struct hstr vfs_ddot = HSTR("..", 2);
struct hstr vfs_dot = HSTR(".", 1);
+struct hstr vfs_empty = HSTR("", 0);
struct v_dnode*
vfs_d_alloc();
struct v_dnode*
vfs_dcache_lookup(struct v_dnode* parent, struct hstr* str)
{
- if (!str->len)
+ if (!str->len || HSTR_EQ(str, &vfs_dot))
return parent;
+ if (HSTR_EQ(str, &vfs_ddot)) {
+ return parent->parent ? parent->parent : parent;
+ }
+
struct hbucket* slot = __dcache_get_bucket(parent, str->hash);
struct v_dnode *pos, *n;
}
int
-vfs_walk(struct v_dnode* start,
- const char* path,
- struct v_dnode** dentry,
- struct hstr* component,
- int walk_options)
+__vfs_walk(struct v_dnode* start,
+ const char* path,
+ struct v_dnode** dentry,
+ struct hstr* component,
+ int walk_options)
{
int errno = 0;
int i = 0, j = 0;
if (!dnode) {
dnode = vfs_d_alloc();
- dnode->name = HSTR(valloc(VFS_NAME_MAXLEN), j);
- dnode->name.hash = name.hash;
+ dnode->name = HHSTR(valloc(VFS_NAME_MAXLEN), j, name.hash);
strcpy(dnode->name.value, name_content);
return errno;
}
+#define VFS_MAX_SYMLINK 16
+
+int
+vfs_walk(struct v_dnode* start,
+ const char* path,
+ struct v_dnode** dentry,
+ struct hstr* component,
+ int options)
+{
+ struct v_dnode* interim;
+ char* pathname = path;
+ int errno = __vfs_walk(start, path, &interim, component, options);
+ int counter = 0;
+
+ while (!errno) {
+ if (counter >= VFS_MAX_SYMLINK) {
+ errno = ELOOP;
+ continue;
+ }
+ if ((interim->inode->itype & VFS_INODE_TYPE_SYMLINK) &&
+ !(options & VFS_WALK_NOFOLLOW) &&
+ interim->inode->ops.read_symlink) {
+ errno = interim->inode->ops.read_symlink(interim->inode, &pathname);
+ if (errno) {
+ break;
+ }
+ } else {
+ break;
+ }
+ errno =
+ __vfs_walk_internal(start, pathname, &interim, component, options);
+ counter++;
+ }
+
+ *dentry = errno ? 0 : interim;
+
+ return errno;
+}
+
int
vfs_mount(const char* target, const char* fs_name, bdev_t device)
{
struct v_file* vfile = cake_grab(file_pile);
memset(vfile, 0, sizeof(*vfile));
+ vfile->dnode = dnode;
+ vfile->inode = dnode->inode;
+ dnode->inode->open_count++;
+
int errno = dnode->inode->ops.open(dnode->inode, vfile);
if (errno) {
cake_release(file_pile, vfile);
return errno;
}
+int
+vfs_link(struct v_dnode* to_link, struct v_dnode* name)
+{
+ int errno;
+ if (to_link->super_block->root != name->super_block->root) {
+ errno = EXDEV;
+ } else if (!to_link->inode->ops.link) {
+ errno = ENOTSUP;
+ } else if (!(errno = to_link->inode->ops.link(to_link->inode, name))) {
+ name->inode = to_link->inode;
+ to_link->inode->link_count++;
+ }
+
+ return errno;
+}
+
int
vfs_close(struct v_file* file)
{
int errno = file->ops.close(file);
if (!errno) {
+ if (file->inode->open_count) {
+ file->inode->open_count--;
+ }
cake_release(file_pile, file);
}
return errno;
struct v_dnode* dnode = cake_grab(dnode_pile);
memset(dnode, 0, sizeof(*dnode));
llist_init_head(&dnode->children);
+ dnode->name = vfs_empty;
return dnode;
}
cake_release(inode_pile, inode);
}
+/* ---- System call definition and support ---- */
+
+#define FLOCATE_CREATE_EMPTY 1
+
+#define DO_STATUS(errno) SYSCALL_ESTATUS(__current->k_status = errno)
+
int
-__vfs_do_open(struct v_file** file_out, const char* path, int options)
+__vfs_try_locate_file(const char* path,
+ struct v_dnode** fdir,
+ struct v_dnode** file,
+ int options)
{
char name_str[VFS_NAME_MAXLEN];
struct hstr name = HSTR(name_str, 0);
- struct v_dnode *dentry, *file;
int errno;
- if ((errno = vfs_walk(NULL, path, &dentry, &name, VFS_WALK_PARENT))) {
- return ENOENT;
+ if (!(errno = vfs_walk(NULL, path, fdir, &name, VFS_WALK_PARENT))) {
+ errno = vfs_walk(*fdir, name.value, file, NULL, 0);
+ if (errno == ENOENT && (options & FLOCATE_CREATE_EMPTY)) {
+ struct v_dnode* file_new;
