newlib-cygwin/winsup/cygwin/fhandler_raw.cc

538 lines
11 KiB
C++

/* fhandler_raw.cc. See fhandler.h for a description of the fhandler classes.
Copyright 1999, 2000 Cygnus Solutions.
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 <sys/termios.h>
#include <fcntl.h>
#include <errno.h>
#include <unistd.h>
#include "winsup.h"
#include <cygwin/rdevio.h>
#include <sys/mtio.h>
/* static wrapper functions to hide the effect of media changes and
bus resets which occurs after a new media is inserted. This is
also related to the used tape device. */
static BOOL write_file (HANDLE fh, const void *buf, DWORD to_write,
DWORD *written, int *err)
{
BOOL ret;
*err = 0;
if (!(ret = WriteFile (fh, buf, to_write, written, 0)))
{
if ((*err = GetLastError ()) == ERROR_MEDIA_CHANGED
|| *err == ERROR_BUS_RESET)
{
*err = 0;
if (!(ret = WriteFile (fh, buf, to_write, written, 0)))
*err = GetLastError ();
}
}
syscall_printf ("%d (err %d) = WriteFile (%d, %d, write %d, written %d, 0)",
ret, *err, fh, buf, to_write, *written);
return ret;
}
static BOOL read_file (HANDLE fh, void *buf, DWORD to_read,
DWORD *read, int *err)
{
BOOL ret;
*err = 0;
if (!(ret = ReadFile(fh, buf, to_read, read, 0)))
{
if ((*err = GetLastError ()) == ERROR_MEDIA_CHANGED
|| *err == ERROR_BUS_RESET)
{
*err = 0;
if (!(ret = ReadFile (fh, buf, to_read, read, 0)))
*err = GetLastError ();
}
}
syscall_printf ("%d (err %d) = ReadFile (%d, %d, to_read %d, read %d, 0)",
ret, *err, fh, buf, to_read, *read);
return ret;
}
/**********************************************************************/
/* 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;
varblkop = 0;
unit = 0;
}
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);
if (get_device () != FH_TAPE)
to_write = ((devbufend - 1) / 512 + 1) * 512;
else if (varblkop)
to_write = devbufend;
else
to_write = devbufsiz;
if (!write_file (get_handle (), 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 (DWORD devtype, const char *name, int unit) : fhandler_base (devtype, name)
{
clear ();
this->unit = unit;
}
fhandler_dev_raw::~fhandler_dev_raw (void)
{
delete[]devbuf;
clear ();
}
int
fhandler_dev_raw::de_linearize (const char *buf, const char *unix_name,
const char *win32_name)
{
int ret = fhandler_base::de_linearize (buf, unix_name, win32_name);
if (devbufsiz > 1L)
{
devbuf = new char[devbufsiz];
devbufstart = devbufend = 0;
}
return ret;
}
int
fhandler_dev_raw::open (const char *path, int flags, mode_t)
{
path_conv real_path (path, PC_SYM_IGNORE);
int ret;
set_name (path, real_path.get_win32 ());
/* Always open a raw device existing */
ret = fhandler_base::open (path, flags & ~(O_CREAT | O_TRUNC));
if (ret)
{
if (devbufsiz > 1L)
devbuf = new char[devbufsiz];
}
else
devbufsiz = 0;
return ret;
}
int
fhandler_dev_raw::close (void)
{
return fhandler_base::close ();
}
int
fhandler_dev_raw::fstat (struct stat *buf)
{
if (!buf)
{
set_errno (EINVAL);
return -1;
}
memset (buf, 0, sizeof *buf);
buf->st_mode = S_IFCHR |
S_IRUSR | S_IWUSR |
S_IRGRP | S_IWGRP |
S_IROTH | S_IWOTH;
buf->st_nlink = 1;
buf->st_blksize = devbuf ? devbufsiz : 1;
buf->st_dev = buf->st_rdev = get_device () << 8 | (unit & 0xff);
return 0;
}
int
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;
/* In mode O_RDWR the buffer has to be written to device first */
ret = writebuf ();
if (ret)
{
set_errno (is_eom (ret) ? ENOSPC : EACCES);
return -1;
}
/* Checking a previous end of file */
if (eof_detected && !lastblk_to_read)
{
eof_detected = 0;
return 0;
}
/* Checking a previous end of media */
if (eom_detected && !lastblk_to_read)
{
set_errno (ENOSPC);
return -1;
}
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, devbufstart - devbufend);
memcpy (ptr, devbuf + devbufstart, bytes_to_read);
len -= bytes_to_read;
ptr = (void *) ((char *) ptr + 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 (!varblkop && len >= devbufsiz)
{
if (get_device () == FH_TAPE)
bytes_to_read = (len / devbufsiz) * devbufsiz;
else
bytes_to_read = (len / 512) * 512;
tgt = (char *) ptr;
debug_printf ("read %d bytes direct from file",bytes_to_read);
}
else
{
bytes_to_read = devbufsiz;
tgt = devbuf;
if (varblkop)
debug_printf ("read variable bytes from file into buffer");
else
debug_printf ("read %d bytes from file into buffer",
bytes_to_read);
}
if (!read_file (get_handle (), tgt, bytes_to_read, &read2, &ret))
{
if (!is_eof (ret) && !is_eom (ret))
{
debug_printf ("return -1, set errno to EACCES");
set_errno (EACCES);
return -1;
}
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);
return -1;
}
break;
}
lastblk_to_read = 1;
}
if (! read2)
break;
if (tgt == devbuf)
{
devbufstart = 0;
devbufend = read2;
}
else
{
len -= bytes_to_read;
ptr = (void *) ((char *) ptr + bytes_to_read);
bytes_read += bytes_to_read;
}
}
}
}
else if (!read_file (get_handle (), ptr, len, &bytes_read, &ret))
{
if (!is_eof (ret) && !is_eom (ret))
{
debug_printf ("return -1, set errno to EACCES");
set_errno (EACCES);
return -1;
}
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);
return -1;
}
}
return bytes_read;
}
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 (!varblkop &&
(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 (varblkop)
{
bytes_to_write = len;
tgt = p;
}
else if (devbufend == devbufsiz)
{
bytes_to_write = devbufsiz;
tgt = devbuf;
}
else
{
bytes_to_write = (len / devbufsiz) * devbufsiz;
tgt = p;
}
ret = 0;
write_file (get_handle (), 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 (get_handle (), ptr, len, &bytes_written, &ret))
{
if (bytes_written)
has_written = 1;
if (!is_eom (ret))
{
set_errno (EACCES);
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];
memcpy (fhc->devbuf, devbuf, devbufend);
}
fhc->devbufstart = devbufstart;
fhc->devbufend = devbufend;
fhc->eom_detected = eom_detected;
fhc->eof_detected = eof_detected;
fhc->lastblk_to_read = lastblk_to_read;
fhc->varblkop = varblkop;
fhc->unit = unit;
}
return ret;
}
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_device () == FH_TAPE)
{
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 (devbuf)
{
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;
}