Aminet 1/Aminet - June 1993 [Walnut Creek].iso/usenet/sources/volume2/util/wns

Internet Message Format | 1988-10-20 | 52.1 KB

Path: xanth!mcnc!rutgers!mit-eddie!ll-xn!adelie!infinet!ulowell!page
From: [e-mail] (Bob Page)
Newsgroups: comp.sources.amiga
Subject: v02i001:  Windowed search (context grep)
Message-ID: <[e-mail]>
Date: 19 Oct 88 00:05:16 GMT
Organization: University of Lowell, Computer Science Dept.
Lines: 2143
Approved: [e-mail]

Submitted-by: [e-mail] (Mark Rinfret)
Posting-number: Volume 2, Issue 1
Archive-name: util/wns

Here's a little search utility which appeared in one of the major
sources groups recently (unix? misc?).  I made some minor changes to
the program proper and added in some regular expression stuff that I
had with a copy of NGrep.  I can't take credit for anything original
here, but it was an easy port so I thought I'd pass it along.

Mark Rinfret, 10/18/88
----------------------Apply Scissors Here-------------------------------
#! /bin/sh
# This is a shell archive.  Remove anything before this line, then unpack
# it by saving it into a file and typing "sh file".  To overwrite existing
# files, type "sh file -c".  You can also feed this as standard input via
# unshar, or by typing "sh <file", e.g..  If this archive is complete, you
# will see the following message at the end:
#        "End of archive 1 (of 1)."
# Contents:  Makefile regexp.h regmagic.h regerror.c regexp.c wns.c
#   wns.man wns.1
# Wrapped by mrr@mrramiga on Sun Oct  9 21:50:20 1988
# This shar was created for Amiga and may have pathnames which
# are incompatible with Unix.  Replace colon (:) with slash (/)
# in offending pathnames.
if test -f Makefile -a "${1}" != "-c" ; then
  echo shar: Will not over-write existing file \"Makefile\"
else
echo shar: Extracting \"Makefile\" \(675 characters\)
sed "s/^X//" >Makefile <<'END_OF_Makefile'
X# Makefile for wns
X#
XCC = cc
X
X# Define in CFLAGS:
X#    SYSINC    if include file hierarchy includes the sys/ directory
X#    REGEX    if using berkeley-style re_exec() and re_comp()
X#    REGCMP    if using regcmp() and regex()
X#    REGCOMP if using regcomp() and regexec()
X#    OS_UNIX if running under unix (or AmigaDOS)
X#    AMIGA   if running under AmigaDOS
X#    OS_CPM    if running under CP/M80
X#    STRCSPN if you need the strcspn() function.
X#
X#
X#CFLAGS=-DOS_UNIX -DREGCMP -DSYSINC
XCFLAGS=-DOS_UNIX -DAMIGA -DREGCOMP -DSTRCSPN -n
X#
X# Define LIBS to reflect the librar[y][ies] needed to fetch the r/e routines.
X#
XLIBS=-lc
X
X#
XWNSOBJS=wns.o regexp.o regerror.o
X
Xwns:    $(WNSOBJS)
X    ln $(WNSOBJS) $(LIBS) -o wns
END_OF_Makefile
if test 675 -ne `wc -c <Makefile`; then
    echo shar: \"Makefile\" unpacked with wrong size!
fi
# end of overwriting check
fi
if test -f regexp.h -a "${1}" != "-c" ; then
  echo shar: Will not over-write existing file \"regexp.h\"
else
echo shar: Extracting \"regexp.h\" \(574 characters\)
sed "s/^X//" >regexp.h <<'END_OF_regexp.h'
X/*
X * Definitions etc. for regexp(3) routines.
X *
X * Caveat:  this is V8 regexp(3) [actually, a reimplementation thereof],
X * not the System V one.
X */
X#define NSUBEXP  10
Xtypedef struct regexp {
X    char *startp[NSUBEXP];
X    char *endp[NSUBEXP];
X    char regstart;        /* Internal use only. */
X    char reganch;        /* Internal use only. */
X    char *regmust;        /* Internal use only. */
X    int regmlen;        /* Internal use only. */
X    char program[1];    /* Unwarranted chumminess with compiler. */
X} regexp;
X
Xextern regexp *regcomp();
Xextern int regexec();
Xextern void regsub();
Xextern void regerror();
END_OF_regexp.h
if test 574 -ne `wc -c <regexp.h`; then
    echo shar: \"regexp.h\" unpacked with wrong size!
fi
# end of overwriting check
fi
if test -f regmagic.h -a "${1}" != "-c" ; then
  echo shar: Will not over-write existing file \"regmagic.h\"
else
echo shar: Extracting \"regmagic.h\" \(153 characters\)
sed "s/^X//" >regmagic.h <<'END_OF_regmagic.h'
X/*
X * The first byte of the regexp internal "program" is actually this magic
X * number; the start node begins in the second byte.
X */
X#define    MAGIC    0234
END_OF_regmagic.h
if test 153 -ne `wc -c <regmagic.h`; then
    echo shar: \"regmagic.h\" unpacked with wrong size!
fi
# end of overwriting check
fi
if test -f regerror.c -a "${1}" != "-c" ; then
  echo shar: Will not over-write existing file \"regerror.c\"
else
echo shar: Extracting \"regerror.c\" \(170 characters\)
sed "s/^X//" >regerror.c <<'END_OF_regerror.c'
X#include <stdio.h>
X
Xvoid
Xregerror(s)
Xchar *s;
X{
X#ifdef ERRAVAIL
X    error("regexp: %s", s);
X#else
X    fprintf(stderr, "regexp(3): %s", s);
X    exit(1);
X#endif
X    /* NOTREACHED */
X}
END_OF_regerror.c
if test 170 -ne `wc -c <regerror.c`; then
    echo shar: \"regerror.c\" unpacked with wrong size!
fi
# end of overwriting check
fi
if test -f regexp.c -a "${1}" != "-c" ; then
  echo shar: Will not over-write existing file \"regexp.c\"
else
echo shar: Extracting \"regexp.c\" \(27732 characters\)
sed "s/^X//" >regexp.c <<'END_OF_regexp.c'
X/*
X * regcomp and regexec -- regsub and regerror are elsewhere
X *
X *    Copyright (c) 1986 by University of Toronto.
X *    Written by Henry Spencer.  Not derived from licensed software.
X *
X *    Permission is granted to anyone to use this software for any
X *    purpose on any computer system, and to redistribute it freely,
X *    subject to the following restrictions:
X *
X *    1. The author is not responsible for the consequences of use of
X *        this software, no matter how awful, even if they arise
X *        from defects in it.
X *
X *    2. The origin of this software must not be misrepresented, either
X *        by explicit claim or by omission.
X *
X *    3. Altered versions must be plainly marked as such, and must not
X *        be misrepresented as being the original software.
X *
X * Beware that some of this code is subtly aware of the way operator
X * precedence is structured in regular expressions.  Serious changes in
X * regular-expression syntax might require a total rethink.
X
X * 10/09/88 - This code was altered by Mark R. Rinfret for compatibility
X * with the Amiga. ([e-mail])
X */
X#include <stdio.h>
X#include "regexp.h"
X#include "regmagic.h"
X
X
X/*
X * The "internal use only" fields in regexp.h are present to pass info from
X * compile to execute that permits the execute phase to run lots faster on
X * simple cases.  They are:
X *
X * regstart    char that must begin a match; '\0' if none obvious
X * reganch    is the match anchored (at beginning-of-line only)?
X * regmust    string (pointer into program) that match must include, or NULL
X * regmlen    length of regmust string
X *
X * Regstart and reganch permit very fast decisions on suitable starting points
X * for a match, cutting down the work a lot.  Regmust permits fast rejection
X * of lines that cannot possibly match.  The regmust tests are costly enough
X * that regcomp() supplies a regmust only if the r.e. contains something
X * potentially expensive (at present, the only such thing detected is * or +
X * at the start of the r.e., which can involve a lot of backup).  Regmlen is
X * supplied because the test in regexec() needs it and regcomp() is computing
X * it anyway.
