1 files changed, 220 insertions, 0 deletions
diff --git a/src/common/admin_socket.h b/src/common/admin_socket.h
new file mode 100644
index 000000000..c5d2b48e5
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+++ b/src/common/admin_socket.h
@@ -0,0 +1,220 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+/*
+ * Ceph - scalable distributed file system
+ *
+ * Copyright (C) 2011 New Dream Network
+ *
+ * This is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License version 2.1, as published by the Free Software
+ * Foundation.  See file COPYING.
+ *
+ */
+
+#ifndef CEPH_COMMON_ADMIN_SOCKET_H
+#define CEPH_COMMON_ADMIN_SOCKET_H
+
+#if defined(WITH_SEASTAR) && !defined(WITH_ALIEN)
+#include "crimson/admin/admin_socket.h"
+#else
+
+#include <condition_variable>
+#include <mutex>
+#include <string>
+#include <string_view>
+#include <thread>
+
+#include "include/buffer.h"
+#include "include/common_fwd.h"
+#include "common/ref.h"
+#include "common/cmdparse.h"
+
+class MCommand;
+class MMonCommand;
+
+inline constexpr auto CEPH_ADMIN_SOCK_VERSION = std::string_view("2");
+
+class AdminSocketHook {
+public:
+  /**
+   * @brief
+   * Handler for admin socket commands, synchronous version
+   *
+   * Executes action associated with admin command and returns byte-stream output @c out.
+   * There is no restriction on output. Each handler defines output semantics.
+   * Typically output is textual representation of some ceph's internals.
+   * Handler should use provided formatter @c f if structuralized output is being produced.
+   *
+   * @param command[in] String matching constant part of cmddesc in @ref AdminSocket::register_command
+   * @param cmdmap[in]  Parameters extracted from argument part of cmddesc in @ref AdminSocket::register_command
+   * @param f[in]       Formatter created according to requestor preference, used by `ceph --format`
+   * @param errss[out]  Error stream, should contain details in case of execution failure
+   * @param out[out]    Produced output
+   *
+   * @retval 0 Success, errss is ignored and does not contribute to output
+   * @retval <0 Error code, errss is prepended to @c out
+   *
+   * @note If @c out is empty, then admin socket will try to flush @c f to out.
+   */
+  virtual int call(
+    std::string_view command,
+    const cmdmap_t& cmdmap,
+    ceph::Formatter *f,
+    std::ostream& errss,
+    ceph::buffer::list& out) = 0;
+
+  /**
+   * @brief
+   * Handler for admin socket commands, asynchronous version
+   *
+   * Executes action associated with admin command and prepares byte-stream response.
+   * When processing is done @c on_finish must be called.
+   * There is no restriction on output. Each handler defines own output semantics.
+   * Typically output is textual representation of some ceph's internals.
+   * Input @c inbl can be passed, see ceph --in-file.
+   * Handler should use provided formatter @c f if structuralized output is being produced.
+   * on_finish handler has following parameters:
+   * - result code of handler (same as @ref AdminSocketHook::call)
+   * - error message, text
+   * - output
+   *
+   * @param[in] command String matching constant part of cmddesc in @ref AdminSocket::register_command
+   * @param[in] cmdmap  Parameters extracted from argument part of cmddesc in @ref AdminSocket::register_command
+   * @param[in] f       Formatter created according to requestor preference, used by `ceph --format`
+   * @param[in] inbl    Input content for handler
+   * @param[in] on_finish Function to call when processing is done
+   *
+   * @note If @c out is empty, then admin socket will try to flush @c f to out.
