newlib-cygwin/winsup/cygwin/fhandler_raw.cc

570 lines
11 KiB
C++

/* fhandler_raw.cc. See fhandler.h for a description of the fhandler classes.
Copyright 1999, 2000, 2001, 2002, 2003, 2004 Red Hat, Inc.
This file is part of Cygwin.
This software is a copyrighted work licensed under the terms of the
Cygwin license. Please consult the file "CYGWIN_LICENSE" for
details. */
#include "winsup.h"
#include <sys/termios.h>
#include <unistd.h>
#include <cygwin/rdevio.h>
#include <sys/mtio.h>
#include <ntdef.h>
#include "cygerrno.h"
#include "perprocess.h"
#include "security.h"
#include "path.h"
#include "fhandler.h"
#include "dtable.h"
#include "cygheap.h"
#include "ntdll.h"
/**********************************************************************/
/* fhandler_dev_raw */
void
fhandler_dev_raw::clear (void)
{
devbuf = NULL;
devbufsiz = 0;
devbufstart = 0;
devbufend = 0;
eom_detected = 0;
eof_detected = 0;
lastblk_to_read = 0;
}
int
fhandler_dev_raw::is_eom (int win_error)
{
return 0;
}
int
fhandler_dev_raw::is_eof (int)
{
return 0;
}
/* Wrapper functions to allow fhandler_dev_tape to detect and care for
media changes and bus resets. */
BOOL
fhandler_dev_raw::write_file (const void *buf, DWORD to_write,
DWORD *written, int *err)
{
BOOL ret;
*err = 0;
if (!(ret = WriteFile (get_handle (), buf, to_write, written, 0)))
*err = GetLastError ();
syscall_printf ("%d (err %d) = WriteFile (%d, %d, write %d, written %d, 0)",
ret, *err, get_handle (), buf, to_write, *written);
return ret;
}
BOOL
fhandler_dev_raw::read_file (void *buf, DWORD to_read, DWORD *read, int *err)
{
BOOL ret;
*err = 0;
if (!(ret = ReadFile (get_handle (), buf, to_read, read, 0)))
*err = GetLastError ();
syscall_printf ("%d (err %d) = ReadFile (%d, %d, to_read %d, read %d, 0)",
ret, *err, get_handle (), buf, to_read, *read);
return ret;
}
int
fhandler_dev_raw::writebuf (void)
{
DWORD written;
int ret = 0;
if (is_writing && devbuf && devbufend)
{
DWORD to_write;
int ret = 0;
memset (devbuf + devbufend, 0, devbufsiz - devbufend);
to_write = ((devbufend - 1) / 512 + 1) * 512;
if (!write_file (devbuf, to_write, &written, &ret)
&& is_eom (ret))
eom_detected = 1;
if (written)
has_written = 1;
devbufstart = devbufend = 0;
}
is_writing = 0;
return ret;
}
fhandler_dev_raw::fhandler_dev_raw ()
: fhandler_base ()
{
clear ();
set_need_fork_fixup ();
}
fhandler_dev_raw::~fhandler_dev_raw (void)
{
if (devbufsiz > 1L)
delete [] devbuf;
clear ();
}
int __stdcall
fhandler_dev_raw::fstat (struct __stat64 *buf)
{
debug_printf ("here");
if (get_major () == DEV_TAPE_MAJOR)
buf->st_mode = S_IFCHR | STD_RBITS | STD_WBITS | S_IWGRP | S_IWOTH;
else
buf->st_mode = S_IFBLK | STD_RBITS | STD_WBITS | S_IWGRP | S_IWOTH;
buf->st_uid = geteuid32 ();
buf->st_gid = getegid32 ();
buf->st_nlink = 1;
buf->st_blksize = S_BLKSIZE;
time_as_timestruc_t (&buf->st_ctim);
buf->st_atim = buf->st_mtim = buf->st_ctim;
return 0;
}
int
fhandler_dev_raw::open (int flags, mode_t)
{
if (!wincap.has_raw_devices ())
{
set_errno (ENOENT);
debug_printf ("%s is accessible under NT/W2K only", get_win32_name ());
return 0;
}
/* Check for illegal flags. */
if (get_major () != DEV_TAPE_MAJOR && (flags & (O_APPEND | O_EXCL)))
{
set_errno (EINVAL);
return 0;
}
/* Always open a raw device existing and binary. */
flags &= ~(O_CREAT | O_TRUNC);
flags |= O_BINARY;
