client/umount.cifs.c

ソースコードを見る。

関数
static void	umount_cifs_usage (void)
static int	umount_check_perm (char *dir)
static int	lock_mtab (void)
static void	unlock_mtab (void)
static int	remove_from_mtab (char *mountpoint)
int	main (int argc, char **argv)
変数
static struct option	longopts []
const char *	thisprogram
int	verboseflg = 0

---

関数

static void umount_cifs_usage

(

void

)

[static]

umount.cifs.c の 89 行で定義されています。

参照先 printf()・thisprogram.

参照元 main().

{
        printf("\nUsage:  %s <remotetarget> <dir>\n", thisprogram);
        printf("\nUnmount the specified directory\n");
        printf("\nLess commonly used options:");
        printf("\n\t-r\tIf mount fails, retry with readonly remount.");
        printf("\n\t-n\tDo not write to mtab.");
        printf("\n\t-f\tAttempt a forced unmount, even if the fs is busy.");
        printf("\n\t-l\tAttempt lazy unmount, Unmount now, cleanup later.");
        printf("\n\t-v\tEnable verbose mode (may be useful for debugging).");
        printf("\n\t-h\tDisplay this help.");
        printf("\n\nOptions are described in more detail in the manual page");
        printf("\n\tman 8 umount.cifs\n");
        printf("\nTo display the version number of the cifs umount utility:");
        printf("\n\t%s -V\n",thisprogram);
        printf("\nInvoking the umount utility on cifs mounts, can execute");
        printf(" /sbin/umount.cifs (if present and umount -i is not specified.\n");
}

static int umount_check_perm

(

char *

dir

)

[static]

umount.cifs.c の 108 行で定義されています。

参照先 errno・printf()・strerror()・thisprogram・verboseflg.

参照元 main().

{
        int fileid;
        int rc;

        /* allow root to unmount, no matter what */
        if(getuid() == 0)
                return 0;

        /* presumably can not chdir into the target as we do on mount */
        fileid = open(dir, O_RDONLY | O_DIRECTORY | O_NOFOLLOW, 0);
        if(fileid == -1) {
                if(verboseflg)
                        printf("error opening mountpoint %d %s",errno,strerror(errno));
                return errno;
        }

        rc = ioctl(fileid, CIFS_IOC_CHECKUMOUNT, NULL);

        if(verboseflg)
                printf("ioctl returned %d with errno %d %s\n",rc,errno,strerror(errno));

        if(rc == ENOTTY) {
                printf("user unmounting via %s is an optional feature of",thisprogram);
                printf(" the cifs filesystem driver (cifs.ko)");
                printf("\n\tand requires cifs.ko version 1.32 or later\n");
        } else if (rc != 0)
                printf("user unmount of %s failed with %d %s\n",dir,errno,strerror(errno));
        close(fileid);

        return rc;
}

static int lock_mtab

(

void

)

[static]

umount.cifs.c の 141 行で定義されています。

参照先 errno・printf()・strerror().

参照元 remove_from_mtab().

{
        int rc;
        
        rc = mknod(MOUNTED_LOCK , 0600, 0);
        if(rc == -1)
                printf("\ngetting lock file %s failed with %s\n",MOUNTED_LOCK,
                                strerror(errno));
                
        return rc;      
        
}

static void unlock_mtab

(

void

)

[static]

umount.cifs.c の 154 行で定義されています。

参照元 remove_from_mtab().

{
        unlink(MOUNTED_LOCK);   
}

static int remove_from_mtab

(

char *

mountpoint

)

[static]

umount.cifs.c の 159 行で定義されています。

参照先 errno・lock_mtab()・printf()・strerror()・unlock_mtab()・verboseflg.

参照元 main().

{
        int rc;
        int num_matches;
        FILE * org_fd;
        FILE * new_fd;
        struct mntent * mount_entry;

        /* Do we need to check if it is a symlink to e.g. /proc/mounts
        in which case we probably do not want to update it? */

        /* Do we first need to check if it is writable? */ 

        if (lock_mtab()) {
                printf("Mount table locked\n");
                return -EACCES;
        }
        
        if(verboseflg)
                printf("attempting to remove from mtab\n");

        org_fd = setmntent(MOUNTED, "r");

        if(org_fd == NULL) {
                printf("Can not open %s\n",MOUNTED);
                unlock_mtab();
                return -EIO;
        }

        new_fd = setmntent(MOUNTED_TEMP,"w");
        if(new_fd == NULL) {
                printf("Can not open temp file %s", MOUNTED_TEMP);
                endmntent(org_fd);
                unlock_mtab();
                return -EIO;
        }

        /* BB fix so we only remove the last entry that matches BB */
        num_matches = 0;
        while((mount_entry = getmntent(org_fd)) != NULL) {
                if(strcmp(mount_entry->mnt_dir, mountpoint) == 0) {
                        num_matches++;
                }
        }       
        if(verboseflg)
                printf("%d matching entries in mount table\n", num_matches);
                
