X-Git-Url: https://scm.lunaixsky.com/lunaix-os.git/blobdiff_plain/d8d001a6664b88b66524989589fcd809de6d3a92..bc34fd00d2e81fbc890bb2060ed6693454a230bf:/lunaix-os/kernel/fs/vfs.c

diff --git a/lunaix-os/kernel/fs/vfs.c b/lunaix-os/kernel/fs/vfs.c
index f09a701..68a8d5f 100644
--- a/lunaix-os/kernel/fs/vfs.c
+++ b/lunaix-os/kernel/fs/vfs.c
@@ -72,6 +72,7 @@ vfs_init()
     // 创建一个根superblock，用来蕴含我们的根目录。
     root_sb = vfs_sb_alloc();
     root_sb->root = vfs_d_alloc();
+    root_sb->root->inode = vfs_i_alloc();
 }
 
 inline struct hbucket*
@@ -228,7 +229,7 @@ vfs_walk(struct v_dnode* start,
          int options)
 {
     struct v_dnode* interim;
-    char* pathname = path;
+    const char* pathname = path;
     int errno = __vfs_walk(start, path, &interim, component, options);
     int counter = 0;
 
@@ -237,7 +238,7 @@ vfs_walk(struct v_dnode* start,
             errno = ELOOP;
             continue;
         }
-        if ((interim->inode->itype & VFS_INODE_TYPE_SYMLINK) &&
+        if ((interim->inode->itype & VFS_IFSYMLINK) &&
             !(options & VFS_WALK_NOFOLLOW) &&
             interim->inode->ops.read_symlink) {
             errno = interim->inode->ops.read_symlink(interim->inode, &pathname);
@@ -262,7 +263,7 @@ vfs_mount(const char* target, const char* fs_name, bdev_t device)
     int errno;
     struct v_dnode* mnt;
 
-    if (!(errno = vfs_walk(NULL, target, &mnt, NULL, 0))) {
+    if (!(errno = vfs_walk(__current->cwd, target, &mnt, NULL, 0))) {
         errno = vfs_mount_at(fs_name, device, mnt);
     }
 
@@ -275,7 +276,7 @@ vfs_unmount(const char* target)
     int errno;
     struct v_dnode* mnt;
 
-    if (!(errno = vfs_walk(NULL, target, &mnt, NULL, 0))) {
+    if (!(errno = vfs_walk(__current->cwd, target, &mnt, NULL, 0))) {
         errno = vfs_unmount_at(mnt);
     }
 
@@ -327,27 +328,31 @@ vfs_open(struct v_dnode* dnode, struct v_file** file)
         return ENOTSUP;
     }
 
+    struct v_inode* inode = dnode->inode;
     struct v_file* vfile = cake_grab(file_pile);
     memset(vfile, 0, sizeof(*vfile));
 
     vfile->dnode = dnode;
-    vfile->inode = dnode->inode;
+    vfile->inode = inode;
     vfile->ref_count = 1;
-    dnode->inode->open_count++;
+    vfile->ops = inode->default_fops;
 
-    if ((dnode->inode->itype & VFS_INODE_TYPE_FILE) &&
-        !dnode->inode->pg_cache) {
+    if ((inode->itype & VFS_IFFILE) && !inode->pg_cache) {
         struct pcache* pcache = vzalloc(sizeof(struct pcache));
         pcache_init(pcache);
-        dnode->inode->pg_cache = pcache;
+        pcache->master = inode;
+        inode->pg_cache = pcache;
     }
 
-    int errno = dnode->inode->ops.open(dnode->inode, vfile);
+    int errno = inode->ops.open(inode, vfile);
     if (errno) {
         cake_release(file_pile, vfile);
     } else {
+        dnode->ref_count++;
+        inode->open_count++;
         *file = vfile;
     }
+
     return errno;
 }
 
@@ -372,10 +377,9 @@ vfs_close(struct v_file* file)
 {
     int errno = 0;
     if (!file->ops.close || !(errno = file->ops.close(file))) {
-        if (file->inode->open_count) {
-            file->inode->open_count--;
-        }
-        pcache_commit_all(file);
+        file->dnode->ref_count--;
+        file->inode->open_count--;
+        pcache_commit_all(file->inode);
         cake_release(file_pile, file);
     }
     return errno;
@@ -385,11 +389,9 @@ int
 vfs_fsync(struct v_file* file)
 {
     int errno = ENOTSUP;
+    pcache_commit_all(file->inode);
     if (file->ops.sync) {
-        errno = file->ops.sync(file);
-    }
-    if (!errno && file->inode->ops.sync) {
-        return file->inode->ops.sync(file->inode);
+        errno = file->ops.sync(file->inode);
     }
     return errno;
 }
@@ -459,6 +461,18 @@ vfs_i_free(struct v_inode* inode)
 #define FLOCATE_CREATE_EMPTY 1
 
