init.c

openBSD UNIX sort命令实现完整源代码

/*	$OpenBSD: init.c,v 1.8 2005/04/11 07:12:03 deraadt Exp $	*/

/*-
 * Copyright (c) 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Peter McIlroy.
 *
 * 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.
 */

#ifndef lint
#if 0
static char sccsid[] = "@(#)init.c	8.1 (Berkeley) 6/6/93";
#else
static char rcsid[] = "$OpenBSD: init.c,v 1.8 2005/04/11 07:12:03 deraadt Exp $";
#endif
#endif /* not lint */

#include "sort.h"

#include <ctype.h>
#include <string.h>

extern struct coldesc *clist;
extern int ncols;
u_char gweights[NBINS];

static void insertcol(struct field *);
char *setcolumn(char *, struct field *, int);

/*
 * clist (list of columns which correspond to one or more icol or tcol)
 * is in increasing order of columns.
 * Fields are kept in increasing order of fields.
 */

/* 
 * keep clist in order--inserts a column in a sorted array
 */
static void
insertcol(struct field *field)
{
	int i;
	for (i = 0; i < ncols; i++)
		if (field->icol.num <= clist[i].num)
			break;
	if (field->icol.num != clist[i].num) {
		memmove(clist+i+1, clist+i, sizeof(COLDESC)*(ncols-i));
		clist[i].num = field->icol.num;
		ncols++;
	}
	if (field->tcol.num && field->tcol.num != field->icol.num) {
		for (i = 0; i < ncols; i++)
			if (field->tcol.num <= clist[i].num)
				break;
		if (field->tcol.num != clist[i].num) {
			memmove(clist+i+1, clist+i,sizeof(COLDESC)*(ncols-i));
			clist[i].num = field->tcol.num;
			ncols++;
		}
	}
}

/*
 * matches fields with the appropriate columns--n^2 but who cares?
 */
void
fldreset(struct field *fldtab)
{
	int i;
	fldtab[0].tcol.p = clist+ncols-1;
	for (++fldtab; fldtab->icol.num; ++fldtab) {
		for (i = 0; fldtab->icol.num != clist[i].num; i++)
			;
		fldtab->icol.p = clist + i;
		if (!fldtab->tcol.num)
			continue;
		for (i = 0; fldtab->tcol.num != clist[i].num; i++)
			;
		fldtab->tcol.p = clist + i;
	}
}

/*
 * interprets a column in a -k field
 */
char *
setcolumn(char *pos, struct field *cur_fld, int gflag)
{
	struct column *col;
	int tmp;

	col = cur_fld->icol.num ? (&(*cur_fld).tcol) : (&(*cur_fld).icol);
	pos += sscanf(pos, "%d", &(col->num));
	while (isdigit(*pos))
		pos++;
	if (col->num <= 0 && !(col->num == 0 && col == &(cur_fld->tcol)))
		errx(2, "field numbers must be positive");
	if (*pos == '.') {
		if (!col->num)
			errx(2, "cannot indent end of line");
		pos += sscanf(++pos, "%d", &(col->indent));
		while (isdigit(*pos))
			pos++;
		if (&cur_fld->icol == col)
			col->indent--;
		if (col->indent < 0)
			errx(2, "illegal offset");
	}
	if (optval(*pos, cur_fld->tcol.num))	
		while ((tmp = optval(*pos, cur_fld->tcol.num))) {
			cur_fld->flags |= tmp;
			pos++;
	}
	if (cur_fld->icol.num == 0)
		cur_fld->icol.num = 1;
	return (pos);
}

int
setfield(char *pos, struct field *cur_fld, int gflag)
{
	int tmp;
	cur_fld->weights = ascii;
	cur_fld->mask = alltable;
	pos = setcolumn(pos, cur_fld, gflag);
	if (*pos == '\0')			/* key extends to EOL. */
		cur_fld->tcol.num = 0;
	else {
		if (*pos != ',')
			errx(2, "illegal field descriptor");
		setcolumn((++pos), cur_fld, gflag);
	}
	if (!cur_fld->flags)
		cur_fld->flags = gflag;
	tmp = cur_fld->flags;

	/*
	 * Assign appropriate mask table and weight table.
	 * If the global weights are reversed, the local field
	 * must be "re-reversed".
	 */
	if (((tmp & R) ^ (gflag & R)) && tmp & F)
		cur_fld->weights = RFtable;
	else if (tmp & F)
		cur_fld->weights = Ftable;
	else if ((tmp & R) ^ (gflag & R))
		cur_fld->weights = Rascii;
	if (tmp & I)
		cur_fld->mask = itable;
	else if (tmp & D)
		cur_fld->mask = dtable;
	cur_fld->flags |= (gflag & (BI | BT));
	if (!cur_fld->tcol.indent)	/* BT has no meaning at end of field */
		cur_fld->flags &= (D|F|I|N|R|BI);
	if (cur_fld->tcol.num && !(!(cur_fld->flags & BI)
	    && cur_fld->flags & BT) && (cur_fld->tcol.num <= cur_fld->icol.num
	    && cur_fld->tcol.indent < cur_fld->icol.indent))
		errx(2, "fields out of order");
	insertcol(cur_fld);
	return (cur_fld->tcol.num);
}

int
optval(int desc, int tcolflag)
{
	switch(desc) {
		case 'b':
			if (!tcolflag)
				return (BI);
			else
				return (BT);
		case 'd': return (D);
		case 'f': return (F);
		case 'i': return (I);
		case 'n': return (N);
		case 'r': return (R);
		default:  return (0);
	}
}

