off_t lseek(int fid, off_t offset, int whence)
{
off_t rc;
FILE *file;
#if OS_PARM_CHECK
/*-------------------------------------------------------------------*/
/* If the file descriptor is invalid, return error. */
/*-------------------------------------------------------------------*/
if (fid < 0 || fid >= FOPEN_MAX)
{
set_errno(EBADF);
return -1;
}
if (Files[fid].flags & FCB_DIR)
{
set_errno(EISDIR);
return -1;
}
#endif
/*-------------------------------------------------------------------*/
/* Get exclusive access to upper file system. */
/*-------------------------------------------------------------------*/
semPend(FileSysSem, WAIT_FOREVER);
/*-------------------------------------------------------------------*/
/* Return error if file is closed. */
/*-------------------------------------------------------------------*/
file = &Files[fid];
if (file->ioctl == NULL)
{
set_errno(EBADF);
semPost(FileSysSem);
return -1;
}
/*-------------------------------------------------------------------*/
/* Acquire exclusive access to lower file system. */
/*-------------------------------------------------------------------*/
file->acquire(file, F_READ | F_WRITE);
/*-------------------------------------------------------------------*/
/* Call file system specific FSEEK routine. */
/*-------------------------------------------------------------------*/
rc = (off_t)file->ioctl(file, FSEEK, (long)offset, whence);
/*-------------------------------------------------------------------*/
/* Release exclusive access to file systems and return result. */
/*-------------------------------------------------------------------*/
file->release(file, F_READ | F_WRITE);
semPost(FileSysSem);
return rc;
}
int fcntl(int fid, int cmd, ...)
{
va_list ap;
FILE *file;
#if OS_PARM_CHECK
/*-------------------------------------------------------------------*/
/* If the file descriptor is invalid, return error. */
/*-------------------------------------------------------------------*/
if (fid < 0 || fid >= FOPEN_MAX)
{
set_errno(EBADF);
return -1;
}
#endif
/*-------------------------------------------------------------------*/
/* Get exclusive access to upper file system. */
/*-------------------------------------------------------------------*/
semPend(FileSysSem, WAIT_FOREVER);
/*-------------------------------------------------------------------*/
/* Return error if file is closed. */
/*-------------------------------------------------------------------*/
file = &Files[fid];
if (file->ioctl == NULL)
{
semPost(FileSysSem);
set_errno(EBADF);
return -1;
}
/*-------------------------------------------------------------------*/
/* Based on the command, execute the right instructions. */
/*-------------------------------------------------------------------*/
switch (cmd)
{
case F_DUPFD:
{
/*---------------------------------------------------------------*/
/* Use the va_arg mechanism to get the argument. */
/*---------------------------------------------------------------*/
va_start(ap, cmd);
fid = va_arg(ap, int);
va_end(ap);
#if OS_PARM_CHECK
/*---------------------------------------------------------------*/
/* If the file descriptor is invalid, return error. */
/*---------------------------------------------------------------*/
if (fid < 0 || fid >= FOPEN_MAX)
{
semPost(FileSysSem);
set_errno(EINVAL);
return -1;
}
#endif
/*---------------------------------------------------------------*/
/* Look for free file control block identifier >= fid. */
/*---------------------------------------------------------------*/
for (;;)
{
FILE *file2 = &Files[fid];
/*-------------------------------------------------------------*/
/* Check if file control block is free. */
/*-------------------------------------------------------------*/
if (file2->ioctl == NULL)
{
/*-----------------------------------------------------------*/
/* Copy previous file control block to new one. */
/*-----------------------------------------------------------*/
*file2 = *file;
/*-----------------------------------------------------------*/
/* Acquire exclusive access to lower file system. */
/*-----------------------------------------------------------*/
file2->acquire(file2, F_READ | F_WRITE);
/*-----------------------------------------------------------*/
/* Call file system specific DUP routine. */
/*-----------------------------------------------------------*/
file2->ioctl(file2, DUP);
/*-----------------------------------------------------------*/
/* Release exclusive access to lower file system. */
/*-----------------------------------------------------------*/
file2->release(file2, F_READ | F_WRITE);
break;
}
/*-------------------------------------------------------------*/
/* If none are free, set errno and break. */
/*-------------------------------------------------------------*/
if (++fid >= FOPEN_MAX)
{
set_errno(EMFILE);
fid = -1;
break;
}
}
/*---------------------------------------------------------------*/
/* Release access to upper file system and return result. */
/*---------------------------------------------------------------*/
semPost(FileSysSem);
return fid;
}
case F_SETFL:
{
int oflag, r_val;