DWORD access = GENERIC_READ | SYNCHRONIZE;
if (get_major () == DEV_TAPE_MAJOR
|| (flags & (O_RDONLY | O_WRONLY | O_RDWR)) == O_WRONLY
|| (flags & (O_RDONLY | O_WRONLY | O_RDWR)) == O_RDWR)
access |= GENERIC_WRITE;
extern void str2buf2uni (UNICODE_STRING &, WCHAR *, const char *);
UNICODE_STRING dev;
WCHAR devname[CYG_MAX_PATH + 1];
str2buf2uni (dev, devname, get_win32_name ());
OBJECT_ATTRIBUTES attr;
ULONG options = FILE_SYNCHRONOUS_IO_NONALERT;
/* The O_TEXT flag is used to indicate write-through on tape devices */
if (get_major () == DEV_TAPE_MAJOR && (flags & O_TEXT))
options |= FILE_WRITE_THROUGH;
flags &= ~O_TEXT;
InitializeObjectAttributes (&attr, &dev, OBJ_CASE_INSENSITIVE, NULL, NULL);
HANDLE h;
IO_STATUS_BLOCK io;
NTSTATUS status = NtOpenFile (&h, access, &attr, &io, 0 /* excl. access */,
FILE_SYNCHRONOUS_IO_NONALERT);
if (!NT_SUCCESS (status))
{
__seterrno_from_win_error (RtlNtStatusToDosError (status));
return 0;
}
set_io_handle (h);
set_flags ((flags & ~O_TEXT) | O_BINARY);
if (devbufsiz > 1L)
devbuf = new char [devbufsiz];
return 1;
}
int
fhandler_dev_raw::close (void)
{
return fhandler_base::close ();
}
void
fhandler_dev_raw::raw_read (void *ptr, size_t& ulen)
{
DWORD bytes_read = 0;
DWORD read2;
DWORD bytes_to_read;
int ret;
size_t len = ulen;
char *tgt;
char *p = (char *) ptr;
/* In mode O_RDWR the buffer has to be written to device first */
ret = writebuf ();
if (ret)
{
if (is_eom (ret))
set_errno (ENOSPC);
else
__seterrno ();
goto err;
}
/* Checking a previous end of file */
if (eof_detected && !lastblk_to_read)
{
eof_detected = 0;
ulen = 0;
return;
}
/* Checking a previous end of media */
if (eom_detected && !lastblk_to_read)
{
set_errno (ENOSPC);
goto err;
}
if (devbuf)
{
while (len > 0)
{
if (devbufstart < devbufend)
{
bytes_to_read = min (len, devbufend - devbufstart);
debug_printf ("read %d bytes from buffer (rest %d)",
bytes_to_read,
devbufend - devbufstart - bytes_to_read);
memcpy (p, devbuf + devbufstart, bytes_to_read);
len -= bytes_to_read;
p += bytes_to_read;
bytes_read += bytes_to_read;
devbufstart += bytes_to_read;
if (lastblk_to_read)
{
lastblk_to_read = 0;
break;
}
}
if (len > 0)
{
if (len >= devbufsiz)
{
bytes_to_read = (len / 512) * 512;
tgt = p;
debug_printf ("read %d bytes direct from file",bytes_to_read);
}
else
{
tgt = devbuf;
bytes_to_read = devbufsiz;
debug_printf ("read %d bytes from file into buffer",
bytes_to_read);
}
if (!read_file (tgt, bytes_to_read, &read2, &ret))
{
if (!is_eof (ret) && !is_eom (ret))
{
__seterrno ();
goto err;
}
if (is_eof (ret))
eof_detected = 1;
else
eom_detected = 1;
if (!read2)
{
if (!bytes_read && is_eom (ret))
{
debug_printf ("return -1, set errno to ENOSPC");
set_errno (ENOSPC);
goto err;
}
break;
}
lastblk_to_read = 1;
}
if (!read2)
break;
if (tgt == devbuf)
{
devbufstart = 0;
devbufend = read2;
}
else
{
len -= read2;
p += read2;
bytes_read += read2;
}
}
}
}
else if (!read_file (p, len, &bytes_read, &ret))
{
if (!is_eof (ret) && !is_eom (ret))
{
__seterrno ();
goto err;
}
if (bytes_read)
{
if (is_eof (ret))
eof_detected = 1;
else
eom_detected = 1;
}
else if (is_eom (ret))
{
debug_printf ("return -1, set errno to ENOSPC");
set_errno (ENOSPC);
goto err;
}
}
ulen = (size_t) bytes_read;
return;
err:
ulen = (size_t) -1;
return;
}
int
fhandler_dev_raw::raw_write (const void *ptr, size_t len)
