auto import from //depot/cupcake/@135843
diff --git a/sh/expand.c b/sh/expand.c
new file mode 100644
index 0000000..d3462fc
--- /dev/null
+++ b/sh/expand.c
@@ -0,0 +1,1559 @@
+/* $NetBSD: expand.c,v 1.68.2.2 2005/04/07 11:37:39 tron Exp $ */
+
+/*-
+ * Copyright (c) 1991, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Kenneth Almquist.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+#ifndef lint
+#if 0
+static char sccsid[] = "@(#)expand.c 8.5 (Berkeley) 5/15/95";
+#else
+__RCSID("$NetBSD: expand.c,v 1.68.2.2 2005/04/07 11:37:39 tron Exp $");
+#endif
+#endif /* not lint */
+
+#include <sys/types.h>
+#include <sys/time.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <dirent.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+/*
+ * Routines to expand arguments to commands. We have to deal with
+ * backquotes, shell variables, and file metacharacters.
+ */
+
+#include "shell.h"
+#include "main.h"
+#include "nodes.h"
+#include "eval.h"
+#include "expand.h"
+#include "syntax.h"
+#include "parser.h"
+#include "jobs.h"
+#include "options.h"
+#include "var.h"
+#include "input.h"
+#include "output.h"
+#include "memalloc.h"
+#include "error.h"
+#include "mystring.h"
+#include "show.h"
+
+/*
+ * Structure specifying which parts of the string should be searched
+ * for IFS characters.
+ */
+
+struct ifsregion {
+ struct ifsregion *next; /* next region in list */
+ int begoff; /* offset of start of region */
+ int endoff; /* offset of end of region */
+ int inquotes; /* search for nul bytes only */
+};
+
+
+char *expdest; /* output of current string */
+struct nodelist *argbackq; /* list of back quote expressions */
+struct ifsregion ifsfirst; /* first struct in list of ifs regions */
+struct ifsregion *ifslastp; /* last struct in list */
+struct arglist exparg; /* holds expanded arg list */
+
+STATIC void argstr(char *, int);
+STATIC char *exptilde(char *, int);
+STATIC void expbackq(union node *, int, int);
+STATIC int subevalvar(char *, char *, int, int, int, int);
+STATIC char *evalvar(char *, int);
+STATIC int varisset(char *, int);
+STATIC void varvalue(char *, int, int, int);
+STATIC void recordregion(int, int, int);
+STATIC void removerecordregions(int);
+STATIC void ifsbreakup(char *, struct arglist *);
+STATIC void ifsfree(void);
+STATIC void expandmeta(struct strlist *, int);
+STATIC void expmeta(char *, char *);
+STATIC void addfname(char *);
+STATIC struct strlist *expsort(struct strlist *);
+STATIC struct strlist *msort(struct strlist *, int);
+STATIC int pmatch(char *, char *, int);
+STATIC char *cvtnum(int, char *);
+
+/*
+ * Expand shell variables and backquotes inside a here document.
+ */
+
+void
+expandhere(union node *arg, int fd)
+{
+ herefd = fd;
+ expandarg(arg, (struct arglist *)NULL, 0);
+ xwrite(fd, stackblock(), expdest - stackblock());
+}
+
+
+/*
+ * Perform variable substitution and command substitution on an argument,
+ * placing the resulting list of arguments in arglist. If EXP_FULL is true,
+ * perform splitting and file name expansion. When arglist is NULL, perform
+ * here document expansion.
+ */
+
+void
+expandarg(union node *arg, struct arglist *arglist, int flag)
+{
+ struct strlist *sp;
+ char *p;
+
+ argbackq = arg->narg.backquote;
+ STARTSTACKSTR(expdest);
+ ifsfirst.next = NULL;
+ ifslastp = NULL;
+ argstr(arg->narg.text, flag);
+ if (arglist == NULL) {
+ return; /* here document expanded */
+ }
+ STPUTC('\0', expdest);
+ p = grabstackstr(expdest);
+ exparg.lastp = &exparg.list;
+ /*
+ * TODO - EXP_REDIR
+ */
+ if (flag & EXP_FULL) {
+ ifsbreakup(p, &exparg);
+ *exparg.lastp = NULL;
+ exparg.lastp = &exparg.list;
+ expandmeta(exparg.list, flag);
+ } else {
+ if (flag & EXP_REDIR) /*XXX - for now, just remove escapes */
+ rmescapes(p);
+ sp = (struct strlist *)stalloc(sizeof (struct strlist));
+ sp->text = p;
+ *exparg.lastp = sp;
+ exparg.lastp = &sp->next;
+ }
+ ifsfree();
+ *exparg.lastp = NULL;
+ if (exparg.list) {
+ *arglist->lastp = exparg.list;
+ arglist->lastp = exparg.lastp;
+ }
+}
+
+
+
+/*
+ * Perform variable and command substitution.
+ * If EXP_FULL is set, output CTLESC characters to allow for further processing.
+ * Otherwise treat $@ like $* since no splitting will be performed.