/*---------------------------------------------------------------*/
/* Acquire exclusive access to lower file system. */
/*---------------------------------------------------------------*/
file->acquire(file, F_READ | F_WRITE);
/*---------------------------------------------------------------*/
/* Use the va_arg mechanism to get the argument. */
/*---------------------------------------------------------------*/
va_start(ap, cmd);
oflag = va_arg(ap, int);
va_end(ap);
/*---------------------------------------------------------------*/
/* Call specific ioctl to set flag. */
/*---------------------------------------------------------------*/
r_val = (int)file->ioctl(file, SET_FL, oflag);
/*---------------------------------------------------------------*/
/* Release exclusive access to lower file system. */
/*---------------------------------------------------------------*/
file->release(file, F_READ | F_WRITE);
/*---------------------------------------------------------------*/
/* Release access to upper file system and return result. */
/*---------------------------------------------------------------*/
semPost(FileSysSem);
return r_val;
}
case F_GETFL:
{
int r_val;
/*---------------------------------------------------------------*/
/* Acquire exclusive access to lower file system. */
/*---------------------------------------------------------------*/
file->acquire(file, F_READ);
/*---------------------------------------------------------------*/
/* Call specific ioctl to get flag. */
/*---------------------------------------------------------------*/
r_val = (int)file->ioctl(file, GET_FL);
/*---------------------------------------------------------------*/
/* Release exclusive access to lower file system. */
/*---------------------------------------------------------------*/
file->release(file, F_READ);
/*---------------------------------------------------------------*/
/* Release access to upper file system and return result. */
/*---------------------------------------------------------------*/
semPost(FileSysSem);
return r_val;
}
}
/*-------------------------------------------------------------------*/
/* An unsupported command was requested. */
/*-------------------------------------------------------------------*/
set_errno(EINVAL);
semPost(FileSysSem);
return -1;
}
int creatn(const char *path, mode_t mode, size_t size)
{
int rv = -1;
void *dir;
FILE *file;
#if !_PATH_NO_TRUNC
char trunc_path[PATH_MAX + 1];
#endif
#if OS_PARM_CHECK
/*-------------------------------------------------------------------*/
/* If path is NULL, return -1. */
/*-------------------------------------------------------------------*/
if (path == NULL)
{
set_errno(EFAULT);
return -1;
}
#endif
/*-------------------------------------------------------------------*/
/* Acquire exclusive access to upper file system. */
/*-------------------------------------------------------------------*/
semPend(FileSysSem, WAIT_FOREVER);
/*-------------------------------------------------------------------*/
/* Find a free file control block and initialize it. */
/*-------------------------------------------------------------------*/
for (file = &Files[0]; file->ioctl; ++file)
{
/*-----------------------------------------------------------------*/
/* If none are free, return error. */
/*-----------------------------------------------------------------*/
if (file == &Files[FOPEN_MAX - 1])
{
set_errno(EMFILE);
semPost(FileSysSem);
return -1;
}
}
FsInitFCB(file, FCB_FILE);
/*-------------------------------------------------------------------*/
/* Ensure path is valid. */
/*-------------------------------------------------------------------*/
dir = FSearch(file, &path, PARENT_DIR);
if (dir == NULL)
goto end;
/*-------------------------------------------------------------------*/
/* If path too long, return error if no truncation, else truncate. */
/*-------------------------------------------------------------------*/
if (strlen(path) > PATH_MAX)
{
#if _PATH_NO_TRUNC
set_errno(ENAMETOOLONG);
goto end;
#else
strncpy(trunc_path, path, PATH_MAX);
trunc_path[PATH_MAX] = '\0';
path = trunc_path;
#endif
}
/*-------------------------------------------------------------------*/
/* Acquire exclusive access to lower file system. */
/*-------------------------------------------------------------------*/
file->acquire(file, F_READ | F_WRITE);
/*-------------------------------------------------------------------*/
/* Call file system specific CREATN routine. */
/*-------------------------------------------------------------------*/
rv = (int)file->ioctl(file, CREATN, path, mode, size, dir);
/*-------------------------------------------------------------------*/
/* Release exclusive access to lower file system. */
/*-------------------------------------------------------------------*/
file->release(file, F_READ | F_WRITE);
/*-------------------------------------------------------------------*/
/* Free control block if error, else set return value. */
/*-------------------------------------------------------------------*/
end:
if (rv == -1)
file->ioctl = NULL;
else
rv = file - &Files[0];
/*-------------------------------------------------------------------*/
