Garbo/Garbo.cdr/pc/source/stevie.zoo/stevie.4

Text File | 1990-03-14 | 56.1 KB | 2,453 lines

: This is a shar archive.  Extract with sh, not csh.
: The rest of this file will extract:
: param.c ptrfunc.c regexp.c regsub.c screen.c
echo extracting - param.c
sed 's/^X//' > param.c << '!EOR!'
X/* $Header: /nw/tony/src/stevie/src/RCS/param.c,v 1.10 89/08/02 10:59:10 tony Exp $
X *
X * Code to handle user-settable parameters. This is all pretty much table-
X * driven. To add a new parameter, put it in the params array, and add a
X * macro for it in param.h. If it's a numeric parameter, add any necessary
X * bounds checks to doset(). String parameters aren't currently supported.
X */
X
X#include "stevie.h"
X
Xstruct    param    params[] = {
X
X    { "tabstop",    "ts",        8,    P_NUM },
X    { "scroll",    "scroll",    12,    P_NUM },
X    { "report",    "report",    5,    P_NUM },
X    { "lines",    "lines",    25,    P_NUM },
X
X    { "vbell",    "vb",        TRUE,    P_BOOL },
X    { "showmatch",    "sm",        FALSE,    P_BOOL },
X    { "wrapscan",    "ws",        TRUE,    P_BOOL },
X    { "errorbells",    "eb",        FALSE,    P_BOOL },
X    { "showmode",    "mo",        FALSE,    P_BOOL },
X    { "backup",    "bk",        FALSE,    P_BOOL },
X    { "return",    "cr",        TRUE,    P_BOOL },
X    { "list",    "list",        FALSE,    P_BOOL },
X    { "ignorecase",    "ic",        FALSE,    P_BOOL },
X    { "autoindent",    "ai",        FALSE,    P_BOOL },
X    { "number",    "nu",        FALSE,    P_BOOL },
X    { "modelines",    "ml",        FALSE,    P_BOOL },
X    { "tildeop",    "to",        FALSE,    P_BOOL },
X    { "terse",    "terse",    FALSE,    P_BOOL },
X    { "tagstack",    "tg",        FALSE,    P_BOOL },
X    { "color",    "co",        -1,    P_NUM  },
X    { "",        "",        0,    0, }        /* end marker */
X
X};
X
Xstatic    void    showparms();
X
Xvoid
Xdoset(arg)
Xchar    *arg;        /* parameter string */
X{
X    register int    i;
X    register char    *s;
X    bool_t    did_lines = FALSE;
X    bool_t    state = TRUE;        /* new state of boolean parms. */
X
X    if (arg == NULL) {
X        showparms(FALSE);
X        return;
X    }
X    if (strncmp(arg, "all", 3) == 0) {
X        showparms(TRUE);
X        return;
X    }
X    if (strncmp(arg, "no", 2) == 0) {
X        state = FALSE;
X        arg += 2;
X    }
X
X    for (i=0; params[i].fullname[0] != NUL ;i++) {
X        s = params[i].fullname;
X        if (strncmp(arg, s, strlen(s)) == 0)    /* matched full name */
X            break;
X        s = params[i].shortname;
X        if (strncmp(arg, s, strlen(s)) == 0)    /* matched short name */
X            break;
X    }
X
X    if (params[i].fullname[0] != NUL) {    /* found a match */
X        if (params[i].flags & P_NUM) {
X            did_lines = (i == P_LI);
X            if (arg[strlen(s)] != '=' || state == FALSE)
X                emsg("Invalid set of numeric parameter");
X            else {
X                params[i].value = atoi(arg+strlen(s)+1);
X                params[i].flags |= P_CHANGED;
X                if (i==P_CO)  setcolor (P(P_CO));
X            }
X        } else /* boolean */ {
X            if (arg[strlen(s)] == '=')
X                emsg("Invalid set of boolean parameter");
X            else {
X                params[i].value = state;
X                params[i].flags |= P_CHANGED;
X            }
X        }
X    } else
X        emsg("Unrecognized 'set' option");
X
X    /*
X     * Update the screen in case we changed something like "tabstop"
X     * or "list" that will change its appearance.
X     */
X    updatescreen();
X
X    if (did_lines) {
X        Rows = P(P_LI);
X        P(P_LI) = Rows = setrows( Rows );
X                    /* setrows() is system-dependent.
X                     * This assures no impossible values
X                     * will be set.
