/*
* Various output routines call wsetup to be sure it is safe to write,
* because either _flags does not include __SWR, or _buf is NULL.
* _wsetup returns 0 if OK to write, nonzero otherwise.
*/
int
__swsetup(FILE *fp)
{
/* make sure stdio is set up */
if (!__sdidinit)
__sinit();
/*
* If we are not writing, we had better be reading and writing.
*/
if ((fp->_flags & __SWR) == 0) {
if ((fp->_flags & __SRW) == 0)
return (EOF);
if (fp->_flags & __SRD) {
/* clobber any ungetc data */
if (HASUB(fp))
FREEUB(fp);
fp->_flags &= ~(__SRD|__SEOF);
fp->_r = 0;
fp->_p = fp->_bf._base;
}
fp->_flags |= __SWR;
}
/*
* Make a buffer if necessary, then set _w.
*/
if (fp->_bf._base == NULL) {
if ((fp->_flags & (__SSTR | __SALC)) == __SSTR)
return (EOF);
__smakebuf(fp);
}
if (fp->_flags & __SLBF) {
/*
* It is line buffered, so make _lbfsize be -_bufsize
* for the putc() macro. We will change _lbfsize back
* to 0 whenever we turn off __SWR.
*/
fp->_w = 0;
fp->_lbfsize = -fp->_bf._size;
} else
fp->_w = fp->_flags & __SNBF ? 0 : fp->_bf._size;
return (0);
}
/*
* Seek the given file to the given offset.
* `Whence' must be one of the three SEEK_* macros.
*/
int
fseeko(FILE *fp, off_t offset, int whence)
{
fpos_t (*seekfn)(void *, fpos_t, int);
fpos_t target, curoff;
size_t n;
struct stat st;
int havepos;
/* make sure stdio is set up */
if (!__sdidinit)
__sinit();
/*
* Have to be able to seek.
*/
if ((seekfn = fp->_seek) == NULL || isatty(__sfileno(fp))) {
__sseterr(fp, ESPIPE); /* historic practice */
return (EOF);
}
/*
* Change any SEEK_CUR to SEEK_SET, and check `whence' argument.
* After this, whence is either SEEK_SET or SEEK_END.
*/
FLOCKFILE(fp);
switch (whence) {
case SEEK_CUR:
/*
* In order to seek relative to the current stream offset,
* we have to first find the current stream offset a la
* ftell (see ftell for details).
*/
__sflush(fp); /* may adjust seek offset on append stream */
if (fp->_flags & __SOFF)
curoff = fp->_offset;
else {
curoff = (*seekfn)(fp->_cookie, (fpos_t)0, SEEK_CUR);
if (curoff == (fpos_t)-1) {
FUNLOCKFILE(fp);
return (EOF);
}
}
if (fp->_flags & __SRD) {
curoff -= fp->_r;
if (HASUB(fp))
curoff -= fp->_ur;
} else if (fp->_flags & __SWR && fp->_p != NULL)
curoff += fp->_p - fp->_bf._base;
offset += curoff;
whence = SEEK_SET;
havepos = 1;
break;
case SEEK_SET:
case SEEK_END:
curoff = 0; /* XXX just to keep gcc quiet */
havepos = 0;
break;
default:
FUNLOCKFILE(fp);
__sseterr(fp, EINVAL);
return (EOF);
}
/*
* Can only optimise if:
* reading (and not reading-and-writing);
* not unbuffered; and
* this is a `regular' Unix file (and hence seekfn==__sseek).
* We must check __NBF first, because it is possible to have __NBF
* and __SOPT both set.
*/
if (fp->_bf._base == NULL)
__smakebuf(fp);
if (fp->_flags & (__SWR | __SRW | __SNBF | __SNPT))
goto dumb;
if ((fp->_flags & __SOPT) == 0) {
if (seekfn != __sseek ||
fp->_file < 0 || __libc_fstat(fp->_file, &st) ||
(st.st_mode & S_IFMT) != S_IFREG) {
fp->_flags |= __SNPT;
goto dumb;
}
fp->_blksize = st.st_blksize;
fp->_flags |= __SOPT;
}
/*
* We are reading; we can try to optimise.
