diff options
Diffstat (limited to 'source3/smbd/fileio.c')
-rw-r--r-- | source3/smbd/fileio.c | 321 |
1 files changed, 321 insertions, 0 deletions
diff --git a/source3/smbd/fileio.c b/source3/smbd/fileio.c new file mode 100644 index 0000000..e5de827 --- /dev/null +++ b/source3/smbd/fileio.c @@ -0,0 +1,321 @@ +/* + Unix SMB/Netbios implementation. + Version 1.9. + read/write to a files_struct + Copyright (C) Andrew Tridgell 1992-1998 + Copyright (C) Jeremy Allison 2000-2002. - write cache. + + 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 "printing.h" +#include "smbd/smbd.h" +#include "smbd/globals.h" +#include "smbprofile.h" + +/**************************************************************************** + Read from a file. +****************************************************************************/ + +ssize_t read_file(files_struct *fsp,char *data,off_t pos,size_t n) +{ + off_t new_pos; + ssize_t ret = 0; + bool ok; + + /* you can't read from print files */ + if (fsp->print_file) { + errno = EBADF; + return -1; + } + + ok = vfs_valid_pread_range(pos, n); + if (!ok) { + errno = EINVAL; + return -1; + } + + fh_set_pos(fsp->fh, pos); + + if (n > 0) { + ret = SMB_VFS_PREAD(fsp,data,n,pos); + + if (ret == -1) { + return -1; + } + } + + DEBUG(10,("read_file (%s): pos = %.0f, size = %lu, returned %lu\n", + fsp_str_dbg(fsp), (double)pos, (unsigned long)n, (long)ret)); + + new_pos = fh_get_pos(fsp->fh) + ret; + fh_set_pos(fsp->fh, new_pos); + fh_set_position_information(fsp->fh, new_pos); + + return(ret); +} + +/**************************************************************************** + *Really* write to a file. +****************************************************************************/ + +static ssize_t real_write_file(struct smb_request *req, + files_struct *fsp, + const char *data, + off_t pos, + size_t n) +{ + ssize_t ret; + bool ok; + + ok = vfs_valid_pwrite_range(pos, n); + if (!ok) { + errno = EINVAL; + return -1; + } + + if (n == 0) { + return 0; + } + + fh_set_pos(fsp->fh, pos); + if (pos && + lp_strict_allocate(SNUM(fsp->conn)) && + !fsp->fsp_flags.is_sparse) + { + if (vfs_fill_sparse(fsp, pos) == -1) { + return -1; + } + } + ret = vfs_pwrite_data(req, fsp, data, n, pos); + + DEBUG(10,("real_write_file (%s): pos = %.0f, size = %lu, returned %ld\n", + fsp_str_dbg(fsp), (double)pos, (unsigned long)n, (long)ret)); + + if (ret != -1) { + off_t new_pos = fh_get_pos(fsp->fh) + ret; + fh_set_pos(fsp->fh, new_pos); + +/* Yes - this is correct - writes don't update this. JRA. */ +/* Found by Samba4 tests. */ +#if 0 + fsp->position_information = fsp->pos; +#endif + } + + return ret; +} + +void fsp_flush_write_time_update(struct files_struct *fsp) +{ + /* + * Note this won't expect any impersonation! + * So don't call any SMB_VFS operations here! + */ + + DEBUG(5, ("Update write time on %s\n", fsp_str_dbg(fsp))); + + trigger_write_time_update_immediate(fsp); +} + +static void update_write_time_handler(struct tevent_context *ctx, + struct tevent_timer *te, + struct timeval now, + void *private_data) +{ + files_struct *fsp = (files_struct *)private_data; + fsp_flush_write_time_update(fsp); +} + +/********************************************************* + Schedule a write time update for WRITE_TIME_UPDATE_USEC_DELAY + in the future. +*********************************************************/ + +void trigger_write_time_update(struct files_struct *fsp) +{ + int delay; + + if (fsp->posix_flags & FSP_POSIX_FLAGS_OPEN) { + /* Don't use delayed writes on POSIX files. */ + return; + } + + if (fsp->fsp_flags.write_time_forced) { + /* No point - "sticky" write times + * in effect. + */ + return; + } + + /* We need to remember someone did a write + * and update to current time on close. */ + + fsp->fsp_flags.update_write_time_on_close = true; + + if (fsp->fsp_flags.update_write_time_triggered) { + /* + * We only update the write time after 2 seconds + * on the first normal write. After that + * no other writes affect this until close. + */ + return; + } + fsp->fsp_flags.update_write_time_triggered = true; + + delay = lp_parm_int(SNUM(fsp->conn), + "smbd", "writetimeupdatedelay", + WRITE_TIME_UPDATE_USEC_DELAY); + + DEBUG(5, ("Update write time %d usec later on %s\n", + delay, fsp_str_dbg(fsp))); + + /* trigger the update 2 seconds later */ + fsp->update_write_time_event = + tevent_add_timer(fsp->conn->sconn->ev_ctx, NULL, + timeval_current_ofs_usec(delay), + update_write_time_handler, fsp); +} + +void trigger_write_time_update_immediate(struct files_struct *fsp) +{ + struct smb_file_time ft; + + init_smb_file_time(&ft); + + if (fsp->posix_flags & FSP_POSIX_FLAGS_OPEN) { + /* Don't use delayed writes on POSIX files. */ + return; + } + + if (fsp->fsp_flags.write_time_forced) { + /* + * No point - "sticky" write times + * in effect. + */ + return; + } + + TALLOC_FREE(fsp->update_write_time_event); + DEBUG(5, ("Update write time immediate on %s\n", + fsp_str_dbg(fsp))); + + /* After an immediate update, reset the trigger. */ + fsp->fsp_flags.update_write_time_triggered = true; + fsp->fsp_flags.update_write_time_on_close = false; + + ft.mtime = timespec_current(); + + /* Update the time in the open file db. */ + (void)set_write_time(fsp->file_id, ft.mtime); + + /* Now set on disk - takes care of notify. */ + (void)smb_set_file_time(fsp->conn, fsp, fsp->fsp_name, &ft, false); +} + +void mark_file_modified(files_struct *fsp) +{ + int dosmode; + + trigger_write_time_update(fsp); + + if (fsp->fsp_flags.modified) { + return; + } + + fsp->fsp_flags.modified = true; + + if (fsp->posix_flags & FSP_POSIX_FLAGS_OPEN) { + return; + } + if (!(lp_store_dos_attributes(SNUM(fsp->conn)) || + MAP_ARCHIVE(fsp->conn))) { + return; + } + + dosmode = fdos_mode(fsp); + if (IS_DOS_ARCHIVE(dosmode)) { + return; + } + file_set_dosmode(fsp->conn, fsp->fsp_name, + dosmode | FILE_ATTRIBUTE_ARCHIVE, NULL, false); +} + +/**************************************************************************** + Write to a file. +****************************************************************************/ + +ssize_t write_file(struct smb_request *req, + files_struct *fsp, + const char *data, + off_t pos, + size_t n) +{ + ssize_t total_written = 0; + + if (fsp->print_file) { + uint32_t t; + int ret; + + ret = print_spool_write(fsp, data, n, pos, &t); + if (ret) { + errno = ret; + return -1; + } + return t; + } + + if (!fsp->fsp_flags.can_write) { + errno = EPERM; + return -1; + } + + mark_file_modified(fsp); + + /* + * If this file is level II oplocked then we need + * to grab the shared memory lock and inform all + * other files with a level II lock that they need + * to flush their read caches. We keep the lock over + * the shared memory area whilst doing this. + */ + + /* This should actually be improved to span the write. */ + contend_level2_oplocks_begin(fsp, LEVEL2_CONTEND_WRITE); + contend_level2_oplocks_end(fsp, LEVEL2_CONTEND_WRITE); + + total_written = real_write_file(req, fsp, data, pos, n); + return total_written; +} + +/******************************************************************* +sync a file +********************************************************************/ + +NTSTATUS sync_file(connection_struct *conn, files_struct *fsp, bool write_through) +{ + if (fsp_get_io_fd(fsp) == -1) + return NT_STATUS_INVALID_HANDLE; + + if (lp_strict_sync(SNUM(conn)) && + (lp_sync_always(SNUM(conn)) || write_through)) { + int ret; + ret = smb_vfs_fsync_sync(fsp); + if (ret == -1) { + return map_nt_error_from_unix(errno); + } + } + return NT_STATUS_OK; +} |