auto import from //depot/cupcake/@135843
diff --git a/sh/show.c b/sh/show.c
new file mode 100644
index 0000000..e92aa51
--- /dev/null
+++ b/sh/show.c
@@ -0,0 +1,425 @@
+/* $NetBSD: show.c,v 1.26 2003/11/14 10:46:13 dsl 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[] = "@(#)show.c 8.3 (Berkeley) 5/4/95";
+#else
+__RCSID("$NetBSD: show.c,v 1.26 2003/11/14 10:46:13 dsl Exp $");
+#endif
+#endif /* not lint */
+
+#include <stdio.h>
+#include <stdarg.h>
+#include <stdlib.h>
+
+#include "shell.h"
+#include "parser.h"
+#include "nodes.h"
+#include "mystring.h"
+#include "show.h"
+#include "options.h"
+
+
+#ifdef DEBUG
+static void shtree(union node *, int, char *, FILE*);
+static void shcmd(union node *, FILE *);
+static void sharg(union node *, FILE *);
+static void indent(int, char *, FILE *);
+static void trstring(char *);
+
+
+void
+showtree(union node *n)
+{
+ trputs("showtree called\n");
+ shtree(n, 1, NULL, stdout);
+}
+
+
+static void
+shtree(union node *n, int ind, char *pfx, FILE *fp)
+{
+ struct nodelist *lp;
+ const char *s;
+
+ if (n == NULL)
+ return;
+
+ indent(ind, pfx, fp);
+ switch(n->type) {
+ case NSEMI:
+ s = "; ";
+ goto binop;
+ case NAND:
+ s = " && ";
+ goto binop;
+ case NOR:
+ s = " || ";
+binop:
+ shtree(n->nbinary.ch1, ind, NULL, fp);
+ /* if (ind < 0) */
+ fputs(s, fp);
+ shtree(n->nbinary.ch2, ind, NULL, fp);
+ break;
+ case NCMD:
+ shcmd(n, fp);
+ if (ind >= 0)
+ putc('\n', fp);
+ break;
+ case NPIPE:
+ for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) {
+ shcmd(lp->n, fp);
+ if (lp->next)
+ fputs(" | ", fp);
+ }
+ if (n->npipe.backgnd)
+ fputs(" &", fp);
+ if (ind >= 0)
+ putc('\n', fp);
+ break;
+ default:
+ fprintf(fp, "<node type %d>", n->type);
+ if (ind >= 0)
+ putc('\n', fp);
+ break;
+ }
+}
+
+
+
+static void
+shcmd(union node *cmd, FILE *fp)
+{
+ union node *np;
+ int first;
+ const char *s;
+ int dftfd;
+
+ first = 1;
+ for (np = cmd->ncmd.args ; np ; np = np->narg.next) {
+ if (! first)
+ putchar(' ');
+ sharg(np, fp);
+ first = 0;
+ }
+ for (np = cmd->ncmd.redirect ; np ; np = np->nfile.next) {
+ if (! first)
+ putchar(' ');
+ switch (np->nfile.type) {
+ case NTO: s = ">"; dftfd = 1; break;
+ case NCLOBBER: s = ">|"; dftfd = 1; break;
+ case NAPPEND: s = ">>"; dftfd = 1; break;
+ case NTOFD: s = ">&"; dftfd = 1; break;
+ case NFROM: s = "<"; dftfd = 0; break;
+ case NFROMFD: s = "<&"; dftfd = 0; break;
+ case NFROMTO: s = "<>"; dftfd = 0; break;
+ default: s = "*error*"; dftfd = 0; break;
+ }
+ if (np->nfile.fd != dftfd)
+ fprintf(fp, "%d", np->nfile.fd);
+ fputs(s, fp);
+ if (np->nfile.type == NTOFD || np->nfile.type == NFROMFD) {
+ fprintf(fp, "%d", np->ndup.dupfd);
+ } else {
+ sharg(np->nfile.fname, fp);
+ }
+ first = 0;
+ }
+}
+
+
+
+static void
+sharg(union node *arg, FILE *fp)
+{
+ char *p;
+ struct nodelist *bqlist;
+ int subtype;
+
+ if (arg->type != NARG) {
+ printf("<node type %d>\n", arg->type);
+ abort();
+ }
+ bqlist = arg->narg.backquote;
+ for (p = arg->narg.text ; *p ; p++) {
+ switch (*p) {
+ case CTLESC:
+ putc(*++p, fp);
+ break;
+ case CTLVAR:
+ putc('$', fp);
+ putc('{', fp);
+ subtype = *++p;
+ if (subtype == VSLENGTH)
+ putc('#', fp);
+
+ while (*p != '=')
+ putc(*p++, fp);
+
+ if (subtype & VSNUL)
+ putc(':', fp);
+
+ switch (subtype & VSTYPE) {
+ case VSNORMAL:
+ putc('}', fp);
+ break;
+ case VSMINUS:
+ putc('-', fp);
+ break;
+ case VSPLUS:
+ putc('+', fp);
+ break;
+ case VSQUESTION:
+ putc('?', fp);
+ break;
+ case VSASSIGN:
+ putc('=', fp);
+ break;
+ case VSTRIMLEFT:
+ putc('#', fp);
+ break;
+ case VSTRIMLEFTMAX:
+ putc('#', fp);
+ putc('#', fp);
+ break;
+ case VSTRIMRIGHT:
+ putc('%', fp);
+ break;
+ case VSTRIMRIGHTMAX:
+ putc('%', fp);
+ putc('%', fp);
+ break;
+ case VSLENGTH:
+ break;
+ default:
+ printf("<subtype %d>", subtype);
+ }
+ break;
+ case CTLENDVAR:
+ putc('}', fp);
+ break;
+ case CTLBACKQ:
+ case CTLBACKQ|CTLQUOTE:
+ putc('$', fp);
+ putc('(', fp);
+ shtree(bqlist->n, -1, NULL, fp);
+ putc(')', fp);
+ break;
+ default:
+ putc(*p, fp);
+ break;
+ }
+ }
+}
+
+
+static void
+indent(int amount, char *pfx, FILE *fp)
+{
+ int i;
+
+ for (i = 0 ; i < amount ; i++) {
+ if (pfx && i == amount - 1)
+ fputs(pfx, fp);
+ putc('\t', fp);
+ }
+}
+#endif
+
+
+
+/*
+ * Debugging stuff.