* Figure out where we are going and where we are now.
*/
if (whence == SEEK_SET)
target = offset;
else {
if (__libc_fstat(fp->_file, &st))
goto dumb;
target = st.st_size + offset;
}
if (!havepos) {
if (fp->_flags & __SOFF)
curoff = fp->_offset;
else {
curoff = (*seekfn)(fp->_cookie, (fpos_t)0, SEEK_CUR);
if (curoff == POS_ERR)
goto dumb;
}
curoff -= fp->_r;
if (HASUB(fp))
curoff -= fp->_ur;
}
/*
* Compute the number of bytes in the input buffer (pretending
* that any ungetc() input has been discarded). Adjust current
* offset backwards by this count so that it represents the
* file offset for the first byte in the current input buffer.
*/
if (HASUB(fp)) {
curoff += fp->_r; /* kill off ungetc */
n = fp->_up - fp->_bf._base;
curoff -= n;
n += fp->_ur;
} else {
n = fp->_p - fp->_bf._base;
curoff -= n;
n += fp->_r;
}
/*
* If the target offset is within the current buffer,
* simply adjust the pointers, clear EOF, undo ungetc(),
* and return. (If the buffer was modified, we have to
* skip this; see fgetln.c.)
*/
if ((fp->_flags & __SMOD) == 0 &&
target >= curoff && target < curoff + n) {
int o = target - curoff;
fp->_p = fp->_bf._base + o;
fp->_r = n - o;
if (HASUB(fp))
FREEUB(fp);
fp->_flags &= ~__SEOF;
FUNLOCKFILE(fp);
return (0);
}
/*
* The place we want to get to is not within the current buffer,
* but we can still be kind to the kernel copyout mechanism.
* By aligning the file offset to a block boundary, we can let
* the kernel use the VM hardware to map pages instead of
* copying bytes laboriously. Using a block boundary also
* ensures that we only read one block, rather than two.
*/
curoff = target & ~(fp->_blksize - 1);
if ((*seekfn)(fp->_cookie, curoff, SEEK_SET) == POS_ERR)
goto dumb;
fp->_r = 0;
fp->_p = fp->_bf._base;
if (HASUB(fp))
FREEUB(fp);
fp->_flags &= ~__SEOF;
n = target - curoff;
if (n) {
if (__srefill(fp) || fp->_r < n)
goto dumb;
fp->_p += n;
fp->_r -= n;
}
FUNLOCKFILE(fp);
return (0);
/*
* We get here if we cannot optimise the seek ... just
* do it. Allow the seek function to change fp->_bf._base.
*/
dumb:
if (__sflush(fp) ||
(*seekfn)(fp->_cookie, (fpos_t)offset, whence) == POS_ERR) {
FUNLOCKFILE(fp);
return (EOF);
}
/* success: clear EOF indicator and discard ungetc() data */
if (HASUB(fp))
FREEUB(fp);
fp->_p = fp->_bf._base;
fp->_r = 0;
/* fp->_w = 0; */ /* unnecessary (I think...) */
fp->_flags &= ~__SEOF;
FUNLOCKFILE(fp);
return (0);
}
/*
* Refill a stdio buffer.
* Return EOF on eof or error, 0 otherwise.
*/
int
__srefill(FILE *fp)
{
_DIAGASSERT(fp != NULL);
if(fp == NULL) {
errno = EINVAL;
return (EOF);
}
/* make sure stdio is set up */
if (!__sdidinit)
__sinit();
fp->_r = 0; /* largely a convenience for callers */
/* SysV does not make this test; take it out for compatibility */
if (fp->_flags & __SEOF) {
return (EOF);
}
/* if not already reading, have to be reading and writing */
if ((fp->_flags & __SRD) == 0) {
if ((fp->_flags & __SRW) == 0) {
errno = EBADF;
fp->_flags |= __SERR; //<dvm> Allows differentiation between errors and EOF
return (EOF);
}
/* switch to reading */
if (fp->_flags & __SWR) {
if (__sflush(fp)) {
return (EOF);
}
fp->_flags &= ~__SWR;
fp->_w = 0;
fp->_lbfsize = 0;
}
fp->_flags |= __SRD;
} else {
/*
* We were reading. If there is an ungetc buffer,
* we must have been reading from that. Drop it,
* restoring the previous buffer (if any). If there
* is anything in that buffer, return.
