/*
* Allocate a file buffer, or switch to unbuffered I/O.
* Per the ANSI C standard, ALL tty devices default to line buffered.
*
* As a side effect, we set __SOPT or __SNPT (en/dis-able fseek
* optimisation) right after the fstat() that finds the buffer size.
*/
void
__smakebuf(FILE *fp)
{
void *p;
int flags;
size_t size;
int couldbetty;
_DIAGASSERT(fp != NULL);
if (fp->_flags & __SNBF) {
fp->_bf._base = fp->_p = fp->_nbuf;
fp->_bf._size = 1;
return;
}
flags = __swhatbuf(fp, &size, &couldbetty);
if ((p = malloc(size)) == NULL) {
fp->_flags |= __SNBF;
fp->_bf._base = fp->_p = fp->_nbuf;
fp->_bf._size = 1;
return;
}
__cleanup = _cleanup;
flags |= __SMBF;
fp->_bf._base = fp->_p = p;
_DIAGASSERT(__type_fit(int, size));
fp->_bf._size = (int)size;
if (couldbetty && isatty(__sfileno(fp)))
flags |= __SLBF;
fp->_flags |= flags;
}
/*
* Allocate a file buffer, or switch to unbuffered I/O.
* Per the ANSI C standard, ALL tty devices default to line buffered.
*
* As a side effect, we set __SOPT or __SNPT (en/dis-able fseek
* optimisation) right after the fstat() that finds the buffer size.
*/
void
__smakebuf(FILE *fp)
{
void *p;
int flags;
size_t size;
int couldbetty;
if (fp->_flags & __SNBF) {
fp->_bf._base = fp->_p = fp->_nbuf;
fp->_bf._size = 1;
return;
}
flags = __swhatbuf(fp, &size, &couldbetty);
if ((p = malloc(size)) == NULL) {
fp->_flags |= __SNBF;
fp->_bf._base = fp->_p = fp->_nbuf;
fp->_bf._size = 1;
return;
}
flags |= __SMBF;
fp->_bf._base = fp->_p = p;
fp->_bf._size = size;
if (couldbetty && isatty(fp->_file))
flags |= __SLBF;
fp->_flags |= flags;
}
/*
* Allocate a file buffer, or switch to unbuffered I/O.
* Per the ANSI C standard, ALL tty devices default to line buffered.
*
* As a side effect, we set __SOPT or __SNPT (en/dis-able fseek
* optimisation) right after the fstat() that finds the buffer size.
*/
void
__smakebuf(FILE *fp)
{
void *p;
int flags;
size_t size;
int couldbetty;
_DIAGASSERT(fp != NULL);
if (fp != NULL) {
if (fp->_flags & __SNBF) {
fp->_bf._base = fp->_p = fp->_nbuf;
fp->_bf._size = MB_LEN_MAX;
return;
}
flags = __swhatbuf(fp, &size, &couldbetty);
if ((p = malloc(size)) == NULL) {
// malloc failed, act unbuffered.
fp->_flags |= __SNBF;
fp->_bf._base = fp->_p = fp->_nbuf;
fp->_bf._size = 1;
return;
}
gMD->cleanup = _cleanup;
flags |= __SMBF;
fp->_bf._base = fp->_p = p;
fp->_bf._size = (int)size;
if (couldbetty || isatty(fp->_file))
flags |= __SLBF;
fp->_flags |= flags;
}
}
/*
* Allocate a file buffer, or switch to unbuffered I/O.
* Per the ANSI C standard, ALL tty devices default to line buffered.
*
* As a side effect, we set __SOPT or __SNPT (en/dis-able fseek
* optimisation) right after the fstat() that finds the buffer size.
