proto_detail_file.c

Go to the documentation of this file.

/*
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
 */
 
/**
 * $Id: 48de2d484e66a4bb7c1b0282f458fbc2b43bbb6b $
 * @file proto_detail_file.c
 * @brief Detail handler for files
 *
 * @copyright 2017 The FreeRADIUS server project.
 * @copyright 2017 Alan DeKok (aland@deployingradius.com)
 */
 
#include <freeradius-devel/io/application.h>
#include <freeradius-devel/io/listen.h>
#include <freeradius-devel/io/schedule.h>
 
#include <freeradius-devel/server/main_config.h>
 
#include <freeradius-devel/util/syserror.h>
#include <freeradius-devel/util/misc.h>
 
#include "proto_detail.h"
 
#include <netdb.h>
 
#include <fcntl.h>
#include <sys/stat.h>
 
#ifdef HAVE_GLOB_H
#include <glob.h>
#else
#error proto_detail_file requires <glob.h>
#endif
 
DIAG_OFF(unused-macros)
#if 0
/*
 *      When we want detailed debugging here, without detailed server
 *      debugging.
 */
#define MPRINT DEBUG
#else
#define MPRINT DEBUG3
#endif
DIAG_ON(unused-macros)
 
/*
 *      For talloc names, ".name = detail_file", and dl.c prepends "proto_", and appends "_t".
 */
typedef struct proto_detail_work_s proto_detail_file_t;
 
/*
 *      @todo - this should really now be a different data structure
 */
typedef struct proto_detail_work_thread_s proto_detail_file_thread_t;
 
static void work_init(proto_detail_file_thread_t *thread, bool triggered_by_delete);
static void mod_vnode_delete(fr_event_list_t *el, int fd, UNUSED int fflags, void *ctx);
 
static const conf_parser_t file_listen_config[] = {
        { FR_CONF_OFFSET_FLAGS("filename", CONF_FLAG_REQUIRED, proto_detail_file_t, filename ) },
 
        { FR_CONF_OFFSET("filename_work", proto_detail_file_t, filename_work ) },
 
        { FR_CONF_OFFSET("poll_interval", proto_detail_file_t, poll_interval), .dflt = "5" },
 
        { FR_CONF_OFFSET("immediate", proto_detail_file_t, immediate) },
 
        CONF_PARSER_TERMINATOR
};
 
 
/*
 *      All of the decoding is done by proto_detail and proto_detail_work
 */
static int mod_decode(void const *instance, request_t *request, uint8_t *const data, size_t data_len)
{
        proto_detail_file_t const       *inst = talloc_get_type_abort_const(instance, proto_detail_file_t);
 
        return inst->parent->work_io->decode(inst->parent->work_io_instance, request, data, data_len);
}
 
#if 0
static ssize_t mod_write(UNUSED fr_listen_t *li, UNUSED void *packet_ctx, UNUSED fr_time_t request_time,
                         UNUSED uint8_t *buffer, UNUSED size_t buffer_len, UNUSED size_t written)
{
#if 1
        fr_assert(0);
 
        return -1;
#else
        proto_detail_file_thread_t  *thread = talloc_get_type_abort(li->thread_instance, proto_detail_file_thread_t);
 
        return thread->listen->app_io->write(thread->listen, packet_ctx, request_time, buffer, buffer_len, written);
#endif
}
#endif
 
static void mod_vnode_extend(fr_listen_t *li, UNUSED uint32_t fflags)
{
        proto_detail_file_thread_t *thread = talloc_get_type_abort(li->thread_instance, proto_detail_file_thread_t);
 
        bool has_worker = false;
 
        pthread_mutex_lock(&thread->worker_mutex);
        has_worker = (thread->num_workers != 0);
        pthread_mutex_unlock(&thread->worker_mutex);
 
        if (has_worker) return;
 
        FR_TIMER_DISARM(thread->ev);
 
        work_init(thread, false);
}
 
/** Open a detail listener
 *
 */
static int mod_open(fr_listen_t *li)
{
        proto_detail_file_t const  *inst = talloc_get_type_abort_const(li->app_io_instance, proto_detail_file_t);
        proto_detail_file_thread_t *thread = talloc_get_type_abort(li->thread_instance, proto_detail_file_thread_t);
 
        if (inst->poll_interval == 0) {
                int oflag;
 