X */
X
X/*
X * Structure for regexp "program".  This is essentially a linear encoding
X * of a nondeterministic finite-state machine (aka syntax charts or
X * "railroad normal form" in parsing technology).  Each node is an opcode
X * plus a "next" pointer, possibly plus an operand.  "Next" pointers of
X * all nodes except BRANCH implement concatenation; a "next" pointer with
X * a BRANCH on both ends of it is connecting two alternatives.  (Here we
X * have one of the subtle syntax dependencies:  an individual BRANCH (as
X * opposed to a collection of them) is never concatenated with anything
X * because of operator precedence.)  The operand of some types of node is
X * a literal string; for others, it is a node leading into a sub-FSM.  In
X * particular, the operand of a BRANCH node is the first node of the branch.
X * (NB this is *not* a tree structure:  the tail of the branch connects
X * to the thing following the set of BRANCHes.)  The opcodes are:
X */
X
X/* definition    number    opnd?    meaning */
X#define    END    0    /* no    End of program. */
X#define    BOL    1    /* no    Match "" at beginning of line. */
X#define    EOL    2    /* no    Match "" at end of line. */
X#define    ANY    3    /* no    Match any one character. */
X#define    ANYOF    4    /* str    Match any character in this string. */
X#define    ANYBUT    5    /* str    Match any character not in this string. */
X#define    BRANCH    6    /* node    Match this alternative, or the next... */
X#define    BACK    7    /* no    Match "", "next" ptr points backward. */
X#define    EXACTLY    8    /* str    Match this string. */
X#define    NOTHING    9    /* no    Match empty string. */
X#define    STAR    10    /* node    Match this (simple) thing 0 or more times. */
X#define    PLUS    11    /* node    Match this (simple) thing 1 or more times. */
X#define    OPEN    20    /* no    Mark this point in input as start of #n. */
X            /*    OPEN+1 is number 1, etc. */
X#define    CLOSE    30    /* no    Analogous to OPEN. */
X
X/*
X * Opcode notes:
X *
X * BRANCH    The set of branches constituting a single choice are hooked
X *        together with their "next" pointers, since precedence prevents
X *        anything being concatenated to any individual branch.  The
X *        "next" pointer of the last BRANCH in a choice points to the
X *        thing following the whole choice.  This is also where the
X *        final "next" pointer of each individual branch points; each
X *        branch starts with the operand node of a BRANCH node.
X *
X * BACK        Normal "next" pointers all implicitly point forward; BACK
X *        exists to make loop structures possible.
X *
X * STAR,PLUS    '?', and complex '*' and '+', are implemented as circular
X *        BRANCH structures using BACK.  Simple cases (one character
X *        per match) are implemented with STAR and PLUS for speed
X *        and to minimize recursive plunges.
X *
X * OPEN,CLOSE    ...are numbered at compile time.
X */
X
X/*
X * A node is one char of opcode followed by two chars of "next" pointer.
X * "Next" pointers are stored as two 8-bit pieces, high order first.  The
X * value is a positive offset from the opcode of the node containing it.
X * An operand, if any, simply follows the node.  (Note that much of the
X * code generation knows about this implicit relationship.)
X *
X * Using two bytes for the "next" pointer is vast overkill for most things,
X * but allows patterns to get big without disasters.
X */
X#define    OP(p)    (*(p))
X#define    NEXT(p)    (((*((p)+1)&0377)<<8) + *((p)+2)&0377)
X#define    OPERAND(p)    ((p) + 3)
X
X/*
X * See regmagic.h for one further detail of program structure.
X */
X
X
X/*
X * Utility definitions.
X */
X#ifndef CHARBITS
X#define    UCHARAT(p)    ((int)*(unsigned char *)(p))
X#else
X#define    UCHARAT(p)    ((int)*(p)&CHARBITS)
X#endif
X
X#define    FAIL(m)    { regerror(m); return(NULL); }
X#define    ISMULT(c)    ((c) == '*' || (c) == '+' || (c) == '?')
X#define    META    "^$.[()|?+*\\"
X
X/*
X * Flags to be passed up and down.
X */
X#define    HASWIDTH    01    /* Known never to match null string. */
X#define    SIMPLE        02    /* Simple enough to be STAR/PLUS operand. */
X#define    SPSTART        04    /* Starts with * or +. */
X#define    WORST        0    /* Worst case. */
X
X/*
X * Global work variables for regcomp().
X */
Xstatic char *regparse;        /* Input-scan pointer. */
Xstatic int regnpar;        /* () count. */
Xstatic char regdummy;
Xstatic char *regcode;        /* Code-emit pointer; ®dummy = don't. */
Xstatic long regsize;        /* Code size. */
X
X/*
X * Forward declarations for regcomp()'s friends.
X */
X#ifndef STATIC
X#define    STATIC    static
X#endif
XSTATIC char *reg();
XSTATIC char *regbranch();
XSTATIC char *regpiece();
XSTATIC char *regatom();
XSTATIC char *regnode();
XSTATIC char *regnext();
XSTATIC void regc();
XSTATIC void reginsert();
XSTATIC void regtail();
XSTATIC void regoptail();
X#ifdef STRCSPN
XSTATIC int strcspn();
X#endif
X
X/*
X - regcomp - compile a regular expression into internal code
X *
X * We can't allocate space until we know how big the compiled form will be,
X * but we can't compile it (and thus know how big it is) until we've got a
X * place to put the code.  So we cheat:  we compile it twice, once with code
X * generation turned off and size counting turned on, and once "for real".
X * This also means that we don't allocate space until we are sure that the
X * thing really will compile successfully, and we never have to move the
X * code and thus invalidate pointers into it.  (Note that it has to be in
X * one piece because free() must be able to free it all.)
X *
X * Beware that the optimization-preparation code in here knows about some
X * of the structure of the compiled regexp.
X */
Xregexp *
Xregcomp(exp)
Xchar *exp;
X{
X    register regexp *r;
X    register char *scan;
X    register char *longest;
X    register int len;
X    int flags;
X    extern char *malloc();
X
X    if (exp == NULL)
X        FAIL("NULL argument");
X
X    /* First pass: determine size, legality. */
X    regparse = exp;
X    regnpar = 1;
X    regsize = 0L;
X    regcode = ®dummy;
X    regc(MAGIC);
X    if (reg(0, &flags) == NULL)
X        return(NULL);
X
X    /* Small enough for pointer-storage convention? */
X    if (regsize >= 32767L)        /* Probably could be 65535L. */
X        FAIL("regexp too big");
X
X    /* Allocate space. */
X    r = (regexp *)malloc(sizeof(regexp) + (unsigned)regsize);
X    if (r == NULL)
X        FAIL("out of space");
X
X    /* Second pass: emit code. */
X    regparse = exp;
X    regnpar = 1;
X    regcode = r->program;
X    regc(MAGIC);
X    if (reg(0, &flags) == NULL)
X        return(NULL);
X
X    /* Dig out information for optimizations. */
X    r->regstart = '\0';    /* Worst-case defaults. */
X    r->reganch = 0;
X    r->regmust = NULL;
X    r->regmlen = 0;
X    scan = r->program+1;            /* First BRANCH. */
X    if (OP(regnext(scan)) == END) {        /* Only one top-level choice. */
X        scan = OPERAND(scan);
X
X        /* Starting-point info. */
X        if (OP(scan) == EXACTLY)
X            r->regstart = *OPERAND(scan);
X        else if (OP(scan) == BOL)
X            r->reganch++;
X
X        /*
X         * If there's something expensive in the r.e., find the
X         * longest literal string that must appear and make it the
X         * regmust.  Resolve ties in favor of later strings, since
X         * the regstart check works with the beginning of the r.e.