 #define DO_STATUS(errno) SYSCALL_ESTATUS(__current->k_status = errno)
+#define DO_STATUS_OR_RETURN(errno) ({ errno < 0 ? DO_STATUS(errno) : errno; })
+
+#define TEST_FD(fd) (fd >= 0 && fd < VFS_MAX_FD)
+
+int
+__vfs_getfd(int fd, struct v_fd** fd_s)
+{
+    if (TEST_FD(fd) && (*fd_s = __current->fdtable->fds[fd])) {
+        return 0;
+    }
+    return EBADF;
+}
 
 int
 __vfs_try_locate_file(const char* path,
@@ -469,7 +483,8 @@ __vfs_try_locate_file(const char* path,
     char name_str[VFS_NAME_MAXLEN];
     struct hstr name = HSTR(name_str, 0);
     int errno;
-    if ((errno = vfs_walk(NULL, path, fdir, &name, VFS_WALK_PARENT))) {
+    if ((errno =
+           vfs_walk(__current->cwd, path, fdir, &name, VFS_WALK_PARENT))) {
         return errno;
     }
 
@@ -492,11 +507,11 @@ __vfs_try_locate_file(const char* path,
 }
 
 int
-__vfs_do_open(struct v_file** file_out, const char* path, int options)
+vfs_do_open(const char* path, int options)
 {
-    int errno;
+    int errno, fd;
     struct v_dnode *dentry, *file;
-    struct v_file* opened_file = 0;
+    struct v_file* ofile = 0;
 
     errno = __vfs_try_locate_file(path, &dentry, &file, 0);
 
@@ -504,40 +519,40 @@ __vfs_do_open(struct v_file** file_out, const char* path, int options)
         errno = dentry->inode->ops.create(dentry->inode);
     }
 
-    if (!errno) {
-        errno = vfs_open(file, &opened_file);
+    if (!errno && (errno = vfs_open(file, &ofile))) {
+        return errno;
     }
 
-    *file_out = opened_file;
-    return errno;
-}
-
-__DEFINE_LXSYSCALL2(int, open, const char*, path, int, options)
-{
-    struct v_file* opened_file;
-    int errno = __vfs_do_open(&opened_file, path, options), fd;
+    struct v_inode* o_inode = ofile->inode;
+    if (!(o_inode->itype & VFS_IFSEQDEV) && !(options & FO_DIRECT)) {
+        // XXX Change here accordingly when signature of pcache_r/w changed.
+        ofile->ops.read = pcache_read;
+        ofile->ops.write = pcache_write;
+    }
 
     if (!errno && !(errno = vfs_alloc_fdslot(&fd))) {
         struct v_fd* fd_s = vzalloc(sizeof(*fd_s));
-        opened_file->f_pos =
-          opened_file->inode->fsize & -((options & FO_APPEND) != 0);
-        fd_s->file = opened_file;
+        ofile->f_pos = ofile->inode->fsize & -((options & FO_APPEND) != 0);
+        fd_s->file = ofile;
         fd_s->flags = options;
         __current->fdtable->fds[fd] = fd_s;
         return fd;
     }
 
-    return DO_STATUS(errno);
+    return errno;
+}
+
+__DEFINE_LXSYSCALL2(int, open, const char*, path, int, options)
+{
+    int errno = vfs_do_open(path, options);
+    return DO_STATUS_OR_RETURN(errno);
 }
-#define TEST_FD(fd) (fd >= 0 && fd < VFS_MAX_FD)
-#define GET_FD(fd, fd_s) (TEST_FD(fd) && (fd_s = __current->fdtable->fds[fd]))
 
 __DEFINE_LXSYSCALL1(int, close, int, fd)
 {
     struct v_fd* fd_s;
     int errno = 0;
-    if (!GET_FD(fd, fd_s)) {
-        errno = EBADF;
+    if ((errno = __vfs_getfd(fd, &fd_s))) {
         goto done_err;
     }
 
