umount.c

   1 #include "internal.h"
   2 #include <stdlib.h>
   3 #include <unistd.h>
   4 #include <errno.h>
   5 #include <string.h>
   6 #include <stdio.h>
   7 #include <mntent.h>
   8 #include <sys/mount.h>
   9
  10 const char      umount_usage[] = "umount {filesystem|directory}\n"
  11 "\tumount -a\n"
  12 "\n"
  13 "\tUnmount a filesystem.\n"
  14 "\t-a:\tUnmounts all mounted filesystems.\n";
  15
  16 static char *
  17 stralloc(const char * string)
  18 {
  19         int     length = strlen(string) + 1;
  20         char *  n = malloc(length);
  21         memcpy(n, string, length);
  22         return n;
  23 }
  24
  25 extern void
  26 erase_mtab(const char * name)
  27 {
  28         struct mntent   entries[100];
  29         int             count = 0;
  30         FILE *          mountTable = setmntent("/etc/mtab", "r");
  31         struct mntent * m;
  32
  33         if ( mountTable == 0
  34          && (mountTable = setmntent("/proc/mounts", "r")) == 0 ) {
  35                 name_and_error("/etc/mtab");
  36                 return;
  37         }
  38
  39         while ( (m = getmntent(mountTable)) != 0 ) {
  40                 entries[count].mnt_fsname = stralloc(m->mnt_fsname);
  41                 entries[count].mnt_dir = stralloc(m->mnt_dir);
  42                 entries[count].mnt_type = stralloc(m->mnt_type);
  43                 entries[count].mnt_opts = stralloc(m->mnt_opts);
  44                 entries[count].mnt_freq = m->mnt_freq;
  45                 entries[count].mnt_passno = m->mnt_passno;
  46                 count++;
  47         }
  48         endmntent(mountTable);
  49         if ( (mountTable = setmntent("/etc/mtab", "w")) ) {
  50                 int     i;
  51                 for ( i = 0; i < count; i++ ) {
  52                         int result = ( strcmp(entries[i].mnt_fsname, name) == 0
  53                          || strcmp(entries[i].mnt_dir, name) == 0 );
  54
  55                         if ( result )
  56                                 continue;
  57                         else
  58                                 addmntent(mountTable, &entries[i]);
  59                 }
  60                 endmntent(mountTable);
  61         }
  62         else if ( errno != EROFS )
  63                 name_and_error("/etc/mtab");
  64 }
  65
  66 static int
  67 umount_all(int noMtab)
  68 {
  69         struct mntent   entries[100];
  70         int                             count = 0;
  71         FILE *                  mountTable = setmntent("/etc/mtab", "r");
  72         struct mntent * m;
  73         int                             status = 0;
  74
  75         if ( mountTable == 0
  76          && (mountTable = setmntent("/proc/mounts", "r")) == 0 ) {
  77                 name_and_error("/etc/mtab");
  78                 return 1;
  79         }
  80
  81         while ( (m = getmntent(mountTable)) != 0 ) {
  82                 entries[count].mnt_fsname = stralloc(m->mnt_fsname);
  83                 count++;
  84         }
  85         endmntent(mountTable);
  86
  87         while ( count > 0 ) {
  88                 int result = umount(entries[--count].mnt_fsname) == 0;
  89                 /* free(entries[count].mnt_fsname); */
  90                 if ( result ) {
  91                         if ( !noMtab )
  92                                 erase_mtab(entries[count].mnt_fsname);
  93                 }
  94                 else {
  95                         status = 1;
  96                         name_and_error(entries[count].mnt_fsname);
  97                 }
  98         }
  99         return status;
 100 }
 101
 102 extern int
 103 do_umount(const char * name, int noMtab)
 104 {
 105         if ( umount(name) == 0 ) {
 106                 if ( !noMtab )
 107                         erase_mtab(name);
 108                 return 0;
 109         }
 110         return 1;
 111 }
 112
 113 extern int
 114 umount_main(struct FileInfo * i, int argc, char * * argv)
 115 {
 116         int     noMtab = 0;
 117
 118         if ( argv[1][0] == '-' ) {
 119                 switch ( argv[1][1] ) {
 120                 case 'a':
 121                         return umount_all(noMtab);
 122                 case 'n':
 123                         noMtab = 1;
 124                         break;
 125                 default:
 126                         usage(umount_usage);
 127                         return 1;
 128                 }
 129         }
 130         if ( do_umount(argv[1],noMtab) != 0 ) {
 131                 fprintf(stderr, "%s: %s.\n", argv[1], strerror(errno));
 132                 return 1;
 133         }
 134         return 0;
 135 }