pat_rep.c

早期freebsd实现

/*-
 * Copyright (c) 1992 Keith Muller.
 * Copyright (c) 1992, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Keith Muller of the University of California, San Diego.
 *
 * 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[] = "@(#)pat_rep.c	8.2 (Berkeley) 4/18/94";
#endif /* not lint */

#include <sys/types.h>
#include <sys/time.h>
#include <sys/stat.h>
#include <sys/param.h>
#include <stdio.h>
#include <ctype.h>
#include <string.h>
#include <unistd.h>
#include <stdlib.h>
#ifdef NET2_REGEX
#include <regexp.h>
#else
#include <regex.h>
#endif
#include "pax.h"
#include "pat_rep.h"
#include "extern.h"

/*
 * routines to handle pattern matching, name modification (regular expression
 * substitution and interactive renames), and destination name modification for
 * copy (-rw). Both file name and link names are adjusted as required in these
 * routines.
 */

#define MAXSUBEXP	10		/* max subexpressions, DO NOT CHANGE */
static PATTERN *pathead = NULL;		/* file pattern match list head */
static PATTERN *pattail = NULL;		/* file pattern match list tail */
static REPLACE *rephead = NULL;		/* replacement string list head */
static REPLACE *reptail = NULL;		/* replacement string list tail */

static int rep_name __P((char *, int *, int));
static int tty_rename __P((register ARCHD *));
static int fix_path __P((char *, int *, char *, int));
static int fn_match __P((register char *, register char *, char **));
static char * range_match __P((register char *, register int));
#ifdef NET2_REGEX
static int resub __P((regexp *, char *, char *, register char *));
#else
static int resub __P((regex_t *, regmatch_t *, char *, char *, char *));
#endif

/*
 * rep_add()
 *	parses the -s replacement string; compiles the regular expression
 *	and stores the compiled value and it's replacement string together in
 *	replacement string list. Input to this function is of the form:
 *		/old/new/pg 
 *	The first char in the string specifies the delimiter used by this
 *	replacement string. "Old" is a regular expression in "ed" format which
 *	is compiled by regcomp() and is applied to filenames. "new" is the
 *	substitution string; p and g are options flags for printing and global
 *	replacement (over the single filename)
 * Return:
 *	0 if a proper replacement string and regular expression was added to
 *	the list of replacement patterns; -1 otherwise.
 */

#if __STDC__
int
rep_add(register char *str)
#else
int
rep_add(str)
	register char *str;
#endif
{
	register char *pt1;
	register char *pt2;
	register REPLACE *rep;
#	ifndef NET2_REGEX
	register int res;
	char rebuf[BUFSIZ];
#	endif

	/*
	 * throw out the bad parameters
	 */
	if ((str == NULL) || (*str == '\0')) {
		warn(1, "Empty replacement string");
		return(-1);
	}

	/*
	 * first character in the string specifies what the delimiter is for
	 * this expression
	 */
	if ((pt1 = strchr(str+1, *str)) == NULL) {
		warn(1, "Invalid replacement string %s", str);
		return(-1);
	}

	/*
	 * allocate space for the node that handles this replacement pattern
	 * and split out the regular expression and try to compile it
	 */
	if ((rep = (REPLACE *)malloc(sizeof(REPLACE))) == NULL) {
		warn(1, "Unable to allocate memory for replacement string");
		return(-1);
	}

	*pt1 = '\0';
#	ifdef NET2_REGEX
	if ((rep->rcmp = regcomp(str+1)) == NULL) {
#	else
	if ((res = regcomp(&(rep->rcmp), str+1, 0)) != 0) {
		regerror(res, &(rep->rcmp), rebuf, sizeof(rebuf));
		warn(1, "%s while compiling regular expression %s", rebuf, str);
#	endif
		(void)free((char *)rep);
		return(-1);
	}

	/*
	 * put the delimiter back in case we need an error message and
	 * locate the delimiter at the end of the replacement string
	 * we then point the node at the new substitution string
	 */
	*pt1++ = *str;
	if ((pt2 = strchr(pt1, *str)) == NULL) {
#		ifdef NET2_REGEX
		(void)free((char *)rep->rcmp);
#		else
		regfree(&(rep->rcmp));
#		endif
		(void)free((char *)rep);
		warn(1, "Invalid replacement string %s", str);
		return(-1);
	}

	*pt2 = '\0';
	rep->nstr = pt1;
	pt1 = pt2++;
	rep->flgs = 0;

	/*
	 * set the options if any
	 */
	while (*pt2 != '\0') {
		switch(*pt2) {
		case 'g':
		case 'G':
			rep->flgs  |= GLOB;
			break;
		case 'p':
		case 'P':
			rep->flgs  |= PRNT;
			break;
		default:
#			ifdef NET2_REGEX
			(void)free((char *)rep->rcmp);
#			else
			regfree(&(rep->rcmp));
#			endif
			(void)free((char *)rep);
			*pt1 = *str;
			warn(1, "Invalid replacement string option %s", str);
			return(-1);
		}
		++pt2;
	}