@@ -570,9 +585,12 @@ __DEFINE_LXSYSCALL2(int, readdir, int, fd, struct dirent*, dent)
 {
     struct v_fd* fd_s;
     int errno;
-    if (!GET_FD(fd, fd_s)) {
-        errno = EBADF;
-    } else if (!(fd_s->file->inode->itype & VFS_INODE_TYPE_DIR)) {
+
+    if ((errno = __vfs_getfd(fd, &fd_s))) {
+        goto done;
+    }
+
+    if (!(fd_s->file->inode->itype & VFS_IFDIR)) {
         errno = ENOTDIR;
     } else {
         struct dir_context dctx =
@@ -586,7 +604,7 @@ __DEFINE_LXSYSCALL2(int, readdir, int, fd, struct dirent*, dent)
             __vfs_readdir_callback(&dctx, vfs_ddot.value, vfs_ddot.len, 0);
         } else {
             dctx.index -= 2;
-            if ((errno = fd_s->file->ops.readdir(fd_s->file, &dctx))) {
+            if ((errno = fd_s->file->ops.readdir(fd_s->file->inode, &dctx))) {
                 goto done;
             }
         }
@@ -602,7 +620,8 @@ __DEFINE_LXSYSCALL1(int, mkdir, const char*, path)
 {
     struct v_dnode *parent, *dir;
     struct hstr component = HSTR(valloc(VFS_NAME_MAXLEN), 0);
-    int errno = vfs_walk(NULL, path, &parent, &component, VFS_WALK_PARENT);
+    int errno =
+      vfs_walk(__current->cwd, path, &parent, &component, VFS_WALK_PARENT);
     if (errno) {
         goto done;
     }
@@ -611,7 +630,7 @@ __DEFINE_LXSYSCALL1(int, mkdir, const char*, path)
         errno = ENOTSUP;
     } else if (!parent->inode->ops.mkdir) {
         errno = ENOTSUP;
-    } else if (!(parent->inode->itype & VFS_INODE_TYPE_DIR)) {
+    } else if (!(parent->inode->itype & VFS_IFDIR)) {
         errno = ENOTDIR;
     } else {
         dir = vfs_d_alloc();
@@ -632,22 +651,18 @@ __DEFINE_LXSYSCALL3(int, read, int, fd, void*, buf, size_t, count)
 {
     int errno = 0;
     struct v_fd* fd_s;
-    if (!GET_FD(fd, fd_s)) {
-        errno = EBADF;
+    if ((errno = __vfs_getfd(fd, &fd_s))) {
         goto done;
     }
 
     struct v_file* file = fd_s->file;
-    if ((file->inode->itype & VFS_INODE_TYPE_DIR)) {
+    if ((file->inode->itype & VFS_IFDIR)) {
         errno = EISDIR;
         goto done;
     }
 
-    if ((fd_s->flags & FO_DIRECT)) {
-        errno = file->ops.read(file, buf, count, file->f_pos);
-    } else {
-        errno = pcache_read(file, buf, count);
-    }
+    __SYSCALL_INTERRUPTIBLE(
+      { errno = file->ops.read(file->inode, buf, count, file->f_pos); })
 
     if (errno > 0) {
         file->f_pos += errno;
@@ -662,22 +677,18 @@ __DEFINE_LXSYSCALL3(int, write, int, fd, void*, buf, size_t, count)
 {
     int errno = 0;
     struct v_fd* fd_s;
-    if (!GET_FD(fd, fd_s)) {
-        errno = EBADF;
+    if ((errno = __vfs_getfd(fd, &fd_s))) {
         goto done;
     }
 
     struct v_file* file = fd_s->file;
-    if ((file->inode->itype & VFS_INODE_TYPE_DIR)) {
+    if ((file->inode->itype & VFS_IFDIR)) {
         errno = EISDIR;
         goto done;
     }
 
