support/nfs/nfssvc.c

   1 /*
   2  * support/nfs/nfssvc.c
   3  *
   4  * Run an NFS daemon.
   5  *
   6  * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
   7  */
   8
   9 #ifdef HAVE_CONFIG_H
  10 #include <config.h>
  11 #endif
  12
  13 #include <unistd.h>
  14 #include <fcntl.h>
  15 #include <errno.h>
  16 #include <syslog.h>
  17
  18 #include "nfslib.h"
  19
  20 static void
  21 nfssvc_versbits(unsigned int ctlbits)
  22 {
  23         int fd, n, off;
  24         char buf[BUFSIZ], *ptr;
  25
  26         ptr = buf;
  27         off = 0;
  28         fd = open("/proc/fs/nfsd/versions", O_WRONLY);
  29         if (fd < 0)
  30                 return;
  31
  32         for (n = NFSD_MINVERS; n <= NFSD_MAXVERS; n++) {
  33                 if (NFSCTL_VERISSET(ctlbits, n))
  34                     off += snprintf(ptr+off, BUFSIZ - off, "+%d ", n);
  35                 else
  36                     off += snprintf(ptr+off, BUFSIZ - off, "-%d ", n);
  37         }
  38         snprintf(ptr+off, BUFSIZ - off, "\n");
  39         if (write(fd, buf, strlen(buf)) != strlen(buf)) {
  40                 syslog(LOG_ERR, "nfssvc: Setting version failed: errno %d (%s)",
  41                         errno, strerror(errno));
  42         }
  43         close(fd);
  44
  45         return;
  46 }
  47 int
  48 nfssvc(int port, int nrservs, unsigned int versbits)
  49 {
  50         struct nfsctl_arg       arg;
  51         int fd;
  52
  53         nfssvc_versbits(versbits);
  54
  55         fd = open("/proc/fs/nfsd/threads", O_WRONLY);
  56         if (fd < 0)
  57                 fd = open("/proc/fs/nfs/threads", O_WRONLY);
  58         if (fd >= 0) {
  59                 /* 2.5+ kernel with nfsd filesystem mounted.
  60                  * Just write the number in.
  61                  * Cannot handle port number yet, but does anyone care?
  62                  */
  63                 char buf[20];
  64                 int n;
  65                 snprintf(buf, 20,"%d\n", nrservs);
  66                 n = write(fd, buf, strlen(buf));
  67                 close(fd);
  68                 if (n != strlen(buf))
  69                         return -1;
  70                 else
  71                         return 0;
  72         }
  73
  74         arg.ca_version = NFSCTL_VERSION;
  75         arg.ca_svc.svc_nthreads = nrservs;
  76         arg.ca_svc.svc_port = port;
  77         return nfsctl(NFSCTL_SVC, &arg, NULL);
  78 }