#ifdef O_EVTONLY
                oflag = O_EVTONLY;
#else
                oflag = O_RDONLY;
#endif
                li->fd = thread->fd = open(inst->directory, oflag);
                if (thread->fd < 0) {
                        cf_log_err(inst->cs, "Failed opening %s: %s", inst->directory, fr_syserror(errno));
                        return -1;
                }
        } else {
                li->fd = thread->fd = -1;
                li->non_socket_listener = true;
                li->needs_full_setup = true;
        }
        thread->inst = inst;
        thread->name = talloc_typed_asprintf(thread, "detail_file which will read files matching %s", inst->filename);
        thread->vnode_fd = -1;
        pthread_mutex_init(&thread->worker_mutex, NULL);
 
        li->no_write_callback = true;
 
        return 0;
}
 
/*
 *      The "detail.work" file doesn't exist.  Let's see if we can rename one.
 */
static int work_rename(proto_detail_file_thread_t *thread)
{
        proto_detail_file_t const *inst = thread->inst;
        unsigned int    i;
        int             found;
        time_t          chtime;
        char const      *filename;
        glob_t          files;
        struct stat     st;
 
        DEBUG3("proto_detail (%s): polling for detail files in %s",
               thread->name, inst->directory);
 
        memset(&files, 0, sizeof(files));
        if (glob(inst->filename, 0, NULL, &files) != 0) {
        noop:
                DEBUG3("proto_detail (%s): no matching files for %s",
                       thread->name, inst->filename);
                globfree(&files);
                return -1;
        }
 
        /*
         *      Loop over the glob'd files, looking for the
         *      oldest one.
         */
        chtime = 0;
        found = -1;
        for (i = 0; i < files.gl_pathc; i++) {
                if (stat(files.gl_pathv[i], &st) < 0) continue;
 
                if ((i == 0) || (st.st_ctime < chtime)) {
                        chtime = st.st_ctime;
                        found = i;
                }
        }
 
        /*
         *      No matching files, reset the timer and continue.
         */
        if (found < 0) goto noop;
 
        /*
         *      Rename detail to detail.work
         */
        filename = files.gl_pathv[found];
 
        DEBUG("proto_detail (%s): Renaming %s -> %s", thread->name, filename, inst->filename_work);
        if (rename(filename, inst->filename_work) < 0) {
                ERROR("detail (%s): Failed renaming %s to %s: %s",
                      thread->name, filename, inst->filename_work, fr_syserror(errno));
                goto noop;
        }
 
        globfree(&files);       /* Shouldn't be using anything in files now */
 
        /*
         *      The file should now exist, return the open'd FD.
         */
        return open(inst->filename_work, inst->mode);
}
 
/*
 *      Start polling again after a timeout.
 */
static void work_retry_timer(UNUSED fr_timer_list_t *tl, UNUSED fr_time_t now, void *uctx)
{
        proto_detail_file_thread_t *thread = talloc_get_type_abort(uctx, proto_detail_file_thread_t);
 
        work_init(thread, false);
}
 
/*
 *      The "detail.work" file exists, and is open in the 'fd'.
 */
static int work_exists(proto_detail_file_thread_t *thread, int fd)
{
        proto_detail_file_t const *inst = thread->inst;
        bool                    opened = false;
        proto_detail_work_thread_t     *work;
        fr_listen_t             *li = NULL;
        struct stat             st;
 
        fr_event_vnode_func_t   funcs = { .delete = mod_vnode_delete };
 
        DEBUG3("proto_detail (%s): Trying to lock %s", thread->name, inst->filename_work);
 
        /*
         *      "detail.work" exists, try to lock it.
         */
        if (rad_lockfd_nonblock(fd, 0) < 0) {
                fr_time_delta_t delay;
 
                DEBUG3("proto_detail (%s): Failed locking %s: %s",
                       thread->name, inst->filename_work, fr_syserror(errno));
 
                close(fd);
 
                delay = thread->lock_interval;
 
                /*
                 *      Set the next interval, and ensure that we
                 *      don't do massive busy-polling.
                 */
                thread->lock_interval = fr_time_delta_add(thread->lock_interval,
                                                          fr_time_delta_div(thread->lock_interval,
                                                                            fr_time_delta_wrap(2)));
                if (fr_time_delta_gt(thread->lock_interval, fr_time_delta_from_sec(30))) {
                        thread->lock_interval = fr_time_delta_from_sec(30);
                }
 
