support/export/xtab.c

   1 /*
   2  * support/export/xtab.c
   3  *
   4  * Interface to the xtab file.
   5  *
   6  * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
   7  */
   8
   9 #include "config.h"
  10
  11 #include <sys/fcntl.h>
  12 #include <unistd.h>
  13 #include <stdlib.h>
  14 #include <string.h>
  15 #include "xmalloc.h"
  16 #include "nfslib.h"
  17 #include "exportfs.h"
  18 #include "xio.h"
  19 #include "xlog.h"
  20
  21 static int
  22 xtab_read(char *xtab, int is_export)
  23 {
  24         struct exportent        *xp;
  25         nfs_export              *exp;
  26         int                     lockid;
  27
  28         if ((lockid = xflock(xtab, "r")) < 0)
  29                 return 0;
  30         setexportent(xtab, "r");
  31         while ((xp = getexportent()) != NULL) {
  32                 if (!(exp = export_lookup(xp->e_hostname, xp->e_path)) &&
  33                     !(exp = export_create(xp))) {
  34                         continue;
  35                 }
  36                 if (is_export) {
  37                         exp->m_xtabent = 1;
  38                         exp->m_mayexport = 1;
  39                 } else
  40                         exp->m_exported = 1;
  41         }
  42         endexportent();
  43         xfunlock(lockid);
  44
  45         return 0;
  46 }
  47
  48 int
  49 xtab_mount_read(void)
  50 {
  51         int fd;
  52         if ((fd=open(_PATH_PROC_EXPORTS, O_RDONLY))>=0) {
  53                 close(fd);
  54                 return xtab_read(_PATH_PROC_EXPORTS, 0);
  55         } else
  56                 return xtab_read(_PATH_XTAB, 0);
  57 }
  58
  59 int
  60 xtab_export_read(void)
  61 {
  62         return xtab_read(_PATH_ETAB, 1);
  63 }
  64
  65 static int
  66 xtab_write(char *xtab, char *xtabtmp, int is_export)
  67 {
  68         struct exportent        xe;
  69         nfs_export              *exp;
  70         int                     lockid, i;
  71
  72         if ((lockid = xflock(xtab, "w")) < 0) {
  73                 xlog(L_ERROR, "can't lock %s for writing", xtab);
  74                 return 0;
  75         }
  76         setexportent(xtabtmp, "w");
  77
  78         for (i = 0; i < MCL_MAXTYPES; i++) {
  79                 for (exp = exportlist[i]; exp; exp = exp->m_next) {
  80                         if (is_export && !exp->m_xtabent)
  81                                 continue;
  82                         if (!is_export && ! exp->m_exported)
  83                                 continue;
  84
  85                         /* write out the export entry using the FQDN */
  86                         xe = exp->m_export;
  87                         strncpy(xe.e_hostname,
  88                                 exp->m_client->m_hostname,
  89                                 sizeof (xe.e_hostname) - 1);
  90                         xe.e_hostname[sizeof (xe.e_hostname) - 1] = '\0';
  91                         putexportent(&xe);
  92                 }
  93         }
  94         endexportent();
  95
  96         rename(xtabtmp, xtab);
  97
  98         xfunlock(lockid);
  99
 100         return 1;
 101 }
 102
 103 int
 104 xtab_export_write()
 105 {
 106         return xtab_write(_PATH_ETAB, _PATH_ETABTMP, 1);
 107 }
 108
 109 int
 110 xtab_mount_write()
 111 {
 112         return xtab_write(_PATH_XTAB, _PATH_XTABTMP, 0);
 113 }
 114
 115 void
 116 xtab_append(nfs_export *exp)
 117 {
 118         struct exportent xe;
 119         int             lockid;
 120
 121         if ((lockid = xflock(_PATH_XTAB, "w")) < 0)
 122                 return;
 123         setexportent(_PATH_XTAB, "a");
 124         xe = exp->m_export;
 125         strncpy(xe.e_hostname, exp->m_client->m_hostname,
 126                sizeof (xe.e_hostname) - 1);
 127         xe.e_hostname[sizeof (xe.e_hostname) - 1] = '\0';
 128         putexportent(&xe);
 129         endexportent();
 130         xfunlock(lockid);
 131         exp->m_xtabent = 1;
 132 }
 133