1
0
Fork 0
mirror of https://gitlab.com/sortix/sortix.git synced 2023-02-13 20:55:38 -05:00
sortix--sortix/sortix/fs/full.cpp
Jonas 'Sortie' Termansen caa1b7455c Add /dev/full.
2013-12-17 14:30:46 +01:00

103 lines
2.5 KiB
C++

/*******************************************************************************
Copyright(C) Jonas 'Sortie' Termansen 2013.
This file is part of Sortix.
Sortix 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.
Sortix 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
Sortix. If not, see <http://www.gnu.org/licenses/>.
fs/full.cpp
Bit bucket special device.
*******************************************************************************/
#include <sys/types.h>
#include <errno.h>
#include <stdint.h>
#include <string.h>
#include <sortix/stat.h>
#include <sortix/kernel/inode.h>
#include <sortix/kernel/ioctx.h>
#include "full.h"
namespace Sortix {
Full::Full(dev_t dev, ino_t ino, uid_t owner, gid_t group, mode_t mode)
{
inode_type = INODE_TYPE_STREAM;
if ( !dev )
dev = (dev_t) this;
if ( !ino )
ino = (ino_t) this;
this->type = S_IFCHR;
this->stat_uid = owner;
this->stat_gid = group;
this->stat_mode = (mode & S_SETABLE) | this->type;
this->stat_size = 0;
this->stat_blksize = 1;
this->dev = dev;
this->ino = ino;
}
Full::~Full()
{
}
int Full::truncate(ioctx_t* /*ctx*/, off_t /*length*/)
{
return 0;
}
off_t Full::lseek(ioctx_t* /*ctx*/, off_t offset, int /*whence*/)
{
return offset;
}
ssize_t Full::read(ioctx_t* ctx, uint8_t* buf, size_t count)
{
const size_t ZERO_MEM_SIZE = 128;
uint8_t zero_mem[ZERO_MEM_SIZE];
memset(zero_mem, 0, ZERO_MEM_SIZE);
size_t sofar = 0;
while ( sofar < count )
{
size_t left = count - sofar;
size_t amount = left < ZERO_MEM_SIZE ? left : ZERO_MEM_SIZE;
ctx->copy_to_dest(buf + sofar, zero_mem, amount);
sofar += amount;
}
return (ssize_t) sofar;
}
ssize_t Full::pread(ioctx_t* ctx, uint8_t* buf, size_t count, off_t /*off*/)
{
return read(ctx, buf, count);
}
ssize_t Full::write(ioctx_t* /*ctx*/, const uint8_t* /*buf*/, size_t count)
{
return count ? (errno = ENOSPC, -1) : 0;
}
ssize_t Full::pwrite(ioctx_t* /*ctx*/, const uint8_t* /*buf*/, size_t count,
off_t /*off*/)
{
return count ? (errno = ENOSPC, -1) : 0;
}
} // namespace Sortix