                DEBUG3("proto_detail (%s): Waiting %.6fs for lock on file %s",
                       thread->name, fr_time_delta_unwrap(delay) / (double)NSEC, inst->filename_work);
 
                if (fr_timer_in(thread, thread->el->tl, &thread->ev, delay,
                                false, work_retry_timer, thread) < 0) {
                        ERROR("Failed inserting retry timer for %s", inst->filename_work);
                }
                return 0;
        }
 
        DEBUG3("proto_detail (%s): Obtained lock and starting to process file %s",
               thread->name, inst->filename_work);
 
        /*
         *      Ignore empty files.
         */
        if (fstat(fd, &st) < 0) {
                ERROR("Failed opening %s: %s", inst->filename_work,
                      fr_syserror(errno));
                unlink(inst->filename_work);
                close(fd);
                return 1;
        }
 
        if (!st.st_size) {
                DEBUG3("proto_detail (%s): %s file is empty, ignoring it.",
                       thread->name, inst->filename_work);
                unlink(inst->filename_work);
                close(fd);
                return 1;
        }
 
        /*
         *      This listener is allocated in a thread-specific
         *      context, so it doesn't need a destructor,
         */
        MEM(li = talloc_zero(NULL, fr_listen_t));
 
        /*
         *      Create a new listener, and insert it into the
         *      scheduler.  Shamelessly copied from proto_detail.c
         *      mod_open(), with changes.
         *
         *      This listener is parented from the worker.  So that
         *      when the worker goes away, so does the listener.
         */
        li->cs = inst->parent->work_io_conf;
        li->app_io = inst->parent->work_io;
 
        li->app = inst->parent->self;
        li->app_instance = inst->parent;
        li->server_cs = inst->parent->server_cs;
 
        /*
         *      The worker may be in a different thread, so avoid
         *      talloc threading issues by using a NULL TALLOC_CTX.
         */
        MEM(li->thread_instance = work = talloc_zero(li, proto_detail_work_thread_t));
 
        li->app_io_instance = inst->parent->work_io_instance;
        work->inst = li->app_io_instance;
        work->file_parent = thread;
        work->ev = NULL;
 
        li->fd = work->fd = dup(fd);
        if (work->fd < 0) {
                DEBUG("proto_detail (%s): Failed opening %s: %s",
                      thread->name, inst->filename_work, fr_syserror(errno));
 
                close(fd);
                talloc_free(li);
                return -1;
        }
 
        /*
         *      Don't do anything until the file has been deleted.
         *
         *      @todo - ensure that proto_detail_work is done the file...
         *      maybe by creating a new instance?
         */
        if (fr_event_filter_insert(thread, NULL, thread->el, fd, FR_EVENT_FILTER_VNODE,
                                   &funcs, NULL, thread) < 0) {
                PERROR("Failed adding work socket to event loop");
                close(li->fd);
                close(fd);
                talloc_free(li);
                return -1;
        }
 
        /*
         *      Remember this for later.
         */
        thread->vnode_fd = fd;
 
        /*
         *      For us, this is the worker listener.
         *      For the worker, this is it's own parent
         */
        thread->listen = li;
 
        work->filename_work = talloc_strdup(work, inst->filename_work);
 
        /*
         *      Set configurable parameters for message ring buffer.
         */
        li->default_message_size = inst->parent->max_packet_size;
        li->num_messages = inst->parent->num_messages;
 
        /*
         *      Open the detail.work file.
         */
        if (li->app_io->open(li) < 0) {
                ERROR("Failed opening %s", li->app_io->common.name);
                goto error;
        }
        opened = true;
 
        fr_assert(li->app_io->get_name);
        li->name = li->app_io->get_name(li);
 
        if (!fr_schedule_listen_add(inst->parent->sc, li)) {
        error:
                if (fr_event_fd_delete(thread->el, thread->vnode_fd, FR_EVENT_FILTER_VNODE) < 0) {
                        PERROR("Failed removing DELETE callback when opening work file");
                }
                close(thread->vnode_fd);
                thread->vnode_fd = -1;
 
                if (opened) {
                        (void) li->app_io->close(li);
                        thread->listen = NULL;
                        li = NULL;
                } else {
                        close(li->fd);
                }
 
