]> git.decadent.org.uk Git - nfs-utils.git/blobdiff - utils/nfsdcld/nfsdcld.c
nfsdcld: add client tracking daemon stub
[nfs-utils.git] / utils / nfsdcld / nfsdcld.c
diff --git a/utils/nfsdcld/nfsdcld.c b/utils/nfsdcld/nfsdcld.c
new file mode 100644 (file)
index 0000000..9fab2c3
--- /dev/null
@@ -0,0 +1,274 @@
+/*
+ * nfsdcld.c -- NFSv4 client name tracking daemon
+ *
+ * Copyright (C) 2011  Red Hat, Jeff Layton <jlayton@redhat.com>
+ *
+ * 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 Street, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif /* HAVE_CONFIG_H */
+
+#include <errno.h>
+#include <event.h>
+#include <stdbool.h>
+#include <getopt.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+#include "xlog.h"
+#include "nfslib.h"
+#include "cld.h"
+
+#ifndef PIPEFS_DIR
+#define PIPEFS_DIR NFS_STATEDIR "/rpc_pipefs"
+#endif
+
+#define DEFAULT_CLD_PATH       PIPEFS_DIR "/nfsd/cld"
+
+#define UPCALL_VERSION         1
+
+/* private data structures */
+struct cld_client {
+       int                     cl_fd;
+       struct event            cl_event;
+       struct cld_msg  cl_msg;
+};
+
+/* global variables */
+static char *pipepath = DEFAULT_CLD_PATH;
+
+static struct option longopts[] =
+{
+       { "help", 0, NULL, 'h' },
+       { "foreground", 0, NULL, 'F' },
+       { "debug", 0, NULL, 'd' },
+       { "pipe", 1, NULL, 'p' },
+       { NULL, 0, 0, 0 },
+};
+
+/* forward declarations */
+static void cldcb(int UNUSED(fd), short which, void *data);
+
+static void
+usage(char *progname)
+{
+       printf("Usage: %s [ -hFd ] [ -p pipe ]\n", progname);
+}
+
+static int
+cld_pipe_open(struct cld_client *clnt)
+{
+       int fd;
+
+       xlog(D_GENERAL, "%s: opening upcall pipe %s", __func__, pipepath);
+       fd = open(pipepath, O_RDWR, 0);
+       if (fd < 0) {
+               xlog(L_ERROR, "%s: open of %s failed: %m", __func__, pipepath);
+               return -errno;
+       }
+
+       if (clnt->cl_event.ev_flags & EVLIST_INIT)
+               event_del(&clnt->cl_event);
+       if (clnt->cl_fd >= 0)
+               close(clnt->cl_fd);
+
+       clnt->cl_fd = fd;
+       event_set(&clnt->cl_event, clnt->cl_fd, EV_READ, cldcb, clnt);
+       /* event_add is done by the caller */
+       return 0;
+}
+
+static int
+cld_pipe_init(struct cld_client *clnt)
+{
+       int ret;
+
+       clnt->cl_fd = -1;
+       ret = cld_pipe_open(clnt);
+       if (ret)
+               return ret;
+
+       event_add(&clnt->cl_event, NULL);
+       return 0;
+}
+
+static void
+cld_not_implemented(struct cld_client *clnt)
+{
+       int ret;
+       ssize_t bsize, wsize;
+       struct cld_msg *cmsg = &clnt->cl_msg;
+
+       xlog(D_GENERAL, "%s: downcalling with not implemented error", __func__);
+
+       /* set up reply */
+       cmsg->cm_status = -EOPNOTSUPP;
+
+       bsize = sizeof(*cmsg);
+
+       wsize = atomicio((void *)write, clnt->cl_fd, cmsg, bsize);
+       if (wsize != bsize)
+               xlog(L_ERROR, "%s: problem writing to cld pipe (%ld): %m",
+                        __func__, wsize);
+
+       /* reopen pipe, just to be sure */
+       ret = cld_pipe_open(clnt);
+       if (ret) {
+               xlog(L_FATAL, "%s: unable to reopen pipe: %d", __func__, ret);
+               exit(ret);
+       }
+}
+
+static void
+cld_create(struct cld_client *clnt)
+{
+       int ret;
+       ssize_t bsize, wsize;
+       struct cld_msg *cmsg = &clnt->cl_msg;
+
+       xlog(D_GENERAL, "%s: create client record", __func__);
+