+ */
+
+STATIC void
+argstr(char *p, int flag)
+{
+ char c;
+ int quotes = flag & (EXP_FULL | EXP_CASE); /* do CTLESC */
+ int firsteq = 1;
+ const char *ifs = 0;
+ int ifs_split = EXP_IFS_SPLIT;
+
+ if (flag & EXP_IFS_SPLIT)
+ ifs = ifsset() ? ifsval() : " \t\n";
+
+ if (*p == '~' && (flag & (EXP_TILDE | EXP_VARTILDE)))
+ p = exptilde(p, flag);
+ for (;;) {
+ switch (c = *p++) {
+ case '\0':
+ case CTLENDVAR: /* end of expanding yyy in ${xxx-yyy} */
+ return;
+ case CTLQUOTEMARK:
+ /* "$@" syntax adherence hack */
+ if (p[0] == CTLVAR && p[2] == '@' && p[3] == '=')
+ break;
+ if ((flag & EXP_FULL) != 0)
+ STPUTC(c, expdest);
+ ifs_split = 0;
+ break;
+ case CTLQUOTEEND:
+ ifs_split = EXP_IFS_SPLIT;
+ break;
+ case CTLESC:
+ if (quotes)
+ STPUTC(c, expdest);
+ c = *p++;
+ STPUTC(c, expdest);
+ break;
+ case CTLVAR:
+ p = evalvar(p, (flag & ~EXP_IFS_SPLIT) | (flag & ifs_split));
+ break;
+ case CTLBACKQ:
+ case CTLBACKQ|CTLQUOTE:
+ expbackq(argbackq->n, c & CTLQUOTE, flag);
+ argbackq = argbackq->next;
+ break;
+ case CTLENDARI:
+ expari(flag);
+ break;
+ case ':':
+ case '=':
+ /*
+ * sort of a hack - expand tildes in variable
+ * assignments (after the first '=' and after ':'s).
+ */
+ STPUTC(c, expdest);
+ if (flag & EXP_VARTILDE && *p == '~') {
+ if (c == '=') {
+ if (firsteq)
+ firsteq = 0;
+ else
+ break;
+ }
+ p = exptilde(p, flag);
+ }
+ break;
+ default:
+ STPUTC(c, expdest);
+ if (flag & EXP_IFS_SPLIT & ifs_split && strchr(ifs, c) != NULL) {
+ /* We need to get the output split here... */
+ recordregion(expdest - stackblock() - 1,
+ expdest - stackblock(), 0);
+ }
+ break;
+ }
+ }
+}
+
+STATIC char *
+exptilde(char *p, int flag)
+{
+ char c, *startp = p;
+ const char *home;
+ int quotes = flag & (EXP_FULL | EXP_CASE);
+
+ while ((c = *p) != '\0') {
+ switch(c) {
+ case CTLESC:
+ return (startp);
+ case CTLQUOTEMARK:
+ return (startp);
+ case ':':
+ if (flag & EXP_VARTILDE)
+ goto done;
+ break;
+ case '/':
+ goto done;
+ }
+ p++;
+ }
+done:
+ *p = '\0';
+ if (*(startp+1) == '\0') {
+ if ((home = lookupvar("HOME")) == NULL)
+ goto lose;
+ } else
+ goto lose;
+ if (*home == '\0')
+ goto lose;
+ *p = c;
+ while ((c = *home++) != '\0') {
+ if (quotes && SQSYNTAX[(int)c] == CCTL)
+ STPUTC(CTLESC, expdest);
+ STPUTC(c, expdest);
+ }
+ return (p);
+lose:
+ *p = c;
+ return (startp);
+}
+
+
+STATIC void
+removerecordregions(int endoff)
+{
+ if (ifslastp == NULL)
+ return;
+
+ if (ifsfirst.endoff > endoff) {
+ while (ifsfirst.next != NULL) {
+ struct ifsregion *ifsp;
+ INTOFF;
+ ifsp = ifsfirst.next->next;
+ ckfree(ifsfirst.next);
+ ifsfirst.next = ifsp;
+ INTON;
+ }
+ if (ifsfirst.begoff > endoff)
+ ifslastp = NULL;
+ else {
+ ifslastp = &ifsfirst;
+ ifsfirst.endoff = endoff;
+ }
+ return;
+ }
+
+ ifslastp = &ifsfirst;
+ while (ifslastp->next && ifslastp->next->begoff < endoff)
+ ifslastp=ifslastp->next;
+ while (ifslastp->next != NULL) {
+ struct ifsregion *ifsp;
+ INTOFF;
+ ifsp = ifslastp->next->next;
+ ckfree(ifslastp->next);
+ ifslastp->next = ifsp;
+ INTON;
+ }
+ if (ifslastp->endoff > endoff)
+ ifslastp->endoff = endoff;
+}
+
+
+/*
+ * Expand arithmetic expression. Backup to start of expression,
+ * evaluate, place result in (backed up) result, adjust string position.
+ */
+void
+expari(int flag)
+{
+ char *p, *start;
+ int result;
+ int begoff;
+ int quotes = flag & (EXP_FULL | EXP_CASE);
+ int quoted;
+
+ /* ifsfree(); */
+
+ /*
+ * This routine is slightly over-complicated for
+ * efficiency. First we make sure there is
+ * enough space for the result, which may be bigger
+ * than the expression if we add exponentation. Next we
+ * scan backwards looking for the start of arithmetic. If the
+ * next previous character is a CTLESC character, then we
+ * have to rescan starting from the beginning since CTLESC
+ * characters have to be processed left to right.
