dol.c

早期freebsd实现

		}
		if (ffile == 0)
		    stderror(ERR_DOLZERO);
		fixDolMod();
		setDolp(ffile);
		goto eatbrac;
	    }
	    if (bitset)
		stderror(ERR_DOLQUEST);
	    vp = adrof(STRargv);
	    if (vp == 0) {
		vp = &nulargv;
		goto eatmod;
	    }
	    break;
	}
	if (!alnum(c))
	    stderror(ERR_VARALNUM);
	for (;;) {
	    *np++ = c;
	    c = DgetC(0);
	    if (!alnum(c))
		break;
	    if (np >= &name[MAXVARLEN])
		stderror(ERR_VARTOOLONG);
	}
	*np++ = 0;
	unDredc(c);
	vp = adrof(name);
    }
    if (bitset) {
	dolp = (vp || getenv(short2str(name))) ? STR1 : STR0;
	goto eatbrac;
    }
    if (vp == 0) {
	np = str2short(getenv(short2str(name)));
	if (np) {
	    fixDolMod();
	    setDolp(np);
	    goto eatbrac;
	}
	udvar(name);
	/* NOTREACHED */
    }
    c = DgetC(0);
    upb = blklen(vp->vec);
    if (dimen == 0 && subscr == 0 && c == '[') {
	np = name;
	for (;;) {
	    c = DgetC(DODOL);	/* Allow $ expand within [ ] */
	    if (c == ']')
		break;
	    if (c == '\n' || c == DEOF)
		stderror(ERR_INCBR);
	    if (np >= &name[sizeof(name) / sizeof(Char) - 2])
		stderror(ERR_VARTOOLONG);
	    *np++ = c;
	}
	*np = 0, np = name;
	if (dolp || dolcnt)	/* $ exp must end before ] */
	    stderror(ERR_EXPORD);
	if (!*np)
	    stderror(ERR_SYNTAX);
	if (Isdigit(*np)) {
	    int     i;

	    for (i = 0; Isdigit(*np); i = i * 10 + *np++ - '0')
		continue;
	    if ((i < 0 || i > upb) && !any("-*", *np)) {
		dolerror(vp->v_name);
		return;
	    }
	    lwb = i;
	    if (!*np)
		upb = lwb, np = STRstar;
	}
	if (*np == '*')
	    np++;
	else if (*np != '-')
	    stderror(ERR_MISSING, '-');
	else {
	    register int i = upb;

	    np++;
	    if (Isdigit(*np)) {
		i = 0;
		while (Isdigit(*np))
		    i = i * 10 + *np++ - '0';
		if (i < 0 || i > upb) {
		    dolerror(vp->v_name);
		    return;
		}
	    }
	    if (i < lwb)
		upb = lwb - 1;
	    else
		upb = i;
	}
	if (lwb == 0) {
	    if (upb != 0) {
		dolerror(vp->v_name);
		return;
	    }
	    upb = -1;
	}
	if (*np)
	    stderror(ERR_SYNTAX);
    }
    else {
	if (subscr > 0)
	    if (subscr > upb)
		lwb = 1, upb = 0;
	    else
		lwb = upb = subscr;
	unDredc(c);
    }
    if (dimen) {
	Char   *cp = putn(upb - lwb + 1);

	addla(cp);
	xfree((ptr_t) cp);
    }
    else {
eatmod:
	fixDolMod();
	dolnxt = &vp->vec[lwb - 1];
	dolcnt = upb - lwb + 1;
    }
eatbrac:
    if (sc == '{') {
	c = Dredc();
	if (c != '}')
	    stderror(ERR_MISSING, '}');
    }
}

static void
fixDolMod()
{
    register int c;

    c = DgetC(0);
    if (c == ':') {
	do {
	    c = DgetC(0), dolmcnt = 1, dolwcnt = 1;
	    if (c == 'g' || c == 'a') {
		if (c == 'g')
		    dolmcnt = 10000;
		else
		    dolwcnt = 10000;
		c = DgetC(0);
	    }
	    if ((c == 'g' && dolmcnt != 10000) || 
		(c == 'a' && dolwcnt != 10000)) {
		if (c == 'g')
		    dolmcnt = 10000;
		else
		    dolwcnt = 10000;
		c = DgetC(0); 
	    }

	    if (c == 's') {	/* [eichin:19910926.0755EST] */
		int delimcnt = 2;
		int delim = DgetC(0);
		dolmod[dolnmod++] = c;
		dolmod[dolnmod++] = delim;
		