                talloc_free(li);
                return -1;
        }
 
        /*
         *      Tell the worker to clean itself up.
         */
        work->listen = li;
 
        pthread_mutex_lock(&thread->worker_mutex);
        thread->num_workers++;
        pthread_mutex_unlock(&thread->worker_mutex);
 
        return 0;
}
 
 
static void mod_vnode_delete(fr_event_list_t *el, int fd, UNUSED int fflags, void *ctx)
{
        proto_detail_file_thread_t *thread = talloc_get_type_abort(ctx, proto_detail_file_thread_t);
        proto_detail_file_t const *inst = thread->inst;
 
        DEBUG("proto_detail (%s): Deleted %s", thread->name, inst->filename_work);
 
        /*
         *      Silently ignore notifications from the directory.  We
         *      didn't ask for them, but libkqueue delivers them to
         *      us.
         */
        if (fd == thread->fd) return;
 
        if (fd != thread->vnode_fd) {
                ERROR("Received DELETE for FD %d, when we were expecting one on FD %d - ignoring it",
                      fd, thread->vnode_fd);
                return;
        }
 
        if (fr_event_fd_delete(el, fd, FR_EVENT_FILTER_VNODE) < 0) {
                PERROR("Failed removing DELETE callback after deletion");
        }
        close(fd);
        thread->vnode_fd = -1;
 
        /*
         *      Re-initialize the state machine.
         *
         *      Note that a "delete" may be the result of an atomic
         *      "move", which both deletes the old file, and creates
         *      the new one.
         */
        work_init(thread, true);
}
 
 
/** Start processing a new work file
 *
 * @param[in] thread                    the thread instance.
 * @param[in] triggered_by_delete       true if this was triggered by a vnode_delete.
 *                                      When a new file is moved over a workfile
 *                                      vnode delete can serve as an indication
 *                                      that new data is available.
 *                                      It can also mean however, that the file
 *                                      has just been deleted, so we shouldn't
 *                                      treat this failure to open the new file
 *                                      as a fatal error.
 */
static void work_init(proto_detail_file_thread_t *thread, bool triggered_by_delete)
{
        proto_detail_file_t const *inst = thread->inst;
        int fd, rcode;
        bool has_worker;
 
        pthread_mutex_lock(&thread->worker_mutex);
        has_worker = (thread->num_workers != 0);
        pthread_mutex_unlock(&thread->worker_mutex);
 
        /*
         *      The worker is still processing the file, poll until
         *      it's done.
         */
        if (has_worker) {
                DEBUG3("proto_detail (%s): worker %s is still alive, waiting for it to finish.",
                       thread->name, inst->filename_work);
                goto delay;
        }
 
        fr_assert(thread->vnode_fd < 0);
 
        /*
         *      See if there is a "detail.work" file.  If not, try to
         *      rename an existing file to "detail.work".
         */
        DEBUG3("Trying to open %s", inst->filename_work);
        fd = open(inst->filename_work, inst->mode);
 
        /*
         *      If the work file didn't exist, try to rename detail* ->
         *      detail.work, and return the newly opened file.
         */
        if (fd < 0) {
                if (errno != ENOENT) {
                        DEBUG("proto_detail (%s): Failed opening %s: %s",
                              thread->name, inst->filename_work,
                              fr_syserror(errno));
                        goto delay;
                }
 
retry:
                fd = work_rename(thread);
        }
 
        /*
         *      The work file still doesn't exist.  Go set up timers,
         *      or wait for an event which signals us that something
         *      in the directory changed.
         */
        if (fd < 0) {
                /*
                 *      Wait for the directory to change before
                 *      looking for another "detail" file.
                 */
                if (!inst->poll_interval) return;
 
                /*
                 *      File really was deleted, and didn't have
                 *      anything moved over the top.
                 */
                if (inst->immediate && triggered_by_delete) return;
 
delay:
                /*
                 *      If we're processing one file and exiting, then the input file must exist.
                 */
                if (inst->immediate && inst->parent->exit_when_done) {
                        ERROR("Input file does not exist");
                        fr_exit(EXIT_FAILURE);
                }
 
