/*
* Helper function for `fprintf to unbuffered unix file': creates a
* temporary buffer. We only work on write-only files; this avoids
* worries about ungetc buffers and so forth.
*/
static int
__sbprintf(FILE *fp, const char *fmt, va_list ap)
{
int ret;
FILE fake = FAKE_FILE;
unsigned char buf[BUFSIZ];
/* XXX This is probably not needed. */
if (prepwrite(fp) != 0)
return (EOF);
/* copy the important variables */
fake._flags = fp->_flags & ~__SNBF;
fake._file = fp->_file;
fake._cookie = fp->_cookie;
fake._write = fp->_write;
fake._orientation = fp->_orientation;
fake._mbstate = fp->_mbstate;
/* set up the buffer */
fake._bf._base = fake._p = buf;
fake._bf._size = fake._w = sizeof(buf);
fake._lbfsize = 0; /* not actually used, but Just In Case */
/* do the work, then copy any error status */
ret = __vfprintf(&fake, fmt, ap);
if (ret >= 0 && __fflush(&fake))
ret = EOF;
if (fake._flags & __SERR)
fp->_flags |= __SERR;
return (ret);
}
/*
* Write some memory regions. Return zero on success, EOF on error.
*
* This routine is large and unsightly, but most of the ugliness due
* to the three different kinds of output buffering is handled here.
*/
int
__sfvwrite(FILE *fp, struct __suio *uio)
{
size_t len;
char *p;
struct __siov *iov;
int w, s;
char *nl;
int nlknown, nldist;
if ((len = uio->uio_resid) == 0)
return (0);
/* make sure we can write */
if (prepwrite(fp) != 0)
return (EOF);
#define MIN(a, b) ((a) < (b) ? (a) : (b))
#define COPY(n) memcpy((void *)fp->pub._p, (void *)p, (size_t)(n))
iov = uio->uio_iov;
p = iov->iov_base;
len = iov->iov_len;
iov++;
#define GETIOV(extra_work) \
while (len == 0) { \
extra_work; \
p = iov->iov_base; \
len = iov->iov_len; \
iov++; \
}
if (fp->pub._flags & __SNBF) {
/*
* Unbuffered: write up to BUFSIZ bytes at a time.
*/
do {
GETIOV(;);
w = _swrite(fp, p, MIN(len, BUFSIZ));
if (w <= 0)
goto err;
p += w;
len -= w;
} while ((uio->uio_resid -= w) != 0);
} else if ((fp->pub._flags & __SLBF) == 0) {
/*
* Write the given character into the (probably full) buffer for
* the given file. Flush the buffer out if it is or becomes full,
* or if c=='\n' and the file is line buffered.
*
* Non-MT-safe
*/
int
__swbuf(int c, FILE *fp)
{
int n;
/*
* In case we cannot write, or longjmp takes us out early,
* make sure _w is 0 (if fully- or un-buffered) or -_bf._size
* (if line buffered) so that we will get called again.
* If we did not do this, a sufficient number of putc()
* calls might wrap _w from negative to positive.
*/
fp->_w = fp->_lbfsize;
if (prepwrite(fp) != 0)
return (EOF);
c = (unsigned char)c;
ORIENT(fp, -1);
/*
* If it is completely full, flush it out. Then, in any case,
* stuff c into the buffer. If this causes the buffer to fill
* completely, or if c is '\n' and the file is line buffered,
* flush it (perhaps a second time). The second flush will always
* happen on unbuffered streams, where _bf._size==1; fflush()
* guarantees that putc() will always call wbuf() by setting _w
* to 0, so we need not do anything else.
*/
n = fp->_p - fp->_bf._base;
if (n >= fp->_bf._size) {
if (__fflush(fp))
return (EOF);
n = 0;
}
fp->_w--;
*fp->_p++ = c;
if (++n == fp->_bf._size || (fp->_flags & __SLBF && c == '\n'))
if (__fflush(fp))
return (EOF);
return (c);
}
