diff options
Diffstat (limited to 'libc/stdio/ungetc.c')
| -rw-r--r-- | libc/stdio/ungetc.c | 141 |
1 files changed, 0 insertions, 141 deletions
diff --git a/libc/stdio/ungetc.c b/libc/stdio/ungetc.c deleted file mode 100644 index fe05258..0000000 --- a/libc/stdio/ungetc.c +++ /dev/null @@ -1,141 +0,0 @@ -/* $OpenBSD: ungetc.c,v 1.9 2005/08/08 08:05:36 espie Exp $ */ -/*- - * Copyright (c) 1990, 1993 - * The Regents of the University of California. All rights reserved. - * - * This code is derived from software contributed to Berkeley by - * Chris Torek. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * 3. Neither the name of the University nor the names of its contributors - * may be used to endorse or promote products derived from this software - * without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND - * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE - * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE - * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL - * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS - * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT - * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY - * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF - * SUCH DAMAGE. - */ - -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include "local.h" - -static int __submore(FILE *); -/* - * Expand the ungetc buffer `in place'. That is, adjust fp->_p when - * the buffer moves, so that it points the same distance from the end, - * and move the bytes in the buffer around as necessary so that they - * are all at the end (stack-style). - */ -static int -__submore(FILE *fp) -{ - int i; - unsigned char *p; - - if (_UB(fp)._base == fp->_ubuf) { - /* - * Get a new buffer (rather than expanding the old one). - */ - if ((p = malloc((size_t)BUFSIZ)) == NULL) - return (EOF); - _UB(fp)._base = p; - _UB(fp)._size = BUFSIZ; - p += BUFSIZ - sizeof(fp->_ubuf); - for (i = sizeof(fp->_ubuf); --i >= 0;) - p[i] = fp->_ubuf[i]; - fp->_p = p; - return (0); - } - i = _UB(fp)._size; - p = realloc(_UB(fp)._base, i << 1); - if (p == NULL) - return (EOF); - /* no overlap (hence can use memcpy) because we doubled the size */ - (void)memcpy((void *)(p + i), (void *)p, (size_t)i); - fp->_p = p + i; - _UB(fp)._base = p; - _UB(fp)._size = i << 1; - return (0); -} - -int -ungetc(int c, FILE *fp) -{ - if (c == EOF) - return (EOF); - if (!__sdidinit) - __sinit(); - _SET_ORIENTATION(fp, -1); - if ((fp->_flags & __SRD) == 0) { - /* - * Not already reading: no good unless reading-and-writing. - * Otherwise, flush any current write stuff. - */ - if ((fp->_flags & __SRW) == 0) - return (EOF); - if (fp->_flags & __SWR) { - if (__sflush(fp)) - return (EOF); - fp->_flags &= ~__SWR; - fp->_w = 0; - fp->_lbfsize = 0; - } - fp->_flags |= __SRD; - } - c = (unsigned char)c; - - /* - * If we are in the middle of ungetc'ing, just continue. - * This may require expanding the current ungetc buffer. - */ - if (HASUB(fp)) { - if (fp->_r >= _UB(fp)._size && __submore(fp)) - return (EOF); - *--fp->_p = c; - fp->_r++; - return (c); - } - fp->_flags &= ~__SEOF; - - /* - * If we can handle this by simply backing up, do so, - * but never replace the original character. - * (This makes sscanf() work when scanning `const' data.) - */ - if (fp->_bf._base != NULL && fp->_p > fp->_bf._base && - fp->_p[-1] == c) { - fp->_p--; - fp->_r++; - return (c); - } - - /* - * Create an ungetc buffer. - * Initially, we will use the `reserve' buffer. - */ - fp->_ur = fp->_r; - fp->_up = fp->_p; - _UB(fp)._base = fp->_ubuf; - _UB(fp)._size = sizeof(fp->_ubuf); - fp->_ubuf[sizeof(fp->_ubuf) - 1] = c; - fp->_p = &fp->_ubuf[sizeof(fp->_ubuf) - 1]; - fp->_r = 1; - return (c); -} |