X                     */
X        if (screenalloc() == -1) return;    /* allocate new screen buffers */
X        screenclear();
X        updatescreen();
X    }
X    /*
X     * Check the bounds for numeric parameters here
X     */
X    if (P(P_TS) <= 0 || P(P_TS) > 32) {
X        emsg("Invalid tab size specified");
X        P(P_TS) = 8;
X        return;
X    }
X
X    if (P(P_SS) <= 0 || P(P_SS) > Rows) {
X        emsg("Invalid scroll size specified");
X        P(P_SS) = 12;
X        return;
X    }
X
X#ifndef    TILDEOP
X    if (P(P_TO)) {
X        emsg("Tilde-operator not enabled");
X        P(P_TO) = FALSE;
X        return;
X    }
X#endif
X    /*
X     * Check for another argument, and call doset() recursively, if
X     * found. If any argument results in an error, no further
X     * parameters are processed.
X     */
X    while (*arg != ' ' && *arg != '\t') {    /* skip to next white space */
X        if (*arg == NUL)
X            return;            /* end of parameter list */
X        arg++;
X    }
X    while (*arg == ' ' || *arg == '\t')    /* skip to next non-white */
X        arg++;
X
X    if (*arg)
X        doset(arg);    /* recurse on next parameter */
X}
X
Xstatic    void
Xshowparms(all)
Xbool_t    all;    /* show ALL parameters */
X{
X    register struct    param    *p;
X    char    buf[64];
X
X    gotocmd(TRUE, 0);
X    outstr("Parameters:\r\n");
X
X    for (p = ¶ms[0]; p->fullname[0] != NUL ;p++) {
X        if (!all && ((p->flags & P_CHANGED) == 0))
X            continue;
X        if (p->flags & P_BOOL)
X            sprintf(buf, "\t%s%s\r\n",
X                (p->value ? "" : "no"), p->fullname);
X        else
X            sprintf(buf, "\t%s=%d\r\n", p->fullname, p->value);
X
X        outstr(buf);
X    }
X    wait_return();
X}
!EOR!
echo extracting - ptrfunc.c
sed 's/^X//' > ptrfunc.c << '!EOR!'
X/* $Header: /nw/tony/src/stevie/src/RCS/ptrfunc.c,v 1.5 89/03/11 22:43:12 tony Exp $
X *
X * The routines in this file attempt to imitate many of the operations
X * that used to be performed on simple character pointers and are now
X * performed on LPTR's. This makes it easier to modify other sections
X * of the code. Think of an LPTR as representing a position in the file.
X * Positions can be incremented, decremented, compared, etc. through
X * the functions implemented here.
X */
X
X#include "stevie.h"
X
X/*
X * inc(p)
X *
X * Increment the line pointer 'p' crossing line boundaries as necessary.
X * Return 1 when crossing a line, -1 when at end of file, 0 otherwise.
X */
Xint
Xinc(lp)
Xregister LPTR    *lp;
X{
X    register char    *p;
X
X    if (lp && lp->linep)
X        p = &(lp->linep->s[lp->index]);
X    else
X        return -1;
X
X    if (*p != NUL) {            /* still within line */
X        lp->index++;
X        return ((p[1] != NUL) ? 0 : 1);
X    }
X
X    if (lp->linep->next != Fileend->linep) {  /* there is a next line */
X        lp->index = 0;
X        lp->linep = lp->linep->next;
X        return 1;
X    }
X
X    return -1;
X}
X
X/*
X * dec(p)
X *
X * Decrement the line pointer 'p' crossing line boundaries as necessary.
X * Return 1 when crossing a line, -1 when at start of file, 0 otherwise.