                /*
                 *      Check every N seconds.
                 */
                DEBUG3("Waiting %d.000000s for new files in %s", inst->poll_interval, thread->name);
 
                if (fr_timer_in(thread, thread->el->tl, &thread->ev,
                                fr_time_delta_from_sec(inst->poll_interval),
                                false, work_retry_timer, thread) < 0) {
                        ERROR("Failed inserting poll timer for %s", inst->filename_work);
                }
                return;
        }
 
        thread->lock_interval = fr_time_delta_from_msec(100);
 
        /*
         *      It exists, go process it!
         *
         *      We will get back to the main loop when the
         *      "detail.work" file is deleted.
         */
        rcode = work_exists(thread, fd);
        if (rcode < 0) goto delay;
 
        /*
         *      The file was empty, so we try to get another one.
         */
        if (rcode == 1) goto retry;
 
        /*
         *      Otherwise the child is successfully processing the
         *      file.
         */
}
 
 
/** Set the event list for a new IO instance
 *
 * @param[in] li the listener
 * @param[in] el the event list
 * @param[in] nr context from the network side
 */
static void mod_event_list_set(fr_listen_t *li, fr_event_list_t *el, UNUSED void *nr)
{
        proto_detail_file_t const  *inst = talloc_get_type_abort_const(li->app_io_instance, proto_detail_file_t);
        proto_detail_file_thread_t *thread = talloc_get_type_abort(li->thread_instance, proto_detail_file_thread_t);
 
        thread->el = el;
 
        if (inst->immediate) {
                work_init(thread, false);
                return;
        }
 
        /*
         *      Delay for a bit, before reading the detail files.
         *      This gives the server time to call
         *      rad_suid_down_permanent(), and for /proc/PID to
         *      therefore change permissions, so that libkqueue can
         *      read it.
         */
        if (fr_timer_in(thread, thread->el->tl, &thread->ev,
                        fr_time_delta_from_sec(1), false, work_retry_timer, thread) < 0) {
                ERROR("Failed inserting poll timer for %s", inst->filename_work);
        }
}
 
 
static char const *mod_name(fr_listen_t *li)
{
        proto_detail_file_thread_t *thread = talloc_get_type_abort(li->thread_instance, proto_detail_file_thread_t);
 
        return thread->name;
}
 
 
static fr_rb_tree_t *detail_file_tree = NULL;
static pthread_mutex_t detail_file_mutex = PTHREAD_MUTEX_INITIALIZER;
 
/** Compare two thread instances based on node pointer
 *
 * @param[in] one       First thread specific xlat expansion instance.
 * @param[in] two       Second thread specific xlat expansion instance.
 * @return CMP(one, two)
 */
static fr_cmp_ret_t _detail_file_cmp(void const *one, void const *two)
{
        proto_detail_file_t const *a = one, *b = two;
 
        return CMP(strcmp(a->filename, b->filename), 0);
}
 
/*
 *      Check for multiple readers on the same set of files.
 */
static int mod_instantiate(module_inst_ctx_t const *mctx)
{
        proto_detail_file_t     *inst = talloc_get_type_abort(mctx->mi->data, proto_detail_file_t);
        CONF_SECTION            *conf = mctx->mi->conf;
 
        module_instance_t const *mi;
        char                    *p;
 
#ifdef __linux__
        /*
         *      The kqueue API takes an FD, but inotify requires a filename.
         *      libkqueue uses /proc/PID/fd/# to look up the FD -> filename mapping.
         *
         *      However, if you start the server as "root", and then swap to "radiusd",
         *      /proc/PID will be owned by "root" for security reasons.  The only way
         *      to make /proc/PID owned by "radiusd" is to set the DUMPABLE flag.
         *
         *      Instead of making the poor sysadmin figure this out,
         *      we check for this situation, and give them a
         *      descriptive message telling them what to do.
         */
        if (!main_config->allow_core_dumps &&
            main_config->uid_is_set &&
            main_config->server_uid != 0) {
                cf_log_err(conf, "Cannot start detail file reader due to Linux limitations.");
                cf_log_err(conf, "Please set 'allow_core_dumps = true' in the main configuration file.");
                return -1;
        }
#endif
 
        /*
         *      Find the module_instance_t holding our instance data
         *      so we can find out what the parent of our instance
         *      was.
         */
        mi = mctx->mi;
 
