(struct buffer *buffer,
+                              struct completion_state *state) {
+  (void)state;
+
+  // remove the buffer from our state
+  disable_completion(buffer);
+}
+
 static void completions_buffer_deleted(struct buffer *buffer, void *userdata) {
   (void)buffer;
   struct completion_state *state = (struct completion_state *)userdata;
@@ -441,6 +449,9 @@ void add_completion_providers(struct buffer *source,
     uint32_t remove_hook_id =
         buffer_add_delete_hook(source, on_buffer_delete, &g_state);
 
+    buffer_add_destroy_hook(source, (destroy_hook_cb)on_buffer_destroy,
+                            &g_state);
+
     new_comp->buffer = source;
     new_comp->insert_hook_id = insert_hook_id;
     new_comp->remove_hook_id = remove_hook_id;

src/main/lsp/choice-buffer.c

@@ -30,6 +30,8 @@ struct choice_buffer {
 
   struct command enter_pressed;
   struct command q_pressed;
+
+  buffer_keymap_id keymap_id;
 };
 
 static void delete_choice_buffer(struct choice_buffer *buffer,
@@ -126,7 +128,7 @@ choice_buffer_create(struct s8 title, struct buffers *buffers,
 
   struct keymap km = keymap_create("choice_buffer", 8);
   keymap_bind_keys(&km, bindings, sizeof(bindings) / sizeof(bindings[0]));
-  buffer_add_keymap(b->buffer, km);
+  b->keymap_id = buffer_add_keymap(b->buffer, km);
 
   struct location begin = buffer_end(b->buffer);
   buffer_add(b->buffer, buffer_end(b->buffer), title.s, title.l);
@@ -195,6 +197,7 @@ static void delete_choice_buffer(struct choice_buffer *buffer,
   if (delete_underlying) {
     buffer_remove_destroy_hook(buffer->buffer, buffer->buffer_removed_hook,
                                NULL);
+    buffer_remove_keymap(buffer->keymap_id);
     buffers_remove(buffer->buffers, buffer->buffer->name);
   }
 

src/main/main.c

@@ -58,15 +58,15 @@ void *frame_alloc(size_t sz) {
 
 static bool running = true;
 
-void terminate(void) { running = false; }
-void terminate2(int sig) {
+static void terminate(void) { running = false; }
+static void terminate2(int sig) {
   (void)sig;
   running = false;
 }
 
 static struct display *display = NULL;
 static bool display_resized = false;
-void resized(int sig) {
+static void resized(int sig) {
   (void)sig;
   if (display != NULL) {
     display_resize(display);
@@ -76,7 +76,7 @@ void resized(int sig) {
   signal(SIGWINCH, resized);
 }
 
-void terminal_stop(int sig) {
+static void terminal_stop(int sig) {
   (void)sig;
   if (display != NULL) {
     display_clear(display);
@@ -88,14 +88,14 @@ void terminal_stop(int sig) {
 #endif
 }
 
-void suspend() { terminal_stop(0); }
+static void suspend() { terminal_stop(0); }
 
-void resume(int sig) {
+static void resume(int sig) {
   (void)sig;
   display_initialize(display);
 }
 
-void handle_crash(int sig) {
+static void handle_crash(int sig) {
   (void)sig;
 
   // make an effort to restore the
@@ -116,6 +116,11 @@ void handle_crash(int sig) {
   }
 }
 
+static void cleanup_buffer_bindings(struct buffer *buffer, void *userdata) {
+  (void)userdata;
+  buffer_remove_keymaps(buffer);
+}
+
 #define INVALID_WATCH (uint32_t) - 1
 
 struct watched_file {
@@ -322,6 +327,7 @@ int main(int argc, char *argv[]) {
   minibuffer_init(&minibuffer, &buflist);
 
   buffers_add_add_hook(&buflist, watch_file, (void *)reactor);
+  buffers_add_remove_hook(&buflist, cleanup_buffer_bindings, NULL);
 
   init_bindings();