[client/common] move ll from the client into the common code module

common/CMakeLists.txt

@@ -35,6 +35,7 @@ set(COMMON_SOURCES
   src/vector.c
   src/cpuinfo.c
   src/debug.c
+  src/ll.c
 )
 
 add_library(lg_common STATIC ${COMMON_SOURCES})

common/include/common/ll.h

@@ -0,0 +1,99 @@
+/**
+ * Looking Glass
+ * Copyright © 2017-2022 The Looking Glass Authors
+ * https://looking-glass.io
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc., 59
+ * Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#ifndef _H_LL_
+#define _H_LL_
+
+#include <stdbool.h>
+#include <stdlib.h>
+
+#include "common/locking.h"
+
+struct ll_item
+{
+  void           * data;
+  struct ll_item * prev, * next;
+};
+
+struct ll
+{
+  struct ll_item * head;
+  struct ll_item * tail;
+  unsigned int count;
+  LG_Lock lock;
+};
+
+struct ll *  ll_new();
+void         ll_free     (struct ll * list);
+void         ll_push     (struct ll * list, void * data);
+bool         ll_shift    (struct ll * list, void ** data);
+bool         ll_peek_head(struct ll * list, void ** data);
+bool         ll_peek_tail(struct ll * list, void ** data);
+
+#define ll_lock(ll) LG_LOCK((ll)->lock)
+#define ll_unlock(ll) LG_UNLOCK((ll)->lock)
+
+#define ll_forEachNL(ll, item, v) \
+  for(struct ll_item * item = (ll)->head, \
+      * _ = (item) ? (item)->next : NULL; (item); (item) = NULL) \
+    for((v) = (__typeof__(v))((item)->data); (item); (item) = _, \
+        _   = (item) ? (item)->next : NULL, \
+        (v) = (item) ? (__typeof__(v))((item)->data) : NULL)
+
+static inline unsigned int ll_count(struct ll * list)
+{
+  return list->count;
+}
+
+static inline void ll_removeNL(struct ll * list, struct ll_item * item)
+{
+  --list->count;
+
+  if (list->head == item)
+    list->head = item->next;
+
+  if (list->tail == item)
+    list->tail = item->prev;
+
+  if (item->prev)
+    item->prev->next = item->next;
+
+  if (item->next)
+    item->next->prev = item->prev;
+}
+
+static inline bool ll_removeData(struct ll * list, void * match)
+{
+  void * data;
+  ll_lock(list);
+  ll_forEachNL(list, item, data)
+    if (data == match)
+    {
+      ll_removeNL(list, item);
+      ll_unlock(list);
+      free(item);
+      return true;
+    }
+  ll_unlock(list);
+
+  return false;
+}
+
+#endif

common/src/ll.c

@@ -0,0 +1,119 @@
+/**
+ * Looking Glass
+ * Copyright © 2017-2022 The Looking Glass Authors
+ * https://looking-glass.io
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc., 59
+ * Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include "common/ll.h"
+#include "common/debug.h"
+#include "common/locking.h"
+#include <stdlib.h>
+
+struct ll * ll_new(void)
+{
+  struct ll * list = malloc(sizeof(*list));
+  list->head  = NULL;
+  list->tail  = NULL;
+  list->count = 0;
+  LG_LOCK_INIT(list->lock);
+  return list;
+}
+
+void ll_free(struct ll * list)
+{
+  // never free a list with items in it!
+  DEBUG_ASSERT(!list->head);
+
+  LG_LOCK_FREE(list->lock);
+  free(list);
+}
+
+void ll_push(struct ll * list, void * data)
+{
+  struct ll_item * item = malloc(sizeof(*item));
+  item->data = data;
+  item->next = NULL;
+
+  LG_LOCK(list->lock);
+  ++list->count;
+
+  if (!list->head)
+  {
+    item->prev = NULL;
+    list->head = item;
+    list->tail = item;
+    LG_UNLOCK(list->lock);
+    return;
+  }
+
+  item->prev = list->tail;
+
+  list->tail->next = item;
+  list->tail       = item;
+
+  LG_UNLOCK(list->lock);
+}
+
+bool ll_shift(struct ll * list, void ** data)
+{
+  LG_LOCK(list->lock);
+  if (!list->head)
+  {
+    LG_UNLOCK(list->lock);
+    return false;
+  }
+
+  struct ll_item * item = list->head;
+  ll_removeNL(list, item);
+  LG_UNLOCK(list->lock);
+
+  if (data)
+    *data = item->data;
+
+  free(item);
+  return true;
+}
+
+bool ll_peek_head(struct ll * list, void ** data)
+{
+  LG_LOCK(list->lock);
+  if (!list->head)
+  {
+    LG_UNLOCK(list->lock);
+    return false;
+  }
+
+  *data = list->head->data;
+  LG_UNLOCK(list->lock);
+
+  return true;
+}
+
+bool ll_peek_tail(struct ll * list, void ** data)
+{
+  LG_LOCK(list->lock);
+  if (!list->tail)
+  {
+    LG_UNLOCK(list->lock);
+    return false;
+  }
+
+  *data = list->tail->data;
+  LG_UNLOCK(list->lock);
+
+  return true;
+}