+ */
+
+
+FILE *tracefile;
+
+
+#ifdef DEBUG
+void
+trputc(int c)
+{
+ if (debug != 1)
+ return;
+ putc(c, tracefile);
+}
+#endif
+
+void
+trace(const char *fmt, ...)
+{
+#ifdef DEBUG
+ va_list va;
+
+ if (debug != 1)
+ return;
+ va_start(va, fmt);
+ (void) vfprintf(tracefile, fmt, va);
+ va_end(va);
+#endif
+}
+
+void
+tracev(const char *fmt, va_list va)
+{
+#ifdef DEBUG
+ if (debug != 1)
+ return;
+ (void) vfprintf(tracefile, fmt, va);
+#endif
+}
+
+
+#ifdef DEBUG
+void
+trputs(const char *s)
+{
+ if (debug != 1)
+ return;
+ fputs(s, tracefile);
+}
+
+
+static void
+trstring(char *s)
+{
+ char *p;
+ char c;
+
+ if (debug != 1)
+ return;
+ putc('"', tracefile);
+ for (p = s ; *p ; p++) {
+ switch (*p) {
+ case '\n': c = 'n'; goto backslash;
+ case '\t': c = 't'; goto backslash;
+ case '\r': c = 'r'; goto backslash;
+ case '"': c = '"'; goto backslash;
+ case '\\': c = '\\'; goto backslash;
+ case CTLESC: c = 'e'; goto backslash;
+ case CTLVAR: c = 'v'; goto backslash;
+ case CTLVAR+CTLQUOTE: c = 'V'; goto backslash;
+ case CTLBACKQ: c = 'q'; goto backslash;
+ case CTLBACKQ+CTLQUOTE: c = 'Q'; goto backslash;
+backslash: putc('\\', tracefile);
+ putc(c, tracefile);
+ break;
+ default:
+ if (*p >= ' ' && *p <= '~')
+ putc(*p, tracefile);
+ else {
+ putc('\\', tracefile);
+ putc(*p >> 6 & 03, tracefile);
+ putc(*p >> 3 & 07, tracefile);
+ putc(*p & 07, tracefile);
+ }
+ break;
+ }
+ }
+ putc('"', tracefile);
+}
+#endif
+
+
+void
+trargs(char **ap)
+{
+#ifdef DEBUG
+ if (debug != 1)
+ return;
+ while (*ap) {
+ trstring(*ap++);
+ if (*ap)
+ putc(' ', tracefile);
+ else
+ putc('\n', tracefile);
+ }
+#endif
+}
+
+
+#ifdef DEBUG
+void
+opentrace(void)
+{
+ char s[100];
+#ifdef O_APPEND
+ int flags;
+#endif
+
+ if (debug != 1) {
+ if (tracefile)
+ fflush(tracefile);
+ /* leave open because libedit might be using it */
+ return;
+ }
+#ifdef not_this_way
+ {
+ char *p;
+ if ((p = getenv("HOME")) == NULL) {
+ if (geteuid() == 0)
+ p = "/";
+ else
+ p = "/tmp";
+ }
+ scopy(p, s);
+ strcat(s, "/trace");
+ }
+#else
+ scopy("./trace", s);
+#endif /* not_this_way */
+ if (tracefile) {
+ if (!freopen(s, "a", tracefile)) {
+ fprintf(stderr, "Can't re-open %s\n", s);
+ debug = 0;
+ return;
+ }
+ } else {
+ if ((tracefile = fopen(s, "a")) == NULL) {
+ fprintf(stderr, "Can't open %s\n", s);
+ debug = 0;
+ return;
+ }
+ }
+#ifdef O_APPEND
+ if ((flags = fcntl(fileno(tracefile), F_GETFL, 0)) >= 0)
+ fcntl(fileno(tracefile), F_SETFL, flags | O_APPEND);
+#endif
+ setlinebuf(tracefile);
+ fputs("\nTracing started.\n", tracefile);
+}
+#endif /* DEBUG */