/*
 * Convert obsolescent "+pos1 [-pos2]" format to POSIX -k form.
 * Note that the conversion is tricky, see the manual for details.
 */
void
fixit(int *argc, char **argv)
{
	int i, j;
	long v, w, x;
	char *p, *ep;
	char buf[128], *bufp, *bufend;
	size_t n;

	bufend = buf + sizeof(buf);
	for (i = 1; i < *argc; i++) {
		if (argv[i][0] == '+') {
			bufp = buf;
			p = argv[i] + 1;
			v = strtol(p, &ep, 10);
			if (ep == p || v < 0 ||
			    (v == LONG_MAX && errno == ERANGE))
				errx(2, "invalid field number");
			p = ep;
			if (*p == '.') {
				x = strtol(++p, &ep, 10);
				if (ep == p || x < 0 ||
				    (x == LONG_MAX && errno == ERANGE))
					errx(2, "invalid field number");
				p = ep;
				n = snprintf(bufp, bufend - bufp, "-k%ld.%ld%s",
				    v+1, x+1, p);
			} else {
				n = snprintf(bufp, bufend - bufp, "-k%ld%s",
				    v+1, p);
			}
			if (n == -1 || n >= bufend - bufp)
				errx(2, "bad field specification");
			bufp += n;

			if (argv[i+1] &&
			    argv[i+1][0] == '-' && isdigit(argv[i+1][1])) {
				p = argv[i+1] + 1;
				w = strtol(p, &ep, 10);
				if (ep == p || w < 0 ||
				    (w == LONG_MAX && errno == ERANGE))
					errx(2, "invalid field number");
				p = ep;
				x = 0;
				if (*p == '.') {
					x = strtol(++p, &ep, 10);
					if (ep == p || x < 0 ||
					    (x == LONG_MAX && errno == ERANGE))
						errx(2, "invalid field number");
					p = ep;
				}
				if (x == 0) {
					n = snprintf(bufp, bufend - bufp,
					    ",%ld%s", w, p);
				} else {
					n = snprintf(bufp, bufend - bufp,
					    ",%ld.%ld%s", w+1, x, p);
				}
				if (n == -1 || n >= bufend - bufp)
					errx(2, "bad field specification");

				/* shift over argv */
				for (j = i+1; j < *argc; j++)
					argv[j] = argv[j+1];
				*argc -= 1;
			}
			if ((argv[i] = strdup(buf)) == NULL)
				err(2, NULL);
		}
	}
}

/*
 * ascii, Rascii, Ftable, and RFtable map
 * REC_D -> REC_D;  {not REC_D} -> {not REC_D}.
 * gweights maps REC_D -> (0 or 255); {not REC_D} -> {not gweights[REC_D]}.
 * Note: when sorting in forward order, to encode character zero in a key,
 * use \001\001; character 1 becomes \001\002.  In this case, character 0
 * is reserved for the field delimiter.  Analagously for -r (fld_d = 255).
 * Note: this is only good for ASCII sorting.  For different LC 's,
 * all bets are off.  See also num_init in number.c
 */
void
settables(int gflags)
{
	u_char *wts;
	int i, incr;
	for (i=0; i < 256; i++) {
		ascii[i] = i;
		if (i > REC_D && i < 255 - REC_D+1)
			Rascii[i] = 255 - i + 1;
		else
			Rascii[i] = 255 - i;
		if (islower(i)) {
			Ftable[i] = Ftable[i- ('a' -'A')];
			RFtable[i] = RFtable[i - ('a' - 'A')];
		} else if (REC_D>= 'A' && REC_D < 'Z' && i < 'a' && i > REC_D) {
			Ftable[i] = i + 1;
			RFtable[i] = Rascii[i] - 1;
		} else {
			Ftable[i] = i;
			RFtable[i] = Rascii[i];
		}
		alltable[i] = 1;
		if (i == '\n' || isprint(i))
			itable[i] = 1;
		else itable[i] = 0;
		if (i == '\n' || i == '\t' || i == ' ' || isalnum(i))
			dtable[i] = 1;
		else dtable[i] = 0;
	}
	Rascii[REC_D] = RFtable[REC_D] = REC_D;
	if (REC_D >= 'A' && REC_D < 'Z')
		Ftable[REC_D + ('a' - 'A')]++;
	if (gflags & R && (!(gflags & F) || !SINGL_FLD))
		wts = Rascii;
	else if (!(gflags & F) || !SINGL_FLD)
		wts = ascii;
	else if (gflags & R)
		wts = RFtable;
	else
		wts = Ftable;
	memmove(gweights, wts, sizeof(gweights));
	incr = (gflags & R) ? -1 : 1;
	for (i = 0; i < REC_D; i++)
		gweights[i] += incr;
	gweights[REC_D] = ((gflags & R) ? 255 : 0);
	if (SINGL_FLD && gflags & F) {
		for (i = 0; i < REC_D; i++) {
			ascii[i] += incr;
			Rascii[i] += incr;
		}
		ascii[REC_D] = Rascii[REC_D] = gweights[REC_D];
	}
}