+ */
+#if INT_MAX / 1000000000 >= 10 || INT_MIN / 1000000000 <= -10
+#error "integers with more than 10 digits are not supported"
+#endif
+ CHECKSTRSPACE(12 - 2, expdest);
+ USTPUTC('\0', expdest);
+ start = stackblock();
+ p = expdest - 1;
+ while (*p != CTLARI && p >= start)
+ --p;
+ if (*p != CTLARI)
+ error("missing CTLARI (shouldn't happen)");
+ if (p > start && *(p-1) == CTLESC)
+ for (p = start; *p != CTLARI; p++)
+ if (*p == CTLESC)
+ p++;
+
+ if (p[1] == '"')
+ quoted=1;
+ else
+ quoted=0;
+ begoff = p - start;
+ removerecordregions(begoff);
+ if (quotes)
+ rmescapes(p+2);
+ result = arith(p+2);
+ fmtstr(p, 12, "%d", result);
+
+ while (*p++)
+ ;
+
+ if (quoted == 0)
+ recordregion(begoff, p - 1 - start, 0);
+ result = expdest - p + 1;
+ STADJUST(-result, expdest);
+}
+
+
+/*
+ * Expand stuff in backwards quotes.
+ */
+
+STATIC void
+expbackq(union node *cmd, int quoted, int flag)
+{
+ struct backcmd in;
+ int i;
+ char buf[128];
+ char *p;
+ char *dest = expdest;
+ struct ifsregion saveifs, *savelastp;
+ struct nodelist *saveargbackq;
+ char lastc;
+ int startloc = dest - stackblock();
+ char const *syntax = quoted? DQSYNTAX : BASESYNTAX;
+ int saveherefd;
+ int quotes = flag & (EXP_FULL | EXP_CASE);
+
+ INTOFF;
+ saveifs = ifsfirst;
+ savelastp = ifslastp;
+ saveargbackq = argbackq;
+ saveherefd = herefd;
+ herefd = -1;
+ p = grabstackstr(dest);
+ evalbackcmd(cmd, &in);
+ ungrabstackstr(p, dest);
+ ifsfirst = saveifs;
+ ifslastp = savelastp;
+ argbackq = saveargbackq;
+ herefd = saveherefd;
+
+ p = in.buf;
+ lastc = '\0';
+ for (;;) {
+ if (--in.nleft < 0) {
+ if (in.fd < 0)
+ break;
+ while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR);
+ TRACE(("expbackq: read returns %d\n", i));
+ if (i <= 0)
+ break;
+ p = buf;
+ in.nleft = i - 1;
+ }
+ lastc = *p++;
+ if (lastc != '\0') {
+ if (quotes && syntax[(int)lastc] == CCTL)
+ STPUTC(CTLESC, dest);
+ STPUTC(lastc, dest);
+ }
+ }
+
+ /* Eat all trailing newlines */
+ p = stackblock() + startloc;
+ while (dest > p && dest[-1] == '\n')
+ STUNPUTC(dest);
+
+ if (in.fd >= 0)
+ close(in.fd);
+ if (in.buf)
+ ckfree(in.buf);
+ if (in.jp)
+ back_exitstatus = waitforjob(in.jp);
+ if (quoted == 0)
+ recordregion(startloc, dest - stackblock(), 0);
+ TRACE(("evalbackq: size=%d: \"%.*s\"\n",
+ (dest - stackblock()) - startloc,
+ (dest - stackblock()) - startloc,
+ stackblock() + startloc));
+ expdest = dest;
+ INTON;
+}
+
+
+
+STATIC int
+subevalvar(char *p, char *str, int strloc, int subtype, int startloc, int varflags)
+{
+ char *startp;
+ char *loc = NULL;
+ char *q;
+ int c = 0;
+ int saveherefd = herefd;
+ struct nodelist *saveargbackq = argbackq;
+ int amount;
+
+ herefd = -1;
+ argstr(p, 0);
+ STACKSTRNUL(expdest);
+ herefd = saveherefd;
+ argbackq = saveargbackq;
+ startp = stackblock() + startloc;
+ if (str == NULL)
+ str = stackblock() + strloc;
+
+ switch (subtype) {
+ case VSASSIGN:
+ setvar(str, startp, 0);
+ amount = startp - expdest;
+ STADJUST(amount, expdest);
+ varflags &= ~VSNUL;
+ if (c != 0)
+ *loc = c;
+ return 1;
+
+ case VSQUESTION:
+ if (*p != CTLENDVAR) {
+ outfmt(&errout, "%s\n", startp);
+ error((char *)NULL);
+ }
+ error("%.*s: parameter %snot set", p - str - 1,
+ str, (varflags & VSNUL) ? "null or "
+ : nullstr);
+ /* NOTREACHED */
+
+ case VSTRIMLEFT:
+ for (loc = startp; loc < str; loc++) {
+ c = *loc;
+ *loc = '\0';
+ if (patmatch(str, startp, varflags & VSQUOTE))