	/*
	 * all done, link it in at the end
	 */
	rep->fow = NULL;
	if (rephead == NULL) {
		reptail = rephead = rep;
		return(0);
	}
	reptail->fow = rep;
	reptail = rep;
	return(0);
}

/*
 * pat_add()
 *	add a pattern match to the pattern match list. Pattern matches are used
 *	to select which archive members are extracted. (They appear as
 *	arguments to pax in the list and read modes). If no patterns are
 *	supplied to pax, all members in the archive will be selected (and the
 *	pattern match list is empty).
 * Return:
 *	0 if the pattern was added to the list, -1 otherwise
 */

#if __STDC__
int
pat_add(char *str)
#else
int
pat_add(str)
	char *str;
#endif
{
	register PATTERN *pt;

	/*
	 * throw out the junk
	 */
	if ((str == NULL) || (*str == '\0')) {
		warn(1, "Empty pattern string");
		return(-1);
	}

	/*
	 * allocate space for the pattern and store the pattern. the pattern is
	 * part of argv so do not bother to copy it, just point at it. Add the
	 * node to the end of the pattern list
	 */
	if ((pt = (PATTERN *)malloc(sizeof(PATTERN))) == NULL) {
		warn(1, "Unable to allocate memory for pattern string");
		return(-1);
	}

	pt->pstr = str;
	pt->pend = NULL;
	pt->plen = strlen(str);
	pt->fow = NULL;
	pt->flgs = 0;
	if (pathead == NULL) {
		pattail = pathead = pt;
		return(0);
	}
	pattail->fow = pt;
	pattail = pt;
	return(0);
}

/*
 * pat_chk()
 *	complain if any the user supplied pattern did not result in a match to
 *	a selected archive member.
 */

#if __STDC__
void
pat_chk(void)
#else
void
pat_chk()
#endif
{
	register PATTERN *pt;
	register int wban = 0;

	/*
	 * walk down the list checking the flags to make sure MTCH was set,
	 * if not complain
	 */
	for (pt = pathead; pt != NULL; pt = pt->fow) {
		if (pt->flgs & MTCH)
			continue;
		if (!wban) {
			warn(1, "WARNING! These patterns were not matched:");
			++wban;
		}
		(void)fprintf(stderr, "%s\n", pt->pstr);
	}
}

/*
 * pat_sel()
 *	the archive member which matches a pattern was selected. Mark the
 *	pattern as having selected an archive member. arcn->pat points at the
 *	pattern that was matched. arcn->pat is set in pat_match()
 *
 *	NOTE: When the -c option is used, we are called when there was no match
 *	by pat_match() (that means we did match before the inverted sense of
 *	the logic). Now this seems really strange at first, but with -c  we
 *	need to keep track of those patterns that cause a archive member to NOT
 *	be selected (it found an archive member with a specified pattern)
 * Return:
 *	0 if the pattern pointed at by arcn->pat was tagged as creating a
 *	match, -1 otherwise.
 */

#if __STDC__
int
pat_sel(register ARCHD *arcn)
#else
int
pat_sel(arcn)
	register ARCHD *arcn;
#endif
{
	register PATTERN *pt;
	register PATTERN **ppt;
	register int len;

	/*
	 * if no patterns just return
	 */
	if ((pathead == NULL) || ((pt = arcn->pat) == NULL))
		return(0);

	/*
	 * when we are NOT limited to a single match per pattern mark the
	 * pattern and return
	 */
	if (!nflag) {
		pt->flgs |= MTCH;
		return(0);
	}

	/*
	 * we reach this point only when we allow a single selected match per
	 * pattern, if the pattern matches a directory and we do not have -d 
	 * (dflag) we are done with this pattern. We may also be handed a file
	 * in the subtree of a directory. in that case when we are operating
	 * with -d, this pattern was already selected and we are done
	 */
	if (pt->flgs & DIR_MTCH)
		return(0);

	if (!dflag && ((pt->pend != NULL) || (arcn->type == PAX_DIR))) {
		/*
		 * ok we matched a directory and we are allowing
		 * subtree matches but because of the -n only its children will
		 * match. This is tagged as a DIR_MTCH type.
		 * WATCH IT, the code assumes that pt->pend points
		 * into arcn->name and arcn->name has not been modified.
		 * If not we will have a big mess. Yup this is another kludge
		 */

		/*
		 * if this was a prefix match, remove trailing part of path
		 * so we can copy it. Future matches will be exact prefix match
		 */
		if (pt->pend != NULL)
			*pt->pend = '\0';
			
		if ((pt->pstr = strdup(arcn->name)) == NULL) {
			warn(1, "Pattern select out of memory");
			if (pt->pend != NULL)
				*pt->pend = '/';
			pt->pend = NULL;
			return(-1);
		}

		/*
		 * put the trailing / back in the source string
		 */
		if (pt->pend != NULL) {
			*pt->pend = '/';
			pt->pend = NULL;
		}
		pt->plen = strlen(pt->pstr);