*/
if (HASUB(fp)) {
FREEUB(fp);
if ((fp->_r = fp->_ur) != 0) {
fp->_p = fp->_up;
return (0);
}
}
}
if (fp->_bf._base == NULL)
__smakebuf(fp);
/*
* Before reading from a line buffered or unbuffered file,
* flush all line buffered output files, per the ANSI C
* standard.
*/
if (fp->_flags & (__SLBF|__SNBF)) {
rwlock_rdlock(&__sfp_lock);
(void) _fwalk(lflush);
rwlock_unlock(&__sfp_lock);
}
fp->_p = fp->_bf._base;
fp->_r = (*fp->_read)(fp->_cookie, (char *)fp->_p, fp->_bf._size);
fp->_flags &= ~__SMOD; /* buffer contents are again pristine */
if (fp->_r <= 0) {
if (fp->_r == 0)
fp->_flags |= __SEOF;
else {
fp->_r = 0;
fp->_flags |= __SERR;
}
return (EOF);
}
return (0);
}
/*
* Seek the given file to the given offset.
* `Whence' must be one of the three SEEK_* macros.
*/
int
_fseeko(FILE *fp, off_t offset, int whence, int ltest)
{
fpos_t (*seekfn)(void *, fpos_t, int);
fpos_t target, curoff, ret;
size_t n;
struct stat st;
int havepos;
/*
* Have to be able to seek.
*/
if ((seekfn = fp->_seek) == NULL) {
errno = ESPIPE; /* historic practice */
return (-1);
}
/*
* Change any SEEK_CUR to SEEK_SET, and check `whence' argument.
* After this, whence is either SEEK_SET or SEEK_END.
*/
switch (whence) {
case SEEK_CUR:
/*
* In order to seek relative to the current stream offset,
* we have to first find the current stream offset via
* ftell (see ftell for details).
*/
if (_ftello(fp, &curoff))
return (-1);
if (curoff < 0) {
/* Unspecified position because of ungetc() at 0 */
errno = ESPIPE;
return (-1);
}
if (offset > 0 && curoff > OFF_MAX - offset) {
errno = EOVERFLOW;
return (-1);
}
offset += curoff;
if (offset < 0) {
errno = EINVAL;
return (-1);
}
if (ltest && offset > LONG_MAX) {
errno = EOVERFLOW;
return (-1);
}
whence = SEEK_SET;
havepos = 1;
break;
case SEEK_SET:
if (offset < 0) {
errno = EINVAL;
return (-1);
}
case SEEK_END:
curoff = 0; /* XXX just to keep gcc quiet */
havepos = 0;
break;
default:
errno = EINVAL;
return (-1);
}
/*
* Can only optimise if:
* reading (and not reading-and-writing);
* not unbuffered; and
* this is a `regular' Unix file (and hence seekfn==__sseek).
* We must check __NBF first, because it is possible to have __NBF
* and __SOPT both set.
*/
if (fp->_bf._base == NULL)
__smakebuf(fp);
if (fp->pub._flags & (__SWR | __SRW | __SNBF | __SNPT))
goto dumb;
if ((fp->pub._flags & __SOPT) == 0) {
if (seekfn != __sseek ||
fp->pub._fileno < 0 || _fstat(fp->pub._fileno, &st) ||
(st.st_mode & S_IFMT) != S_IFREG) {
fp->pub._flags |= __SNPT;
goto dumb;
}
fp->_blksize = st.st_blksize;
fp->pub._flags |= __SOPT;
}
/*
* We are reading; we can try to optimise.
* Figure out where we are going and where we are now.