+ goto recordleft;
+ *loc = c;
+ if ((varflags & VSQUOTE) && *loc == CTLESC)
+ loc++;
+ }
+ return 0;
+
+ case VSTRIMLEFTMAX:
+ for (loc = str - 1; loc >= startp;) {
+ c = *loc;
+ *loc = '\0';
+ if (patmatch(str, startp, varflags & VSQUOTE))
+ goto recordleft;
+ *loc = c;
+ loc--;
+ if ((varflags & VSQUOTE) && loc > startp &&
+ *(loc - 1) == CTLESC) {
+ for (q = startp; q < loc; q++)
+ if (*q == CTLESC)
+ q++;
+ if (q > loc)
+ loc--;
+ }
+ }
+ return 0;
+
+ case VSTRIMRIGHT:
+ for (loc = str - 1; loc >= startp;) {
+ if (patmatch(str, loc, varflags & VSQUOTE))
+ goto recordright;
+ loc--;
+ if ((varflags & VSQUOTE) && loc > startp &&
+ *(loc - 1) == CTLESC) {
+ for (q = startp; q < loc; q++)
+ if (*q == CTLESC)
+ q++;
+ if (q > loc)
+ loc--;
+ }
+ }
+ return 0;
+
+ case VSTRIMRIGHTMAX:
+ for (loc = startp; loc < str - 1; loc++) {
+ if (patmatch(str, loc, varflags & VSQUOTE))
+ goto recordright;
+ if ((varflags & VSQUOTE) && *loc == CTLESC)
+ loc++;
+ }
+ return 0;
+
+ default:
+ abort();
+ }
+
+recordleft:
+ *loc = c;
+ amount = ((str - 1) - (loc - startp)) - expdest;
+ STADJUST(amount, expdest);
+ while (loc != str - 1)
+ *startp++ = *loc++;
+ return 1;
+
+recordright:
+ amount = loc - expdest;
+ STADJUST(amount, expdest);
+ STPUTC('\0', expdest);
+ STADJUST(-1, expdest);
+ return 1;
+}
+
+
+/*
+ * Expand a variable, and return a pointer to the next character in the
+ * input string.
+ */
+
+STATIC char *
+evalvar(char *p, int flag)
+{
+ int subtype;
+ int varflags;
+ char *var;
+ char *val;
+ int patloc;
+ int c;
+ int set;
+ int special;
+ int startloc;
+ int varlen;
+ int apply_ifs;
+ int quotes = flag & (EXP_FULL | EXP_CASE);
+
+ varflags = (unsigned char)*p++;
+ subtype = varflags & VSTYPE;
+ var = p;
+ special = !is_name(*p);
+ p = strchr(p, '=') + 1;
+
+again: /* jump here after setting a variable with ${var=text} */
+ if (special) {
+ set = varisset(var, varflags & VSNUL);
+ val = NULL;
+ } else {
+ val = lookupvar(var);
+ if (val == NULL || ((varflags & VSNUL) && val[0] == '\0')) {
+ val = NULL;
+ set = 0;
+ } else
+ set = 1;
+ }
+
+ varlen = 0;
+ startloc = expdest - stackblock();
+
+ if (!set && uflag) {
+ switch (subtype) {
+ case VSNORMAL:
+ case VSTRIMLEFT:
+ case VSTRIMLEFTMAX:
+ case VSTRIMRIGHT:
+ case VSTRIMRIGHTMAX:
+ case VSLENGTH:
+ error("%.*s: parameter not set", p - var - 1, var);
+ /* NOTREACHED */
+ }
+ }
+
+ if (set && subtype != VSPLUS) {
+ /* insert the value of the variable */
+ if (special) {
+ varvalue(var, varflags & VSQUOTE, subtype, flag);
+ if (subtype == VSLENGTH) {
+ varlen = expdest - stackblock() - startloc;
+ STADJUST(-varlen, expdest);
+ }
+ } else {
+ char const *syntax = (varflags & VSQUOTE) ? DQSYNTAX
+ : BASESYNTAX;
+
+ if (subtype == VSLENGTH) {
+ for (;*val; val++)
+ varlen++;
+ } else {
+ while (*val) {
+ if (quotes && syntax[(int)*val] == CCTL)
+ STPUTC(CTLESC, expdest);
+ STPUTC(*val++, expdest);
+ }
+
+ }
+ }
+ }
+
+
+ apply_ifs = ((varflags & VSQUOTE) == 0 ||
+ (*var == '@' && shellparam.nparam != 1));
+
+ switch (subtype) {
+ case VSLENGTH:
+ expdest = cvtnum(varlen, expdest);
+ break;
+
+ case VSNORMAL:
+ break;
+
+ case VSPLUS:
+ set = !set;
+ /* FALLTHROUGH */
+ case VSMINUS:
+ if (!set) {
+ argstr(p, flag | (apply_ifs ? EXP_IFS_SPLIT : 0));
+ /*
+ * ${x-a b c} doesn't get split, but removing the
+ * 'apply_ifs = 0' apparantly breaks ${1+"$@"}..
+ * ${x-'a b' c} should generate 2 args.
