/* $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;
}
}