X */
Xint
Xdec(lp)
Xregister LPTR    *lp;
X{
X    if (lp->index > 0) {            /* still within line */
X        lp->index--;
X        return 0;
X    }
X
X    if (lp->linep->prev != Filetop->linep) { /* there is a prior line */
X        lp->linep = lp->linep->prev;
X        lp->index = strlen(lp->linep->s);
X        return 1;
X    }
X
X    lp->index = 0;                /* stick at first char */
X    return -1;                /* at start of file */
X}
X
X/*
X * gchar(lp) - get the character at position "lp"
X */
Xint
Xgchar(lp)
Xregister LPTR    *lp;
X{
X    if (lp && lp->linep)
X        return (lp->linep->s[lp->index]);
X    else
X        return 0;
X}
X
X/*
X * pchar(lp, c) - put character 'c' at position 'lp'
X */
Xvoid
Xpchar(lp, c)
Xregister LPTR    *lp;
Xchar    c;
X{
X    lp->linep->s[lp->index] = c;
X}
X
X/*
X * pswap(a, b) - swap two position pointers
X */
Xvoid
Xpswap(a, b)
Xregister LPTR    *a, *b;
X{
X    LPTR    tmp;
X
X    tmp = *a;
X    *a  = *b;
X    *b  = tmp;
X}
X
X/*
X * Position comparisons
X */
X
Xbool_t
Xlt(a, b)
Xregister LPTR    *a, *b;
X{
X    register int    an, bn;
X
X    an = LINEOF(a);
X    bn = LINEOF(b);
X
X    if (an != bn)
X        return (an < bn);
X    else
X        return (a->index < b->index);
X}
X
X#if 0
Xbool_t
Xgt(a, b)
XLPTR    *a, *b;
X{
X    register int an, bn;
X
X    an = LINEOF(a);
X    bn = LINEOF(b);
X
X    if (an != bn)
X        return (an > bn);
X    else
X        return (a->index > b->index);
X}
X#endif
X
Xbool_t
Xequal(a, b)
Xregister LPTR    *a, *b;
X{
X    return (a->linep == b->linep && a->index == b->index);
X}
X
Xbool_t
Xltoreq(a, b)
Xregister LPTR    *a, *b;
X{
X    return (lt(a, b) || equal(a, b));
X}
X
X#if 0
Xbool_t
Xgtoreq(a, b)
XLPTR    *a, *b;
X{
X    return (gt(a, b) || equal(a, b));
X}
X#endif
!EOR!
echo extracting - regexp.c
sed 's/^X//' > regexp.c << '!EOR!'
X/* $Header: /nw/tony/src/stevie/src/RCS/regexp.c,v 1.5 89/07/07 16:27:11 tony Exp $
X *
X * NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE
X *
X * This is NOT the original regular expression code as written by
X * Henry Spencer. This code has been modified specifically for use
X * with the STEVIE editor, and should not be used apart from compiling
X * STEVIE. If you want a good regular expression library, get the
X * original code. The copyright notice that follows is from the
X * original.
X *
X * NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE
X *
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 */
X
X#include "env.h"
X
X#include <stdio.h>
X#include "regexp.h"
X#include "regmagic.h"
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#ifndef    ORIGINAL
X/*
X * The following supports the ability to ignore case in searches.
X */
X
X#include <ctype.h>
X
Xint reg_ic = 0;            /* set by callers to ignore case */
X
X/*
X * mkup - convert to upper case IF we're doing caseless compares
X */
X#define    mkup(c)        ((reg_ic && islower(c)) ? toupper(c) : (c))
X
X#endif
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, at_bol)
Xregister regexp *prog;
Xregister char *string;
Xint at_bol;
X{
X    register char *s;
X    extern char *cstrchr();
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 = cstrchr(s, prog->regmust[0])) != NULL) {
X            if (cstrncmp(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    if (at_bol)
X        regbol = string;    /* is possible to match bol */
X    else
X        regbol = NULL;        /* we aren't there, so don't match it */
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 = cstrchr(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 (mkup(*opnd) != mkup(*reginput))
X                    return(0);
X                len = strlen(opnd);
X                if (len > 1 && cstrncmp(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 (mkup(*opnd) == mkup(*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
X
Xint
Xcstrncmp(s1, s2, n)
Xchar    *s1, *s2;
Xint    n;
X{
X    char    *p, *S1, *S2, *strsave();
X    int    rval;
X
X    if (!reg_ic)
X        return (strncmp(s1, s2, n));
X
X    S1 = strsave(s1);
X    S2 = strsave(s2);
X
X    for (p = S1; *p ;p++)
X        if (islower(*p))
X            *p = toupper(*p);
X
X    for (p = S2; *p ;p++)
X        if (islower(*p))
X            *p = toupper(*p);
X
X    rval = strncmp(S1, S2, n);
X
X    free(S1);
X    free(S2);
X
X    return rval;
X}
X
Xchar *
Xcstrchr(s, c)
Xchar    *s;
Xchar    c;
X{
X    char    *p;
X
X    for (p = s; *p ;p++) {
X        if (mkup(*p) == mkup(c))
X            return p;
X    }
X    return NULL;
X}
!EOR!
echo extracting - regsub.c
sed 's/^X//' > regsub.c << '!EOR!'
X/* $Header: /nw/tony/src/stevie/src/RCS/regsub.c,v 1.4 89/03/11 22:43:30 tony Exp $
X *
X * NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE
X *
X * This is NOT the original regular expression code as written by
X * Henry Spencer. This code has been modified specifically for use
X * with the STEVIE editor, and should not be used apart from compiling
X * STEVIE. If you want a good regular expression library, get the
X * original code. The copyright notice that follows is from the
X * original.