+ */
+ /* We should have marked stuff already */
+ apply_ifs = 0;
+ }
+ break;
+
+ case VSTRIMLEFT:
+ case VSTRIMLEFTMAX:
+ case VSTRIMRIGHT:
+ case VSTRIMRIGHTMAX:
+ if (!set)
+ break;
+ /*
+ * Terminate the string and start recording the pattern
+ * right after it
+ */
+ STPUTC('\0', expdest);
+ patloc = expdest - stackblock();
+ if (subevalvar(p, NULL, patloc, subtype,
+ startloc, varflags) == 0) {
+ int amount = (expdest - stackblock() - patloc) + 1;
+ STADJUST(-amount, expdest);
+ }
+ /* Remove any recorded regions beyond start of variable */
+ removerecordregions(startloc);
+ apply_ifs = 1;
+ break;
+
+ case VSASSIGN:
+ case VSQUESTION:
+ if (set)
+ break;
+ if (subevalvar(p, var, 0, subtype, startloc, varflags)) {
+ varflags &= ~VSNUL;
+ /*
+ * Remove any recorded regions beyond
+ * start of variable
+ */
+ removerecordregions(startloc);
+ goto again;
+ }
+ apply_ifs = 0;
+ break;
+
+ default:
+ abort();
+ }
+
+ if (apply_ifs)
+ recordregion(startloc, expdest - stackblock(),
+ varflags & VSQUOTE);
+
+ if (subtype != VSNORMAL) { /* skip to end of alternative */
+ int nesting = 1;
+ for (;;) {
+ if ((c = *p++) == CTLESC)
+ p++;
+ else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) {
+ if (set)
+ argbackq = argbackq->next;
+ } else if (c == CTLVAR) {
+ if ((*p++ & VSTYPE) != VSNORMAL)
+ nesting++;
+ } else if (c == CTLENDVAR) {
+ if (--nesting == 0)
+ break;
+ }
+ }
+ }
+ return p;
+}
+
+
+
+/*
+ * Test whether a specialized variable is set.
+ */
+
+STATIC int
+varisset(char *name, int nulok)
+{
+ if (*name == '!')
+ return backgndpid != -1;
+ else if (*name == '@' || *name == '*') {
+ if (*shellparam.p == NULL)
+ return 0;
+
+ if (nulok) {
+ char **av;
+
+ for (av = shellparam.p; *av; av++)
+ if (**av != '\0')
+ return 1;
+ return 0;
+ }
+ } else if (is_digit(*name)) {
+ char *ap;
+ int num = atoi(name);
+
+ if (num > shellparam.nparam)
+ return 0;
+
+ if (num == 0)
+ ap = arg0;
+ else
+ ap = shellparam.p[num - 1];
+
+ if (nulok && (ap == NULL || *ap == '\0'))
+ return 0;
+ }
+ return 1;
+}
+
+
+
+/*
+ * Add the value of a specialized variable to the stack string.
+ */
+
+STATIC void
+varvalue(char *name, int quoted, int subtype, int flag)
+{
+ int num;
+ char *p;
+ int i;
+ char sep;
+ char **ap;
+ char const *syntax;
+
+#define STRTODEST(p) \
+ do {\
+ if (flag & (EXP_FULL | EXP_CASE) && subtype != VSLENGTH) { \
+ syntax = quoted? DQSYNTAX : BASESYNTAX; \
+ while (*p) { \
+ if (syntax[(int)*p] == CCTL) \
+ STPUTC(CTLESC, expdest); \
+ STPUTC(*p++, expdest); \
+ } \
+ } else \
+ while (*p) \
+ STPUTC(*p++, expdest); \
+ } while (0)
+
+
+ switch (*name) {
+ case '$':
+ num = rootpid;
+ goto numvar;
+ case '?':
+ num = exitstatus;
+ goto numvar;
+ case '#':
+ num = shellparam.nparam;
+ goto numvar;
+ case '!':
+ num = backgndpid;
+numvar:
+ expdest = cvtnum(num, expdest);
+ break;
+ case '-':
+ for (i = 0; optlist[i].name; i++) {
+ if (optlist[i].val)
+ STPUTC(optlist[i].letter, expdest);
+ }
+ break;
+ case '@':
+ if (flag & EXP_FULL && quoted) {
+ for (ap = shellparam.p ; (p = *ap++) != NULL ; ) {
+ STRTODEST(p);
+ if (*ap)
+ STPUTC('\0', expdest);
+ }
+ break;
+ }
+ /* fall through */
+ case '*':
+ if (ifsset() != 0)
+ sep = ifsval()[0];
+ else
+ sep = ' ';
+ for (ap = shellparam.p ; (p = *ap++) != NULL ; ) {
+ STRTODEST(p);
+ if (*ap && sep)
+ STPUTC(sep, expdest);
+ }
+ break;
+ case '0':
+ p = arg0;
+ STRTODEST(p);
+ break;
+ default:
+ if (is_digit(*name)) {
+ num = atoi(name);
+ if (num > 0 && num <= shellparam.nparam) {
+ p = shellparam.p[num - 1];
+ STRTODEST(p);
+ }
+ }
+ break;
+ }
+}
+
+
+
+/*
+ * Record the fact that we have to scan this region of the
+ * string for IFS characters.
+ */
+
+STATIC void
+recordregion(int start, int end, int inquotes)
+{
+ struct ifsregion *ifsp;
+
+ if (ifslastp == NULL) {
+ ifsp = &ifsfirst;
+ } else {
+ if (ifslastp->endoff == start
+ && ifslastp->inquotes == inquotes) {
+ /* extend previous area */
+ ifslastp->endoff = end;
+ return;
+ }
+ ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion));
+ ifslastp->next = ifsp;
+ }
+ ifslastp = ifsp;
+ ifslastp->next = NULL;
+ ifslastp->begoff = start;
+ ifslastp->endoff = end;
+ ifslastp->inquotes = inquotes;
+}
+
+
+
+/*
+ * Break the argument string into pieces based upon IFS and add the
+ * strings to the argument list. The regions of the string to be
+ * searched for IFS characters have been stored by recordregion.
