libmount: add support for userdata and work with VFS tree

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/shlibs/mount/src/fs.c b/shlibs/mount/src/fs.c
index fef61b0d680e05fc696786dc217fb5a99dbc0ac1..ae97b65420d8312d9b0ad6aa78dc89e7851f5c95 100644 (file)
--- a/shlibs/mount/src/fs.c
+++ b/shlibs/mount/src/fs.c
@@ -57,6 +57,33 @@ void mnt_free_fs(mnt_fs *fs)
        free(fs);
 }
 
+/**
+ * mnt_fs_get_userdata:
+ * @fs: mnt_file instance
+ *
+ * Returns private data set by mnt_fs_set_userdata() or NULL.
+ */
+void *mnt_fs_get_userdata(mnt_fs *fs)
+{
+       return fs ? fs->userdata : NULL;
+}
+
+/**
+ * mnt_fs_set_userdata:
+ * @fs: mnt_file instance
+ *
+ * The "userdata" are library independent data.
+ *
+ * Returns 0 or -1 in case of error (if @fs is NULL).
+ */
+int mnt_fs_set_userdata(mnt_fs *fs, void *data)
+{
+       if (!fs)
+               return -1;
+       fs->userdata = data;
+       return 0;
+}
+
 /**
  * mnt_fs_get_srcpath:
  * @fs: mnt_file (fstab/mtab/mountinfo) fs

diff --git a/shlibs/mount/src/mount.h.in b/shlibs/mount/src/mount.h.in
index 585b9fca3c6d73d7aee3651c2377a4452e91104a..4e918b8332ba846534a4a24095bbf2cff7c3e455 100644 (file)
--- a/shlibs/mount/src/mount.h.in
+++ b/shlibs/mount/src/mount.h.in
@@ -212,6 +212,8 @@ extern int mnt_lock_file(mnt_lock *ml);
 /* fs.c */
 extern mnt_fs *mnt_new_fs(void);
 extern void mnt_free_fs(mnt_fs *ent);
+extern void *mnt_fs_get_userdata(mnt_fs *fs);
+extern int mnt_fs_set_userdata(mnt_fs *fs, void *data);
 extern const char *mnt_fs_get_source(mnt_fs *ent);
 extern int mnt_fs_set_source(mnt_fs *ent, const char *source);
 extern const char *mnt_fs_get_srcpath(mnt_fs *ent);
@@ -271,6 +273,9 @@ extern const char *mnt_tab_get_name(mnt_tab *tb);
 extern int mnt_tab_add_fs(mnt_tab *tb, mnt_fs *fs);
 extern int mnt_tab_remove_fs(mnt_tab *tb, mnt_fs *fs);
 extern int mnt_tab_next_fs(mnt_tab *tb, mnt_iter *itr, mnt_fs **fs);
+extern int mnt_tab_next_child_fs(mnt_tab *tb, mnt_iter *itr,
+                               mnt_fs *parent, mnt_fs **chld);
+extern int mnt_tab_get_root_fs(mnt_tab *tb, mnt_fs **root);
 extern int mnt_tab_set_iter(mnt_tab *tb, mnt_iter *itr, mnt_fs *fs);
 
 extern mnt_fs *mnt_tab_find_target(mnt_tab *tb, const char *path, int direction);

diff --git a/shlibs/mount/src/mount.sym b/shlibs/mount/src/mount.sym
index 6740bbcd366da57a08718792080c8d1a7b3a9e91..5df37796a6835ef7afcf3f8d61ee946cac437957 100644 (file)
--- a/shlibs/mount/src/mount.sym
+++ b/shlibs/mount/src/mount.sym
@@ -31,6 +31,7 @@ global:
        mnt_fs_get_srcpath;
        mnt_fs_get_tag;
        mnt_fs_get_target;
+       mnt_fs_get_userdata;
        mnt_fs_match_fstype;
        mnt_fs_match_options;
        mnt_fs_match_source;
@@ -42,6 +43,7 @@ global:
        mnt_fs_set_passno;
        mnt_fs_set_source;
        mnt_fs_set_target;
+       mnt_fs_set_userdata;
        mnt_fstype_is_netfs;
        mnt_fstype_is_pseudofs;
        mnt_get_builtin_optmap;
@@ -116,6 +118,8 @@ global:
        mnt_tab_get_name;
        mnt_tab_get_nents;
        mnt_tab_get_nerrs;
+       mnt_tab_get_root_fs;
+       mnt_tab_next_child_fs;
        mnt_tab_next_fs;
        mnt_tab_parse_file;
        mnt_tab_remove_fs;