X         * and avoiding duplication strengthens checking.  Not a
X         * strong reason, but sufficient in the absence of others.
X         */
X        if (flags&SPSTART) {
X            longest = NULL;
X            len = 0;
X            for (; scan != NULL; scan = regnext(scan))
X                if (OP(scan) == EXACTLY && strlen(OPERAND(scan)) >= len) {
X                    longest = OPERAND(scan);
X                    len = strlen(OPERAND(scan));
X                }
X            r->regmust = longest;
X            r->regmlen = len;
X        }
X    }
X
X    return(r);
X}
X
X/*
X - reg - regular expression, i.e. main body or parenthesized thing
X *
X * Caller must absorb opening parenthesis.
X *
X * Combining parenthesis handling with the base level of regular expression
X * is a trifle forced, but the need to tie the tails of the branches to what
X * follows makes it hard to avoid.
X */
Xstatic char *
Xreg(paren, flagp)
Xint paren;            /* Parenthesized? */
Xint *flagp;
X{
X    register char *ret;
X    register char *br;
X    register char *ender;
X    register int parno;
X    int flags;
X
X    *flagp = HASWIDTH;    /* Tentatively. */
X
X    /* Make an OPEN node, if parenthesized. */
X    if (paren) {
X        if (regnpar >= NSUBEXP)
X            FAIL("too many ()");
X        parno = regnpar;
X        regnpar++;
X        ret = regnode(OPEN+parno);
X    } else
X        ret = NULL;
X
X    /* Pick up the branches, linking them together. */
X    br = regbranch(&flags);
X    if (br == NULL)
X        return(NULL);
X    if (ret != NULL)
X        regtail(ret, br);    /* OPEN -> first. */
X    else
X        ret = br;
X    if (!(flags&HASWIDTH))
X        *flagp &= ~HASWIDTH;
X    *flagp |= flags&SPSTART;
X    while (*regparse == '|') {
X        regparse++;
X        br = regbranch(&flags);
X        if (br == NULL)
X            return(NULL);
X        regtail(ret, br);    /* BRANCH -> BRANCH. */
X        if (!(flags&HASWIDTH))
X            *flagp &= ~HASWIDTH;
X        *flagp |= flags&SPSTART;
X    }
X
X    /* Make a closing node, and hook it on the end. */
X    ender = regnode((paren) ? CLOSE+parno : END);
X    regtail(ret, ender);
X
X    /* Hook the tails of the branches to the closing node. */
X    for (br = ret; br != NULL; br = regnext(br))
X        regoptail(br, ender);
X
X    /* Check for proper termination. */
X    if (paren && *regparse++ != ')') {
X        FAIL("unmatched ()");
X    } else if (!paren && *regparse != '\0') {
X        if (*regparse == ')') {
X            FAIL("unmatched ()");
X        } else
X            FAIL("junk on end");    /* "Can't happen". */
X        /* NOTREACHED */
X    }
X
X    return(ret);
X}
X
X/*
X - regbranch - one alternative of an | operator
X *
X * Implements the concatenation operator.
X */
Xstatic char *
Xregbranch(flagp)
Xint *flagp;
X{
X    register char *ret;
X    register char *chain;
X    register char *latest;
X    int flags;
X
X    *flagp = WORST;        /* Tentatively. */
X
X    ret = regnode(BRANCH);
X    chain = NULL;
X    while (*regparse != '\0' && *regparse != '|' && *regparse != ')') {
X        latest = regpiece(&flags);
X        if (latest == NULL)
X            return(NULL);
X        *flagp |= flags&HASWIDTH;
X        if (chain == NULL)    /* First piece. */
X            *flagp |= flags&SPSTART;
X        else
X            regtail(chain, latest);
X        chain = latest;
X    }
X    if (chain == NULL)    /* Loop ran zero times. */
X        (void) regnode(NOTHING);
X
X    return(ret);
X}
X
X/*
X - regpiece - something followed by possible [*+?]
X *
X * Note that the branching code sequences used for ? and the general cases
X * of * and + are somewhat optimized:  they use the same NOTHING node as
X * both the endmarker for their branch list and the body of the last branch.
X * It might seem that this node could be dispensed with entirely, but the
X * endmarker role is not redundant.
X */
Xstatic char *
Xregpiece(flagp)
Xint *flagp;
X{
X    register char *ret;
X    register char op;
X    register char *next;
X    int flags;
X
X    ret = regatom(&flags);
X    if (ret == NULL)
X        return(NULL);
X
X    op = *regparse;
X    if (!ISMULT(op)) {
X        *flagp = flags;
X        return(ret);
X    }
X
X    if (!(flags&HASWIDTH) && op != '?')
X        FAIL("*+ operand could be empty");
X    *flagp = (op != '+') ? (WORST|SPSTART) : (WORST|HASWIDTH);
X
X    if (op == '*' && (flags&SIMPLE))
X        reginsert(STAR, ret);
X    else if (op == '*') {
X        /* Emit x* as (x&|), where & means "self". */
X        reginsert(BRANCH, ret);            /* Either x */
X        regoptail(ret, regnode(BACK));        /* and loop */
X        regoptail(ret, ret);            /* back */
X        regtail(ret, regnode(BRANCH));        /* or */
X        regtail(ret, regnode(NOTHING));        /* null. */
X    } else if (op == '+' && (flags&SIMPLE))
X        reginsert(PLUS, ret);
X    else if (op == '+') {
X        /* Emit x+ as x(&|), where & means "self". */
X        next = regnode(BRANCH);            /* Either */
X        regtail(ret, next);
X        regtail(regnode(BACK), ret);        /* loop back */
X        regtail(next, regnode(BRANCH));        /* or */
X        regtail(ret, regnode(NOTHING));        /* null. */
X    } else if (op == '?') {
X        /* Emit x? as (x|) */
X        reginsert(BRANCH, ret);            /* Either x */
X        regtail(ret, regnode(BRANCH));        /* or */
X        next = regnode(NOTHING);        /* null. */
X        regtail(ret, next);
X        regoptail(ret, next);
X    }
X    regparse++;
X    if (ISMULT(*regparse))
X        FAIL("nested *?+");
X
X    return(ret);
X}
X
X/*
X - regatom - the lowest level
X *
X * Optimization:  gobbles an entire sequence of ordinary characters so that
X * it can turn them into a single node, which is smaller to store and
X * faster to run.  Backslashed characters are exceptions, each becoming a
X * separate node; the code is simpler that way and it's not worth fixing.
