Add session pool

src/session/session_pool.cpp

@@ -0,0 +1,66 @@
+#include "session_pool.h"
+
+struct session_pool
+{
+    uint64_t count;
+    struct session *sess;
+};
+
+struct session_pool *session_pool_create(uint64_t count)
+{
+    struct session_pool *pool = (struct session_pool *)calloc(1, sizeof(struct session_pool) + count * sizeof(struct session));
+    if (pool == NULL)
+    {
+        return NULL;
+    }
+
+    pool->count = count;
+    pool->sess = (struct session *)(pool + 1);
+
+    for (uint64_t i = 0; i < count; i++)
+    {
+        pool->sess[i].next = &pool->sess[i + 1];
+    }
+    pool->sess[count - 1].next = NULL;
+
+    return pool;
+}
+
+void session_pool_destroy(struct session_pool *pool)
+{
+    if (pool)
+    {
+        free(pool);
+        pool = NULL;
+    }
+}
+
+struct session *session_pool_pop(struct session_pool *pool)
+{
+    if (pool == NULL)
+    {
+        return NULL;
+    }
+
+    struct session *sess = pool->sess;
+    if (sess == NULL)
+    {
+        return NULL;
+    }
+
+    pool->sess = sess->next;
+    sess->next = NULL;
+
+    return sess;
+}
+
+void session_pool_push(struct session_pool *pool, struct session *sess)
+{
+    if (pool == NULL || sess == NULL)
+    {
+        return;
+    }
+
+    sess->next = pool->sess;
+    pool->sess = sess;
+}