X *
X * NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE
X *
X * regsub
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 */
X
X#include <stdio.h>
X#include "regexp.h"
X#include "regmagic.h"
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/*
X - regsub - perform substitutions after a regexp match
X */
Xvoid
Xregsub(prog, source, dest)
Xregexp *prog;
Xchar *source;
Xchar *dest;
X{
X    register char *src;
X    register char *dst;
X    register char c;
X    register int no;
X    register int len;
X    extern char *strncpy();
X
X    if (prog == NULL || source == NULL || dest == NULL) {
X        regerror("NULL parm to regsub");
X        return;
X    }
X    if (UCHARAT(prog->program) != MAGIC) {
X        regerror("damaged regexp fed to regsub");
X        return;
X    }
X
X    src = source;
X    dst = dest;
X    while ((c = *src++) != '\0') {
X        if (c == '&')
X            no = 0;
X        else if (c == '\\' && '0' <= *src && *src <= '9')
X            no = *src++ - '0';
X        else
X            no = -1;
X         if (no < 0) {    /* Ordinary character. */
X             if (c == '\\' && (*src == '\\' || *src == '&'))
X                 c = *src++;
X             *dst++ = c;
X         } else if (prog->startp[no] != NULL && prog->endp[no] != NULL) {
X            len = prog->endp[no] - prog->startp[no];
X            (void) strncpy(dst, prog->startp[no], len);
X            dst += len;
X            if (len != 0 && *(dst-1) == '\0') {    /* strncpy hit NUL. */
X                regerror("damaged match string");
X                return;
X            }
X        }
X    }
X    *dst++ = '\0';
X}
!EOR!
echo extracting - screen.c
sed 's/^X//' > screen.c << '!EOR!'
X/* $Header: /nw/tony/src/stevie/src/RCS/screen.c,v 1.8 89/08/02 09:26:33 tony Exp $
X *
X * Routines to manipulate the screen representations.
X */
X
X#include "stevie.h"
X
X/*
X * This gets set if we ignored an update request while input was pending.
X * We check this when the input is drained to see if the screen should be
X * updated.
X */
Xbool_t    need_redraw = FALSE;
X
X/*
X * The following variable is set (in filetonext) to the number of physical
X * lines taken by the line the cursor is on. We use this to avoid extra
X * calls to plines(). The optimized routines lfiletonext() and lnexttoscreen()
X * make sure that the size of the cursor line hasn't changed. If so, lines
X * below the cursor will move up or down and we need to call the routines
X * filetonext() and nexttoscreen() to examine the entire screen.
X */
Xstatic    int    Cline_size;    /* size (in rows) of the cursor line */
Xstatic    int    Cline_row;    /* starting row of the cursor line */
X
Xstatic    char    *mkline();    /* calculate line string for "number" mode */
X
X/*
X * filetonext()
X *
X * Based on the current value of Topchar, transfer a screenfull of
X * stuff from Filemem to Nextscreen, and update Botchar.
X */
X
Xstatic void
Xfiletonext()
X{
X    register int    row, col;
X    register char    *screenp = Nextscreen;
X    LPTR    memp;
X    LPTR    save;            /* save pos. in case line won't fit */
X    register char    *endscreen;
X    register char    *nextrow;
X    char    extra[16];
X    int    nextra = 0;
X    register int    c;
X    int    n;
X    bool_t    done;        /* if TRUE, we hit the end of the file */
X    bool_t    didline;    /* if TRUE, we finished the last line */
X    int    srow;        /* starting row of the current line */
X    int    lno;        /* number of the line we're doing */
X    int    coff;        /* column offset */
X
X    coff = P(P_NU) ? 8 : 0;
X
X    save = memp = *Topchar;
X
X    if (P(P_NU))
X        lno = cntllines(Filemem, Topchar);
X
X    /*
X     * The number of rows shown is Rows-1.
X     * The last line is the status/command line.
X     */
X    endscreen = &screenp[(Rows-1)*Columns];
X
X    done = didline = FALSE;
X    srow = row = col = 0;
X    /*
X     * We go one past the end of the screen so we can find out if the
X     * last line fit on the screen or not.