X */
Xstatic char *
Xregatom(flagp)
Xint *flagp;
X{
X    register char *ret;
X    int flags;
X
X    *flagp = WORST;        /* Tentatively. */
X
X    switch (*regparse++) {
X    case '^':
X        ret = regnode(BOL);
X        break;
X    case '$':
X        ret = regnode(EOL);
X        break;
X    case '.':
X        ret = regnode(ANY);
X        *flagp |= HASWIDTH|SIMPLE;
X        break;
X    case '[': {
X            register int class;
X            register int classend;
X
X            if (*regparse == '^') {    /* Complement of range. */
X                ret = regnode(ANYBUT);
X                regparse++;
X            } else
X                ret = regnode(ANYOF);
X            if (*regparse == ']' || *regparse == '-')
X                regc(*regparse++);
X            while (*regparse != '\0' && *regparse != ']') {
X                if (*regparse == '-') {
X                    regparse++;
X                    if (*regparse == ']' || *regparse == '\0')
X                        regc('-');
X                    else {
X                        class = UCHARAT(regparse-2)+1;
X                        classend = UCHARAT(regparse);
X                        if (class > classend+1)
X                            FAIL("invalid [] range");
X                        for (; class <= classend; class++)
X                            regc(class);
X                        regparse++;
X                    }
X                } else
X                    regc(*regparse++);
X            }
X            regc('\0');
X            if (*regparse != ']')
X                FAIL("unmatched []");
X            regparse++;
X            *flagp |= HASWIDTH|SIMPLE;
X        }
X        break;
X    case '(':
X        ret = reg(1, &flags);
X        if (ret == NULL)
X            return(NULL);
X        *flagp |= flags&(HASWIDTH|SPSTART);
X        break;
X    case '\0':
X    case '|':
X    case ')':
X        FAIL("internal urp");    /* Supposed to be caught earlier. */
X        break;
X    case '?':
X    case '+':
X    case '*':
X        FAIL("?+* follows nothing");
X        break;
X    case '\\':
X        if (*regparse == '\0')
X            FAIL("trailing \\");
X        ret = regnode(EXACTLY);
X        regc(*regparse++);
X        regc('\0');
X        *flagp |= HASWIDTH|SIMPLE;
X        break;
X    default: {
X            register int len;
X            register char ender;
X
X            regparse--;
X            len = strcspn(regparse, META);
X            if (len <= 0)
X                FAIL("internal disaster");
X            ender = *(regparse+len);
X            if (len > 1 && ISMULT(ender))
X                len--;        /* Back off clear of ?+* operand. */
X            *flagp |= HASWIDTH;
X            if (len == 1)
X                *flagp |= SIMPLE;
X            ret = regnode(EXACTLY);
X            while (len > 0) {
X                regc(*regparse++);
X                len--;
X            }
X            regc('\0');
X        }
X        break;
X    }
X
X    return(ret);
X}
X
X/*
X - regnode - emit a node
X */
Xstatic char *            /* Location. */
Xregnode(op)
Xchar op;
X{
X    register char *ret;
X    register char *ptr;
X
X    ret = regcode;
X    if (ret == ®dummy) {
X        regsize += 3;
X        return(ret);
X    }
X
X    ptr = ret;
X    *ptr++ = op;
X    *ptr++ = '\0';        /* Null "next" pointer. */
X    *ptr++ = '\0';
X    regcode = ptr;
X
X    return(ret);
X}
X
X/*
X - regc - emit (if appropriate) a byte of code
X */
Xstatic void
Xregc(b)
Xchar b;
X{
X    if (regcode != ®dummy)
X        *regcode++ = b;
X    else
X        regsize++;
X}
X
X/*
X - reginsert - insert an operator in front of already-emitted operand
X *
X * Means relocating the operand.
X */
Xstatic void
Xreginsert(op, opnd)
Xchar op;
Xchar *opnd;
X{
X    register char *src;
X    register char *dst;
X    register char *place;
X
X    if (regcode == ®dummy) {
X        regsize += 3;
X        return;
X    }
X
X    src = regcode;
X    regcode += 3;
X    dst = regcode;
X    while (src > opnd)
X        *--dst = *--src;
X
X    place = opnd;        /* Op node, where operand used to be. */
X    *place++ = op;
X    *place++ = '\0';
X    *place++ = '\0';
X}
X
X/*
X - regtail - set the next-pointer at the end of a node chain
X */
Xstatic void
Xregtail(p, val)
Xchar *p;
Xchar *val;
X{
X    register char *scan;
X    register char *temp;
X    register int offset;
X
X    if (p == ®dummy)
X        return;
X
X    /* Find last node. */
X    scan = p;
X    for (;;) {
X        temp = regnext(scan);
X        if (temp == NULL)
X            break;
X        scan = temp;
X    }
X
X    if (OP(scan) == BACK)
X        offset = scan - val;
X    else
X        offset = val - scan;
X    *(scan+1) = (offset>>8)&0377;
X    *(scan+2) = offset&0377;
X}
X
X/*
X - regoptail - regtail on operand of first argument; nop if operandless
X */
Xstatic void
Xregoptail(p, val)
Xchar *p;
Xchar *val;
X{
X    /* "Operandless" and "op != BRANCH" are synonymous in practice. */
X    if (p == NULL || p == ®dummy || OP(p) != BRANCH)
X        return;
X    regtail(OPERAND(p), val);
X}
X
X/*
X * regexec and friends
X */
X
X/*
X * Global work variables for regexec().
X */
Xstatic char *reginput;        /* String-input pointer. */
Xstatic char *regbol;        /* Beginning of input, for ^ check. */
Xstatic char **regstartp;    /* Pointer to startp array. */
Xstatic char **regendp;        /* Ditto for endp. */
X
X/*
X * Forwards.
X */
XSTATIC int regtry();
XSTATIC int regmatch();
XSTATIC int regrepeat();
X
X#ifdef DEBUG
Xint regnarrate = 0;
Xvoid regdump();
XSTATIC char *regprop();
X#endif
X
X/*
X - regexec - match a regexp against a string
X */
Xint
Xregexec(prog, string)
Xregister regexp *prog;
Xregister char *string;
X{
X    register char *s;
X    extern char *strchr();
X
X    /* Be paranoid... */
X    if (prog == NULL || string == NULL) {
X        regerror("NULL parameter");
X        return(0);
X    }
X
X    /* Check validity of program. */
X    if (UCHARAT(prog->program) != MAGIC) {
X        regerror("corrupted program");
X        return(0);
X    }
X
X    /* If there is a "must appear" string, look for it. */
X    if (prog->regmust != NULL) {
X        s = string;
X        while ((s = strchr(s, prog->regmust[0])) != NULL) {
X            if (strncmp(s, prog->regmust, prog->regmlen) == 0)
X                break;    /* Found it. */
X            s++;
X        }
X        if (s == NULL)    /* Not present. */
X            return(0);
X    }
X
X    /* Mark beginning of line for ^ . */
X    regbol = string;
X
X    /* Simplest case:  anchored match need be tried only once. */
X    if (prog->reganch)
X        return(regtry(prog, string));
X
X    /* Messy cases:  unanchored match. */
X    s = string;
X    if (prog->regstart != '\0')
X        /* We know what char it must start with. */
X        while ((s = strchr(s, prog->regstart)) != NULL) {
X            if (regtry(prog, s))
X                return(1);
X            s++;
X        }
X    else
X        /* We don't -- general case. */
X        do {
X            if (regtry(prog, s))
X                return(1);
X        } while (*s++ != '\0');
X
X    /* Failure. */
X    return(0);
X}
X
X/*
X - regtry - try match at specific point
X */
Xstatic int            /* 0 failure, 1 success */
Xregtry(prog, string)
Xregexp *prog;
Xchar *string;
X{
X    register int i;
X    register char **sp;
X    register char **ep;
X
X    reginput = string;
X    regstartp = prog->startp;
X    regendp = prog->endp;
X
X    sp = prog->startp;
X    ep = prog->endp;
X    for (i = NSUBEXP; i > 0; i--) {
X        *sp++ = NULL;
X        *ep++ = NULL;
X    }
X    if (regmatch(prog->program + 1)) {
X        prog->startp[0] = string;
X        prog->endp[0] = reginput;
X        return(1);
X    } else
X        return(0);
X}
X
X/*
X - regmatch - main matching routine
X *
X * Conceptually the strategy is simple:  check to see whether the current
X * node matches, call self recursively to see whether the rest matches,
X * and then act accordingly.  In practice we make some effort to avoid
X * recursion, in particular by going through "ordinary" nodes (that don't
X * need to know whether the rest of the match failed) by a loop instead of
X * by recursion.
