/* Unix SMB/CIFS implementation. POSIX NTVFS backend - read Copyright (C) Andrew Tridgell 2004 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see <http://www.gnu.org/licenses/>. */ #include "includes.h" #include "vfs_posix.h" #include "lib/events/events.h" /* read from a file */ NTSTATUS pvfs_read(struct ntvfs_module_context *ntvfs, struct ntvfs_request *req, union smb_read *rd) { struct pvfs_state *pvfs = ntvfs->private_data; ssize_t ret; struct pvfs_file *f; NTSTATUS status; uint32_t maxcnt; uint32_t mask; if (rd->generic.level != RAW_READ_READX) { return ntvfs_map_read(ntvfs, req, rd); } f = pvfs_find_fd(pvfs, req, rd->readx.in.file.ntvfs); if (!f) { return NT_STATUS_INVALID_HANDLE; } if (f->handle->fd == -1) { return NT_STATUS_FILE_IS_A_DIRECTORY; } mask = SEC_FILE_READ_DATA; if (rd->readx.in.read_for_execute) { mask |= SEC_FILE_EXECUTE; } if (!(f->access_mask & mask)) { return NT_STATUS_ACCESS_DENIED; } maxcnt = rd->readx.in.maxcnt; if (maxcnt > UINT16_MAX && req->ctx->protocol < PROTOCOL_SMB2) { maxcnt = 0; } status = pvfs_check_lock(pvfs, f, req->smbpid, rd->readx.in.offset, maxcnt, READ_LOCK); if (!NT_STATUS_IS_OK(status)) { return status; } if (f->handle->name->stream_name) { ret = pvfs_stream_read(pvfs, f->handle, rd->readx.out.data, maxcnt, rd->readx.in.offset); } else { #if HAVE_LINUX_AIO /* possibly try an aio read */ if ((req->async_states->state & NTVFS_ASYNC_STATE_MAY_ASYNC) && (pvfs->flags & PVFS_FLAG_LINUX_AIO)) { status = pvfs_aio_pread(req, rd, f, maxcnt); if (NT_STATUS_IS_OK(status)) { return NT_STATUS_OK; } } #endif ret = pread(f->handle->fd, rd->readx.out.data, maxcnt, rd->readx.in.offset); } if (ret == -1) { return pvfs_map_errno(pvfs, errno); } /* only SMB2 honors mincnt */ if (req->ctx->protocol == PROTOCOL_SMB2) { if (rd->readx.in.mincnt > ret || (ret == 0 && maxcnt > 0)) { return NT_STATUS_END_OF_FILE; } } f->handle->position = f->handle->seek_offset = rd->readx.in.offset + ret; rd->readx.out.nread = ret; rd->readx.out.remaining = 0xFFFF; rd->readx.out.compaction_mode = 0; return NT_STATUS_OK; }