-    if ((fd_s->flags & FO_DIRECT)) {
-        errno = file->ops.write(file, buf, count, file->f_pos);
-    } else {
-        errno = pcache_write(file, buf, count);
-    }
+    __SYSCALL_INTERRUPTIBLE(
+      { errno = file->ops.write(file->inode, buf, count, file->f_pos); })
 
     if (errno > 0) {
         file->f_pos += errno;
@@ -692,27 +703,28 @@ __DEFINE_LXSYSCALL3(int, lseek, int, fd, int, offset, int, options)
 {
     int errno = 0;
     struct v_fd* fd_s;
-    if (!GET_FD(fd, fd_s)) {
-        errno = EBADF;
-    } else {
-        struct v_file* file = fd_s->file;
-        size_t fpos = file->f_pos;
-        switch (options) {
-            case FSEEK_CUR:
-                fpos = (size_t)((int)file->f_pos + offset);
-                break;
-            case FSEEK_END:
-                fpos = (size_t)((int)file->inode->fsize + offset);
-                break;
-            case FSEEK_SET:
-                fpos = offset;
-                break;
-        }
-        if (!file->ops.seek || !(errno = file->ops.seek(file, fpos))) {
-            file->f_pos = fpos;
-        }
+    if ((errno = __vfs_getfd(fd, &fd_s))) {
+        goto done;
     }
 
+    struct v_file* file = fd_s->file;
+    size_t fpos = file->f_pos;
+    switch (options) {
+        case FSEEK_CUR:
+            fpos = (size_t)((int)file->f_pos + offset);
+            break;
+        case FSEEK_END:
+            fpos = (size_t)((int)file->inode->fsize + offset);
+            break;
+        case FSEEK_SET:
+            fpos = offset;
+            break;
+    }
+    if (!file->ops.seek || !(errno = file->ops.seek(file->inode, fpos))) {
+        file->f_pos = fpos;
+    }
+
+done:
     return DO_STATUS(errno);
 }
 
@@ -747,7 +759,7 @@ vfs_get_path(struct v_dnode* dnode, char* buf, size_t size, int depth)
 int
 vfs_readlink(struct v_dnode* dnode, char* buf, size_t size)
 {
-    char* link;
+    const char* link;
     if (dnode->inode->ops.read_symlink) {
         int errno = dnode->inode->ops.read_symlink(dnode->inode, &link);
         strncpy(buf, link, size);
@@ -760,17 +772,18 @@ __DEFINE_LXSYSCALL3(int, realpathat, int, fd, char*, buf, size_t, size)
 {
     int errno;
     struct v_fd* fd_s;
-    if (!GET_FD(fd, fd_s)) {
-        errno = EBADF;
-    } else {
-        struct v_dnode* dnode;
-        errno = vfs_get_path(fd_s->file->dnode, buf, size, 0);
+    if ((errno = __vfs_getfd(fd, &fd_s))) {
+        goto done;
     }
 
+    struct v_dnode* dnode;
+    errno = vfs_get_path(fd_s->file->dnode, buf, size, 0);
+
     if (errno >= 0) {
         return errno;
     }
 
+done:
     return DO_STATUS(errno);
 }
 
@@ -778,7 +791,8 @@ __DEFINE_LXSYSCALL3(int, readlink, const char*, path, char*, buf, size_t, size)
 {
     int errno;
     struct v_dnode* dnode;
-    if (!(errno = vfs_walk(NULL, path, &dnode, NULL, VFS_WALK_NOFOLLOW))) {
+    if (!(errno =
+            vfs_walk(__current->cwd, path, &dnode, NULL, VFS_WALK_NOFOLLOW))) {
         errno = vfs_readlink(dnode, buf, size);
     }
 
@@ -802,23 +816,21 @@ __DEFINE_LXSYSCALL4(int,
 {
     int errno;
     struct v_fd* fd_s;
-    if (!GET_FD(dirfd, fd_s)) {
-        errno = EBADF;
-    } else {
-        struct v_dnode* dnode;
-        if (!(errno = vfs_walk(fd_s->file->dnode,
-                               pathname,
-                               &dnode,
-                               NULL,
-                               VFS_WALK_NOFOLLOW))) {
-            errno = vfs_readlink(fd_s->file->dnode, buf, size);
-        }
+    if ((errno = __vfs_getfd(dirfd, &fd_s))) {
+        goto done;
+    }
+
+    struct v_dnode* dnode;
+    if (!(errno = vfs_walk(
+            fd_s->file->dnode, pathname, &dnode, NULL, VFS_WALK_NOFOLLOW))) {
+        errno = vfs_readlink(fd_s->file->dnode, buf, size);
     }
 
     if (errno >= 0) {
         return errno;
     }
 
+done:
     return DO_STATUS(errno);
 }
 
@@ -826,7 +838,7 @@ __DEFINE_LXSYSCALL1(int, rmdir, const char*, pathname)
 {
     int errno;
     struct v_dnode* dnode;
-    if ((errno = vfs_walk(NULL, pathname, &dnode, NULL, 0))) {
+    if ((errno = vfs_walk(__current->cwd, pathname, &dnode, NULL, 0))) {
         goto done;
     }
     if ((dnode->super_block->fs->types & FSTYPE_ROFS)) {
@@ -839,7 +851,7 @@ __DEFINE_LXSYSCALL1(int, rmdir, const char*, pathname)
         goto done;
     }
 