X */
Xstatic int            /* 0 failure, 1 success */
Xregmatch(prog)
Xchar *prog;
X{
X    register char *scan;    /* Current node. */
X    char *next;        /* Next node. */
X    extern char *strchr();
X
X    scan = prog;
X#ifdef DEBUG
X    if (scan != NULL && regnarrate)
X        fprintf(stderr, "%s(\n", regprop(scan));
X#endif
X    while (scan != NULL) {
X#ifdef DEBUG
X        if (regnarrate)
X            fprintf(stderr, "%s...\n", regprop(scan));
X#endif
X        next = regnext(scan);
X
X        switch (OP(scan)) {
X        case BOL:
X            if (reginput != regbol)
X                return(0);
X            break;
X        case EOL:
X            if (*reginput != '\0')
X                return(0);
X            break;
X        case ANY:
X            if (*reginput == '\0')
X                return(0);
X            reginput++;
X            break;
X        case EXACTLY: {
X                register int len;
X                register char *opnd;
X
X                opnd = OPERAND(scan);
X                /* Inline the first character, for speed. */
X                if (*opnd != *reginput)
X                    return(0);
X                len = strlen(opnd);
X                if (len > 1 && strncmp(opnd, reginput, len) != 0)
X                    return(0);
X                reginput += len;
X            }
X            break;
X        case ANYOF:
X            if (*reginput == '\0' || strchr(OPERAND(scan), *reginput) == NULL)
X                return(0);
X            reginput++;
X            break;
X        case ANYBUT:
X            if (*reginput == '\0' || strchr(OPERAND(scan), *reginput) != NULL)
X                return(0);
X            reginput++;
X            break;
X        case NOTHING:
X            break;
X        case BACK:
X            break;
X        case OPEN+1:
X        case OPEN+2:
X        case OPEN+3:
X        case OPEN+4:
X        case OPEN+5:
X        case OPEN+6:
X        case OPEN+7:
X        case OPEN+8:
X        case OPEN+9: {
X                register int no;
X                register char *save;
X
X                no = OP(scan) - OPEN;
X                save = reginput;
X
X                if (regmatch(next)) {
X                    /*
X                     * Don't set startp if some later
X                     * invocation of the same parentheses
X                     * already has.
X                     */
X                    if (regstartp[no] == NULL)
X                        regstartp[no] = save;
X                    return(1);
X                } else
X                    return(0);
X            }
X            break;
X        case CLOSE+1:
X        case CLOSE+2:
X        case CLOSE+3:
X        case CLOSE+4:
X        case CLOSE+5:
X        case CLOSE+6:
X        case CLOSE+7:
X        case CLOSE+8:
X        case CLOSE+9: {
X                register int no;
X                register char *save;
X
X                no = OP(scan) - CLOSE;
X                save = reginput;
X
X                if (regmatch(next)) {
X                    /*
X                     * Don't set endp if some later
X                     * invocation of the same parentheses
X                     * already has.
X                     */
X                    if (regendp[no] == NULL)
X                        regendp[no] = save;
X                    return(1);
X                } else
X                    return(0);
X            }
X            break;
X        case BRANCH: {
X                register char *save;
X
X                if (OP(next) != BRANCH)        /* No choice. */
X                    next = OPERAND(scan);    /* Avoid recursion. */
X                else {
X                    do {
X                        save = reginput;
X                        if (regmatch(OPERAND(scan)))
X                            return(1);
X                        reginput = save;
X                        scan = regnext(scan);
X                    } while (scan != NULL && OP(scan) == BRANCH);
X                    return(0);
X                    /* NOTREACHED */
X                }
X            }
X            break;
X        case STAR:
X        case PLUS: {
X                register char nextch;
X                register int no;
X                register char *save;
X                register int min;
X
X                /*
X                 * Lookahead to avoid useless match attempts
X                 * when we know what character comes next.
X                 */
X                nextch = '\0';
X                if (OP(next) == EXACTLY)
X                    nextch = *OPERAND(next);
X                min = (OP(scan) == STAR) ? 0 : 1;
X                save = reginput;
X                no = regrepeat(OPERAND(scan));
X                while (no >= min) {
X                    /* If it could work, try it. */
X                    if (nextch == '\0' || *reginput == nextch)
X                        if (regmatch(next))
X                            return(1);
X                    /* Couldn't or didn't -- back up. */
X                    no--;
X                    reginput = save + no;
X                }
X                return(0);
X            }
X            break;
X        case END:
X            return(1);    /* Success! */
X            break;
X        default:
X            regerror("memory corruption");
X            return(0);
X            break;
X        }
X
X        scan = next;
X    }
X
X    /*
X     * We get here only if there's trouble -- normally "case END" is
X     * the terminating point.
X     */
X    regerror("corrupted pointers");
X    return(0);
X}
X
X/*
X - regrepeat - repeatedly match something simple, report how many
X */
Xstatic int
Xregrepeat(p)
Xchar *p;
X{
X    register int count = 0;
X    register char *scan;
X    register char *opnd;
X
X    scan = reginput;
X    opnd = OPERAND(p);
X    switch (OP(p)) {
X    case ANY:
X        count = strlen(scan);
X        scan += count;
X        break;
X    case EXACTLY:
X        while (*opnd == *scan) {
X            count++;
X            scan++;
X        }
X        break;
X    case ANYOF:
X        while (*scan != '\0' && strchr(opnd, *scan) != NULL) {
X            count++;
X            scan++;
X        }
X        break;
X    case ANYBUT:
X        while (*scan != '\0' && strchr(opnd, *scan) == NULL) {
X            count++;
X            scan++;
X        }
X        break;
X    default:        /* Oh dear.  Called inappropriately. */
X        regerror("internal foulup");
X        count = 0;    /* Best compromise. */
X        break;
X    }
X    reginput = scan;
X
X    return(count);
X}
X
X/*
X - regnext - dig the "next" pointer out of a node
X */
Xstatic char *
Xregnext(p)
Xregister char *p;
X{
X    register int offset;
X
X    if (p == ®dummy)
X        return(NULL);
X
X    offset = NEXT(p);
X    if (offset == 0)
X        return(NULL);
X
X    if (OP(p) == BACK)
X        return(p-offset);
X    else
X        return(p+offset);
X}
X
X#ifdef DEBUG
X
XSTATIC char *regprop();
X
X/*
X - regdump - dump a regexp onto stdout in vaguely comprehensible form
X */
Xvoid
Xregdump(r)
Xregexp *r;
X{
X    register char *s;
X    register char op = EXACTLY;    /* Arbitrary non-END op. */
X    register char *next;
X    extern char *strchr();
X
X
X    s = r->program + 1;
X    while (op != END) {    /* While that wasn't END last time... */
X        op = OP(s);
X        printf("%2d%s", s-r->program, regprop(s));    /* Where, what. */
X        next = regnext(s);
X        if (next == NULL)        /* Next ptr. */
X            printf("(0)");
X        else
X            printf("(%d)", (s-r->program)+(next-s));
X        s += 3;
X        if (op == ANYOF || op == ANYBUT || op == EXACTLY) {
X            /* Literal string, where present. */
X            while (*s != '\0') {
X                putchar(*s);
X                s++;
X            }
X            s++;
X        }
X        putchar('\n');
X    }
X
X    /* Header fields of interest. */
X    if (r->regstart != '\0')
X        printf("start `%c' ", r->regstart);
X    if (r->reganch)
X        printf("anchored ");
X    if (r->regmust != NULL)
X        printf("must have \"%s\"", r->regmust);
X    printf("\n");
X}
X
X/*
X - regprop - printable representation of opcode
X */
Xstatic char *
Xregprop(op)
Xchar *op;
X{
X    register char *p;
X    static char buf[50];
X
X    (void) strcpy(buf, ":");
X
X    switch (OP(op)) {
X    case BOL:
X        p = "BOL";
X        break;
X    case EOL:
X        p = "EOL";
X        break;
X    case ANY:
X        p = "ANY";
X        break;
X    case ANYOF:
X        p = "ANYOF";
X        break;
X    case ANYBUT:
X        p = "ANYBUT";
X        break;
X    case BRANCH:
X        p = "BRANCH";
X        break;
X    case EXACTLY:
X        p = "EXACTLY";
X        break;
X    case NOTHING:
X        p = "NOTHING";
X        break;
X    case BACK:
X        p = "BACK";
X        break;
X    case END:
X        p = "END";
X        break;
X    case OPEN+1:
X    case OPEN+2:
X    case OPEN+3:
X    case OPEN+4:
X    case OPEN+5:
X    case OPEN+6:
X    case OPEN+7:
X    case OPEN+8:
X    case OPEN+9:
X        sprintf(buf+strlen(buf), "OPEN%d", OP(op)-OPEN);
X        p = NULL;
X        break;
X    case CLOSE+1:
X    case CLOSE+2:
X    case CLOSE+3:
X    case CLOSE+4:
X    case CLOSE+5:
X    case CLOSE+6:
X    case CLOSE+7:
X    case CLOSE+8:
X    case CLOSE+9:
X        sprintf(buf+strlen(buf), "CLOSE%d", OP(op)-CLOSE);
X        p = NULL;
X        break;
X    case STAR:
X        p = "STAR";
X        break;
X    case PLUS:
X        p = "PLUS";
X        break;
X    default:
X        regerror("corrupted opcode");
X        break;
X    }
X    if (p != NULL)
X        (void) strcat(buf, p);
X    return(buf);
X}
X#endif
X
X/*
X * The following is provided for those people who do not have strcspn() in
X * their C libraries.  They should get off their butts and do something
X * about it; at least one public-domain implementation of those (highly
X * useful) string routines has been published on Usenet.
