r7202: lock mtab when updating it during umount.cifs, also delete only one matching...

diff --git a/source/client/umount.cifs.c b/source/client/umount.cifs.c
index 88a9776b04822423fbdad8ead44e34dea14ffa6f..3a6c1aa9566b4db6909a2fd6ceed306062ff0680 100644 (file)
--- a/source/client/umount.cifs.c
+++ b/source/client/umount.cifs.c
@@ -37,7 +37,7 @@
 #include <fstab.h>
 
 #define UNMOUNT_CIFS_VERSION_MAJOR "0"
-#define UNMOUNT_CIFS_VERSION_MINOR "4"
+#define UNMOUNT_CIFS_VERSION_MINOR "5"
 
 #ifndef UNMOUNT_CIFS_VENDOR_SUFFIX
 #define UNMOUNT_CIFS_VENDOR_SUFFIX ""
@@ -93,7 +93,8 @@ static void umount_cifs_usage(void)
        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("\nNote that invoking the umount utility on cifs mounts, can execute /sbin/umount.cifs (if it is present and -i is not specified to umount).\n");
+       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)
@@ -118,18 +119,39 @@ static int umount_check_perm(char * dir)
        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 the cifs filesystem driver (cifs.ko)\n\tand requires cifs.ko version 1.32 or later\n",thisprogram);
-       else if (rc > 0)
+       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;
 }
 
+int lock_mtab(void)
+{
+       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;      
+       
+}
+
+void unlock_mtab(void)
+{
+       unlink(MOUNTED_LOCK);   
+}
+
 int remove_from_mtab(char * mountpoint)
 {
-       int rc = 0;
+       int rc;
+       int num_matches;
        FILE * org_fd;
        FILE * new_fd;
        struct mntent * mount_entry;
@@ -139,11 +161,11 @@ int remove_from_mtab(char * mountpoint)
 
        /* Do we first need to check if it is writable? */ 
 
-       /* BB lock_mtab - the smbumount and mount-utils package appear to lock 
-       in a different incompat. way, and it seems that mount-utils have
-       changed the way they lock a few times. We should fix this someday
-       or at least find out how the mount-utils are supposed to handle this */
-
+       if (lock_mtab()) {
+               printf("Mount table locked\n");
+               return -EACCES;
+       }
+       
        if(verboseflg)
                printf("attempting to remove from mtab\n");
 
@@ -151,6 +173,7 @@ int remove_from_mtab(char * mountpoint)
 
        if(org_fd == NULL) {
                printf("Can not open %s\n",MOUNTED);
+               unlock_mtab();
                return -EIO;
        }
 
@@ -158,18 +181,40 @@ int remove_from_mtab(char * mountpoint)
        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(verboseflg)
-                               printf("entry not copied (removed)\n");
+                       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)
@@ -186,10 +231,11 @@ int remove_from_mtab(char * mountpoint)
        if(rc < 0) {
                printf("failure %s renaming %s to %s\n",strerror(errno),
                        MOUNTED_TEMP, MOUNTED);
+               unlock_mtab();
                return -EIO;
        }
 
-       /* BB unlock_mtab - unlink(MOUNTED_LOCK) */
+       unlock_mtab();
        
        return rc;
 }
@@ -292,7 +338,7 @@ int main(int argc, char ** argv)
        rc = statfs(mountpoint, &statbuf);
        
        if(rc || (statbuf.f_type != CIFS_MAGIC_NUMBER)) {
-               printf("Wrong filesystem. This utility only unmounts cifs filesystems.\n");
+               printf("This utility only unmounts cifs filesystems.\n");
                return -EINVAL;
        }
 
@@ -312,7 +358,7 @@ int main(int argc, char ** argv)
                default:
                        printf("unmount error %d = %s\n",errno,strerror(errno));
                }
-               printf("Refer to the umount.cifs(8) manual page (e.g.man 8 umount.cifs)\n");
+               printf("Refer to the umount.cifs(8) manual page (man 8 umount.cifs)\n");
                return -1;
        } else {
                if(verboseflg)