date and time created 80/10/01 17:29:08 by bill

[unix-history] / usr / src / sbin / umount / umount.c

static char *sccsid = "@(#)umount.c     4.1 (Berkeley) %G%";
#include <stdio.h>
#include <fstab.h>
/*
*      umount name
*
*      umount -a
*              This tries to unmount all of the block special file names
*              as given in /etc/fstab.
*/

#define NMOUNT  16
#define NAMSIZ  32

struct mtab {
       char    file[NAMSIZ];
       char    spec[NAMSIZ];
} mtab[NMOUNT];

main(argc, argv)
char **argv;
{
       register struct mtab *mp;
       register char *p1, *p2;
       int mf;

       sync();
       mf = open("/etc/mtab", 0);
       read(mf, (char *)mtab, NMOUNT*2*NAMSIZ);
       if(argc != 2) {
               printf("arg count\n");
               return(1);
       }
       if (strcmp(argv[1], "-a") == 0){
               FILE    *fs_file;
               struct  fstab   fs;
               if ( (fs_file = fopen(FSTAB, "r")) == NULL){
                       perror(FSTAB);
                       exit(1);
               }
               while (!feof(fs_file)){
                       fscanf(fs_file, FSTABFMT, FSTABARG(&fs));
                       if (strcmp(fs.fs_file, "/") == 0)
                               continue;
                       fprintf(stderr, "Unmounting special file %s\n",
                               fs.fs_spec);
                       fflush(stderr);
                       if (umountfs(fs.fs_spec))
                               continue;
               }
               fclose(fs_file);
       } else {
               if (umountfs(argv[1]))
                       exit(1);
       }
       exit(0);
}

int umountfs(name)
       char    *name;
{
       register        char    *p1, *p2;
       register        struct  mtab    *mp;
       int     mf;

       if (umount(name) < 0) {
               perror("umount");
               return(1);
       }
       p1 = name;
       while(*p1++)
               ;
       p1--;
       while(*--p1 == '/')
               *p1 = '\0';
       while(p1 > name && *--p1 != '/')
               ;
       if(*p1 == '/')
               p1++;
       name = p1;
       for (mp = mtab; mp < &mtab[NMOUNT]; mp++) {
               p1 = name;
               p2 = &mp->spec[0];
               while (*p1++ == *p2)
                       if (*p2++ == 0) {
                               for (p1 = mp->file; p1 < &mp->file[NAMSIZ*2];)
                                       *p1++ = 0;
                               mp = &mtab[NMOUNT];
                               while ((--mp)->file[0] == 0);
                               mf = creat("/etc/mtab", 0644);
                               write(mf, (char *)mtab, (mp-mtab+1)*2*NAMSIZ);
                               return(0);
                       }
       }
       printf("%s not in mount table\n", name);
       return(1);
}