*/
void
__smakebuf(FILE *fp)
{
void *p;
int flags;
size_t size;
int couldbetty;
_DIAGASSERT(fp != NULL);
if (fp->_flags & __SNBF)
goto unbuf;
flags = __swhatbuf(fp, &size, &couldbetty);
if ((fp->_flags & (__SLBF|__SNBF|__SMBF)) == 0
&& fp->_cookie == fp && fp->_file >= 0) {
flags |= __senvbuf(fp, &size, &couldbetty);
if (flags & __SNBF)
goto unbuf;
}
if ((p = malloc(size)) == NULL)
goto unbuf;
__cleanup = _cleanup;
flags |= __SMBF;
fp->_bf._base = fp->_p = p;
_DIAGASSERT(__type_fit(int, size));
fp->_bf._size = (int)size;
if (couldbetty && isatty(__sfileno(fp)))
flags |= __SLBF;
fp->_flags |= flags;
return;
unbuf:
fp->_flags |= __SNBF;
fp->_bf._base = fp->_p = fp->_nbuf;
fp->_bf._size = 1;
}
/*
* Set one of the three kinds of buffering, optionally including
* a buffer.
*/
int
setvbuf(FILE *fp, char *buf, int mode, size_t size)
{
int ret, flags;
size_t iosize;
int ttyflag;
/*
* Verify arguments. The `int' limit on `size' is due to this
* particular implementation. Note, buf and size are ignored
* when setting _IONBF.
*/
if (mode != _IONBF)
if ((mode != _IOFBF && mode != _IOLBF) || (int)size < 0)
return (EOF);
/*
* Write current buffer, if any. Discard unread input (including
* ungetc data), cancel line buffering, and free old buffer if
* malloc()ed. We also clear any eof condition, as if this were
* a seek.
*/
ret = 0;
(void)__sflush(fp);
if (HASUB(fp))
FREEUB(fp);
WCIO_FREE(fp);
fp->_r = fp->_lbfsize = 0;
flags = fp->_flags;
if (flags & __SMBF)
free((void *)fp->_bf._base);
flags &= ~(__SLBF | __SNBF | __SMBF | __SOPT | __SNPT | __SEOF);
/* If setting unbuffered mode, skip all the hard work. */
if (mode == _IONBF)
goto nbf;
/*
* Find optimal I/O size for seek optimization. This also returns
* a `tty flag' to suggest that we check isatty(fd), but we do not
* care since our caller told us how to buffer.
*/
flags |= __swhatbuf(fp, &iosize, &ttyflag);
if (size == 0) {
buf = NULL; /* force local allocation */
size = iosize;
}
/* Allocate buffer if needed. */
if (buf == NULL) {
if ((buf = malloc(size)) == NULL) {
/*
* Unable to honor user's request. We will return
* failure, but try again with file system size.
*/
ret = EOF;
if (size != iosize) {
size = iosize;
buf = malloc(size);
}
}
if (buf == NULL) {
/* No luck; switch to unbuffered I/O. */
nbf:
fp->_flags = flags | __SNBF;
fp->_w = 0;
fp->_bf._base = fp->_p = fp->_nbuf;
fp->_bf._size = 1;
return (ret);
}
flags |= __SMBF;
}
/*
* Kill any seek optimization if the buffer is not the
* right size.
*
* SHOULD WE ALLOW MULTIPLES HERE (i.e., ok iff (size % iosize) == 0)?
*/
if (size != iosize)
flags |= __SNPT;
/*
* Fix up the FILE fields, and set __cleanup for output flush on
* exit (since we are buffered in some way).
*/
if (mode == _IOLBF)
flags |= __SLBF;
fp->_flags = flags;
fp->_bf._base = fp->_p = (unsigned char *)buf;
fp->_bf._size = size;
/* fp->_lbfsize is still 0 */
if (flags & __SWR) {
/*
* Begin or continue writing: see __swsetup(). Note
* that __SNBF is impossible (it was handled earlier).
*/
if (flags & __SLBF) {
fp->_w = 0;
fp->_lbfsize = -fp->_bf._size;
} else
fp->_w = size;
} else {
/* begin/continue reading, or stay in intermediate state */
fp->_w = 0;
}
__atexit_register_cleanup(_cleanup);
return (ret);
}