{
DWORD bytes_written = 0;
DWORD bytes_to_write;
DWORD written;
char *p = (char *) ptr;
char *tgt;
int ret;
/* Checking a previous end of media on tape */
if (eom_detected)
{
set_errno (ENOSPC);
return -1;
}
if (!is_writing)
devbufstart = devbufend = 0;
is_writing = 1;
if (devbuf)
{
while (len > 0)
{
if ((len < devbufsiz || devbufend > 0) && devbufend < devbufsiz)
{
bytes_to_write = min (len, devbufsiz - devbufend);
memcpy (devbuf + devbufend, p, bytes_to_write);
bytes_written += bytes_to_write;
devbufend += bytes_to_write;
p += bytes_to_write;
len -= bytes_to_write;
}
else
{
if (devbufend == devbufsiz)
{
bytes_to_write = devbufsiz;
tgt = devbuf;
}
else
{
bytes_to_write = (len / devbufsiz) * devbufsiz;
tgt = p;
}
ret = 0;
write_file (tgt, bytes_to_write, &written, &ret);
if (written)
has_written = 1;
if (ret)
{
if (!is_eom (ret))
{
__seterrno ();
return -1;
}
eom_detected = 1;
if (!written && !bytes_written)
{
set_errno (ENOSPC);
return -1;
}
if (tgt == p)
bytes_written += written;
break; // from while (len > 0)
}
if (tgt == devbuf)
{
if (written != devbufsiz)
memmove (devbuf, devbuf + written, devbufsiz - written);
devbufend = devbufsiz - written;
}
else
{
len -= written;
p += written;
bytes_written += written;
}
}
}
}
else if (len > 0)
{
if (!write_file (p, len, &bytes_written, &ret))
{
if (bytes_written)
has_written = 1;
if (!is_eom (ret))
{
__seterrno ();
return -1;
}
eom_detected = 1;
if (!bytes_written)
{
set_errno (ENOSPC);
return -1;
}
}
has_written = 1;
}
return bytes_written;
}
int
fhandler_dev_raw::dup (fhandler_base *child)
{
int ret = fhandler_base::dup (child);
if (! ret)
{
fhandler_dev_raw *fhc = (fhandler_dev_raw *) child;
fhc->devbufsiz = devbufsiz;
if (devbufsiz > 1L)
fhc->devbuf = new char [devbufsiz];
fhc->devbufstart = 0;
fhc->devbufend = 0;
fhc->eom_detected = eom_detected;
fhc->eof_detected = eof_detected;
fhc->lastblk_to_read = 0;
}
return ret;
}
void
fhandler_dev_raw::fixup_after_fork (HANDLE)
{
devbufstart = 0;
devbufend = 0;
lastblk_to_read = 0;
}
void
fhandler_dev_raw::fixup_after_exec ()
{
if (devbufsiz > 1L)
devbuf = new char [devbufsiz];
devbufstart = 0;
devbufend = 0;
lastblk_to_read = 0;
}
int
fhandler_dev_raw::ioctl (unsigned int cmd, void *buf)
{
int ret = NO_ERROR;
if (cmd == RDIOCDOP)
{
struct rdop *op = (struct rdop *) buf;
if (!op)
ret = ERROR_INVALID_PARAMETER;
else
switch (op->rd_op)
{
case RDSETBLK:
if (get_major () == DEV_TAPE_MAJOR)
{
struct mtop mop;
mop.mt_op = MTSETBLK;
mop.mt_count = op->rd_parm;
ret = ioctl (MTIOCTOP, &mop);
}
else if (op->rd_parm % 512)
ret = ERROR_INVALID_PARAMETER;
else if (devbuf && op->rd_parm < devbufend - devbufstart)
ret = ERROR_INVALID_PARAMETER;
else if (!devbuf || op->rd_parm != devbufsiz)
{
char *buf = new char [op->rd_parm];
if (devbufsiz > 1L)
{
memcpy (buf, devbuf + devbufstart, devbufend - devbufstart);
devbufend -= devbufstart;
delete [] devbuf;
}
else
devbufend = 0;
devbufstart = 0;
devbuf = buf;
devbufsiz = op->rd_parm;
}
break;
default:
break;
}
}
else if (cmd == RDIOCGET)
{
struct rdget *get = (struct rdget *) buf;
if (!get)
ret = ERROR_INVALID_PARAMETER;
else
get->bufsiz = devbufsiz ? devbufsiz : 1L;
}
else
return fhandler_base::ioctl (cmd, buf);
if (ret != NO_ERROR)
{
SetLastError (ret);
__seterrno ();
return -1;
}
return 0;
}