*/
if (whence == SEEK_SET)
target = offset;
else {
if (_fstat(fp->pub._fileno, &st))
goto dumb;
if (offset > 0 && st.st_size > OFF_MAX - offset) {
errno = EOVERFLOW;
return (-1);
}
target = st.st_size + offset;
if ((off_t)target < 0) {
errno = EINVAL;
return (-1);
}
if (ltest && (off_t)target > LONG_MAX) {
errno = EOVERFLOW;
return (-1);
}
}
if (!havepos && _ftello(fp, &curoff))
goto dumb;
/*
* (If the buffer was modified, we have to
* skip this; see fgetln.c.)
*/
if (fp->pub._flags & __SMOD)
goto abspos;
/*
* Compute the number of bytes in the input buffer (pretending
* that any ungetc() input has been discarded). Adjust current
* offset backwards by this count so that it represents the
* file offset for the first byte in the current input buffer.
*/
if (HASUB(fp)) {
curoff += fp->pub._r; /* kill off ungetc */
n = fp->_up - fp->_bf._base;
curoff -= n;
n += fp->_ur;
} else {
n = fp->pub._p - fp->_bf._base;
curoff -= n;
n += fp->pub._r;
}
/*
* If the target offset is within the current buffer,
* simply adjust the pointers, clear EOF, undo ungetc(),
* and return.
*/
if (target >= curoff && target < curoff + n) {
size_t o = target - curoff;
fp->pub._p = fp->_bf._base + o;
fp->pub._r = n - o;
if (HASUB(fp))
FREEUB(fp);
fp->pub._flags &= ~__SEOF;
memset(WCIO_GET(fp), 0, sizeof(struct wchar_io_data));
return (0);
}
abspos:
/*
* The place we want to get to is not within the current buffer,
* but we can still be kind to the kernel copyout mechanism.
* By aligning the file offset to a block boundary, we can let
* the kernel use the VM hardware to map pages instead of
* copying bytes laboriously. Using a block boundary also
* ensures that we only read one block, rather than two.
*/
curoff = target & ~(fp->_blksize - 1);
if (_sseek(fp, curoff, SEEK_SET) == POS_ERR)
goto dumb;
fp->pub._r = 0;
fp->pub._p = fp->_bf._base;
if (HASUB(fp))
FREEUB(fp);
n = target - curoff;
if (n) {
if (__srefill(fp) || fp->pub._r < n)
goto dumb;
fp->pub._p += n;
fp->pub._r -= n;
}
fp->pub._flags &= ~__SEOF;
memset(WCIO_GET(fp), 0, sizeof(struct wchar_io_data));
return (0);
/*
* We get here if we cannot optimise the seek ... just
* do it. Allow the seek function to change fp->_bf._base.
*/
dumb:
if (__sflush(fp) ||
(ret = _sseek(fp, (fpos_t)offset, whence)) == POS_ERR)
return (-1);
if (ltest && ret > LONG_MAX) {
fp->pub._flags |= __SERR;
errno = EOVERFLOW;
return (-1);
}
/* success: clear EOF indicator and discard ungetc() data */
if (HASUB(fp))
FREEUB(fp);
fp->pub._p = fp->_bf._base;
fp->pub._r = 0;
/* fp->pub._w = 0; */ /* unnecessary (I think...) */
fp->pub._flags &= ~__SEOF;
memset(WCIO_GET(fp), 0, sizeof(struct wchar_io_data));
return (0);
}
/*
* Refill a stdio buffer.
* Return EOF on eof or error, 0 otherwise.
*/
int
__srefill(FILE *fp)
{
/* make sure stdio is set up */
if (!__sdidinit)
__sinit();
ORIENT(fp, -1);
fp->_r = 0; /* largely a convenience for callers */
/* SysV does not make this test; take it out for compatibility */
if (fp->_flags & __SEOF)
return (EOF);
/* if not already reading, have to be reading and writing */
if ((fp->_flags & __SRD) == 0) {
if ((fp->_flags & __SRW) == 0) {
errno = EBADF;
fp->_flags |= __SERR;
return (EOF);
}
/* switch to reading */
if (fp->_flags & __SWR) {
if (__sflush(fp))
return (EOF);
fp->_flags &= ~__SWR;
fp->_w = 0;
fp->_lbfsize = 0;
}
fp->_flags |= __SRD;
} else {
/*
* We were reading. If there is an ungetc buffer,
* we must have been reading from that. Drop it,
* restoring the previous buffer (if any). If there
* is anything in that buffer, return.