		if (!delim || letter(delim)
		    || Isdigit(delim) || any(" \t\n", delim)) {
		    seterror(ERR_BADSUBST);
		    break;
		}	
		while ((c = DgetC(0)) != (-1)) {
		    dolmod[dolnmod++] = c;
		    if(c == delim) delimcnt--;
		    if(!delimcnt) break;
		}
		if(delimcnt) {
		    seterror(ERR_BADSUBST);
		    break;
		}
		continue;
	    }
	    if (!any("htrqxes", c))
		stderror(ERR_BADMOD, c);
	    dolmod[dolnmod++] = c;
	    if (c == 'q')
		dolmcnt = 10000;
	}
	while ((c = DgetC(0)) == ':');
	unDredc(c);
    }
    else
	unDredc(c);
}

static void
setDolp(cp)
    register Char *cp;
{
    register Char *dp;
    int i;

    if (dolnmod == 0 || dolmcnt == 0) {
	dolp = cp;
	return;
    }
    dp = cp = Strsave(cp);
    for (i = 0; i < dolnmod; i++) {
	/* handle s// [eichin:19910926.0510EST] */
	if(dolmod[i] == 's') {
	    int delim;
	    Char *lhsub, *rhsub, *np;
	    size_t lhlen = 0, rhlen = 0;
	    int didmod = 0;
		
	    delim = dolmod[++i];
	    if (!delim || letter(delim)
		|| Isdigit(delim) || any(" \t\n", delim)) {
		seterror(ERR_BADSUBST);
		break;
	    }
	    lhsub = &dolmod[++i];
	    while(dolmod[i] != delim && dolmod[++i]) {
		lhlen++;
	    }
	    dolmod[i] = 0;
	    rhsub = &dolmod[++i];
	    while(dolmod[i] != delim && dolmod[++i]) {
		rhlen++;
	    }
	    dolmod[i] = 0;

	    do {
		dp = Strstr(cp, lhsub);
		if (dp) {
		    np = (Char *) xmalloc((size_t)
					  ((Strlen(cp) + 1 - lhlen + rhlen) *
					  sizeof(Char)));
		    (void) Strncpy(np, cp, dp - cp);
		    (void) Strcpy(np + (dp - cp), rhsub);
		    (void) Strcpy(np + (dp - cp) + rhlen, dp + lhlen);

		    xfree((ptr_t) cp);
		    dp = cp = np;
		    didmod = 1;
		} else {
		    /* should this do a seterror? */
		    break;
		}
	    }
	    while (dolwcnt == 10000);
	    /*
	     * restore dolmod for additional words
	     */
	    dolmod[i] = rhsub[-1] = delim;
	    if (didmod)
		dolmcnt--;
	    else
		break;
        } else {
	    int didmod = 0;

	    do {
		if ((dp = domod(cp, dolmod[i]))) {
		    didmod = 1;
		    if (Strcmp(cp, dp) == 0) {
			xfree((ptr_t) cp);
			cp = dp;
			break;
		    }
		    else {
			xfree((ptr_t) cp);
			cp = dp;
		    }
		}
		else
		    break;
	    }
	    while (dolwcnt == 10000);
	    dp = cp;
	    if (didmod)
		dolmcnt--;
	    else
		break;
	}
    }

    if (dp) {
	addla(dp);
	xfree((ptr_t) dp);
    }
    else
	addla(cp);

    dolp = STRNULL;
    if (seterr)
	stderror(ERR_OLD);
}

static void
unDredc(c)
    int     c;
{

    Dpeekrd = c;
}

static int
Dredc()
{
    register int c;

    if ((c = Dpeekrd) != '\0') {
	Dpeekrd = 0;
	return (c);
    }
    if (Dcp && (c = *Dcp++))
	return (c & (QUOTE | TRIM));
    if (*Dvp == 0) {
	Dcp = 0;
	return (DEOF);
    }
    Dcp = *Dvp++;
    return (' ');
}

static void
Dtestq(c)
    register int c;
{

    if (cmap(c, QUOTES))
	gflag = 1;
}

/*
 * Form a shell temporary file (in unit 0) from the words
 * of the shell input up to EOF or a line the same as "term".
 * Unit 0 should have been closed before this call.
 */
void
/*ARGSUSED*/
heredoc(term)
    Char *term;
{
    register int c;
    Char   *Dv[2];
    Char    obuf[BUFSIZ], lbuf[BUFSIZ], mbuf[BUFSIZ];
    int     ocnt, lcnt, mcnt;
    register Char *lbp, *obp, *mbp;
    Char  **vp;
    bool    quoted;
    char   *tmp;

    if (creat(tmp = short2str(shtemp), 0600) < 0)
	stderror(ERR_SYSTEM, tmp, strerror(errno));
    (void) close(0);
    if (open(tmp, O_RDWR) < 0) {
	int     oerrno = errno;