-    if ((dnode->inode->itype & VFS_INODE_TYPE_DIR)) {
+    if ((dnode->inode->itype & VFS_IFDIR)) {
         errno = dnode->inode->ops.rmdir(dnode->inode);
     } else {
         errno = ENOTDIR;
@@ -855,7 +867,7 @@ __vfs_do_unlink(struct v_inode* inode)
     int errno;
     if (inode->open_count) {
         errno = EBUSY;
-    } else if (!(inode->itype & VFS_INODE_TYPE_DIR)) {
+    } else if (!(inode->itype & VFS_IFDIR)) {
         // TODO handle symbolic link and type other than regular file
         errno = inode->ops.unlink(inode);
         if (!errno) {
@@ -872,7 +884,7 @@ __DEFINE_LXSYSCALL1(int, unlink, const char*, pathname)
 {
     int errno;
     struct v_dnode* dnode;
-    if ((errno = vfs_walk(NULL, pathname, &dnode, NULL, 0))) {
+    if ((errno = vfs_walk(__current->cwd, pathname, &dnode, NULL, 0))) {
         goto done;
     }
     if ((dnode->super_block->fs->types & FSTYPE_ROFS)) {
@@ -890,13 +902,13 @@ __DEFINE_LXSYSCALL2(int, unlinkat, int, fd, const char*, pathname)
 {
     int errno;
     struct v_fd* fd_s;
-    if (!GET_FD(fd, fd_s)) {
-        errno = EBADF;
-    } else {
-        struct v_dnode* dnode;
-        if (!(errno = vfs_walk(fd_s->file->dnode, pathname, &dnode, NULL, 0))) {
-            errno = __vfs_do_unlink(dnode->inode);
-        }
+    if ((errno = __vfs_getfd(fd, &fd_s))) {
+        goto done;
+    }
+
+    struct v_dnode* dnode;
+    if (!(errno = vfs_walk(fd_s->file->dnode, pathname, &dnode, NULL, 0))) {
+        errno = __vfs_do_unlink(dnode->inode);
     }
 
 done:
@@ -925,9 +937,7 @@ __DEFINE_LXSYSCALL1(int, fsync, int, fildes)
 {
     int errno;
     struct v_fd* fd_s;
-    if (!GET_FD(fildes, fd_s)) {
-        errno = EBADF;
-    } else {
+    if (!(errno = __vfs_getfd(fildes, &fd_s))) {
         errno = vfs_fsync(fd_s->file);
     }
 
@@ -935,7 +945,7 @@ __DEFINE_LXSYSCALL1(int, fsync, int, fildes)
 }
 
 int
-__vfs_dup_fd(struct v_fd* old, struct v_fd** new)
+vfs_dup_fd(struct v_fd* old, struct v_fd** new)
 {
     int errno = 0;
     struct v_fd* copied = cake_grab(fd_pile);
@@ -943,10 +953,13 @@ __vfs_dup_fd(struct v_fd* old, struct v_fd** new)
     memcpy(copied, old, sizeof(struct v_fd));
     old->file->ref_count++;
 
+    *new = copied;
+
     return errno;
 }
 
-__DEFINE_LXSYSCALL2(int, dup2, int, oldfd, int, newfd)
+int
+vfs_dup2(int oldfd, int newfd)
 {
     if (newfd == oldfd) {
         return newfd;
@@ -954,16 +967,21 @@ __DEFINE_LXSYSCALL2(int, dup2, int, oldfd, int, newfd)
 
     int errno;
     struct v_fd *oldfd_s, *newfd_s;
-    if (!GET_FD(oldfd, oldfd_s) || TEST_FD(newfd)) {
+    if ((errno = __vfs_getfd(oldfd, &oldfd_s))) {
+        goto done;
+    }
+
+    if (!TEST_FD(newfd)) {
         errno = EBADF;
         goto done;
     }
+
     newfd_s = __current->fdtable->fds[newfd];
-    if (newfd_s && (errno = vfs_close(newfd_s))) {
+    if (newfd_s && (errno = vfs_close(newfd_s->file))) {
         goto done;
     }
 