diff --git a/shlibs/mount/src/mountP.h b/shlibs/mount/src/mountP.h
index e92ba701aa22d2d19f29190c922f390be39e058a..4b4e5b5b5e35c614cc7a948c3e12f4028697ba0b 100644 (file)
--- a/shlibs/mount/src/mountP.h
+++ b/shlibs/mount/src/mountP.h
@@ -155,6 +155,8 @@ struct _mnt_fs {
 
        int             flags;          /* MNT_FS_* flags */
        int             lineno;         /* line number in the parental file */
+
+       void            *userdata;      /* library independent data */
 };
 
 /*

diff --git a/shlibs/mount/src/tab.c b/shlibs/mount/src/tab.c
index 2ae694b5ede9cef398a7b54b05aadb4fafb38532..98c56602b8d7327f2f6bcecc20341c443ea61db0 100644 (file)
--- a/shlibs/mount/src/tab.c
+++ b/shlibs/mount/src/tab.c
@@ -209,6 +209,97 @@ int mnt_tab_remove_fs(mnt_tab *tb, mnt_fs *fs)
        return 0;
 }
 
+/**
+ * mnt_tab_get_root_fs:
+ * @tb: mountinfo file (/proc/self/mountinfo)
+ * @root: returns pointer to the root filesystem (/)
+ *
+ * Returns: 0 on success or -1 case of error.
+ */
+int mnt_tab_get_root_fs(mnt_tab *tb, mnt_fs **root)
+{
+       mnt_iter itr;
+       mnt_fs *fs;
+       int root_id = 0;
+
+       assert(tb);
+       assert(root);
+
+       if (!tb || !root)
+               return -1;
+
+       mnt_reset_iter(&itr, MNT_ITER_FORWARD);
+       while(mnt_tab_next_fs(tb, &itr, &fs) == 0) {
+               int id = mnt_fs_get_parent_id(fs);
+               if (!id)
+                       break;          /* @tab is not mountinfo file? */
+
+               if (!*root || id < root_id) {
+                       *root = fs;
+                       root_id = id;
+               }
+       }
+
+       return root_id ? 0 : -1;
+}
+
+/**
+ * mnt_tab_next_child_fs:
+ * @tb: mountinfo file (/proc/self/mountinfo)
+ * @parent: parental FS
+ * @chld: returns the next child filesystem
+ *
+ * Note that filesystems are returned in the order how was mounted (according to
+ * IDs in /proc/self/mountinfo).
+ *
+ * Returns 0 on success, -1 in case of error or 1 at end of list.
+ */
+int mnt_tab_next_child_fs(mnt_tab *tb, mnt_iter *itr,
+                       mnt_fs *parent, mnt_fs **chld)
+{
+       mnt_fs *fs;
+       int parent_id, lastchld_id = 0, chld_id = 0;
+
+       if (!tb || !itr || !parent)
+               return -1;
+
+       parent_id = mnt_fs_get_id(parent);
+       if (!parent_id)
+               return -1;
+
+       /* get ID of the previously returned child */
+       if (itr->head && itr->p != itr->head) {
+               MNT_ITER_ITERATE(itr, fs, struct _mnt_fs, ents);
+               lastchld_id = mnt_fs_get_id(fs);
+       }
+
+       *chld = NULL;
+
+       mnt_reset_iter(itr, MNT_ITER_FORWARD);
+       while(mnt_tab_next_fs(tb, itr, &fs) == 0) {
+               int id;
+
+               if (mnt_fs_get_parent_id(fs) != parent_id)
+                       continue;
+
+               id = mnt_fs_get_id(fs);
+
+               if ((!lastchld_id || id > lastchld_id) &&
+                   (!*chld || id < chld_id)) {
+                       *chld = fs;
+                       chld_id = id;
+               }
+       }
+
+       if (!chld_id)
+               return 1;       /* end of iterator */
+
+       /* set the iterator to the @chld for the next call */
+       mnt_tab_set_iter(tb, itr, *chld);
+
+       return 0;
+}
+
 /**
  * mnt_tab_next_fs:
  * @tb: tab pointer
@@ -290,6 +381,7 @@ int mnt_tab_find_next_fs(mnt_tab *tb, mnt_iter *itr,
                        return 0;
        } while(1);
 
+       *fs = NULL;
        return 1;
 }