+ file_new = vfs_d_alloc();
+ file_new->name =
+ HHSTR(valloc(VFS_NAME_MAXLEN), name.len, name.hash);
+ strcpy(file_new->name.value, name_str);
+ *file = file_new;
+
+ llist_append(&(*fdir)->children, &file_new->siblings);
+ }
}
- vfs_walk(dentry, name.value, &file, NULL, 0);
+ return errno;
+}
+int
+__vfs_do_open(struct v_file** file_out, const char* path, int options)
+{
+ int errno;
+ struct v_dnode *dentry, *file;
struct v_file* opened_file = 0;
- if (!file) {
- if ((options & FO_CREATE)) {
- errno = dentry->inode->ops.create(dentry->inode, opened_file);
- } else {
- errno = ENOENT;
- }
- } else {
+
+ errno = __vfs_try_locate_file(path, &dentry, &file, 0);
+
+ if (errno != ENOENT && (options & FO_CREATE)) {
+ errno = dentry->inode->ops.create(dentry->inode, opened_file);
+ } else if (!errno) {
errno = vfs_open(file, &opened_file);
}
struct v_file* opened_file;
int errno = __vfs_do_open(&opened_file, path, options), fd;
- __current->k_status = errno;
-
if (!errno && !(errno = vfs_alloc_fdslot(&fd))) {
struct v_fd* fd_s = vzalloc(sizeof(*fd_s));
fd_s->file = opened_file;
return fd;
}
- return SYSCALL_ESTATUS(errno);
+ return DO_STATUS(errno);
}
-
-#define GET_FD(fd, fd_s) \
- (fd >= 0 && fd < VFS_MAX_FD && (fd_s = __current->fdtable->fds[fd]))
+#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)
{
__current->fdtable->fds[fd] = 0;
}
- __current->k_status = errno;
-
- return SYSCALL_ESTATUS(errno);
+ return DO_STATUS(errno);
}
void
.index = dent->d_offset,
.read_complete_callback =
__vfs_readdir_callback };
- if (!(errno = fd_s->file->ops.readdir(fd_s->file, &dctx))) {
- dent->d_offset++;
+ if (dent->d_offset == 0) {
+ __vfs_readdir_callback(&dctx, vfs_dot.value, vfs_dot.len, 0);
+ } else if (dent->d_offset == 1) {
+ __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))) {
+ goto done;
+ }
}
+ errno = 0;
+ dent->d_offset++;
}
- __current->k_status = errno;
- return SYSCALL_ESTATUS(errno);
+done:
+ return DO_STATUS(errno);
}
__DEFINE_LXSYSCALL1(int, mkdir, const char*, path)
}
done:
- __current->k_status = errno;
- return SYSCALL_ESTATUS(errno);
+ return DO_STATUS(errno);
}
__DEFINE_LXSYSCALL3(int, read, int, fd, void*, buf, size_t, count)
}
}
- __current->k_status = errno;
- return SYSCALL_ESTATUS(errno);
+ return DO_STATUS(errno);
}
__DEFINE_LXSYSCALL3(int, write, int, fd, void*, buf, size_t, count)
}
}
- __current->k_status = errno;
- return SYSCALL_ESTATUS(errno);
+ return DO_STATUS(errno);
}
__DEFINE_LXSYSCALL3(int, lseek, int, fd, int, offset, int, options)
fd_s->pos = fpos;
}
- __current->k_status = errno;
- return SYSCALL_ESTATUS(errno);
+ return DO_STATUS(errno);
+}
+
+int
+vfs_get_path(struct v_dnode* dnode, char* buf, size_t size, int depth)
+{
+ if (!dnode) {
+ return 0;
+ }
+
+ if (depth > 64) {
+ return ELOOP;
+ }
+
+ size_t len = vfs_get_path(dnode->parent, buf, size, depth + 1);
+
+ if (len >= size) {
+ return len;
+ }
+
+ size_t cpy_size = MIN(dnode->name.len, size - len);
+ strncpy(buf + len, dnode->name.value, cpy_size);
+ len += cpy_size;
+
+ if (len < size) {
+ buf[len++] = PATH_DELIM;
+ }
+
+ return len;
+}
+
+int
+vfs_readlink(struct v_dnode* dnode, char* buf, size_t size)
+{
+ char* link;
+ if (dnode->inode->ops.read_symlink) {
+ int errno = dnode->inode->ops.read_symlink(dnode->inode, &link);
+ strncpy(buf, link, size);
+ return errno;
+ }
+ return 0;
+}
+
+__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 >= 0) {
+ return errno;
+ }
+
+ return DO_STATUS(errno);
+}
+
+__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))) {
+ errno = vfs_readlink(dnode, buf, size);
+ }
+
+ if (errno >= 0) {
+ return errno;
+ }
+
+ return DO_STATUS(errno);
+}
+
+__DEFINE_LXSYSCALL4(int,
+ readlinkat,
+ int,
+ dirfd,
+ const char*,