+ */
+STATIC void
+ifsbreakup(char *string, struct arglist *arglist)
+{
+ struct ifsregion *ifsp;
+ struct strlist *sp;
+ char *start;
+ char *p;
+ char *q;
+ const char *ifs;
+ const char *ifsspc;
+ int inquotes;
+
+ start = string;
+ ifsspc = NULL;
+ inquotes = 0;
+
+ if (ifslastp == NULL) {
+ /* Return entire argument, IFS doesn't apply to any of it */
+ sp = (struct strlist *)stalloc(sizeof *sp);
+ sp->text = start;
+ *arglist->lastp = sp;
+ arglist->lastp = &sp->next;
+ return;
+ }
+
+ ifs = ifsset() ? ifsval() : " \t\n";
+
+ for (ifsp = &ifsfirst; ifsp != NULL; ifsp = ifsp->next) {
+ p = string + ifsp->begoff;
+ inquotes = ifsp->inquotes;
+ ifsspc = NULL;
+ while (p < string + ifsp->endoff) {
+ q = p;
+ if (*p == CTLESC)
+ p++;
+ if (inquotes) {
+ /* Only NULs (probably from "$@") end args */
+ if (*p != 0) {
+ p++;
+ continue;
+ }
+ } else {
+ if (!strchr(ifs, *p)) {
+ p++;
+ continue;
+ }
+ ifsspc = strchr(" \t\n", *p);
+
+ /* Ignore IFS whitespace at start */
+ if (q == start && ifsspc != NULL) {
+ p++;
+ start = p;
+ continue;
+ }
+ }
+
+ /* Save this argument... */
+ *q = '\0';
+ sp = (struct strlist *)stalloc(sizeof *sp);
+ sp->text = start;
+ *arglist->lastp = sp;
+ arglist->lastp = &sp->next;
+ p++;
+
+ if (ifsspc != NULL) {
+ /* Ignore further trailing IFS whitespace */
+ for (; p < string + ifsp->endoff; p++) {
+ q = p;
+ if (*p == CTLESC)
+ p++;
+ if (strchr(ifs, *p) == NULL) {
+ p = q;
+ break;
+ }
+ if (strchr(" \t\n", *p) == NULL) {
+ p++;
+ break;
+ }
+ }
+ }
+ start = p;
+ }
+ }
+
+ /*
+ * Save anything left as an argument.
+ * Traditionally we have treated 'IFS=':'; set -- x$IFS' as
+ * generating 2 arguments, the second of which is empty.
+ * Some recent clarification of the Posix spec say that it
+ * should only generate one....
+ */
+ if (*start /* || (!ifsspc && start > string) */) {
+ sp = (struct strlist *)stalloc(sizeof *sp);
+ sp->text = start;
+ *arglist->lastp = sp;
+ arglist->lastp = &sp->next;
+ }
+}
+
+STATIC void
+ifsfree(void)
+{
+ while (ifsfirst.next != NULL) {
+ struct ifsregion *ifsp;
+ INTOFF;
+ ifsp = ifsfirst.next->next;
+ ckfree(ifsfirst.next);
+ ifsfirst.next = ifsp;
+ INTON;
+ }
+ ifslastp = NULL;
+ ifsfirst.next = NULL;
+}
+
+
+
+/*
+ * Expand shell metacharacters. At this point, the only control characters
+ * should be escapes. The results are stored in the list exparg.
+ */
+
+char *expdir;
+
+
+STATIC void
+expandmeta(struct strlist *str, int flag)
+{
+ char *p;
+ struct strlist **savelastp;
+ struct strlist *sp;
+ char c;
+ /* TODO - EXP_REDIR */
+
+ while (str) {
+ if (fflag)
+ goto nometa;
+ p = str->text;
+ for (;;) { /* fast check for meta chars */
+ if ((c = *p++) == '\0')
+ goto nometa;
+ if (c == '*' || c == '?' || c == '[' || c == '!')
+ break;
+ }
+ savelastp = exparg.lastp;
+ INTOFF;
+ if (expdir == NULL) {
+ int i = strlen(str->text);
+ expdir = ckmalloc(i < 2048 ? 2048 : i); /* XXX */
+ }
+
+ expmeta(expdir, str->text);
+ ckfree(expdir);
+ expdir = NULL;
+ INTON;
+ if (exparg.lastp == savelastp) {
+ /*
+ * no matches
+ */
+nometa:
+ *exparg.lastp = str;
+ rmescapes(str->text);
+ exparg.lastp = &str->next;
+ } else {
+ *exparg.lastp = NULL;
+ *savelastp = sp = expsort(*savelastp);
+ while (sp->next != NULL)
+ sp = sp->next;
+ exparg.lastp = &sp->next;
+ }
+ str = str->next;
+ }
+}
+
+
+/*
+ * Do metacharacter (i.e. *, ?, [...]) expansion.