        /* Is there a better way to seek back to the first entry in mtab? */
        endmntent(org_fd);
        org_fd = setmntent(MOUNTED, "r");

        if(org_fd == NULL) {
                printf("Can not open %s\n",MOUNTED);
                unlock_mtab();
                return -EIO;
        }
        
        while((mount_entry = getmntent(org_fd)) != NULL) {
                if(strcmp(mount_entry->mnt_dir, mountpoint) != 0) {
                        addmntent(new_fd, mount_entry);
                } else {
                        if(num_matches != 1) {
                                addmntent(new_fd, mount_entry);
                                num_matches--;
                        } else if(verboseflg)
                                printf("entry not copied (ie entry is removed)\n");
                }
        }

        if(verboseflg)
                printf("done updating tmp file\n");
        rc = fchmod (fileno (new_fd), S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH);
        if(rc < 0) {
                printf("error %s changing mode of %s\n", strerror(errno),
                        MOUNTED_TEMP);
        }
        endmntent(new_fd);

        rc = rename(MOUNTED_TEMP, MOUNTED);

        if(rc < 0) {
                printf("failure %s renaming %s to %s\n",strerror(errno),
                        MOUNTED_TEMP, MOUNTED);
                unlock_mtab();
                return -EIO;
        }

        unlock_mtab();
        
        return rc;
}

int main	(	int	argc,
		char **	argv
	)

umount.cifs.c の 251 行で定義されています。

参照先 c・errno・flags・longopts・optind・printf()・remove_from_mtab()・strerror()・thisprogram・umount_check_perm()・umount_cifs_usage()・verboseflg.

{
        int c;
        int rc;
        int flags = 0;
        int nomtab = 0;
        int retry_remount = 0;
        struct statfs statbuf;
        char * mountpoint;

        if(argc && argv) {
                thisprogram = argv[0];
        } else {
                umount_cifs_usage();
                return -EINVAL;
        }

        if(argc < 2) {
                umount_cifs_usage();
                return -EINVAL;
        }

        if(thisprogram == NULL)
                thisprogram = "umount.cifs";

        /* add sharename in opts string as unc= parm */

        while ((c = getopt_long (argc, argv, "afhilnrvV",
                         longopts, NULL)) != -1) {
                switch (c) {
/* No code to do the following  option yet */
/*              case 'a':              
                        ++umount_all;
                        break; */
                case '?':
                case 'h':   /* help */
                        umount_cifs_usage();
                        exit(1);
                case 'n':
                        ++nomtab;
                        break;
                case 'f':
                        flags |= MNT_FORCE;
                        break;
                case 'l':
                        flags |= MNT_DETACH; /* lazy unmount */
                        break;
                case 'e':
                        flags |= MNT_EXPIRE; /* gradually timeout */
                        break;
                case 'r':
                        ++retry_remount;
                        break;
                case 'v':
                        ++verboseflg;
                        break;
                case 'V':          
                        printf ("umount.cifs version: %s.%s%s\n",
                                UNMOUNT_CIFS_VERSION_MAJOR,
                                UNMOUNT_CIFS_VERSION_MINOR,
                                UNMOUNT_CIFS_VENDOR_SUFFIX);
                        exit (0);
                default:
                        printf("unknown unmount option %c\n",c);
                        umount_cifs_usage();
                        exit(1);
                }
        }

        /* move past the umount options */
        argv += optind;
        argc -= optind;

        mountpoint = argv[0];

        if((argc < 1) || (argv[0] == NULL)) {
                printf("\nMissing name of unmount directory\n");
                umount_cifs_usage();
                return -EINVAL;
        }

        if(verboseflg)
                printf("optind %d unmount dir %s\n",optind, mountpoint);

        /* check if running effectively root */
        if(geteuid() != 0) {
                printf("Trying to unmount when %s not installed suid\n",thisprogram);
                if(verboseflg)
                        printf("euid = %d\n",geteuid());
                return -EACCES;
        }

        /* fixup path if needed */

        /* Trim any trailing slashes */
        while ((strlen(mountpoint) > 1) &&
                (mountpoint[strlen(mountpoint)-1] == '/'))
        {
                mountpoint[strlen(mountpoint)-1] = '\0';
        }

        /* make sure that this is a cifs filesystem */
        rc = statfs(mountpoint, &statbuf);
        
        if(rc || (statbuf.f_type != CIFS_MAGIC_NUMBER)) {
                printf("This utility only unmounts cifs filesystems.\n");
                return -EINVAL;
        }

        /* check if our uid was the one who mounted */
        rc = umount_check_perm(mountpoint);
        if (rc) {
                printf("Not permitted to unmount\n");
                return rc;
        }

        if(umount2(mountpoint, flags)) {
        /* remember to kill daemon on error */
                switch (errno) {
                case 0:
                        printf("unmount failed but no error number set\n");
                        break;
                default:
                        printf("unmount error %d = %s\n",errno,strerror(errno));
                }
                printf("Refer to the umount.cifs(8) manual page (man 8 umount.cifs)\n");
                return -1;
        } else {
                if(verboseflg)
                        printf("umount2 succeeded\n");
                if(nomtab == 0)
                        remove_from_mtab(mountpoint);
        }

        return 0;
}

---

変数

struct option longopts[] [static]

初期値:

 {
        { "all", 0, NULL, 'a' },
        { "help",0, NULL, 'h' },
        { "read-only", 0, NULL, 'r' },
        { "ro", 0, NULL, 'r' },
        { "verbose", 0, NULL, 'v' },
        { "version", 0, NULL, 'V' },
        { "expire", 0, NULL, 'e' },
        { "force", 0, 0, 'f' },
        { "lazy", 0, 0, 'l' },
        { "no-mtab", 0, 0, 'n' },
        { NULL, 0, NULL, 0 }
}

umount.cifs.c の 72 行で定義されています。

const char* thisprogram

umount.cifs.c の 86 行で定義されています。

int verboseflg = 0

umount.cifs.c の 87 行で定義されています。

参照元 main()・remove_from_mtab()・umount_check_perm().

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