X     */
X    while ( screenp <= endscreen && !done) {
X
X
X        if (P(P_NU) && col == 0 && memp.index == 0) {
X            strcpy(extra, mkline(lno++));
X            nextra = 8;
X        }
X
X        /* Get the next character to put on the screen. */
X
X        /* The 'extra' array contains the extra stuff that is */
X        /* inserted to represent special characters (tabs, and */
X        /* other non-printable stuff.  The order in the 'extra' */
X        /* array is reversed. */
X
X        if ( nextra > 0 )
X            c = extra[--nextra];
X        else {
X            c = (unsigned)(0xff & gchar(&memp));
X            if (inc(&memp) == -1)
X                done = 1;
X            /* when getting a character from the file, we */
X            /* may have to turn it into something else on */
X            /* the way to putting it into 'Nextscreen'. */
X            if ( c == TAB && !P(P_LS) ) {
X                strcpy(extra,"        ");
X                /* tab amount depends on current column */
X                nextra = ((P(P_TS)-1) - (col - coff)%P(P_TS));
X                c = ' ';
X            }
X            else if ( c == NUL && P(P_LS) ) {
X                extra[0] = NUL;
X                nextra = 1;
X                c = '$';
X            } else if ( (n = chars[c].ch_size) > 1 ) {
X                char *p;
X                nextra = 0;
X                p = chars[c].ch_str;
X                /* copy 'ch-str'ing into 'extra' in reverse */
X                while ( n > 1 )
X                    extra[nextra++] = p[--n];
X                c = p[0];
X            }
X        }
X
X        if (screenp == endscreen) {
X            /*
X             * We're one past the end of the screen. If the
X             * current character is null, then we really did
X             * finish, so set didline = TRUE. In either case,
X             * break out because we're done.
X             */
X            dec(&memp);
X            if (memp.index != 0 && c == NUL) {
X                didline = TRUE;
X                inc(&memp);
X            }
X            break;
X        }
X
X        if ( c == NUL ) {
X            srow = ++row;
X            /*
X             * Save this position in case the next line won't
X             * fit on the screen completely.
X             */
X            save = memp;
X            /* get pointer to start of next row */
X            nextrow = &Nextscreen[row*Columns];
X            /* blank out the rest of this row */
X            while ( screenp != nextrow )
X                *screenp++ = ' ';
X            col = 0;
X            continue;
X        }
X        if ( col >= Columns ) {
X            row++;
X            col = 0;
X        }
X        /* store the character in Nextscreen */
X        *screenp++ = c;
X        col++;
X    }
X    /*
X     * If we didn't hit the end of the file, and we didn't finish
X     * the last line we were working on, then the line didn't fit.
X     */
X    if (!done && !didline) {
X        /*
X         * Clear the rest of the screen and mark the unused lines.
X         */
X        screenp = &Nextscreen[srow * Columns];
X        while (screenp < endscreen)
X            *screenp++ = ' ';
X        for (; srow < (Rows-1) ;srow++)
X            Nextscreen[srow * Columns] = '@';
X        *Botchar = save;
X        return;
X    }
X    /* make sure the rest of the screen is blank */
X    while ( screenp < endscreen )
X        *screenp++ = ' ';
X    /* put '~'s on rows that aren't part of the file. */
X    if ( col != 0 )
X        row++;
X    while ( row < Rows ) {
X        Nextscreen[row*Columns] = '~';
X        row++;
X    }
X    if (done)    /* we hit the end of the file */
X        *Botchar = *Fileend;
X    else
X        *Botchar = memp;    /* FIX - prev? */
X}
X
X/*
X * nexttoscreen
X *
X * Transfer the contents of Nextscreen to the screen, using Realscreen
X * to avoid unnecessary output.
X */
Xstatic void
Xnexttoscreen()
X{
X    register char    *np = Nextscreen;
X    register char    *rp = Realscreen;
X    register char    *endscreen;
X    register int    row = 0, col = 0;
X    int    gorow = -1, gocol = -1;
X
X    if (anyinput()) {
X        need_redraw = TRUE;
X        return;
X    }
X
X    endscreen = &np[(Rows-1)*Columns];
X
X    CUROFF;        /* disable cursor */
X
X    for ( ; np < endscreen ; np++,rp++ ) {
X        /* If desired screen (contents of Nextscreen) does not */
X        /* match what's really there, put it there. */
X        if ( *np != *rp ) {
X            /* if we are positioned at the right place, */
X            /* we don't have to use windgoto(). */
X            if (gocol != col || gorow != row) {
X                /*
X                 * If we're just off by one, don't send
X                 * an entire esc. seq. (this happens a lot!)
X                 */
X                if (gorow == row && gocol+1 == col) {
X                    outchar(*(np-1));
X                    gocol++;
X                } else
X                    windgoto(gorow=row,gocol=col);
X            }
X            outchar(*rp = *np);
X            gocol++;
X        }
X        if ( ++col >= Columns ) {
X            col = 0;
X            row++;
X        }
X    }
X    CURON;        /* enable cursor again */
X}
X
X/*
X * lfiletonext() - like filetonext() but only for cursor line
X *
X * Returns true if the size of the cursor line (in rows) hasn't changed.