-    if (!(errno = __vfs_dup_fd(oldfd_s, &newfd_s))) {
+    if (!(errno = vfs_dup_fd(oldfd_s, &newfd_s))) {
         __current->fdtable->fds[newfd] = newfd_s;
         return newfd;
     }
@@ -972,18 +990,26 @@ done:
     return DO_STATUS(errno);
 }
 
+__DEFINE_LXSYSCALL2(int, dup2, int, oldfd, int, newfd)
+{
+    return vfs_dup2(oldfd, newfd);
+}
+
 __DEFINE_LXSYSCALL1(int, dup, int, oldfd)
 {
     int errno, newfd;
     struct v_fd *oldfd_s, *newfd_s;
-    if (!GET_FD(oldfd, oldfd_s)) {
-        errno = EBADF;
-    } else if (!(errno = vfs_alloc_fdslot(&newfd)) &&
-               !(errno = __vfs_dup_fd(oldfd_s, &newfd_s))) {
+    if ((errno = __vfs_getfd(oldfd, &oldfd_s))) {
+        goto done;
+    }
+
+    if (!(errno = vfs_alloc_fdslot(&newfd)) &&
+        !(errno = vfs_dup_fd(oldfd_s, &newfd_s))) {
         __current->fdtable->fds[newfd] = newfd_s;
         return newfd;
     }
 
+done:
     return DO_STATUS(errno);
 }
 
@@ -996,7 +1022,7 @@ __DEFINE_LXSYSCALL2(int,
 {
     int errno;
     struct v_dnode* dnode;
-    if ((errno = vfs_walk(NULL, pathname, &dnode, NULL, 0))) {
+    if ((errno = vfs_walk(__current->cwd, pathname, &dnode, NULL, 0))) {
         goto done;
     }
     if ((dnode->super_block->fs->types & FSTYPE_ROFS)) {
@@ -1012,4 +1038,85 @@ __DEFINE_LXSYSCALL2(int,
 
 done:
     return DO_STATUS(errno);
+}
+
+int
+__vfs_do_chdir(struct v_dnode* dnode)
+{
+    int errno = 0;
+    if (!(dnode->inode->itype & VFS_IFDIR)) {
+        errno = ENOTDIR;
+        goto done;
+    }
+
+    if (__current->cwd) {
+        __current->cwd->ref_count--;
+    }
+
+    dnode->ref_count++;
+    __current->cwd = dnode;
+
+done:
+    return errno;
+}
+
+__DEFINE_LXSYSCALL1(int, chdir, const char*, path)
+{
+    struct v_dnode* dnode;
+    int errno = 0;
+
+    if ((errno = vfs_walk(__current->cwd, path, &dnode, NULL, 0))) {
+        goto done;
+    }
+
+    errno = __vfs_do_chdir(dnode);
+
+done:
+    return DO_STATUS(errno);
+}
+
+__DEFINE_LXSYSCALL1(int, fchdir, int, fd)
+{
+    struct v_fd* fd_s;
+    int errno = 0;
+
+    if ((errno = __vfs_getfd(fd, &fd_s))) {
+        goto done;
+    }
+
+    errno = __vfs_do_chdir(fd_s->file->dnode);
+
+done:
+    return DO_STATUS(errno);
+}
+
+__DEFINE_LXSYSCALL2(char*, getcwd, char*, buf, size_t, size)
+{
+    int errno = 0;
+    char* ret_ptr = 0;
+    if (size < 2) {
+        errno = ERANGE;
+        goto done;
+    }
+
+    size_t len = 0;
+
+    if (!__current->cwd) {
+        *buf = PATH_DELIM;
+        len = 1;
+    } else {
+        len = vfs_get_path(__current->cwd, buf, size, 0);
+        if (len == size) {
+            errno = ERANGE;
+            goto done;
+        }
+    }
+
+    buf[len + 1] = '\0';
+
+    ret_ptr = buf;
+
+done:
+    __current->k_status = errno;
+    return ret_ptr;
 }
\ No newline at end of file