		/*
		 * strip off any trailing /, this should really never happen
		 */
		len = pt->plen - 1;
		if (*(pt->pstr + len) == '/') {
			*(pt->pstr + len) = '\0';
			pt->plen = len;
		} 
		pt->flgs = DIR_MTCH | MTCH;
		arcn->pat = pt;
		return(0);
	}

	/*
	 * we are then done with this pattern, so we delete it from the list
	 * because it can never be used for another match.
	 * Seems kind of strange to do for a -c, but the pax spec is really
	 * vague on the interaction of -c -n and -d. We assume that when -c
	 * and the pattern rejects a member (i.e. it matched it) it is done.
	 * In effect we place the order of the flags as having -c last.
	 */
	pt = pathead;
	ppt = &pathead;
	while ((pt != NULL) && (pt != arcn->pat)) {
		ppt = &(pt->fow);
		pt = pt->fow;
	}

	if (pt == NULL) {
		/*
		 * should never happen....
		 */
		warn(1, "Pattern list inconsistant");
		return(-1);
	}
	*ppt = pt->fow;
	(void)free((char *)pt);
	arcn->pat = NULL;
	return(0);
}

/*
 * pat_match()
 *	see if this archive member matches any supplied pattern, if a match
 *	is found, arcn->pat is set to point at the potential pattern. Later if
 *	this archive member is "selected" we process and mark the pattern as
 *	one which matched a selected archive member (see pat_sel())
 * Return:
 *	0 if this archive member should be processed, 1 if it should be 
 *	skipped and -1 if we are done with all patterns (and pax should quit
 *	looking for more members)
 */

#if __STDC__
int
pat_match(register ARCHD *arcn)
#else
int
pat_match(arcn)
	register ARCHD *arcn;
#endif
{
	register PATTERN *pt;

	arcn->pat = NULL;

	/*
	 * if there are no more patterns and we have -n (and not -c) we are
	 * done. otherwise with no patterns to match, matches all
	 */
	if (pathead == NULL) {
		if (nflag && !cflag)
			return(-1);
		return(0);
	}

	/*
	 * have to search down the list one at a time looking for a match.
	 */
	pt = pathead;
	while (pt != NULL) {
		/*
		 * check for a file name match unless we have DIR_MTCH set in
		 * this pattern then we want a prefix match
		 */
		if (pt->flgs & DIR_MTCH) {
			/*
			 * this pattern was matched before to a directory
			 * as we must have -n set for this (but not -d). We can
			 * only match CHILDREN of that directory so we must use
			 * an exact prefix match (no wildcards).
			 */
			if ((arcn->name[pt->plen] == '/') &&
			    (strncmp(pt->pstr, arcn->name, pt->plen) == 0))
				break;
		} else if (fn_match(pt->pstr, arcn->name, &pt->pend) == 0)
			break;
		pt = pt->fow;
	}

	/*
	 * return the result, remember that cflag (-c) inverts the sense of a
	 * match
	 */
	if (pt == NULL)
		return(cflag ? 0 : 1);

	/*
	 * we had a match, now when we invert the sense (-c) we reject this
	 * member. However we have to tag the pattern a being successful, (in a
	 * match, not in selecting a archive member) so we call pat_sel() here.
	 */
	arcn->pat = pt;
	if (!cflag)
		return(0);

	if (pat_sel(arcn) < 0)
		return(-1);
	arcn->pat = NULL;
	return(1);
}

/*
 * fn_match()
 * Return:
 *	0 if this archive member should be processed, 1 if it should be 
 *	skipped and -1 if we are done with all patterns (and pax should quit
 *	looking for more members)
 *	Note: *pend may be changed to show where the prefix ends.
 */

#if __STDC__
static int
fn_match(register char *pattern, register char *string, char **pend)
#else
static int
fn_match(pattern, string, pend)
	register char *pattern;
	register char *string;
	char **pend;
#endif
{
	register char c;
	char test;

	*pend = NULL;
	for (;;) {
		switch (c = *pattern++) {
		case '\0':
			/*
			 * Ok we found an exact match
			 */
			if (*string == '\0')
				return(0);

			/*
			 * Check if it is a prefix match
			 */
			if ((dflag == 1) || (*string != '/'))
				return(-1);

			/*
			 * It is a prefix match, remember where the trailing
			 * / is located
			 */
			*pend = string;
			return(0);
		case '?':
			if ((test = *string++) == '\0')
				return (-1);
			break;
		case '*':
			c = *pattern;
			/*
			 * Collapse multiple *'s. 
			 */
			while (c == '*')
				c = *++pattern;

			/*
			 * Optimized hack for pattern with a * at the end
			 */
			if (c == '\0')
				return (0);

			/*
			 * General case, use recursion.
			 */
			while ((test = *string) != '\0') {
				if (!fn_match(pattern, string, pend))
					return (0);
				++string;
			}
			return (-1);
		case '[':
			/*
			 * range match
			 */
			if (((test = *string++) == '\0') ||
			    ((pattern = range_match(pattern, test)) == NULL))
				return (-1);
			break;
		case '\\':
		default:
			if (c != *string++)
				return (-1);
			break;
		}
	}