	(void) unlink(tmp);
	errno = oerrno;
	stderror(ERR_SYSTEM, tmp, strerror(errno));
    }
    (void) unlink(tmp);		/* 0 0 inode! */
    Dv[0] = term;
    Dv[1] = NULL;
    gflag = 0;
    trim(Dv);
    rscan(Dv, Dtestq);
    quoted = gflag;
    ocnt = BUFSIZ;
    obp = obuf;
    for (;;) {
	/*
	 * Read up a line
	 */
	lbp = lbuf;
	lcnt = BUFSIZ - 4;
	for (;;) {
	    c = readc(1);	/* 1 -> Want EOF returns */
	    if (c < 0 || c == '\n')
		break;
	    if ((c &= TRIM) != '\0') {
		*lbp++ = c;
		if (--lcnt < 0) {
		    setname("<<");
		    stderror(ERR_NAME | ERR_OVERFLOW);
		}
	    }
	}
	*lbp = 0;

	/*
	 * Check for EOF or compare to terminator -- before expansion
	 */
	if (c < 0 || eq(lbuf, term)) {
	    (void) write(0, short2str(obuf), (size_t) (BUFSIZ - ocnt));
	    (void) lseek(0, 0l, L_SET);
	    return;
	}

	/*
	 * If term was quoted or -n just pass it on
	 */
	if (quoted || noexec) {
	    *lbp++ = '\n';
	    *lbp = 0;
	    for (lbp = lbuf; (c = *lbp++) != '\0';) {
		*obp++ = c;
		if (--ocnt == 0) {
		    (void) write(0, short2str(obuf), BUFSIZ);
		    obp = obuf;
		    ocnt = BUFSIZ;
		}
	    }
	    continue;
	}

	/*
	 * Term wasn't quoted so variable and then command expand the input
	 * line
	 */
	Dcp = lbuf;
	Dvp = Dv + 1;
	mbp = mbuf;
	mcnt = BUFSIZ - 4;
	for (;;) {
	    c = DgetC(DODOL);
	    if (c == DEOF)
		break;
	    if ((c &= TRIM) == 0)
		continue;
	    /* \ quotes \ $ ` here */
	    if (c == '\\') {
		c = DgetC(0);
		if (!any("$\\`", c))
		    unDgetC(c | QUOTE), c = '\\';
		else
		    c |= QUOTE;
	    }
	    *mbp++ = c;
	    if (--mcnt == 0) {
		setname("<<");
		stderror(ERR_NAME | ERR_OVERFLOW);
	    }
	}
	*mbp++ = 0;

	/*
	 * If any ` in line do command substitution
	 */
	mbp = mbuf;
	if (any(short2str(mbp), '`')) {
	    /*
	     * 1 arg to dobackp causes substitution to be literal. Words are
	     * broken only at newlines so that all blanks and tabs are
	     * preserved.  Blank lines (null words) are not discarded.
	     */
	    vp = dobackp(mbuf, 1);
	}
	else
	    /* Setup trivial vector similar to return of dobackp */
	    Dv[0] = mbp, Dv[1] = NULL, vp = Dv;

	/*
	 * Resurrect the words from the command substitution each separated by
	 * a newline.  Note that the last newline of a command substitution
	 * will have been discarded, but we put a newline after the last word
	 * because this represents the newline after the last input line!
	 */
	for (; *vp; vp++) {
	    for (mbp = *vp; *mbp; mbp++) {
		*obp++ = *mbp & TRIM;
		if (--ocnt == 0) {
		    (void) write(0, short2str(obuf), BUFSIZ);
		    obp = obuf;
		    ocnt = BUFSIZ;
		}
	    }
	    *obp++ = '\n';
	    if (--ocnt == 0) {
		(void) write(0, short2str(obuf), BUFSIZ);
		obp = obuf;
		ocnt = BUFSIZ;
	    }
	}
	if (pargv)
	    blkfree(pargv), pargv = 0;
    }
}