+ */
+
+STATIC void
+expmeta(char *enddir, char *name)
+{
+ char *p;
+ const char *cp;
+ char *q;
+ char *start;
+ char *endname;
+ int metaflag;
+ struct stat statb;
+ DIR *dirp;
+ struct dirent *dp;
+ int atend;
+ int matchdot;
+
+ metaflag = 0;
+ start = name;
+ for (p = name ; ; p++) {
+ if (*p == '*' || *p == '?')
+ metaflag = 1;
+ else if (*p == '[') {
+ q = p + 1;
+ if (*q == '!')
+ q++;
+ for (;;) {
+ while (*q == CTLQUOTEMARK)
+ q++;
+ if (*q == CTLESC)
+ q++;
+ if (*q == '/' || *q == '\0')
+ break;
+ if (*++q == ']') {
+ metaflag = 1;
+ break;
+ }
+ }
+ } else if (*p == '!' && p[1] == '!' && (p == name || p[-1] == '/')) {
+ metaflag = 1;
+ } else if (*p == '\0')
+ break;
+ else if (*p == CTLQUOTEMARK)
+ continue;
+ else if (*p == CTLESC)
+ p++;
+ if (*p == '/') {
+ if (metaflag)
+ break;
+ start = p + 1;
+ }
+ }
+ if (metaflag == 0) { /* we've reached the end of the file name */
+ if (enddir != expdir)
+ metaflag++;
+ for (p = name ; ; p++) {
+ if (*p == CTLQUOTEMARK)
+ continue;
+ if (*p == CTLESC)
+ p++;
+ *enddir++ = *p;
+ if (*p == '\0')
+ break;
+ }
+ if (metaflag == 0 || lstat(expdir, &statb) >= 0)
+ addfname(expdir);
+ return;
+ }
+ endname = p;
+ if (start != name) {
+ p = name;
+ while (p < start) {
+ while (*p == CTLQUOTEMARK)
+ p++;
+ if (*p == CTLESC)
+ p++;
+ *enddir++ = *p++;
+ }
+ }
+ if (enddir == expdir) {
+ cp = ".";
+ } else if (enddir == expdir + 1 && *expdir == '/') {
+ cp = "/";
+ } else {
+ cp = expdir;
+ enddir[-1] = '\0';
+ }
+ if ((dirp = opendir(cp)) == NULL)
+ return;
+ if (enddir != expdir)
+ enddir[-1] = '/';
+ if (*endname == 0) {
+ atend = 1;
+ } else {
+ atend = 0;
+ *endname++ = '\0';
+ }
+ matchdot = 0;
+ p = start;
+ while (*p == CTLQUOTEMARK)
+ p++;
+ if (*p == CTLESC)
+ p++;
+ if (*p == '.')
+ matchdot++;
+ while (! int_pending() && (dp = readdir(dirp)) != NULL) {
+ if (dp->d_name[0] == '.' && ! matchdot)
+ continue;
+ if (patmatch(start, dp->d_name, 0)) {
+ if (atend) {
+ scopy(dp->d_name, enddir);
+ addfname(expdir);
+ } else {
+ for (p = enddir, cp = dp->d_name;
+ (*p++ = *cp++) != '\0';)
+ continue;
+ p[-1] = '/';
+ expmeta(p, endname);
+ }
+ }
+ }
+ closedir(dirp);
+ if (! atend)
+ endname[-1] = '/';
+}
+
+
+/*
+ * Add a file name to the list.
+ */
+
+STATIC void
+addfname(char *name)
+{
+ char *p;
+ struct strlist *sp;
+
+ p = stalloc(strlen(name) + 1);
+ scopy(name, p);
+ sp = (struct strlist *)stalloc(sizeof *sp);
+ sp->text = p;
+ *exparg.lastp = sp;
+ exparg.lastp = &sp->next;
+}
+
+
+/*
+ * Sort the results of file name expansion. It calculates the number of
+ * strings to sort and then calls msort (short for merge sort) to do the
+ * work.
+ */
+
+STATIC struct strlist *
+expsort(struct strlist *str)
+{
+ int len;
+ struct strlist *sp;
+
+ len = 0;
+ for (sp = str ; sp ; sp = sp->next)
+ len++;
+ return msort(str, len);
+}
+
+
+STATIC struct strlist *
+msort(struct strlist *list, int len)
+{
+ struct strlist *p, *q = NULL;
+ struct strlist **lpp;
+ int half;
+ int n;
+
+ if (len <= 1)
+ return list;
+ half = len >> 1;
+ p = list;
+ for (n = half ; --n >= 0 ; ) {
+ q = p;
+ p = p->next;
+ }
+ q->next = NULL; /* terminate first half of list */
+ q = msort(list, half); /* sort first half of list */
+ p = msort(p, len - half); /* sort second half */
+ lpp = &list;
+ for (;;) {
+ if (strcmp(p->text, q->text) < 0) {
+ *lpp = p;
+ lpp = &p->next;
+ if ((p = *lpp) == NULL) {
+ *lpp = q;
+ break;
+ }
+ } else {
+ *lpp = q;
+ lpp = &q->next;
+ if ((q = *lpp) == NULL) {
+ *lpp = p;
+ break;
+ }
+ }
+ }
+ return list;
+}
+
+
+
+/*
+ * Returns true if the pattern matches the string.
+ */
+
+int
+patmatch(char *pattern, char *string, int squoted)
+{
+#ifdef notdef
+ if (pattern[0] == '!' && pattern[1] == '!')
