profuse/RawDevice.cpp

188 lines
3.6 KiB
C++

#include <sys/ioctl.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/uio.h>
#include <unistd.h>
#include <cerrno>
#ifdef __APPLE__
#include <sys/disk.h>
#endif
#ifdef __LINUX__
#include <sys/mount.h>
#endif
#ifdef __SUN__
#include <sys/dkio.h>
#endif
#include "RawDevice.h"
#include "auto.h"
#include "Exception.h"
using namespace ProFUSE;
#ifdef __SUN__
void RawDevice::devSize(int fd)
{
#undef __METHOD__
#define __METHOD__ "RawDevice::devSize"
struct dk_minfo minfo;
if (::ioctl(fd, DKIOCGMEDIAINFO, &minfo) < 0)
throw Exception(__METHOD__ ": Unable to determine device size.", errno);
_size = minfo.dki_lbsize * minfo.dki_capacity;
_blockSize = 512; // not really, but whatever.
_blocks = _size / 512;
}
#endif
#ifdef __APPLE__
void RawDevice::devSize(int fd)
{
#undef __METHOD__
#define __METHOD__ "RawDevice::devSize"
uint32_t blockSize; // 32 bit
uint64_t blockCount; // 64 bit
if (::ioctl(fd, DKIOCGETBLOCKSIZE, &blockSize) < 0)
throw Exception(__METHOD__ ": Unable to determine block size.", errno);
if (::ioctl(fd, DKIOCGETBLOCKCOUNT, &blockCount) < 0)
throw Exception(__METHOD__ ": Unable to determine block count.", errno);
_blockSize = blockSize;
_size = _blockSize * blockCount;
_blocks = _size / 512;
}
#endif
#ifdef __LINUX__
void RawDevice::devSize(int fd)
{
#undef __METHOD__
#define __METHOD__ "RawDevice::devSize"
int blocks;
if (::ioctl(fd, BLKGETSIZE, &blocks) < 0)
throw Exception(__METHOD__ ": Unable to determine device size.", errno);
_size = 512 * blocks;
_blockSize = 512; //
_blocks = blocks;
}
#endif
// TODO -- FreeBSD/NetBSD/OpenBSD
RawDevice::RawDevice(const char *name, bool readOnly)
{
#undef __METHOD__
#define __METHOD__ "RawDevice::RawDevice"
// open read-only, verify if device is readable, and then try to upgrade to read/write?
auto_fd fd;
if (!readOnly) fd.reset(::open(name, O_RDWR));
if (fd < 0)
{
readOnly = false;
fd.reset(::open(name, O_RDONLY));
}
if (fd < 0)
throw Exception(__METHOD__ ": Unable to open device.", errno);
_fd = -1;
_readOnly = readOnly;
_size = 0;
_blocks = 0;
_blockSize = 0;
devSize(fd);
_fd = fd.release();
}
RawDevice::~RawDevice()
{
if (_fd >= 0) ::close(_fd);
}
void RawDevice::read(unsigned block, void *bp)
{
#undef __METHOD__
#define __METHOD__ "RawDevice::read"
if (block >= _blocks) throw Exception(__METHOD__ ": Invalid block number.");
if (bp == 0) throw Exception(__METHOD__ ": Invalid address.");
// sun -- use pread
// apple - read full native block(s) ?
size_t ok = ::pread(_fd, bp, 512, block * 512);
// TODO -- EINTR?
if (ok != 512)
throw Exception(__METHOD__ ": Error reading block.",
ok < 0 ? errno : 0);
}
void RawDevice::write(unsigned block, const void *bp)
{
#undef __METHOD__
#define __METHOD__ "RawDevice::write"
if (block > _blocks) throw Exception(__METHOD__ ": Invalid block number.");
if (_readOnly)
throw Exception(__METHOD__ ": File is readonly.");
size_t ok = ::pwrite(_fd, bp, 512, block * 512);
if (ok != 512)
throw Exception(__METHOD__ ": Error writing block.",
ok < 0 ? errno : 0);
}
bool RawDevice::readOnly()
{
return _readOnly;
}
void RawDevice::sync()
{
#undef __METHOD__
#define __METHOD__ "RawDevice::sync"
if (_readOnly) return;
if (::fsync(_fd) < 0)
throw Exception(__METHOD__ ": fsync error.", errno);
}