X * This determines whether or not we need to call filetonext() to examine
X * the entire screen for changes.
X */
Xstatic bool_t
Xlfiletonext()
X{
X    register int    row, col;
X    register char    *screenp;
X    LPTR    memp;
X    register char    *nextrow;
X    char    extra[16];
X    int    nextra = 0;
X    register int    c;
X    int    n;
X    bool_t    eof;
X    int    lno;        /* number of the line we're doing */
X    int    coff;        /* column offset */
X
X    coff = P(P_NU) ? 8 : 0;
X
X    /*
X     * This should be done more efficiently.
X     */
X    if (P(P_NU))
X        lno = cntllines(Filemem, Curschar);
X
X    screenp = Nextscreen + (Cline_row * Columns);
X
X    memp = *Curschar;
X    memp.index = 0;
X
X    eof = FALSE;
X    col = 0;
X    row = Cline_row;
X
X    while (!eof) {
X
X        if (P(P_NU) && col == 0 && memp.index == 0) {
X            strcpy(extra, mkline(lno));
X            nextra = 8;
X        }
X
X        /* Get the next character to put on the screen. */
X
X        /* The 'extra' array contains the extra stuff that is */
X        /* inserted to represent special characters (tabs, and */
X        /* other non-printable stuff.  The order in the 'extra' */
X        /* array is reversed. */
X
X        if ( nextra > 0 )
X            c = extra[--nextra];
X        else {
X            c = (unsigned)(0xff & gchar(&memp));
X            if (inc(&memp) == -1)
X                eof = TRUE;
X            /* when getting a character from the file, we */
X            /* may have to turn it into something else on */
X            /* the way to putting it into 'Nextscreen'. */
X            if ( c == TAB && !P(P_LS) ) {
X                strcpy(extra,"        ");
X                /* tab amount depends on current column */
X                nextra = ((P(P_TS)-1) - (col - coff)%P(P_TS));
X                c = ' ';
X            } else if ( c == NUL && P(P_LS) ) {
X                extra[0] = NUL;
X                nextra = 1;
X                c = '$';
X            } else if ( c != NUL && (n=chars[c].ch_size) > 1 ) {
X                char *p;
X                nextra = 0;
X                p = chars[c].ch_str;
X                /* copy 'ch-str'ing into 'extra' in reverse */
X                while ( n > 1 )
X                    extra[nextra++] = p[--n];
X                c = p[0];
X            }
X        }
X
X        if ( c == NUL ) {
X            row++;
X            /* get pointer to start of next row */
X            nextrow = &Nextscreen[row*Columns];
X            /* blank out the rest of this row */
X            while ( screenp != nextrow )
X                *screenp++ = ' ';
X            col = 0;
X            break;
X        }
X
X        if ( col >= Columns ) {
X            row++;
X            col = 0;
X        }
X        /* store the character in Nextscreen */
X        *screenp++ = c;
X        col++;
X    }
X    return ((row - Cline_row) == Cline_size);
X}
X
X/*
X * lnexttoscreen
X *
X * Like nexttoscreen() but only for the cursor line.
X */
Xstatic void
Xlnexttoscreen()
X{
X    register char    *np = Nextscreen + (Cline_row * Columns);
X    register char    *rp = Realscreen + (Cline_row * Columns);
X    register char    *endline;
X    register int    row, col;
X    int    gorow = -1, gocol = -1;
X
X    if (anyinput()) {
X        need_redraw = TRUE;
X        return;
X    }
X
X    endline = np + (Cline_size * Columns);
X
X    row = Cline_row;
X    col = 0;
X
X    CUROFF;        /* disable cursor */
X
X    for ( ; np < endline ; np++,rp++ ) {
X        /* If desired screen (contents of Nextscreen) does not */
X        /* match what's really there, put it there. */
X        if ( *np != *rp ) {
X            /* if we are positioned at the right place, */
X            /* we don't have to use windgoto(). */
X            if (gocol != col || gorow != row) {
X                /*
X                 * If we're just off by one, don't send
X                 * an entire esc. seq. (this happens a lot!)
