Added a collect_posts handler

src/filters.h

@@ -61,6 +61,35 @@ public:
   virtual void operator()(post_t&) {}
 };
 
+class collect_posts : public item_handler<post_t>
+{
+public:
+  std::vector<post_t *> posts;
+
+  collect_posts() : item_handler<post_t>() {
+    TRACE_CTOR(collect_posts, "");
+  }
+  virtual ~collect_posts() {
+    TRACE_DTOR(collect_posts);
+  }
+
+  std::size_t length() const {
+    return posts.size();
+  }
+
+  std::vector<post_t *>::iterator begin() {
+    return posts.begin();
+  }
+  std::vector<post_t *>::iterator end() {
+    return posts.end();
+  }
+
+  virtual void flush() {}
+  virtual void operator()(post_t& post) {
+    posts.push_back(&post);
+  }
+};
+
 class posts_iterator;
 
 class pass_down_posts : public item_handler<post_t>