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diff --git a/src/piper.looper.hh b/src/piper.looper.hh
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+/**
+ * Copyright (c) 2023, Timothy Stack
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ * * Neither the name of Timothy Stack nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ''AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef piper_looper_hh
+#define piper_looper_hh
+
+#include <future>
+#include <memory>
+#include <string>
+
+#include "base/auto_fd.hh"
+#include "base/piper.file.hh"
+#include "base/result.h"
+#include "ghc/filesystem.hpp"
+#include "yajlpp/yajlpp_def.hh"
+
+namespace lnav {
+namespace piper {
+
+enum class state {
+    running,
+    finished,
+};
+
+class looper {
+public:
+    looper(std::string name, auto_fd stdout_fd, auto_fd stderr_fd);
+
+    ~looper();
+
+    std::string get_name() const { return this->l_name; }
+
+    ghc::filesystem::path get_out_dir() const { return this->l_out_dir; }
+
+    ghc::filesystem::path get_out_pattern() const
+    {
+        return this->l_out_dir / "out.*";
+    }
+
+    std::string get_url() const
+    {
+        return fmt::format(FMT_STRING("piper://{}"),
+                           this->l_out_dir.filename().string());
+    }
+
+    bool is_finished() const
+    {
+        return this->l_future.wait_for(std::chrono::seconds(0))
+            == std::future_status::ready;
+    }
+
+    size_t consume_finished()
+    {
+        if (!this->is_finished()) {
+            return 0;
+        }
+
+        if (this->l_finished.fetch_or(1) == 0) {
+            return 1;
+        }
+        return 0;
+    }
+
+private:
+    void loop();
+
+    std::atomic<bool> l_looping{true};
+    const std::string l_name;
+    const std::string l_cwd;
+    const std::map<std::string, std::string> l_env;
+    ghc::filesystem::path l_out_dir;
+    auto_fd l_stdout;
+    auto_fd l_stderr;
+    std::future<void> l_future;
+    std::atomic<int> l_finished{0};
+};
+
+template<state LooperState>
+class handle {
+public:
+    explicit handle(std::shared_ptr<looper> looper)
+        : h_looper(std::move(looper))
+    {
+    }
+
+    std::string get_name() const { return this->h_looper->get_name(); }
+
+    ghc::filesystem::path get_out_dir() const
+    {
+        return this->h_looper->get_out_dir();
+    }
+
+    ghc::filesystem::path get_out_pattern() const
+    {
+        return this->h_looper->get_out_pattern();
+    }
+
+    std::string get_url() const { return this->h_looper->get_url(); }
+
+    bool is_finished() const { return this->h_looper->is_finished(); }
+
+    size_t consume_finished() { return this->h_looper->consume_finished(); }
+
+    bool operator==(const handle& other) const
+    {
+        return this->h_looper.get() == other.h_looper.get();
+    }
+
+private:
+    std::shared_ptr<looper> h_looper;
+};
+
+extern const typed_json_path_container<lnav::piper::header> header_handlers;
+
+using running_handle = handle<state::running>;
+
+Result<handle<state::running>, std::string> create_looper(std::string name,
+                                                          auto_fd stdout_fd,
+                                                          auto_fd stderr_fd);
+
+void cleanup();
+
+}  // namespace piper
+}  // namespace lnav
+
+#endif