*/
if (HASUB(fp)) {
FREEUB(fp);
if ((fp->_r = fp->_ur) != 0) {
fp->_p = fp->_up;
return (0);
}
}
}
if (fp->_bf._base == NULL)
__smakebuf(fp);
/*
* Before reading from a line buffered or unbuffered file,
* flush all line buffered output files, per the ANSI C
* standard.
*/
if (fp->_flags & (__SLBF|__SNBF)) {
/* Ignore this file in _fwalk to avoid potential deadlock. */
fp->_flags |= __SIGN;
(void) _fwalk(lflush);
fp->_flags &= ~__SIGN;
/* Now flush this file without locking it. */
if ((fp->_flags & (__SLBF|__SWR)) == (__SLBF|__SWR))
__sflush(fp);
}
fp->_p = fp->_bf._base;
fp->_r = _sread(fp, (char *)fp->_p, fp->_bf._size);
fp->_flags &= ~__SMOD; /* buffer contents are again pristine */
if (fp->_r <= 0) {
if (fp->_r == 0)
fp->_flags |= __SEOF;
else {
fp->_r = 0;
fp->_flags |= __SERR;
}
return (EOF);
}
return (0);
}
int
__srefill (register FILE * fp)
{
/* make sure stdio is set up */
CHECK_INIT (fp);
fp->_r = 0; /* largely a convenience for callers */
/* SysV does not make this test; take it out for compatibility */
if (fp->_flags & __SEOF)
return EOF;
/* if not already reading, have to be reading and writing */
if ((fp->_flags & __SRD) == 0)
{
if ((fp->_flags & __SRW) == 0)
return EOF;
/* switch to reading */
if (fp->_flags & __SWR)
{
if (fflush (fp))
return EOF;
fp->_flags &= ~__SWR;
fp->_w = 0;
fp->_lbfsize = 0;
}
fp->_flags |= __SRD;
}
else
{
/*
* We were reading. If there is an ungetc buffer,
* we must have been reading from that. Drop it,
* restoring the previous buffer (if any). If there
* is anything in that buffer, return.
*/
if (HASUB (fp))
{
FREEUB (fp);
if ((fp->_r = fp->_ur) != 0)
{
fp->_p = fp->_up;
return 0;
}
}
}
if (fp->_bf._base == NULL)
__smakebuf (fp);
/*
* Before reading from a line buffered or unbuffered file,
* flush all line buffered output files, per the ANSI C
* standard.
*/
if (fp->_flags & (__SLBF | __SNBF))
(void) _fwalk (fp->_data, lflush);
fp->_p = fp->_bf._base;
fp->_r = (*fp->_read) (fp->_cookie, (char *) fp->_p, fp->_bf._size);
fp->_flags &= ~__SMOD; /* buffer contents are again pristine */
if (fp->_r <= 0)
{
if (fp->_r == 0)
fp->_flags |= __SEOF;
else
{
fp->_r = 0;
fp->_flags |= __SERR;
}
return EOF;
}
return 0;
}
int fseek
(
FAST FILE * fp, /* stream */
long offset, /* offset from <whence> */
int whence /* position to offset from: */
/* SEEK_SET = beginning */
/* SEEK_CUR = current position */
/* SEEK_END = end-of-file */
)
{
fpos_t target;
fpos_t curoff;
size_t n;
struct stat st;
int havepos;
BOOL doStat;
if (OBJ_VERIFY (fp, fpClassId) != OK)
return (ERROR);
/*
* Change any SEEK_CUR to SEEK_SET, and check `whence' argument.
* After this, whence is either SEEK_SET or SEEK_END.
*/
switch (whence)
{
case SEEK_CUR:
/*
* In order to seek relative to the current stream offset,
* we have to first find the current stream offset a la
* ftell (see ftell for details).