+ return 1 - pmatch(pattern + 2, string);
+ else
+#endif
+ return pmatch(pattern, string, squoted);
+}
+
+
+STATIC int
+pmatch(char *pattern, char *string, int squoted)
+{
+ char *p, *q;
+ char c;
+
+ p = pattern;
+ q = string;
+ for (;;) {
+ switch (c = *p++) {
+ case '\0':
+ goto breakloop;
+ case CTLESC:
+ if (squoted && *q == CTLESC)
+ q++;
+ if (*q++ != *p++)
+ return 0;
+ break;
+ case CTLQUOTEMARK:
+ continue;
+ case '?':
+ if (squoted && *q == CTLESC)
+ q++;
+ if (*q++ == '\0')
+ return 0;
+ break;
+ case '*':
+ c = *p;
+ while (c == CTLQUOTEMARK || c == '*')
+ c = *++p;
+ if (c != CTLESC && c != CTLQUOTEMARK &&
+ c != '?' && c != '*' && c != '[') {
+ while (*q != c) {
+ if (squoted && *q == CTLESC &&
+ q[1] == c)
+ break;
+ if (*q == '\0')
+ return 0;
+ if (squoted && *q == CTLESC)
+ q++;
+ q++;
+ }
+ }
+ do {
+ if (pmatch(p, q, squoted))
+ return 1;
+ if (squoted && *q == CTLESC)
+ q++;
+ } while (*q++ != '\0');
+ return 0;
+ case '[': {
+ char *endp;
+ int invert, found;
+ char chr;
+
+ endp = p;
+ if (*endp == '!')
+ endp++;
+ for (;;) {
+ while (*endp == CTLQUOTEMARK)
+ endp++;
+ if (*endp == '\0')
+ goto dft; /* no matching ] */
+ if (*endp == CTLESC)
+ endp++;
+ if (*++endp == ']')
+ break;
+ }
+ invert = 0;
+ if (*p == '!') {
+ invert++;
+ p++;
+ }
+ found = 0;
+ chr = *q++;
+ if (squoted && chr == CTLESC)
+ chr = *q++;
+ if (chr == '\0')
+ return 0;
+ c = *p++;
+ do {
+ if (c == CTLQUOTEMARK)
+ continue;
+ if (c == CTLESC)
+ c = *p++;
+ if (*p == '-' && p[1] != ']') {
+ p++;
+ while (*p == CTLQUOTEMARK)
+ p++;
+ if (*p == CTLESC)
+ p++;
+ if (chr >= c && chr <= *p)
+ found = 1;
+ p++;
+ } else {
+ if (chr == c)
+ found = 1;
+ }
+ } while ((c = *p++) != ']');
+ if (found == invert)
+ return 0;
+ break;
+ }
+dft: default:
+ if (squoted && *q == CTLESC)
+ q++;
+ if (*q++ != c)
+ return 0;
+ break;
+ }
+ }
+breakloop:
+ if (*q != '\0')
+ return 0;
+ return 1;
+}
+
+
+
+/*
+ * Remove any CTLESC characters from a string.
+ */
+
+void
+rmescapes(char *str)
+{
+ char *p, *q;
+
+ p = str;
+ while (*p != CTLESC && *p != CTLQUOTEMARK) {
+ if (*p++ == '\0')
+ return;
+ }
+ q = p;
+ while (*p) {
+ if (*p == CTLQUOTEMARK) {
+ p++;
+ continue;
+ }
+ if (*p == CTLESC)
+ p++;
+ *q++ = *p++;
+ }
+ *q = '\0';
+}
+
+
+
+/*
+ * See if a pattern matches in a case statement.
+ */
+
+int
+casematch(union node *pattern, char *val)
+{
+ struct stackmark smark;
+ int result;
+ char *p;
+
+ setstackmark(&smark);
+ argbackq = pattern->narg.backquote;
+ STARTSTACKSTR(expdest);
+ ifslastp = NULL;
+ argstr(pattern->narg.text, EXP_TILDE | EXP_CASE);
+ STPUTC('\0', expdest);
+ p = grabstackstr(expdest);
+ result = patmatch(p, val, 0);
+ popstackmark(&smark);
+ return result;
+}
+
+/*
+ * Our own itoa().
+ */
+
+STATIC char *
+cvtnum(int num, char *buf)
+{
+ char temp[32];
+ int neg = num < 0;
+ char *p = temp + 31;
+
+ temp[31] = '\0';
+
+ do {
+ *--p = num % 10 + '0';
+ } while ((num /= 10) != 0);
+
+ if (neg)
+ *--p = '-';
+
+ while (*p)
+ STPUTC(*p++, buf);
+ return buf;
+}
+
+/*
+ * Do most of the work for wordexp(3).
+ */
+
+int
+wordexpcmd(int argc, char **argv)
+{
+ size_t len;
+ int i;
+
+ out1fmt("%d", argc - 1);
+ out1c('\0');
+ for (i = 1, len = 0; i < argc; i++)
+ len += strlen(argv[i]);
+ out1fmt("%zd", len);
+ out1c('\0');
+ for (i = 1; i < argc; i++) {
+ out1str(argv[i]);
+ out1c('\0');
+ }
+ return (0);
+}