auto import from //depot/cupcake/@135843
diff --git a/sh/input.c b/sh/input.c
new file mode 100644
index 0000000..a81fd7b
--- /dev/null
+++ b/sh/input.c
@@ -0,0 +1,531 @@
+/* $NetBSD: input.c,v 1.39 2003/08/07 09:05:32 agc 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[] = "@(#)input.c 8.3 (Berkeley) 6/9/95";
+#else
+__RCSID("$NetBSD: input.c,v 1.39 2003/08/07 09:05:32 agc Exp $");
+#endif
+#endif /* not lint */
+
+#include <stdio.h> /* defines BUFSIZ */
+#include <fcntl.h>
+#include <errno.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+
+/*
+ * This file implements the input routines used by the parser.
+ */
+
+#include "shell.h"
+#include "redir.h"
+#include "syntax.h"
+#include "input.h"
+#include "output.h"
+#include "options.h"
+#include "memalloc.h"
+#include "error.h"
+#include "alias.h"
+#include "parser.h"
+#include "myhistedit.h"
+
+#define EOF_NLEFT -99 /* value of parsenleft when EOF pushed back */
+
+MKINIT
+struct strpush {
+ struct strpush *prev; /* preceding string on stack */
+ char *prevstring;
+ int prevnleft;
+ int prevlleft;
+ struct alias *ap; /* if push was associated with an alias */
+};
+
+/*
+ * The parsefile structure pointed to by the global variable parsefile
+ * contains information about the current file being read.
+ */
+
+MKINIT
+struct parsefile {
+ struct parsefile *prev; /* preceding file on stack */
+ int linno; /* current line */
+ int fd; /* file descriptor (or -1 if string) */
+ int nleft; /* number of chars left in this line */
+ int lleft; /* number of chars left in this buffer */
+ char *nextc; /* next char in buffer */
+ char *buf; /* input buffer */
+ struct strpush *strpush; /* for pushing strings at this level */
+ struct strpush basestrpush; /* so pushing one is fast */
+};
+
+
+int plinno = 1; /* input line number */
+int parsenleft; /* copy of parsefile->nleft */
+MKINIT int parselleft; /* copy of parsefile->lleft */
+char *parsenextc; /* copy of parsefile->nextc */
+MKINIT struct parsefile basepf; /* top level input file */
+MKINIT char basebuf[BUFSIZ]; /* buffer for top level input file */
+struct parsefile *parsefile = &basepf; /* current input file */
+int init_editline = 0; /* editline library initialized? */
+int whichprompt; /* 1 == PS1, 2 == PS2 */
+
+#if WITH_HISTORY
+EditLine *el; /* cookie for editline package */
+#endif
+
+STATIC void pushfile(void);
+static int preadfd(void);
+
+#ifdef mkinit
+INCLUDE <stdio.h>
+INCLUDE "input.h"
+INCLUDE "error.h"
+
+INIT {
+ basepf.nextc = basepf.buf = basebuf;
+}
+
+RESET {
+ if (exception != EXSHELLPROC)
+ parselleft = parsenleft = 0; /* clear input buffer */
+ popallfiles();
+}
+
+SHELLPROC {
+ popallfiles();
+}
+#endif
+
+
+/*
+ * Read a line from the script.
+ */
+
+char *
+pfgets(char *line, int len)
+{
+ char *p = line;
+ int nleft = len;
+ int c;
+
+ while (--nleft > 0) {
+ c = pgetc_macro();
+ if (c == PEOF) {
+ if (p == line)
+ return NULL;
+ break;
+ }
+ *p++ = c;
+ if (c == '\n')
+ break;
+ }
+ *p = '\0';
+ return line;
+}
+
+
+
+/*
+ * Read a character from the script, returning PEOF on end of file.
+ * Nul characters in the input are silently discarded.