#ifndef __linux__
        /*
         *      Linux inotify works.  So we allow poll_interval==0
         */
        FR_INTEGER_BOUND_CHECK("poll_interval", inst->poll_interval, >=, 1);
#endif
        FR_INTEGER_BOUND_CHECK("poll_interval", inst->poll_interval, <=, 3600);
 
        inst->parent = talloc_get_type_abort(mi->parent->data, proto_detail_t);
        inst->cs = conf;
 
        inst->directory = p = talloc_strdup(inst, inst->filename);
 
        p = strrchr(p, '/');
        if (!p) {
                cf_log_err(conf, "Filename must contain '/'");
                return -1;
        }
 
        *p = '\0';
 
        if (!inst->filename_work) {
                inst->filename_work = talloc_typed_asprintf(inst, "%s/detail.work", inst->directory);
        }
 
        /*
         *      We need this for the lock.
         */
        inst->mode = O_RDWR;
 
        if (inst->parent->exit_when_done && !inst->immediate) {
                cf_log_warn(conf, "Ignoring 'exit_when_done' due to 'immediate' flag not being set");
                inst->parent->exit_when_done = false;
        }
 
        pthread_mutex_lock(&detail_file_mutex);
        if (!detail_file_tree) {
                detail_file_tree = fr_rb_inline_talloc_alloc(conf, proto_detail_file_t, filename_node, _detail_file_cmp, NULL);
                if (!detail_file_tree) {
                        pthread_mutex_unlock(&detail_file_mutex);
                        cf_log_err(conf, "Failed initializing detail_file");
                        return -1;
                }
        }
 
        if (fr_rb_insert(detail_file_tree, inst) != 0) {
                proto_detail_file_t *old;
 
                fr_rb_find((void **)&old, detail_file_tree, inst);
                fr_assert(old);
 
                pthread_mutex_unlock(&detail_file_mutex);
                cf_log_err(conf, "Duplicate detail listener %s", inst->filename);
                cf_log_err(conf, "Original detail listener is in virtual server %s", cf_section_name2(old->parent->server_cs));
                return -1;
        }
        pthread_mutex_unlock(&detail_file_mutex);
 
        return 0;
}
 
 
static int mod_close(fr_listen_t *li)
{
        proto_detail_file_t const  *inst = talloc_get_type_abort_const(li->app_io_instance, proto_detail_file_t);
        proto_detail_file_thread_t *thread = talloc_get_type_abort(li->thread_instance, proto_detail_file_thread_t);
 
        if (thread->nr) {
                if (unlikely(fr_network_listen_delete(thread->nr, inst->parent->listen) < 0)) {
                        PERROR("Failed removing listener from network on detach");
                }
        }
 
        /*
         *      @todo - have our OWN event loop for timers, and a
         *      "copy timer from -> to, which means we only have to
         *      delete our child event loop from the parent on close.
         */
        if (thread->fd >= 0) close(thread->fd);
 
        if (thread->vnode_fd >= 0) {
                if (thread->nr) {
                        if (unlikely(fr_network_listen_delete(thread->nr, inst->parent->listen) < 0)) {
                                PERROR("Failed removing listener from network on detach");
                        }
                } else {
                        if (fr_event_fd_delete(thread->el, thread->vnode_fd, FR_EVENT_FILTER_VNODE) < 0) {
                                PERROR("Failed removing DELETE callback on detach");
                        }
                }
                close(thread->vnode_fd);
                thread->vnode_fd = -1;
        }
 
        pthread_mutex_destroy(&thread->worker_mutex);
 
        return 0;
}
 
 
/** Private interface for use by proto_detail_file
 *
 */
extern fr_app_io_t proto_detail_file;
fr_app_io_t proto_detail_file = {
        .common = {
                .magic                  = MODULE_MAGIC_INIT,
                .name                   = "detail_file",
                .config                 = file_listen_config,
                .inst_size              = sizeof(proto_detail_file_t),
                .thread_inst_size       = sizeof(proto_detail_file_thread_t),
                .instantiate            = mod_instantiate,
        },
        .default_message_size   = 65536,
        .default_reply_size     = 32,
 
        .open                   = mod_open,
        .close                  = mod_close,
        .vnode                  = mod_vnode_extend,
        .decode                 = mod_decode,
//      .write                  = mod_write,
        .event_list_set         = mod_event_list_set,
        .get_name               = mod_name,
};