X                 */
X                if (gorow == row && gocol+1 == col) {
X                    outchar(*(np-1));
X                    gocol++;
X                } else
X                    windgoto(gorow=row,gocol=col);
X            }
X            outchar(*rp = *np);
X            gocol++;
X        }
X        if ( ++col >= Columns ) {
X            col = 0;
X            row++;
X        }
X    }
X    CURON;        /* enable cursor again */
X}
X
Xstatic char *
Xmkline(n)
Xregister int    n;
X{
X    static    char    lbuf[9];
X    register int    i = 2;
X
X    strcpy(lbuf, "        ");
X
X    lbuf[i++] = (n % 10) + '0';
X    n /= 10;
X    if (n != 0) {
X        lbuf[i++] = (n % 10) + '0';
X        n /= 10;
X    }
X    if (n != 0) {
X        lbuf[i++] = (n % 10) + '0';
X        n /= 10;
X    }
X    if (n != 0) {
X        lbuf[i++] = (n % 10) + '0';
X        n /= 10;
X    }
X    if (n != 0) {
X        lbuf[i++] = (n % 10) + '0';
X        n /= 10;
X    }
X    return lbuf;
X}
X
X/*
X * updateline() - update the line the cursor is on
X *
X * Updateline() is called after changes that only affect the line that
X * the cursor is on. This improves performance tremendously for normal
X * insert mode operation. The only thing we have to watch for is when
X * the cursor line grows or shrinks around a row boundary. This means
X * we have to repaint other parts of the screen appropriately. If
X * lfiletonext() returns FALSE, the size of the cursor line (in rows)
X * has changed and we have to call updatescreen() to do a complete job.
X */
Xvoid
Xupdateline()
X{
X    if (!lfiletonext())
X        updatescreen();    /* bag it, do the whole screen */
X    else
X        lnexttoscreen();
X}
X
Xvoid
Xupdatescreen()
X{
X    extern    bool_t    interactive;
X
X    if (interactive) {
X        filetonext();
X        nexttoscreen();
X    }
X}
X
X/*
X * prt_line() - print the given line
X */
Xvoid
Xprt_line(s)
Xchar    *s;
X{
X    register int    si = 0;
X    register int    c;
X    register int    col = 0;
X
X    char    extra[16];
X    int    nextra = 0;
X    int    n;
X
X    for (;;) {
X
X        if ( nextra > 0 )
X            c = extra[--nextra];
X        else {
X            c = s[si++];
X            if ( c == TAB && !P(P_LS) ) {
X                strcpy(extra, "        ");
X                /* tab amount depends on current column */
X                nextra = (P(P_TS) - 1) - col%P(P_TS);
X                c = ' ';
X            } else if ( c == NUL && P(P_LS) ) {
X                extra[0] = NUL;
X                nextra = 1;
X                c = '$';
X            } else if ( c != NUL && (n=chars[c].ch_size) > 1 ) {
X                char    *p;
X
X                nextra = 0;
X                p = chars[c].ch_str;
X                /* copy 'ch-str'ing into 'extra' in reverse */
X                while ( n > 1 )
X                    extra[nextra++] = p[--n];
X                c = p[0];
X            }
X        }
X
X        if ( c == NUL )
X            break;
X
X        outchar(c);
X        col++;
X    }
X}
X
Xvoid
Xscreenclear()
X{
X    register char    *rp, *np;
X    register char    *end;
X
X    CLS;        /* clear the display */
X
X    rp  = Realscreen;
X    end = Realscreen + Rows * Columns;
X    np  = Nextscreen;
X
X    /* blank out the stored screens */
X    while (rp != end)
X        *rp++ = *np++ = ' ';
X}
X
Xvoid
Xcursupdate()
X{
X    register LPTR    *p;
X    register int    icnt, c, nlines;
X    register int    i;
X    int    didinc;
X
X    if (bufempty()) {        /* special case - file is empty */
X        *Topchar  = *Filemem;
X        *Curschar = *Filemem;
X    } else if ( LINEOF(Curschar) < LINEOF(Topchar) ) {
X        nlines = cntllines(Curschar,Topchar);
X        /* if the cursor is above the top of */
X        /* the screen, put it at the top of the screen.. */
X        *Topchar = *Curschar;
X        Topchar->index = 0;
X        /* ... and, if we weren't very close to begin with, */
X        /* we scroll so that the line is close to the middle. */
X        if ( nlines > Rows/3 ) {
X            for (i=0, p = Topchar; i < Rows/3 ;i++, *Topchar = *p)
X                if ((p = prevline(p)) == NULL)
X                    break;
X        } else
X            s_ins(0, nlines-1);
X        updatescreen();
X    }
