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-rw-r--r--usr.bin/tail/reverse.c259
1 files changed, 0 insertions, 259 deletions
diff --git a/usr.bin/tail/reverse.c b/usr.bin/tail/reverse.c
deleted file mode 100644
index 34cd980..0000000
--- a/usr.bin/tail/reverse.c
+++ /dev/null
@@ -1,259 +0,0 @@
-/*-
- * Copyright (c) 1991, 1993
- * The Regents of the University of California. All rights reserved.
- *
- * This code is derived from software contributed to Berkeley by
- * Edward Sze-Tyan Wang.
- *
- * 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. All advertising materials mentioning features or use of this software
- * must display the following acknowledgement:
- * This product includes software developed by the University of
- * California, Berkeley and its contributors.
- * 4. 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.
- */
-
-#ifndef lint
-static char sccsid[] = "@(#)reverse.c 8.1 (Berkeley) 6/6/93";
-#endif /* not lint */
-
-#include <sys/param.h>
-#include <sys/stat.h>
-#include <sys/mman.h>
-
-#include <limits.h>
-#include <errno.h>
-#include <unistd.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include "extern.h"
-
-static void r_buf __P((FILE *));
-static void r_reg __P((FILE *, enum STYLE, long, struct stat *));
-
-/*
- * reverse -- display input in reverse order by line.
- *
- * There are six separate cases for this -- regular and non-regular
- * files by bytes, lines or the whole file.
- *
- * BYTES display N bytes
- * REG mmap the file and display the lines
- * NOREG cyclically read characters into a wrap-around buffer
- *
- * LINES display N lines
- * REG mmap the file and display the lines
- * NOREG cyclically read lines into a wrap-around array of buffers
- *
- * FILE display the entire file
- * REG mmap the file and display the lines
- * NOREG cyclically read input into a linked list of buffers
- */
-void
-reverse(fp, style, off, sbp)
- FILE *fp;
- enum STYLE style;
- long off;
- struct stat *sbp;
-{
- if (style != REVERSE && off == 0)
- return;
-
- if (S_ISREG(sbp->st_mode))
- r_reg(fp, style, off, sbp);
- else
- switch(style) {
- case FBYTES:
- case RBYTES:
- bytes(fp, off);
- break;
- case FLINES:
- case RLINES:
- lines(fp, off);
- break;
- case REVERSE:
- r_buf(fp);
- break;
- }
-}
-
-/*
- * r_reg -- display a regular file in reverse order by line.
- */
-static void
-r_reg(fp, style, off, sbp)
- FILE *fp;
- register enum STYLE style;
- long off;
- struct stat *sbp;
-{
- register off_t size;
- register int llen;
- register char *p;
- char *start;
-
- if (!(size = sbp->st_size))
- return;
-
- if (size > SIZE_T_MAX) {
- err(0, "%s: %s", fname, strerror(EFBIG));
- return;
- }
-
- if ((start = mmap(NULL, (size_t)size,
- PROT_READ, 0, fileno(fp), (off_t)0)) == (caddr_t)-1) {
- err(0, "%s: %s", fname, strerror(EFBIG));
- return;
- }
- p = start + size - 1;
-
- if (style == RBYTES && off < size)
- size = off;
-
- /* Last char is special, ignore whether newline or not. */
- for (llen = 1; --size; ++llen)
- if (*--p == '\n') {
- WR(p + 1, llen);
- llen = 0;
- if (style == RLINES && !--off) {
- ++p;
- break;
- }
- }
- if (llen)
- WR(p, llen);
- if (munmap(start, (size_t)sbp->st_size))
- err(0, "%s: %s", fname, strerror(errno));
-}
-
-typedef struct bf {
- struct bf *next;
- struct bf *prev;
- int len;
- char *l;
-} BF;
-
-/*
- * r_buf -- display a non-regular file in reverse order by line.
- *
- * This is the function that saves the entire input, storing the data in a
- * doubly linked list of buffers and then displays them in reverse order.
- * It has the usual nastiness of trying to find the newlines, as there's no
- * guarantee that a newline occurs anywhere in the file, let alone in any
- * particular buffer. If we run out of memory, input is discarded (and the
- * user warned).
- */
-static void
-r_buf(fp)
- FILE *fp;
-{
- register BF *mark, *tl, *tr;
- register int ch, len, llen;
- register char *p;
- off_t enomem;
-
-#define BSZ (128 * 1024)
- for (mark = NULL, enomem = 0;;) {
- /*
- * Allocate a new block and link it into place in a doubly
- * linked list. If out of memory, toss the LRU block and
- * keep going.
- */
- if (enomem || (tl = malloc(sizeof(BF))) == NULL ||
- (tl->l = malloc(BSZ)) == NULL) {
- if (!mark)
- err(1, "%s", strerror(errno));
- tl = enomem ? tl->next : mark;
- enomem += tl->len;
- } else if (mark) {
- tl->next = mark;
- tl->prev = mark->prev;
- mark->prev->next = tl;
- mark->prev = tl;
- } else
- mark->next = mark->prev = (mark = tl);
-
- /* Fill the block with input data. */
- for (p = tl->l, len = 0;
- len < BSZ && (ch = getc(fp)) != EOF; ++len)
- *p++ = ch;
-
- /*
- * If no input data for this block and we tossed some data,
- * recover it.
- */
- if (!len) {
- if (enomem)
- enomem -= tl->len;
- tl = tl->prev;
- break;
- }
-
- tl->len = len;
- if (ch == EOF)
- break;
- }
-
- if (enomem) {
- (void)fprintf(stderr,
- "tail: warning: %ld bytes discarded\n", enomem);
- rval = 1;
- }
-
- /*
- * Step through the blocks in the reverse order read. The last char
- * is special, ignore whether newline or not.
- */
- for (mark = tl;;) {
- for (p = tl->l + (len = tl->len) - 1, llen = 0; len--;
- --p, ++llen)
- if (*p == '\n') {
- if (llen) {
- WR(p + 1, llen);
- llen = 0;
- }
- if (tl == mark)
- continue;
- for (tr = tl->next; tr->len; tr = tr->next) {
- WR(tr->l, tr->len);
- tr->len = 0;
- if (tr == mark)
- break;
- }
- }
- tl->len = llen;
- if ((tl = tl->prev) == mark)
- break;
- }
- tl = tl->next;
- if (tl->len) {
- WR(tl->l, tl->len);
- tl->len = 0;
- }
- while ((tl = tl->next)->len) {
- WR(tl->l, tl->len);
- tl->len = 0;
- }
-}
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