+   */
+  virtual void call_async(
+    std::string_view command,
+    const cmdmap_t& cmdmap,
+    ceph::Formatter *f,
+    const ceph::buffer::list& inbl,
+    std::function<void(int,const std::string&,ceph::buffer::list&)> on_finish) {
+    // by default, call the synchronous handler and then finish
+    ceph::buffer::list out;
+    std::ostringstream errss;
+    int r = call(command, cmdmap, f, errss, out);
+    on_finish(r, errss.str(), out);
+  }
+  virtual ~AdminSocketHook() {}
+};
+
+class AdminSocket
+{
+public:
+  AdminSocket(CephContext *cct);
+  ~AdminSocket();
+
+  AdminSocket(const AdminSocket&) = delete;
+  AdminSocket& operator =(const AdminSocket&) = delete;
+  AdminSocket(AdminSocket&&) = delete;
+  AdminSocket& operator =(AdminSocket&&) = delete;
+
+  /**
+   * register an admin socket command
+   *
+   * The command is registered under a command string.  Incoming
+   * commands are split by space and matched against the longest
+   * registered command.  For example, if 'foo' and 'foo bar' are
+   * registered, and an incoming command is 'foo bar baz', it is
+   * matched with 'foo bar', while 'foo fud' will match 'foo'.
+   *
+   * The entire incoming command string is passed to the registered
+   * hook.
+   *
+   * @param command command string
+   * @param cmddesc command syntax descriptor
+   * @param hook implementation
+   * @param help help text.  if empty, command will not be included in 'help' output.
+   *
+   * @return 0 for success, -EEXIST if command already registered.
+   */
+  int register_command(std::string_view cmddesc,
+		       AdminSocketHook *hook,
+		       std::string_view help);
+
+  /*
+   * unregister all commands belong to hook.
+   */
+  void unregister_commands(const AdminSocketHook *hook);
+
+  bool init(const std::string& path);
+
+  void chown(uid_t uid, gid_t gid);
+  void chmod(mode_t mode);
+
+  /// execute (async)
+  void execute_command(
+    const std::vector<std::string>& cmd,
+    const ceph::buffer::list& inbl,
+    std::function<void(int,const std::string&,ceph::buffer::list&)> on_fin);
+
+  /// execute (blocking)
+  int execute_command(
+    const std::vector<std::string>& cmd,
+    const ceph::buffer::list& inbl,
+    std::ostream& errss,
+    ceph::buffer::list *outbl);
+
+  void queue_tell_command(ceph::cref_t<MCommand> m);
+  void queue_tell_command(ceph::cref_t<MMonCommand> m); // for compat
+
+private:
+
+  void shutdown();
+  void wakeup();
+
+  std::string create_wakeup_pipe(int *pipe_rd, int *pipe_wr);
+  std::string destroy_wakeup_pipe();
+  std::string bind_and_listen(const std::string &sock_path, int *fd);
+
+  std::thread th;
+  void entry() noexcept;
+  void do_accept();
+  void do_tell_queue();
+
+  CephContext *m_cct;
+  std::string m_path;
+  int m_sock_fd = -1;
+  int m_wakeup_rd_fd = -1;
+  int m_wakeup_wr_fd = -1;
+  bool m_shutdown = false;
+
+  bool in_hook = false;
+  std::condition_variable in_hook_cond;
+  std::mutex lock;  // protects `hooks`
+  std::unique_ptr<AdminSocketHook> version_hook;
+  std::unique_ptr<AdminSocketHook> help_hook;
+  std::unique_ptr<AdminSocketHook> getdescs_hook;
+
+  std::mutex tell_lock;
+  std::list<ceph::cref_t<MCommand>> tell_queue;
+  std::list<ceph::cref_t<MMonCommand>> tell_legacy_queue;
+
+  struct hook_info {
+    AdminSocketHook* hook;
+    std::string desc;
+    std::string help;
+
+    hook_info(AdminSocketHook* hook, std::string_view desc,
+	      std::string_view help)
+      : hook(hook), desc(desc), help(help) {}
+  };
+
+  /// find the first hook which matches the given prefix and cmdmap
+  std::pair<int, AdminSocketHook*> find_matched_hook(
+    std::string& prefix,
+    const cmdmap_t& cmdmap);
+
+  std::multimap<std::string, hook_info, std::less<>> hooks;
+
+  friend class AdminSocketTest;
+  friend class HelpHook;
+  friend class GetdescsHook;
+};
+
+#endif
+#endif