X    else if (LINEOF(Curschar) >= LINEOF(Botchar)) {
X        nlines = cntllines(Botchar,Curschar);
X        /* If the cursor is off the bottom of the screen, */
X        /* put it at the top of the screen.. */
X        /* ... and back up */
X        if ( nlines > Rows/3 ) {
X            p = Curschar;
X            for (i=0; i < (2*Rows)/3 ;i++)
X                if ((p = prevline(p)) == NULL)
X                    break;
X            *Topchar = *p;
X        } else {
X            scrollup(nlines);
X        }
X        updatescreen();
X    }
X
X    Cursrow = Curscol = Cursvcol = 0;
X    for ( p=Topchar; p->linep != Curschar->linep ;p = nextline(p) )
X        Cursrow += plines(p);
X
X    Cline_row = Cursrow;
X    Cline_size = plines(p);
X
X    if (P(P_NU))
X        Curscol = 8;
X
X    for (i=0; i <= Curschar->index ;i++) {
X        c = Curschar->linep->s[i];
X        /* A tab gets expanded, depending on the current column */
X        if ( c == TAB && !P(P_LS) )
X            icnt = P(P_TS) - (Cursvcol % P(P_TS));
X        else
X            icnt = chars[(unsigned)(c & 0xff)].ch_size;
X        Curscol += icnt;
X        Cursvcol += icnt;
X        if ( Curscol >= Columns ) {
X            Curscol -= Columns;
X            Cursrow++;
X            didinc = TRUE;
X        }
X        else
X            didinc = FALSE;
X    }
X    if (didinc)
X        Cursrow--;
X
X    if (c == TAB && State == NORMAL && !P(P_LS)) {
X        Curscol--;
X        Cursvcol--;
X    } else {
X        Curscol -= icnt;
X        Cursvcol -= icnt;
X    }
X    if (Curscol < 0)
X        Curscol += Columns;
X
X    if (set_want_col) {
X        Curswant = Cursvcol;
X        set_want_col = FALSE;
X    }
X}
X
X/*
X * The rest of the routines in this file perform screen manipulations.
X * The given operation is performed physically on the screen. The
X * corresponding change is also made to the internal screen image.
X * In this way, the editor anticipates the effect of editing changes
X * on the appearance of the screen. That way, when we call screenupdate
X * a complete redraw isn't usually necessary. Another advantage is that
X * we can keep adding code to anticipate screen changes, and in the
X * meantime, everything still works.
X */
X
X/*
X * s_ins(row, nlines) - insert 'nlines' lines at 'row'
X */
Xvoid
Xs_ins(row, nlines)
Xint    row;
Xint    nlines;
X{
X    register char    *s, *d;        /* src & dest for block copy */
X    register char    *e;        /* end point for copy */
X    register int    i;
X
X    if ( ! CANIL )        /* can't do it */
X        return;
X
X    /*
X     * It "looks" better if we do all the inserts at once
X     */
X    SAVCUR;            /* save position */
X    windgoto(row, 0);
X
X    CRTIL( row, nlines );
X
X    windgoto(Rows-1, 0);    /* delete any garbage that may have */
X    CLEOL;            /* been shifted to the bottom line */
X    RESCUR;            /* restore the cursor position */
X
X    /*
X     * Now do a block move to update the internal screen image
X     */
X    d = Realscreen + (Columns * (Rows - 1)) - 1;
X    s = d - (Columns * nlines);
X    e = Realscreen + (Columns * row);
X
X    while (s >= e)
X        *d-- = *s--;
X
X    /*
X     * Clear the inserted lines
X     */
X    s = Realscreen + (row * Columns);
X    e = s + (nlines * Columns);
X    while (s < e)
X        *s++ = ' ';
X}
X
X/*
X * s_del(row, nlines) - delete 'nlines' lines at 'row'
X */
Xvoid
Xs_del(row, nlines)
Xint    row;
Xint    nlines;
X{
X    register char    *s, *d, *e;
X    register int    i;
X
X#ifndef BIOS
X    if ( ! CANDL ) return;        /* can't do it */
X#endif
X
X    /* delete the lines */
X    SAVCUR;                /* save position */
X
X    windgoto (Rows-1, 0);        /* go to status line */
X    CLEOL;                /* Clear it */
X    windgoto (row, 0);        /* Go to 1st line-to-del */
X    CRTDL( row, nlines );        /* Delete the lines */
X    RESCUR;                /* Restore the cursor */
X
X    /*
X     * do a block move to update the internal image
X     */
X    d = Realscreen + (row * Columns);
X    s = d + (nlines * Columns);
X    e = Realscreen + ((Rows - 1) * Columns);
X
X    while (s < e)
X        *d++ = *s++;
X
X    while (d < e)        /* clear the lines at the bottom */
X        *d++ = ' ';
X}
!EOR!