+ */
+
+int
+pgetc(void)
+{
+ return pgetc_macro();
+}
+
+
+static int
+preadfd(void)
+{
+ int nr;
+ char *buf = parsefile->buf;
+ parsenextc = buf;
+
+retry:
+#ifdef WITH_HISTORY
+ if (parsefile->fd == 0 && el) {
+ static const char *rl_cp;
+ static int el_len;
+
+ if (rl_cp == NULL)
+ rl_cp = el_gets(el, &el_len);
+ if (rl_cp == NULL)
+ nr = 0;
+ else {
+ nr = el_len;
+ if (nr > BUFSIZ - 8)
+ nr = BUFSIZ - 8;
+ memcpy(buf, rl_cp, nr);
+ if (nr != el_len) {
+ el_len -= nr;
+ rl_cp += nr;
+ } else
+ rl_cp = 0;
+ }
+
+ } else
+#endif
+ nr = read(parsefile->fd, buf, BUFSIZ - 8);
+
+
+ if (nr <= 0) {
+ if (nr < 0) {
+ if (errno == EINTR)
+ goto retry;
+ if (parsefile->fd == 0 && errno == EWOULDBLOCK) {
+ int flags = fcntl(0, F_GETFL, 0);
+ if (flags >= 0 && flags & O_NONBLOCK) {
+ flags &=~ O_NONBLOCK;
+ if (fcntl(0, F_SETFL, flags) >= 0) {
+ out2str("sh: turning off NDELAY mode\n");
+ goto retry;
+ }
+ }
+ }
+ }
+ nr = -1;
+ }
+ return nr;
+}
+
+/*
+ * Refill the input buffer and return the next input character:
+ *
+ * 1) If a string was pushed back on the input, pop it;
+ * 2) If an EOF was pushed back (parsenleft == EOF_NLEFT) or we are reading
+ * from a string so we can't refill the buffer, return EOF.
+ * 3) If the is more stuff in this buffer, use it else call read to fill it.
+ * 4) Process input up to the next newline, deleting nul characters.
+ */
+
+int
+preadbuffer(void)
+{
+ char *p, *q;
+ int more;
+ int something;
+ char savec;
+
+ if (parsefile->strpush) {
+ popstring();
+ if (--parsenleft >= 0)
+ return (*parsenextc++);
+ }
+ if (parsenleft == EOF_NLEFT || parsefile->buf == NULL)
+ return PEOF;
+ flushout(&output);
+ flushout(&errout);
+
+again:
+ if (parselleft <= 0) {
+ if ((parselleft = preadfd()) == -1) {
+ parselleft = parsenleft = EOF_NLEFT;
+ return PEOF;
+ }
+ }
+
+ q = p = parsenextc;
+
+ /* delete nul characters */
+ something = 0;
+ for (more = 1; more;) {
+ switch (*p) {
+ case '\0':
+ p++; /* Skip nul */
+ goto check;
+
+ case '\t':
+ case ' ':
+ break;
+
+ case '\n':
+ parsenleft = q - parsenextc;
+ more = 0; /* Stop processing here */
+ break;
+
+ default:
+ something = 1;
+ break;
+ }
+
+ *q++ = *p++;
+check:
+ if (--parselleft <= 0) {
+ parsenleft = q - parsenextc - 1;
+ if (parsenleft < 0)
+ goto again;
+ *q = '\0';
+ more = 0;
+ }
+ }
+
+ savec = *q;
+ *q = '\0';
+
+#ifdef WITH_HISTORY
+ if (parsefile->fd == 0 && hist && something) {
+ HistEvent he;
+ INTOFF;
+ history(hist, &he, whichprompt == 1? H_ENTER : H_APPEND,
+ parsenextc);
+ INTON;
+ }
+#endif
+
+ if (vflag) {
+ out2str(parsenextc);
+ flushout(out2);
+ }
+
+ *q = savec;
+
+ return *parsenextc++;
+}
+
+/*
+ * Undo the last call to pgetc. Only one character may be pushed back.
+ * PEOF may be pushed back.
+ */
+
+void
+pungetc(void)
+{
+ parsenleft++;
+ parsenextc--;
+}
+
+/*
+ * Push a string back onto the input at this current parsefile level.
+ * We handle aliases this way.
+ */
+void
+pushstring(char *s, int len, void *ap)
+{
+ struct strpush *sp;
+
+ INTOFF;
+/*dprintf("*** calling pushstring: %s, %d\n", s, len);*/
+ if (parsefile->strpush) {
+ sp = ckmalloc(sizeof (struct strpush));
+ sp->prev = parsefile->strpush;
+ parsefile->strpush = sp;
+ } else
+ sp = parsefile->strpush = &(parsefile->basestrpush);
+ sp->prevstring = parsenextc;
+ sp->prevnleft = parsenleft;
+ sp->prevlleft = parselleft;
+ sp->ap = (struct alias *)ap;
+ if (ap)
+ ((struct alias *)ap)->flag |= ALIASINUSE;
+ parsenextc = s;
+ parsenleft = len;
+ INTON;
+}
+
+void
+popstring(void)
+{
+ struct strpush *sp = parsefile->strpush;
+
+ INTOFF;
+ parsenextc = sp->prevstring;
+ parsenleft = sp->prevnleft;
+ parselleft = sp->prevlleft;
+/*dprintf("*** calling popstring: restoring to '%s'\n", parsenextc);*/
+ if (sp->ap)
+ sp->ap->flag &= ~ALIASINUSE;
+ parsefile->strpush = sp->prev;
+ if (sp != &(parsefile->basestrpush))
+ ckfree(sp);
+ INTON;
+}
+
+/*
+ * Set the input to take input from a file. If push is set, push the
+ * old input onto the stack first.