/* Release exclusive access to upper file system and return result. */
/*-------------------------------------------------------------------*/
semPost(FileSysSem);
return rv;
}
int write(int fid, const void *buf, unsigned int nbytes)
{
int written;
FILE *file;
#if OS_PARM_CHECK
/*-------------------------------------------------------------------*/
/* Ensure file descriptor is valid. */
/*-------------------------------------------------------------------*/
if (fid < 0 || fid >= FOPEN_MAX)
{
set_errno(EBADF);
return -1;
}
/*-------------------------------------------------------------------*/
/* Return error if buffer pointer is invalid. */
/*-------------------------------------------------------------------*/
if (buf == NULL)
{
Files[fid].errcode = EFAULT;
set_errno(EFAULT);
return -1;
}
#endif
/*-------------------------------------------------------------------*/
/* Acquire exclusive write access to stream. */
/*-------------------------------------------------------------------*/
file = &Files[fid];
file->acquire(file, F_WRITE);
/*-------------------------------------------------------------------*/
/* Return error if file is closed. */
/*-------------------------------------------------------------------*/
if (file->ioctl == NULL)
{
set_errno(EBADF);
file->release(file, F_WRITE);
return -1;
}
/*-------------------------------------------------------------------*/
/* Call file system specific write routine. */
/*-------------------------------------------------------------------*/
written = file->write(file, buf, nbytes);
/*-------------------------------------------------------------------*/
/* Set file's errno if less than requested number was written. */
/*-------------------------------------------------------------------*/
if (written < (int)nbytes)
{
file->errcode = get_errno();
if (written == 0)
written = -1;
}
/*-------------------------------------------------------------------*/
/* Release exclusive write access to stream. */
/*-------------------------------------------------------------------*/
file->release(file, F_WRITE);
/*-------------------------------------------------------------------*/
/* Return -1 or actual number of bytes read. */
/*-------------------------------------------------------------------*/
return written;
}
int read(int fid, void *buf, unsigned int nbytes)
{
int hchar = 0, read = 0;
FILE *file;
/*-------------------------------------------------------------------*/
/* If number of requested bytes is zero, return zero. */
/*-------------------------------------------------------------------*/
if (nbytes == 0)
return 0;
#if OS_PARM_CHECK
/*-------------------------------------------------------------------*/
/* Ensure file descriptor is valid. */
/*-------------------------------------------------------------------*/
if (fid < 0 || fid >= FOPEN_MAX)
{
set_errno(EBADF);
return -1;
}
/*-------------------------------------------------------------------*/
/* Return error if buffer pointer is invalid. */
/*-------------------------------------------------------------------*/
if (buf == NULL)
{
Files[fid].errcode = EFAULT;
set_errno(EFAULT);
return -1;
}
#endif
/*-------------------------------------------------------------------*/
/* Acquire exclusive read access to file. */
/*-------------------------------------------------------------------*/
file = &Files[fid];
file->acquire(file, F_READ);
/*-------------------------------------------------------------------*/
/* Return error if file is closed. */
/*-------------------------------------------------------------------*/
if (file->ioctl == NULL)
{
set_errno(EBADF);
file->release(file, F_READ);
return -1;
}
/*-------------------------------------------------------------------*/
/* If available, read pushed-back character first. */
/*-------------------------------------------------------------------*/
if (file->hold_char)
{
ui8 *cp = buf;
*cp = (ui8)file->hold_char;
buf = cp + 1;
file->hold_char = 0;
hchar = 1;
--nbytes;
}
/*-------------------------------------------------------------------*/
/* Check if there are more characters to read. */
/*-------------------------------------------------------------------*/
if (nbytes)
{
/*-----------------------------------------------------------------*/
/* Pass read request to file system or device driver. */
/*-----------------------------------------------------------------*/
read = file->read(file, buf, nbytes);
/*-----------------------------------------------------------------*/
/* Read error is disregarded iff pushed-back character was read. */
/*-----------------------------------------------------------------*/
if (read == -1)
{
if (hchar)
read = 0;
else
file->errcode = get_errno();
}
}
/*-------------------------------------------------------------------*/
/* Release exclusive read access to file. */
/*-------------------------------------------------------------------*/
file->release(file, F_READ);
/*-------------------------------------------------------------------*/
/* Return number of bytes successfully read or -1. */
/*-------------------------------------------------------------------*/
return read + hchar;
}