*/
if (fp->_flags & __SOFF)
curoff = fp->_offset;
else
{
curoff = __sseek (fp, (fpos_t)0, SEEK_CUR);
if (curoff == -1L)
return (EOF);
}
if (fp->_flags & __SRD)
{
curoff -= fp->_r;
if (HASUB(fp))
curoff -= fp->_ur;
}
else if (fp->_flags & __SWR && fp->_p != NULL)
curoff += fp->_p - fp->_bf._base;
offset += curoff;
whence = SEEK_SET;
havepos = 1;
break;
case SEEK_SET:
case SEEK_END:
curoff = 0; /* XXX just to keep gcc quiet */
havepos = 0;
break;
default:
errno = EINVAL;
return (EOF);
}
/*
* Can only optimise if:
* reading (and not reading-and-writing);
* not unbuffered; and
* this is a `regular' Unix file (and hence seekfn==__sseek).
* We must check __NBF first, because it is possible to have __NBF
* and __SOPT both set.
*/
if (fp->_bf._base == NULL)
__smakebuf (fp);
if (fp->_flags & (__SWR | __SRW | __SNBF | __SNPT))
goto dumb;
doStat = ioctl (fp->_file, FIOFSTATGET, (int)&st);
if ((fp->_flags & __SOPT) == 0)
{
if ((fp->_file < 0 || (doStat) ||
(st.st_mode & S_IFMT) != S_IFREG))
{
fp->_flags |= __SNPT;
goto dumb;
}
fp->_blksize = st.st_blksize;
fp->_flags |= __SOPT;
}
/*
* We are reading; we can try to optimise.
* Figure out where we are going and where we are now.
*/
if (whence == SEEK_SET)
target = offset;
else
{
if (doStat)
goto dumb;
target = st.st_size + offset;
}
if (!havepos)
{
if (fp->_flags & __SOFF)
curoff = fp->_offset;
else
{
curoff = __sseek (fp, 0L, SEEK_CUR);
if (curoff == POS_ERR)
goto dumb;
}
curoff -= fp->_r;
if (HASUB(fp))
curoff -= fp->_ur;
}
/*
* Compute the number of bytes in the input buffer (pretending
* that any ungetc() input has been discarded). Adjust current
* offset backwards by this count so that it represents the
* file offset for the first byte in the current input buffer.
*/
if (HASUB(fp))
{
n = fp->_up - fp->_bf._base;
curoff -= n;
n += fp->_ur;
}
else
{
n = fp->_p - fp->_bf._base;
curoff -= n;
n += fp->_r;
}
/*
* If the target offset is within the current buffer,
* simply adjust the pointers, clear EOF, undo ungetc(),
* and return. (If the buffer was modified, we have to
* skip this; see fgetline.c.)
*/
if (((fp->_flags & __SMOD) == 0) &&
(target >= curoff) &&
(target < (curoff + n)))
{
FAST int o = target - curoff;
fp->_p = fp->_bf._base + o;
fp->_r = n - o;
if (HASUB(fp))
FREEUB(fp);
fp->_flags &= ~__SEOF;
return (0);
}
/*
* The place we want to get to is not within the current buffer,
* but we can still be kind to the kernel copyout mechanism.
* By aligning the file offset to a block boundary, we can let
* the kernel use the VM hardware to map pages instead of
* copying bytes laboriously. Using a block boundary also
* ensures that we only read one block, rather than two.
*/
curoff = target & ~(fp->_blksize - 1);
if (__sseek (fp, curoff, SEEK_SET) == POS_ERR)
goto dumb;
fp->_r = 0;
if (HASUB(fp))
FREEUB(fp);
fp->_flags &= ~__SEOF;
n = target - curoff;
if (n)
{
if (__srefill (fp) || fp->_r < n)
goto dumb;
fp->_p += n;
fp->_r -= n;
}
return (0);
/*
* We get here if we cannot optimise the seek ... just
* do it. Allow the seek function to change fp->_bf._base.
*/
dumb:
if ((__sflush (fp)) || (__sseek (fp, offset, whence) == POS_ERR))
return (EOF);
/* success: clear EOF indicator and discard ungetc() data */
if (HASUB(fp))
FREEUB(fp);
fp->_p = fp->_bf._base;
fp->_r = 0;
/* fp->_w = 0; */ /* unnecessary (I think...) */
fp->_flags &= ~__SEOF;
return (0);
}
