+ unlock_inode(inode);
+
+done:
+ return DO_STATUS(errno);
+}
+
+__DEFINE_LXSYSCALL3(int, read, int, fd, void*, buf, size_t, count)
+{
+ int errno = 0;
+ struct v_fd* fd_s;
+ if ((errno = __vfs_getfd(fd, &fd_s))) {
+ goto done;
+ }
+
+ struct v_file* file = fd_s->file;
+ if ((file->inode->itype & VFS_IFDIR)) {
+ errno = EISDIR;
+ goto done;
+ }
+
+ lock_inode(file->inode);
+
+ file->inode->atime = clock_unixtime();
+
+ __SYSCALL_INTERRUPTIBLE(
+ { errno = file->ops.read(file->inode, buf, count, file->f_pos); })
+
+ unlock_inode(file->inode);
+
+ if (errno > 0) {
+ file->f_pos += errno;
+ return errno;
+ }
+
+done:
+ return DO_STATUS(errno);
+}
+
+__DEFINE_LXSYSCALL3(int, write, int, fd, void*, buf, size_t, count)
+{
+ int errno = 0;
+ struct v_fd* fd_s;
+ if ((errno = __vfs_getfd(fd, &fd_s))) {
+ goto done;
+ }
+
+ struct v_file* file = fd_s->file;
+ if ((file->inode->itype & VFS_IFDIR)) {
+ errno = EISDIR;
+ goto done;
+ }
+
+ lock_inode(file->inode);
+
+ file->inode->mtime = clock_unixtime();
+
+ __SYSCALL_INTERRUPTIBLE(
+ { errno = file->ops.write(file->inode, buf, count, file->f_pos); })
+
+ unlock_inode(file->inode);
+
+ if (errno > 0) {
+ file->f_pos += errno;
+ return errno;
+ }
+
+done:
+ return DO_STATUS(errno);
+}
+
+__DEFINE_LXSYSCALL3(int, lseek, int, fd, int, offset, int, options)
+{
+ int errno = 0;
+ struct v_fd* fd_s;
+ if ((errno = __vfs_getfd(fd, &fd_s))) {
+ goto done;
+ }
+
+ struct v_file* file = fd_s->file;
+
+ lock_inode(file->inode);
+
+ 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;
+ }
+
+ unlock_inode(file->inode);
+
+done:
+ 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)
+{
+ const char* link;
+ struct v_inode* inode = dnode->inode;
+ if (inode->ops.read_symlink) {
+ lock_inode(inode);
+
+ int errno = inode->ops.read_symlink(inode, &link);
+ strncpy(buf, link, size);
+
+ unlock_inode(inode);
+ return errno;
+ }
+ return 0;
+}
+
+__DEFINE_LXSYSCALL3(int, realpathat, int, fd, char*, buf, size_t, size)
+{
+ int errno;
+ struct v_fd* fd_s;
+ 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);
+}
+
+__DEFINE_LXSYSCALL3(int, readlink, const char*, path, char*, buf, size_t, size)
+{
+ int errno;
+ struct v_dnode* dnode;
+ if (!(errno =
+ vfs_walk(__current->cwd, 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 ((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);
+}
+
+/*
+ NOTE
+ When we perform operation that could affect the layout of
+ directory (i.e., rename, mkdir, rmdir). We must lock the parent dir
+ whenever possible. This will blocking any ongoing path walking to reach
+ it hence avoid any partial state.
+*/
+
+__DEFINE_LXSYSCALL1(int, rmdir, const char*, pathname)
+{
+ int errno;
+ struct v_dnode* dnode;
+ if ((errno = vfs_walk(__current->cwd, pathname, &dnode, NULL, 0))) {
+ return DO_STATUS(errno);
+ }
+
+ lock_dnode(dnode);
+
+ if (dnode->parent)
+ lock_dnode(dnode->parent);
+
+ if ((dnode->super_block->fs->types & FSTYPE_ROFS)) {
+ errno = EROFS;
+ goto done;
+ }
+
+ if (dnode->ref_count || dnode->inode->open_count) {
+ errno = EBUSY;
+ goto done;
+ }
+
+ if (!llist_empty(&dnode->children)) {
+ errno = ENOTEMPTY;
+ goto done;
+ }
+
+ lock_inode(dnode->inode);
+
+ if ((dnode->inode->itype & VFS_IFDIR)) {
+ errno = dnode->inode->ops.rmdir(dnode->inode);
+ // FIXME remove the dnode from cache & parent.
+ } else {
+ errno = ENOTDIR;
+ }
+
+ unlock_inode(dnode->inode);
+
+done:
+ unlock_dnode(dnode);
+ if (dnode->parent)
+ unlock_dnode(dnode->parent);
+ return DO_STATUS(errno);
git://scm.lunaixsky.com / lunaix-os.git / blobdiff