+ */
+
+void
+setinputfile(const char *fname, int push)
+{
+ int fd;
+ int fd2;
+
+ INTOFF;
+ if ((fd = open(fname, O_RDONLY)) < 0)
+ error("Can't open %s", fname);
+ if (fd < 10) {
+ fd2 = copyfd(fd, 10);
+ close(fd);
+ if (fd2 < 0)
+ error("Out of file descriptors");
+ fd = fd2;
+ }
+ setinputfd(fd, push);
+ INTON;
+}
+
+
+/*
+ * Like setinputfile, but takes an open file descriptor. Call this with
+ * interrupts off.
+ */
+
+void
+setinputfd(int fd, int push)
+{
+ (void) fcntl(fd, F_SETFD, FD_CLOEXEC);
+ if (push) {
+ pushfile();
+ parsefile->buf = ckmalloc(BUFSIZ);
+ }
+ if (parsefile->fd > 0)
+ close(parsefile->fd);
+ parsefile->fd = fd;
+ if (parsefile->buf == NULL)
+ parsefile->buf = ckmalloc(BUFSIZ);
+ parselleft = parsenleft = 0;
+ plinno = 1;
+}
+
+
+/*
+ * Like setinputfile, but takes input from a string.
+ */
+
+void
+setinputstring(char *string, int push)
+{
+ INTOFF;
+ if (push)
+ pushfile();
+ parsenextc = string;
+ parselleft = parsenleft = strlen(string);
+ parsefile->buf = NULL;
+ plinno = 1;
+ INTON;
+}
+
+
+
+/*
+ * To handle the "." command, a stack of input files is used. Pushfile
+ * adds a new entry to the stack and popfile restores the previous level.
+ */
+
+STATIC void
+pushfile(void)
+{
+ struct parsefile *pf;
+
+ parsefile->nleft = parsenleft;
+ parsefile->lleft = parselleft;
+ parsefile->nextc = parsenextc;
+ parsefile->linno = plinno;
+ pf = (struct parsefile *)ckmalloc(sizeof (struct parsefile));
+ pf->prev = parsefile;
+ pf->fd = -1;
+ pf->strpush = NULL;
+ pf->basestrpush.prev = NULL;
+ parsefile = pf;
+}
+
+
+void
+popfile(void)
+{
+ struct parsefile *pf = parsefile;
+
+ INTOFF;
+ if (pf->fd >= 0)
+ close(pf->fd);
+ if (pf->buf)
+ ckfree(pf->buf);
+ while (pf->strpush)
+ popstring();
+ parsefile = pf->prev;
+ ckfree(pf);
+ parsenleft = parsefile->nleft;
+ parselleft = parsefile->lleft;
+ parsenextc = parsefile->nextc;
+ plinno = parsefile->linno;
+ INTON;
+}
+
+
+/*
+ * Return to top level.
+ */
+
+void
+popallfiles(void)
+{
+ while (parsefile != &basepf)
+ popfile();
+}
+
+
+
+/*
+ * Close the file(s) that the shell is reading commands from. Called
+ * after a fork is done.
+ *
+ * Takes one arg, vfork, which tells it to not modify its global vars
+ * as it is still running in the parent.
+ *
+ * This code is (probably) unnecessary as the 'close on exec' flag is
+ * set and should be enough. In the vfork case it is definitely wrong
+ * to close the fds as another fork() may be done later to feed data
+ * from a 'here' document into a pipe and we don't want to close the
+ * pipe!
+ */
+
+void
+closescript(int vforked)
+{
+ if (vforked)
+ return;
+ popallfiles();
+ if (parsefile->fd > 0) {
+ close(parsefile->fd);
+ parsefile->fd = 0;
+ }
+}