2 This file is part of GNUnet.
3 (C) 2011, 2012 Christian Grothoff
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 3, or (at your
8 option) any later version.
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
22 * @file include/gnunet_helper_lib.h
23 * @brief API for dealing with (SUID) helper processes that communicate via GNUNET_MessageHeaders on stdin/stdout
24 * @author Philipp Toelke
25 * @author Christian Grothoff
27 #ifndef GNUNET_HELPER_LIB_H
28 #define GNUNET_HELPER_LIB_H
30 #include "gnunet_scheduler_lib.h"
31 #include "gnunet_server_lib.h"
34 * The handle to a helper process.
36 struct GNUNET_HELPER_Handle;
40 * @brief Starts a helper and begins reading from it
42 * @param binary_name name of the binary to run
43 * @param binary_argv NULL-terminated list of arguments to give when starting the binary (this
44 * argument must not be modified by the client for
45 * the lifetime of the helper handle)
46 * @param cb function to call if we get messages from the helper
47 * @param cb_cls Closure for the callback
48 * @return the new Handle, NULL on error
50 struct GNUNET_HELPER_Handle *
51 GNUNET_HELPER_start (const char *binary_name,
52 char *const binary_argv[],
53 GNUNET_SERVER_MessageTokenizerCallback cb, void *cb_cls);
57 * @brief Kills the helper, closes the pipe and frees the handle
59 * @param h handle to helper to stop
62 GNUNET_HELPER_stop (struct GNUNET_HELPER_Handle *h);
66 * Continuation function.
69 * @param result GNUNET_OK on success,
70 * GNUNET_NO if helper process died
71 * GNUNET_SYSERR during GNUNET_HELPER_stop
73 typedef void (*GNUNET_HELPER_Continuation)(void *cls,
78 * Send an message to the helper.
80 * @param h helper to send message to
81 * @param msg message to send
82 * @param can_drop can the message be dropped if there is already one in the queue?
83 * @param cont continuation to run once the message is out
84 * @param cont_cls closure for 'cont'
85 * @return GNUNET_YES if the message will be sent
86 * GNUNET_NO if the message was dropped
89 GNUNET_HELPER_send (struct GNUNET_HELPER_Handle *h,
90 const struct GNUNET_MessageHeader *msg,
92 GNUNET_HELPER_Continuation cont,
96 #endif /* end of include guard: GNUNET_HELPER_LIB_H */