X */
X#ifdef STRCSPN
X/*
X * strcspn - find length of initial segment of s1 consisting entirely
X * of characters not from s2
X */
X
Xstatic int
Xstrcspn(s1, s2)
Xchar *s1;
Xchar *s2;
X{
X    register char *scan1;
X    register char *scan2;
X    register int count;
X
X    count = 0;
X    for (scan1 = s1; *scan1 != '\0'; scan1++) {
X        for (scan2 = s2; *scan2 != '\0';)    /* ++ moved down. */
X            if (*scan1 == *scan2++)
X                return(count);
X        count++;
X    }
X    return(count);
X}
X#endif
END_OF_regexp.c
if test 27732 -ne `wc -c <regexp.c`; then
    echo shar: \"regexp.c\" unpacked with wrong size!
fi
# end of overwriting check
fi
if test -f wns.c -a "${1}" != "-c" ; then
  echo shar: Will not over-write existing file \"wns.c\"
else
echo shar: Extracting \"wns.c\" \(12950 characters\)
sed "s/^X//" >wns.c <<'END_OF_wns.c'
X/* wns.c - Search for string and print window of lines around it.
X
X        Nov 19 1984     Mark Mallett   ([e-mail])
X
Xmem    860224    Modified to do r/e (regular expression) parsing on unix
Xmem    860324    Added -f, -n; added code to number lines correctly on
X        output.
Xmem    870325    Added support for regcmp()/regex() style regular expression
X        library; redid some conditionals to provide better mix'n'match.
Xmem    870326    Don't try to print the filename if reading from stdin.
X        Add -w option.  Fix a small problem which occasionally allowed
X        the separator to come out between adjacent lines of the file.
Xmem    871119    Fix semantics of call to regcmp(): the NULL terminating the
X        argument list was missing.  It worked, but probably only
X        due to some bizarre coincidence.
X
X    Changes by Mark Rinfret for Amiga ([e-mail])
X
Xmrr    881009    Use V8 regexp routines (since I had 'em)
X
X*/
X
X/* The appropriate defines are done in the makefile */
X/* #define    OS_UNIX */    /* Define this for unix systems */
X/* #define    SYSINC */    /* Define this for sys/ include hierarchy */
X/* #define    REGEX */    /* Define this for re_comp/re_exec library */
X/* #define    REGCMP */    /* Define this to use regcmp/regex */
X/* #define    REGCOMP */    /* Define this to use regcomp/regexec */
X/* #define    OS_CPM */    /* Define this for CP/M-80 */
X
X
X/* Don't touch these */
X#define    NOREGEXP        /* Set this for no regular expression */
X#ifdef    REGEX
X#undef    NOREGEXP
X#endif    REGEX
X
X#ifdef    REGCMP
X#undef    NOREGEXP
X#endif    REGCMP
X
X#ifdef REGCOMP
X#undef NOREGEXP
X#endif
X
X
X#ifdef OS_CPM
X#include "stdio.h"
X#include "ctype.h"
X#endif OS_CPM
X
X#ifdef OS_UNIX
X#include <stdio.h>
X#include <ctype.h>
X
X#ifdef    SYSINC
X#include <sys/types.h>
X#include <sys/dir.h>
X#else    /* !SYSINC */
X#ifndef AMIGA
X#include <types.h>
X#include <dir.h>
X#endif
X#endif    SYSINC
X#endif OS_UNIX
X
Xchar *calloc();
Xchar *fgets();
X
X/* Local definitions */
X
X#ifndef    NULL
X#define    NULL    ((char *)0)
X#endif    NULL
X
X#ifndef NUL
X#define NUL     '\000'
X#endif
X
X#ifndef TRUE
X#define TRUE    1
X#define FALSE   0
X#endif
X
X
X/* Internal data declared global */
X
X
X/* Internal routines */
X
X
X/* External data */
X
X
X/* External routines */
X
X#ifdef    REGEX            /* re_comp/ re_exec */
Xextern    char    *re_comp();        /* r/e compile */
Xextern    int    re_exec();        /* r/e exec */
X#endif    REGEX
X
X#ifdef    REGCMP            /* regcmp/regex */
Xextern    char    *regcmp();        /* r/e compile */
Xextern    char    *regex();        /* r/e exec */
X#endif    REGCMP
X
X#ifdef REGCOMP            /* regcomp/regexec */
Xextern char    *regcomp();
Xextern char    *regexec();
X#endif
X
X
X/* Local data */
X
Xstatic  int     Debug={FALSE};          /* Debug enabled flag */
Xstatic  int     Lcur = {0};             /* Current line (in Lines array) */
Xstatic  char    **Lines = {(char **)NULL};       /* Lines pointer array */
Xstatic  int     Linlen = {100};         /* Line length */
Xstatic  int     Lone = {0};             /* Line one (in Lines array) */
Xstatic    int    Nmr = {0};        /* Number of matched regions */
Xstatic  char    *Pat = {NULL};          /* Pattern */
Xstatic    char    Shwfile = {TRUE};    /* Show file name... */
Xstatic    char    Shwline = {TRUE};    /* Show line number */
Xstatic  int     Waft = {0};             /* Window after */
Xstatic  int     Wbef = {0};             /* Window before */
Xstatic  int     Wsiz = {0};             /* Window size */
X
X#ifdef    REGEX        /* regex style r/e manipulations */
Xchar        *Re;        /* Result from re_comp() */
X#endif    REGEX
X
X#ifdef    REGCMP        /* regcmp style r/e */
Xchar        *Re;        /* Result from regcmp() */
X#endif    REGCMP
X
X#ifdef REGCOMP
Xchar        *Re;        /* Result from regcomp() */
X#endif REGCOMP
X
Xmain (argc, argv)
X
Xint             argc;           /* Argument count */
Xchar            **argv;         /* Argument values */
X
X{
Xint             i;              /* Scratch */
Xint             n;              /* Scratch again */
Xint             c;              /* A character */
Xchar            *aptr;          /* Argument pointer */
Xint             nf;             /* number of files on command line */
X
Xnf = 0;                         /* No files on line */
X
Xfor (i = 1; i < argc; i++)      /* Look at args */
X    {
X    if (argv[i][0] != '-')      /* If option */
X        {
X        if (Pat == NULL)        /* If no pattern yet given */
X        {
X            Pat = argv[i];      /*  point here */
X#ifdef    REGEX
X        if ((Re = re_comp(Pat)) != NULL)
X            {
X        fprintf(stderr, "wns: %s\n", re);
X        exit(1);
X        }
X#endif    REGEX
X
X#ifdef    REGCMP
X        if ((Re = regcmp(Pat, NULL)) == NULL)
X            {
X        fprintf(stderr, "wns: error in regular expression.\n");
X        exit(1);
X        }
X#endif    REGCMP
X
X#ifdef    REGCOMP
X        if ((Re = regcomp(Pat, NULL)) == NULL)
X            {
X        fprintf(stderr, "wns: error in regular expression.\n");
X        exit(1);
X        }
X#endif    REGCOMP
X
X        }
X        else                    /* This must be a file to search */
X            {
X#ifdef AMIGA
X            /* On the Amiga, we may have to do wildcard expansion. */
X#ifdef AZTEC_C
X            /* Aztec provides a method for this.  I don't know what
X             * Lattice provides.  Sorry.
