1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/libfsserver/lib/files/host_file_accessor.cc Thu Apr 15 23:15:17 2021 +0200
1.3 @@ -0,0 +1,85 @@
1.4 +/*
1.5 + * A file accessor employing a "host" file provided via the C library.
1.6 + *
1.7 + * Copyright (C) 2021 Paul Boddie <paul@boddie.org.uk>
1.8 + *
1.9 + * This program is free software; you can redistribute it and/or
1.10 + * modify it under the terms of the GNU General Public License as
1.11 + * published by the Free Software Foundation; either version 2 of
1.12 + * the License, or (at your option) any later version.
1.13 + *
1.14 + * This program is distributed in the hope that it will be useful,
1.15 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
1.16 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
1.17 + * GNU General Public License for more details.
1.18 + *
1.19 + * You should have received a copy of the GNU General Public License
1.20 + * along with this program; if not, write to the Free Software
1.21 + * Foundation, Inc., 51 Franklin Street, Fifth Floor,
1.22 + * Boston, MA 02110-1301, USA
1.23 + */
1.24 +
1.25 +#include <stdio.h>
1.26 +#include <string.h>
1.27 +#include <sys/types.h>
1.28 +#include <sys/stat.h>
1.29 +
1.30 +#include "host_file_accessor.h"
1.31 +
1.32 +HostFileAccessor::HostFileAccessor(const char *path, fileid_t fileid)
1.33 +: Accessor(fileid), _path(path)
1.34 +{
1.35 + /* Initialise the size of the file. */
1.36 +
1.37 + struct stat buf;
1.38 +
1.39 + if (!stat(_path, &buf))
1.40 + _size = buf.st_size;
1.41 + else
1.42 + _size = 0;
1.43 +}
1.44 +
1.45 +/* Perform any closing operation on the file. */
1.46 +
1.47 +void HostFileAccessor::close()
1.48 +{
1.49 + fclose(_fp);
1.50 +}
1.51 +
1.52 +/* Perform any opening operation on the file. */
1.53 +
1.54 +void HostFileAccessor::open()
1.55 +{
1.56 + _fp = fopen(_path, "r");
1.57 +}
1.58 +
1.59 +/* Data transfer helper methods. */
1.60 +
1.61 +void HostFileAccessor::fill_populated(Flexpage *flexpage)
1.62 +{
1.63 + offset_t filepos = flexpage->base_offset;
1.64 + offset_t addr = flexpage->base_addr;
1.65 +
1.66 + /* Seek to the offset in the file. */
1.67 +
1.68 + fseek(_fp, filepos, SEEK_SET);
1.69 +
1.70 + /* Tag the region with file state. */
1.71 +
1.72 + flexpage->region->fill(fileid, filepos);
1.73 +
1.74 + /* Fill the region with file content. */
1.75 +
1.76 + size_t nread = fread((void *) addr, sizeof(char), flexpage->size, _fp);
1.77 +
1.78 + /* Pad the flexpage with zero. */
1.79 +
1.80 + memset((void *) (addr + nread), 0, flexpage->size - nread);
1.81 +}
1.82 +
1.83 +void HostFileAccessor::flush_populated(Flexpage *flexpage)
1.84 +{
1.85 + flexpage->region->flush();
1.86 +}
1.87 +
1.88 +// vim: tabstop=4 expandtab shiftwidth=4