+       /* FIXME: create client record on storage here */
+
+       /* set up reply */
+       cmsg->cm_status = 0;
+
+       bsize = sizeof(*cmsg);
+
+       wsize = atomicio((void *)write, clnt->cl_fd, cmsg, bsize);
+       if (wsize != bsize) {
+               xlog(L_ERROR, "%s: problem writing to cld pipe (%ld): %m",
+                        __func__, wsize);
+               ret = cld_pipe_open(clnt);
+               if (ret) {
+                       xlog(L_FATAL, "%s: unable to reopen pipe: %d",
+                                       __func__, ret);
+                       exit(ret);
+               }
+       }
+}
+
+static void
+cldcb(int UNUSED(fd), short which, void *data)
+{
+       ssize_t len;
+       struct cld_client *clnt = data;
+       struct cld_msg *cmsg = &clnt->cl_msg;
+
+       if (which != EV_READ)
+               goto out;
+
+       len = atomicio(read, clnt->cl_fd, cmsg, sizeof(*cmsg));
+       if (len <= 0) {
+               xlog(L_ERROR, "%s: pipe read failed: %m", __func__);
+               cld_pipe_open(clnt);
+               goto out;
+       }
+
+       if (cmsg->cm_vers != UPCALL_VERSION) {
+               xlog(L_ERROR, "%s: unsupported upcall version: %hu",
+                               cmsg->cm_vers);
+               cld_pipe_open(clnt);
+               goto out;
+       }
+
+       switch(cmsg->cm_cmd) {
+       case Cld_Create:
+               cld_create(clnt);
+               break;
+       default:
+               xlog(L_WARNING, "%s: command %u is not yet implemented",
+                               __func__, cmsg->cm_cmd);
+               cld_not_implemented(clnt);
+       }
+out:
+       event_add(&clnt->cl_event, NULL);
+}
+
+int
+main(int argc, char **argv)
+{
+       char arg;
+       int rc = 0;
+       bool foreground = false;
+       char *progname;
+       struct cld_client clnt;
+
+       memset(&clnt, 0, sizeof(clnt));
+
+       progname = strdup(basename(argv[0]));
+       if (!progname) {
+               fprintf(stderr, "%s: unable to allocate memory.\n", argv[0]);
+               return 1;
+       }
+
+       event_init();
+       xlog_syslog(0);
+       xlog_stderr(1);
+
+       /* process command-line options */
+       while ((arg = getopt_long(argc, argv, "hdFp:", longopts,
+                                 NULL)) != EOF) {
+               switch (arg) {
+               case 'd':
+                       xlog_config(D_ALL, 1);
+                       break;
+               case 'F':
+                       foreground = true;
+                       break;
+               case 'p':
+                       pipepath = optarg;
+                       break;
+               default:
+                       usage(progname);
+                       return 0;
+               }
+       }
+
+
+       xlog_open(progname);
+       if (!foreground) {
+               xlog_syslog(1);
+               xlog_stderr(0);
+               rc = daemon(0, 0);
+               if (rc) {
+                       xlog(L_ERROR, "Unable to daemonize: %m");
+                       goto out;
+               }
+       }
+
+       /* set up storage db */
+
+       /* set up event handler */
+       rc = cld_pipe_init(&clnt);
+       if (rc)
+               goto out;
+
+       xlog(D_GENERAL, "%s: Starting event dispatch handler.", __func__);
+       rc = event_dispatch();
+       if (rc < 0)
+               xlog(L_ERROR, "%s: event_dispatch failed: %m", __func__);
+
+       close(clnt.cl_fd);
+out:
+       free(progname);
+       return rc;
+}