Implement kill-buffer command

Can be killed with the command `kill-buffer`, the shortcut `C-x k`
or from the buffer menu.

1 files changed, 83 insertions, 13 deletions

diff --git a/src/dged/buffers.c b/src/dged/buffers.c
index 99dad9a..f591385 100644
--- a/src/dged/buffers.c
+++ b/src/dged/buffers.c
@@ -1,24 +1,42 @@
 #include "buffers.h"
 #include "buffer.h"
 
+#include <stdbool.h>
 #include <stdlib.h>
-
 #include <string.h>
 
+struct buffer_entry {
+  struct buffer buffer;
+  bool empty;
+};
+
 void buffers_init(struct buffers *buffers, uint32_t initial_capacity) {
   VEC_INIT(&buffers->buffers, initial_capacity);
   VEC_INIT(&buffers->add_hooks, 32);
+  VEC_INIT(&buffers->remove_hooks, 32);
 }
 
 struct buffer *buffers_add(struct buffers *buffers, struct buffer buffer) {
-  VEC_PUSH(&buffers->buffers, buffer);
+  struct buffer_entry *slot = NULL;
+  VEC_FOR_EACH(&buffers->buffers, struct buffer_entry * e) {
+    if (e->empty) {
+      slot = e;
+    }
+  }
+
+  if (slot == NULL) {
+    VEC_APPEND(&buffers->buffers, struct buffer_entry * new);
+    slot = new;
+  }
+
+  slot->buffer = buffer;
+  slot->empty = false;
 
-  struct buffer *slot = VEC_BACK(&buffers->buffers);
   VEC_FOR_EACH(&buffers->add_hooks, struct buffers_hook * hook) {
-    hook->callback(slot, hook->userdata);
+    hook->callback(&slot->buffer, hook->userdata);
   }
 
-  return slot;
+  return &slot->buffer;
 }
 
 uint32_t buffers_add_add_hook(struct buffers *buffers, buffers_hook_cb callback,
@@ -31,10 +49,20 @@ uint32_t buffers_add_add_hook(struct buffers *buffers, buffers_hook_cb callback,
   return VEC_SIZE(&buffers->add_hooks) - 1;
 }
 
+uint32_t buffers_add_remove_hook(struct buffers *buffers,
+                                 buffers_hook_cb callback, void *userdata) {
+  VEC_PUSH(&buffers->remove_hooks, ((struct buffers_hook){
+                                       .callback = callback,
+                                       .userdata = userdata,
+                                   }));
+
+  return VEC_SIZE(&buffers->remove_hooks) - 1;
+}
+
 struct buffer *buffers_find(struct buffers *buffers, const char *name) {
-  VEC_FOR_EACH(&buffers->buffers, struct buffer * b) {
-    if (strcmp(name, b->name) == 0) {
-      return b;
+  VEC_FOR_EACH(&buffers->buffers, struct buffer_entry * e) {
+    if (!e->empty && strcmp(name, e->buffer.name) == 0) {
+      return &e->buffer;
     }
   }
 
@@ -43,23 +71,65 @@ struct buffer *buffers_find(struct buffers *buffers, const char *name) {
 
 struct buffer *buffers_find_by_filename(struct buffers *buffers,
                                         const char *path) {
-  VEC_FOR_EACH(&buffers->buffers, struct buffer * b) {
-    if (b->filename != NULL && strcmp(path, b->filename) == 0) {
-      return b;
+  VEC_FOR_EACH(&buffers->buffers, struct buffer_entry * e) {
+    if (!e->empty && e->buffer.filename != NULL &&
+        strcmp(path, e->buffer.filename) == 0) {
+      return &e->buffer;
     }
   }
 
   return NULL;
 }
 
+bool buffers_remove(struct buffers *buffers, const char *name) {
+  struct buffer_entry *buf_entry = NULL;
+  VEC_FOR_EACH(&buffers->buffers, struct buffer_entry * e) {
+    if (!e->empty && strcmp(name, e->buffer.name) == 0) {
+      buf_entry = e;
+    }
+  }
+
+  if (buf_entry == NULL) {
+    return false;
+  }
+
+  VEC_FOR_EACH(&buffers->remove_hooks, struct buffers_hook * hook) {
+    hook->callback(&buf_entry->buffer, hook->userdata);
+  }
+
+  buf_entry->empty = true;
+  buffer_destroy(&buf_entry->buffer);
+  return true;
+}
+
 void buffers_for_each(struct buffers *buffers, buffers_hook_cb callback,
                       void *userdata) {
-  VEC_FOR_EACH(&buffers->buffers, struct buffer * b) { callback(b, userdata); }
+  VEC_FOR_EACH(&buffers->buffers, struct buffer_entry * e) {
+    if (!e->empty) {
+      callback(&e->buffer, userdata);
+    }
+  }
+}
+
+uint32_t buffers_num_buffers(struct buffers *buffers) {
+  return VEC_SIZE(&buffers->buffers);
+}
+
+struct buffer *buffers_first(struct buffers *buffers) {
+  return buffers_num_buffers(buffers) > 0
+             ? &VEC_ENTRIES(&buffers->buffers)[0].buffer
+             : NULL;
 }
 
 void buffers_destroy(struct buffers *buffers) {
-  VEC_FOR_EACH(&buffers->buffers, struct buffer * b) { buffer_destroy(b); }
+  VEC_FOR_EACH(&buffers->buffers, struct buffer_entry * e) {
+    if (!e->empty) {
+      buffer_destroy(&e->buffer);
+      e->empty = true;
+    }
+  }
 
   VEC_DESTROY(&buffers->buffers);
   VEC_DESTROY(&buffers->add_hooks);
+  VEC_DESTROY(&buffers->remove_hooks);
 }