X             */
X            char *scdir();        /* Aztec C wildcard expansion */
X            char *fName;        /* filename back from scdir() */
X            int  isWild;
X            char testChar;
X
X            /* Because the Aztec scdir() routine is so slow (due to
X             * directory scanning), avoid its use if possible.  Only call
X             * scdir() if we have a filename with wildcard characters.
X             */
X            isWild = 0;
X            for (fName = argv[i]; testChar = *fName++; )
X                if (testChar == '*' || testChar == '?') {
X                    ++isWild;    /* Filename has wildcards. */
X                    break;
X                }
X
X            if (isWild) {
X                while (fName = scdir(argv[i])) {
X                    nf++;
X                    dosrch(fName);
X                }
X            }
X            else {
X                nf++;
X                dosrch(argv[i]);
X            }
X#else
X            /* Lattice variant of wildcard handling goes here. */
X            nf++;
X            dosrch(argv[i]);
X#endif
X#else
X            nf++;               /* Count it */
X            dosrch (argv[i]);   /* Search */
X#endif
X            }
X        }
X
X    else                        /* Option char */
X        {
X        c = argv[i][1];         /* Get option char */
X        if (isupper(c))         /* Trap idiot definition of tolower */
X            c = tolower(c);     /* Don't care about case */
X        n = i;
X        aptr = NULL;            /* Find arg, if any */
X        if (argv[i][2] != NUL)
X            {
X            aptr = &argv[i][2];
X            n = i;              /* Where to set i if we use this arg */
X            }
X        else if (i < argc-1)    /* use next.. */
X            {
X            n = i+1;
X            aptr = argv[n];
X            }
X
X        switch (c)              /* Process the option */
X            {
X            case 'a':           /* Lines after */
X                Waft = atoi (aptr);
X                Lines = NULL;
X                i = n;
X                break;
X
X            case 'b':           /* Lines before */
X                Wbef = atoi (aptr);
X                Lines = (char **)NULL;
X                i = n;
X                break;
X
X            case 'd':           /* Enable debugging */
X                Debug = TRUE;
X                break;
X
X        case 'f':        /* Suppress filename on output */
X            Shwfile = FALSE;
X        break;
X
X            case 'l':           /* Line length */
X                Linlen = atoi (aptr);
X                Lines = NULL;
X                i = n;
X                break;
X
X        case 'n':        /* Suppress line number on output */
X            Shwline = FALSE;
X        break;
X
X            case 'w':           /* Window: lines before and after */
X                Waft = Wbef = atoi (aptr);
X                Lines = NULL;
X                i = n;
X                break;
X
X            default:
X                fprintf (stderr, "Invalid option %s\n",argv[i]);
X                exit(1);
X            }
X        }
X    }
X
Xif ( Pat == NULL )        /* If no pattern given */
X    {
X    fprintf(stderr,
X"usage: wns [-a n] [-b n] [-d] [-f] [-l n] [-n] [-w n] pattern [filename... ]\n");
X    exit(1);
X    }
X
Xif (nf == 0)                    /* No files processed ? */
X    dosrch (NULL);              /* Do standard input */
X
X    exit(0);
X}
X/*
X
X*//* dosrch (ifnm)
X
X        Perform the search
X
XAccepts :
X
X        ifn             Input file name
X
X
XReturns :
X
X
X*/
X
Xdosrch (ifnm)
X
Xchar            *ifnm;          /* Input filelname */
X
X{
XFILE            *ifp;           /* Input fp */
Xchar            *lptr;          /* Line pointer */
Xint             i;              /* Scratch */
Xint             prtaft;         /* Print-after count */
Xint             linnum;         /* Line number */
Xint        nlb;        /* Number of lines buffered */
X
Xif (ifnm != NULL)               /* If file name given */
X    {
X    ifp = fopen (ifnm, "r");    /* Open it for read access */
X    if (ifp == NULL)
X        {
X        fprintf (stderr, "Can not open file %s\n", ifnm);
X        return;
X        }
X    }
Xelse
X    ifp = stdin;
X
Xif (Lines == NULL)              /* If no line table allocated.. */
X    {
X    Wsiz = Wbef+2;              /* Determine total window size */
X    Lines = (char **) calloc (Wsiz, sizeof (char *));
X                                /* Allocate pointer table */
X    for (i = 0; i < Wsiz; i++)  /* Allocate line buffers */
X        Lines[i] = (char *) calloc (Linlen, sizeof(char));
X    }
X
XLcur = Lone = 0;                /* Setup line pointers */
Xnlb = 0;            /* No lines buffered */
Xlinnum = 0;                     /* Line number is zero */
Xprtaft = -(Wbef+1);        /* Make sure separator given first time */
X
Xfor (;;)                        /* Loop through the file */
X    {
X    lptr = Lines[Lcur];         /* Get pointer to current line */
X    if (++Lcur == Wsiz)         /* Bump curr pointer and wrap */
X        Lcur = 0;               /*  if hit end */
X    if (Lone == Lcur)           /* If wrapped to beginning of window */
X        if (++Lone == Wsiz)     /*  Bump beginning */
X            Lone = 0;           /*   and wrap if hit end */
X
X    if (fgets (lptr, Linlen, ifp) != lptr)
X        break;                  /*  if end of file */
X
X    linnum++;                   /* Count line number */
X    if (matlin (lptr))          /* If matching line */
X        {
X        if (prtaft < (-Wbef) )  /* Check for separator needed */
X            if ( (Nmr++ > 0 ) && ((Wbef > 0) || (Waft > 0)) )
X                printf ("-------------------\n");
X        while (Lone != Lcur)    /* Until we close the window */
X            {
X            shwlin (ifnm, linnum-nlb, Lines[Lone]);
X                                /* Show the line */
X            if (++Lone == Wsiz)
X                Lone = 0;
X        nlb--;
X            }
X    nlb = 0;        /* No lines buffered */
X        prtaft = Waft;          /* Print n lines after */
X        }
X
X    else                        /* Didn't match */
X        {
X        if (prtaft-- > 0)       /* If must print lines after */
X            {
X            shwlin (ifnm, linnum, lptr);
X                                /* Show the line */
X            Lone = Lcur;        /* Match pointers */
X            }
X    else if (nlb < Wbef)    /* Count lines buffered */
X        nlb++;
X        }
X    }
X
Xif (ifnm != NULL)
X    fclose (ifp);
X}
X/*
X
X*//* shwlin (fnm, linnum, line)
X
X        Show a matching line
X
X
XAccepts :
X
X        fnm             File name
X
X        linnum          Line number
X
X        line            Line to show
X
X
XReturns :
X
X
X*/
X
Xshwlin (fnm, linnum, line)
X
Xchar            *fnm;           /* File name */
Xint             linnum;         /* Line number */
Xchar            *line;          /* Line (with newline at end) to print */
X
X{
Xif (Shwfile && ( fnm != NULL) )
X    printf("%s%s", fnm, Shwline?" ":":");
Xif (Shwline)
X    printf("@%05d%:", linnum);
Xprintf ("%s", line);
X}
X/*
X
X*//* matlin (line)
X
X        Perform match against pattern and line
X
X
XAccepts :
X
X        line            Address of line to match
X
X
XReturns :
X
X        <value>         TRUE if match
X                        FALSE if not
X
X
X*/
X
X
Xint matlin (line)
X
Xchar            *line;          /* Line to match */
X
X{
Xint        rtncode;        /* Return value from this routine */
X
X
X#ifdef    NOREGEXP
Xchar            *pptr, *lptr, *tlptr;
Xint             c1,c2;
X#endif    NOREGEXP
X
Xif (Debug)
X    printf ("Matching %s against %s", Pat, line);
X
X#ifdef    REGEX
Xrtncode = re_exec(line);    /* Hand off to r/e evaluator */
X#endif    REGEX
X
X#ifdef    REGCMP
Xrtncode = ( regex( Re, line ) != NULL );
X#endif    REGCMP
X
X#ifdef REGCOMP
Xrtncode = ( regexec( Re, line ) != NULL );
X#endif REGCOMP
X
X#ifdef    NOREGEX        /* Have to do menial comparison.. */
Xlptr = line;                    /* Init line pointer */
X
Xfor ( rtncode = -1; rtncode < 0; )
X    {
X    tlptr = lptr++;             /* Get temp ptr to line */
X    pptr = Pat;                 /* Get ptr to pattern */
X    while (TRUE)
X        {
X        if ((c1 = *pptr++) == NUL)
X            {
X        rtncode = 1;    /* GOOD return value */
X        break;
X            }
X        if ((c2 = *tlptr++) == NUL)
X            {
X        rtncode = 0;    /* BAD return value */
X        break;
X            }
X        if (isupper(c1))
X            c1 = tolower(c1);
X        if (isupper(c2))
X            c2 = tolower(c2);
X        if (c1 != c2)
X            break;
X        }
X    }
X#endif    NOREGEX
X
X
Xif (Debug)
X    printf("matlin returned %s\n", rtncode?"TRUE":"FALSE");
Xreturn(rtncode);
X}
X
X
END_OF_wns.c
if test 12950 -ne `wc -c <wns.c`; then
    echo shar: \"wns.c\" unpacked with wrong size!
