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/* ----------------------------------------------------------------------- *
*
* Copyright 2003-2008 H. Peter Anvin - All Rights Reserved
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use,
* copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom
* the Software is furnished to do so, subject to the following
* conditions:
*
* The above copyright notice and this permission notice shall
* be included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*
* ----------------------------------------------------------------------- */
#include <errno.h>
#include <com32.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <stdlib.h>
#include "file.h"
/*
* open.c
*
* Open an ordinary file
*/
extern ssize_t __file_read(struct file_info *, void *, size_t);
extern int __file_close(struct file_info *);
const struct input_dev __file_dev = {
.dev_magic = __DEV_MAGIC,
.flags = __DEV_FILE | __DEV_INPUT,
.fileflags = O_RDONLY,
.read = __file_read,
.close = __file_close,
.open = NULL,
};
int open(const char *pathname, int flags, ...)
{
com32sys_t regs;
int fd, e;
struct file_info *fp = NULL;
fd = opendev(&__file_dev, NULL, flags);
if (fd < 0)
goto err;
fp = &__file_info[fd];
fp->i.datap = fp->i.buf = malloc(MAXBLOCK);
if (!fp->i.buf)
goto err;
strlcpy(__com32.cs_bounce, pathname, __com32.cs_bounce_size);
regs.eax.w[0] = 0x0006;
regs.esi.w[0] = OFFS(__com32.cs_bounce);
regs.es = SEG(__com32.cs_bounce);
__com32.cs_intcall(0x22, ®s, ®s);
if ((regs.eflags.l & EFLAGS_CF) || regs.esi.w[0] == 0) {
errno = ENOENT;
goto err;
}
{
uint16_t blklg2;
asm("bsrw %1,%0" : "=r"(blklg2) : "rm"(regs.ecx.w[0]));
fp->i.blocklg2 = blklg2;
}
fp->i.length = regs.eax.l;
fp->i.filedes = regs.esi.w[0];
fp->i.offset = 0;
fp->i.nbytes = 0;
return fd;
err:
e = errno;
if (fp) {
if (fp->i.buf)
free(fp->i.buf);
memset(fp, 0, sizeof *fp); /* Mark file structure unused */
}
errno = e;
return -1;
}
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