+ pathname,
+ char*,
+ buf,
+ size_t,
+ size)
+{
+ 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 >= 0) {
+ return errno;
+ }
+
+ return DO_STATUS(errno);
+}
+
+__DEFINE_LXSYSCALL1(int, rmdir, const char*, pathname)
+{
+ int errno;
+ struct v_dnode* dnode;
+ if ((errno = vfs_walk(NULL, pathname, &dnode, NULL, 0))) {
+ goto done;
+ }
+ if ((dnode->super_block->fs->types & FSTYPE_ROFS)) {
+ errno = EROFS;
+ goto done;
+ }
+
+ if (dnode->inode->open_count) {
+ errno = EBUSY;
+ goto done;
+ }
+
+ if ((dnode->inode->itype & VFS_INODE_TYPE_DIR)) {
+ errno = dnode->inode->ops.rmdir(dnode->inode);
+ } else {
+ errno = ENOTDIR;
+ }
+
+done:
+ return DO_STATUS(errno);
+}
+
+int
+__vfs_do_unlink(struct v_inode* inode)
+{
+ int errno;
+ if (inode->open_count) {
+ errno = EBUSY;
+ } else if (!(inode->itype & VFS_INODE_TYPE_DIR)) {
+ // TODO handle symbolic link and type other than regular file
+ errno = inode->ops.unlink(inode);
+ if (!errno) {
+ inode->link_count--;
+ }
+ } else {
+ errno = EISDIR;
+ }
+
+ return errno;
+}
+
+__DEFINE_LXSYSCALL1(int, unlink, const char*, pathname)
+{
+ int errno;
+ struct v_dnode* dnode;
+ if ((errno = vfs_walk(NULL, pathname, &dnode, NULL, 0))) {
+ goto done;
+ }
+ if ((dnode->super_block->fs->types & FSTYPE_ROFS)) {
+ errno = EROFS;
+ goto done;
+ }
+
+ errno = __vfs_do_unlink(dnode->inode);
+
+done:
+ return DO_STATUS(errno);
+}
+
+__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);
+ }
+ }
+
+done:
+ return DO_STATUS(errno);
+}
+
+__DEFINE_LXSYSCALL2(int, link, const char*, oldpath, const char*, newpath)
+{
+ int errno;
+ struct v_dnode *dentry, *to_link, *name_dentry, *name_file;
+
+ errno = __vfs_try_locate_file(oldpath, &dentry, &to_link, 0);
+ if (!errno) {
+ errno = __vfs_try_locate_file(
+ newpath, &name_dentry, &name_file, FLOCATE_CREATE_EMPTY);
+ if (!errno) {
+ errno = EEXIST;
+ } else if (name_file) {
+ errno = vfs_link(to_link, name_file);
+ }
+ }
+ return DO_STATUS(errno);
+}
+
+__DEFINE_LXSYSCALL1(int, fsync, int, fildes)
+{
+ int errno;
+ struct v_fd* fd_s;
+ if (!GET_FD(fildes, fd_s)) {
+ errno = EBADF;
+ } else {
+ errno = vfs_fsync(fd_s->file);
+ }
+
+ return DO_STATUS(errno);
+}
+
+int
+__vfs_dup_fd(struct v_fd* old, struct v_fd** new)
+{
+ int errno = 0;
+ struct v_file* newopened;
+ if (!(errno = vfs_open(old->file->dnode, &newopened))) {
+ *new = cake_grab(fd_pile);
+ **new = (struct v_fd){ .file = newopened,
+ .pos = old->pos,
+ .flags = old->flags };
+ }
+
+ return errno;
+}
+
+__DEFINE_LXSYSCALL2(int, dup2, int, oldfd, int, newfd)
+{
+ if (newfd == oldfd) {
+ return newfd;
+ }
+
+ int errno;
+ struct v_fd *oldfd_s, *newfd_s;
+ if (!GET_FD(oldfd, oldfd_s) || TEST_FD(newfd)) {
+ errno = EBADF;
+ goto done;
+ }
+ newfd_s = __current->fdtable->fds[newfd];
+ if (newfd_s && (errno = vfs_close(newfd_s))) {
+ goto done;
+ }
+
+ if (!(errno = __vfs_dup_fd(oldfd_s, &newfd_s))) {
+ __current->fdtable->fds[newfd] = newfd_s;
+ return newfd;
+ }
+
+done:
+ return DO_STATUS(errno);
+}
+
+__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))) {
+ __current->fdtable->fds[newfd] = newfd_s;
+ return newfd;
+ }
+
+ return DO_STATUS(errno);
+}
+
+__DEFINE_LXSYSCALL2(int,
+ symlink,
+ const char*,
+ pathname,
+ const char*,
+ link_target)
+{
+ int errno;
+ struct v_dnode* dnode;
+ if ((errno = vfs_walk(NULL, pathname, &dnode, NULL, 0))) {
+ goto done;
+ }
+ if ((dnode->super_block->fs->types & FSTYPE_ROFS)) {
+ errno = EROFS;
+ goto done;
+ }
+ if (!dnode->inode->ops.symlink) {
+ errno = ENOTSUP;
+ goto done;
+ }
+
+ errno = dnode->inode->ops.symlink(dnode->inode, link_target);
+
+done:
+ return DO_STATUS(errno);
}
\ No newline at end of file
git://scm.lunaixsky.com / lunaix-os.git / blobdiff