fi
# end of overwriting check
fi
if test -f wns.man -a "${1}" != "-c" ; then
  echo shar: Will not over-write existing file \"wns.man\"
else
echo shar: Extracting \"wns.man\" \(2415 characters\)
sed "s/^X//" >wns.man <<'END_OF_wns.man'
X
X
X
X     WNS(1)                                                     WNS(1)
X
X
X
X     NAME
X          wns - windowing search
X
X     SYNOPSIS
X          wns [-a nnn] [-b nnn] [-l nnn] [-w nnn] pattern [file ... ]
X
X     DESCRIPTION
X          _w_n_s searches through a file or list of files for occurances
X          of a particular pattern, and prints a window of lines around
X          each match point.
X
X          Options which may be given are as follows:
X
X          -a nnn
X               (After) specifies that nnn lines following the matching
X               line will be printed.  default is 0.
X
X          -b nnn
X               (Before) specifies that nnn lines preceding the
X               matching line will be printed.  default is 0.
X
X          -d   Enables debugging information.  Not a very interesting
X               option.
X
X          -f   Suppress printing of the filename on each output line.
X
X          -l nnn
X               Sets the maximum line length to nnn.  Lines longer than
X               this will be truncated to this length before attempting
X               to match them to the pattern as well as when printing
X               them.  Default is 100.
X
X          -n   Suppress printing of the line number on each output
X               line.
X
X          -w nnn
X               Sets the window size to nnn.  This is the same as -a
X               nnn -b nnn.
X
X          _w_n_s outputs lines in the following format:
X
X          filename @nnnnn: text
X
X          where _f_i_l_e_n_a_m_e is the name of the file containing the
X          matching text and may be suppressed with the -f option,
X          _l_n_n_n_n is the line number of the displayed line and may be
X          suppressed with the -n option, and _t_e_x_t is the line from the
X          file.  Additionally, if the total window size is greater
X          than 1 (that is, more than zero lines before or after), then
X          non-adjacent text areas are separated by a short dashed
X          line.
X
X
X
X
X     Page 1                                          (printed 9/23/88)
X
X
X
X
X
X
X     WNS(1)                                                     WNS(1)
X
X
X
X     FILES
X          /usr/local/bin/wns /usr/local/src/wns/*
X
X     CREDITS TO
X          M. Mallett  ([e-mail])
X
X     BUGS
X          You tell me..
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X     Page 2                                          (printed 9/23/88)
X
X
X
END_OF_wns.man
echo shar: 23 control characters may be missing from \"wns.man\"
if test 2415 -ne `wc -c <wns.man`; then
    echo shar: \"wns.man\" unpacked with wrong size!
fi
# end of overwriting check
fi
if test -f wns.1 -a "${1}" != "-c" ; then
  echo shar: Will not over-write existing file \"wns.1\"
else
echo shar: Extracting \"wns.1\" \(1655 characters\)
sed "s/^X//" >wns.1 <<'END_OF_wns.1'
X.TH WNS 1
X.SH NAME
Xwns \- windowing search
X.SH SYNOPSIS
X.B wns
X[-a nnn]
X[-b nnn]
X[-l nnn]
X[-w nnn]
Xpattern
X[file ... ]
X.SH DESCRIPTION
X.I wns
Xsearches through a file or list of files for occurances of a particular
Xpattern, and prints a window of lines around each match point.
X.PP
XOptions which may be given are as follows:
X.TP
X.B \-a\ nnn
X(After) specifies that nnn lines following the matching line will be
Xprinted.  default is 0.
X.TP
X.B \-b\ nnn
X(Before) specifies that nnn lines preceding the matching line will be
Xprinted.  default is 0.
X.TP
X.B \-d
XEnables debugging information.  Not a very interesting option.
X.TP
X.B \-f
XSuppress printing of the filename on each output line.
X.TP
X.B \-l\ nnn
XSets the maximum line length to nnn.  Lines longer than this will be
Xtruncated to this length before attempting to match them to the pattern as
Xwell as when printing them.  Default is 100.
X.TP
X.B \-n
XSuppress printing of the line number on each output line.
X.TP
X.B \-w\ nnn
XSets the window size to nnn.  This is the same as -a nnn -b nnn.
X.PP
X.I wns
Xoutputs lines in the following format:
X.PP
Xfilename @nnnnn: text
X.PP
Xwhere
X.I filename
Xis the name of the file containing the matching text and may be suppressed
Xwith the -f option,
X.I lnnnn
Xis the line number of the displayed line and may be suppressed with the
X-n option, and
X.I text
Xis the line from the file.
XAdditionally, if the total window size is greater than 1 (that is, more than
Xzero lines before or after), then non-adjacent text areas are separated by
Xa short dashed line.
X.SH FILES
X/usr/local/bin/wns /usr/local/src/wns/*
X.SH "CREDITS TO"
XM. Mallett  ([e-mail])
X.SH BUGS
XYou tell me..
END_OF_wns.1
if test 1655 -ne `wc -c <wns.1`; then
    echo shar: \"wns.1\" unpacked with wrong size!
fi
# end of overwriting check
fi
echo shar: End of archive 1 \(of 1\).
cp /dev/null ark1isdone
MISSING=""
for I in 1 ; do
    if test ! -f ark${I}isdone ; then
    MISSING="${MISSING} ${I}"
    fi
done
if test "${MISSING}" = "" ; then
    echo You have unpacked all 1 archives.
    rm -f ark[1-9]isdone
else
    echo You still need to unpack the following archives:
    echo "        " ${MISSING}
fi
##  End of shell archive.
exit 0


--
Bob Page, U of Lowell CS Dept.  [e-mail]  ulowell!page
"I can't tell the difference between ABC News and Hill Street Blues" -Bono