newlib-cygwin/newlib/libc/sys/mmixware/open.c

107 lines
2.6 KiB
C

/* open for MMIXware.
Copyright (C) 2001 Hans-Peter Nilsson.
Permission to use, copy, modify, and distribute this software is freely
granted, provided that this notice is preserved with no changes.
THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
PURPOSE. */
#include <fcntl.h>
#include <_ansi.h>
#include <sys/types.h>
#include <sys/stat.h>
#include "sys/syscall.h"
#include <errno.h>
/* Let's keep the filehandle array here, since this is a primary
initializer of it. */
unsigned char _MMIX_allocated_filehandle[32] =
{
1,
1,
1,
0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0
};
int
_open (const char *path,
int flags, ...)
{
long fileno;
unsigned char mode;
long fffile = 0;
long ret;
for (fileno = 0;
fileno < (sizeof (_MMIX_allocated_filehandle) /
sizeof (_MMIX_allocated_filehandle[0]));
fileno++)
if (_MMIX_allocated_filehandle[fileno] == 0)
break;
if (fileno == (sizeof (_MMIX_allocated_filehandle) /
sizeof (_MMIX_allocated_filehandle[0])))
{
errno = EMFILE;
return -1;
}
/* We map this to a fopen call. The flags parameter is stymied because
we don't support more other than these flags. */
if (flags & ~(O_RDONLY | O_WRONLY | O_RDWR | O_CREAT | O_APPEND | O_TRUNC))
{
UNIMPLEMENTED (("path: %s, flags: %d", path, flags));
errno = ENOSYS;
return -1;
}
if ((flags & O_ACCMODE) == O_RDONLY)
mode = BinaryRead;
else if ((flags & (O_WRONLY | O_APPEND)) == (O_WRONLY | O_APPEND))
{
mode = BinaryReadWrite;
fffile = 1;
}
else if ((flags & (O_RDWR | O_APPEND)) == (O_RDWR | O_APPEND))
{
mode = BinaryReadWrite;
fffile = 1;
}
else if ((flags & (O_WRONLY | O_CREAT)) == (O_WRONLY | O_CREAT)
|| (flags & (O_WRONLY | O_TRUNC)) == (O_WRONLY | O_TRUNC))
mode = BinaryWrite;
else if ((flags & (O_RDWR | O_CREAT)) == (O_RDWR | O_CREAT))
mode = BinaryReadWrite;
else if (flags & O_RDWR)
mode = BinaryReadWrite;
else
{
errno = EINVAL;
return -1;
}
ret = TRAP3f (SYS_Fopen, fileno, path, mode);
if (ret < 0)
{
/* It's totally unknown what the error was. We'll just take our
chances and assume ENOENT. */
errno = ENOENT;
return -1;
}
_MMIX_allocated_filehandle[fileno] = 1;
if (fffile)
{
TRAP2f (SYS_Fseek, fileno, -1);
}
return fileno;
}