freebsd-nq/bin/sh/alias.c
Peter Wemm aa9caaf657 Merge of 4.4-Lite2 sh source, plus some gcc -Wall cleaning. This is a
merge of parallel duplicate work by Steve Price and myself. :-]

There are some changes to the build that are my fault...  mkinit.c was
trying (poorly) to duplicate some of the work that make(1) is designed to
do.  The Makefile hackery is my fault too, the depend list was incomplete
because of some explicit OBJS+= entries, so mkdep wasn't picking up their
source file #includes.

This closes a pile of /bin/sh PR's, but not all of them..

Submitted by: Steve Price <steve@bonsai.hiwaay.net>, peter
1996-09-01 10:22:36 +00:00

263 lines
6.2 KiB
C

/*-
* Copyright (c) 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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.
*
* $Id: alias.c,v 1.3 1995/05/30 00:07:10 rgrimes Exp $
*/
#ifndef lint
static char sccsid[] = "@(#)alias.c 8.3 (Berkeley) 5/4/95";
#endif /* not lint */
#include <stdlib.h>
#include "shell.h"
#include "input.h"
#include "output.h"
#include "error.h"
#include "memalloc.h"
#include "mystring.h"
#include "alias.h"
#include "options.h" /* XXX for argptr (should remove?) */
#define ATABSIZE 39
struct alias *atab[ATABSIZE];
STATIC void setalias __P((char *, char *));
STATIC int unalias __P((char *));
STATIC struct alias **hashalias __P((char *));
STATIC
void
setalias(name, val)
char *name, *val;
{
struct alias *ap, **app;
app = hashalias(name);
for (ap = *app; ap; ap = ap->next) {
if (equal(name, ap->name)) {
INTOFF;
ckfree(ap->val);
ap->val = savestr(val);
INTON;
return;
}
}
/* not found */
INTOFF;
ap = ckmalloc(sizeof (struct alias));
ap->name = savestr(name);
/*
* XXX - HACK: in order that the parser will not finish reading the
* alias value off the input before processing the next alias, we
* dummy up an extra space at the end of the alias. This is a crock
* and should be re-thought. The idea (if you feel inclined to help)
* is to avoid alias recursions. The mechanism used is: when
* expanding an alias, the value of the alias is pushed back on the
* input as a string and a pointer to the alias is stored with the
* string. The alias is marked as being in use. When the input
* routine finishes reading the string, it markes the alias not
* in use. The problem is synchronization with the parser. Since
* it reads ahead, the alias is marked not in use before the
* resulting token(s) is next checked for further alias sub. The
* H A C K is that we add a little fluff after the alias value
* so that the string will not be exhausted. This is a good
* idea ------- ***NOT***
*/
#ifdef notyet
ap->val = savestr(val);
#else /* hack */
{
int len = strlen(val);
ap->val = ckmalloc(len + 2);
memcpy(ap->val, val, len);
ap->val[len] = ' '; /* fluff */
ap->val[len+1] = '\0';
}
#endif
ap->next = *app;
*app = ap;
INTON;
}
STATIC int
unalias(name)
char *name;
{
struct alias *ap, **app;
app = hashalias(name);
for (ap = *app; ap; app = &(ap->next), ap = ap->next) {
if (equal(name, ap->name)) {
/*
* if the alias is currently in use (i.e. its
* buffer is being used by the input routine) we
* just null out the name instead of freeing it.
* We could clear it out later, but this situation
* is so rare that it hardly seems worth it.
*/
if (ap->flag & ALIASINUSE)
*ap->name = '\0';
else {
INTOFF;
*app = ap->next;
ckfree(ap->name);
ckfree(ap->val);
ckfree(ap);
INTON;
}
return (0);
}
}
return (1);
}
#ifdef mkinit
MKINIT void rmaliases();
SHELLPROC {
rmaliases();
}
#endif
void
rmaliases() {
struct alias *ap, *tmp;
int i;
INTOFF;
for (i = 0; i < ATABSIZE; i++) {
ap = atab[i];
atab[i] = NULL;
while (ap) {
ckfree(ap->name);
ckfree(ap->val);
tmp = ap;
ap = ap->next;
ckfree(tmp);
}
}
INTON;
}
struct alias *
lookupalias(name, check)
char *name;
int check;
{
struct alias *ap = *hashalias(name);
for (; ap; ap = ap->next) {
if (equal(name, ap->name)) {
if (check && (ap->flag & ALIASINUSE))
return (NULL);
return (ap);
}
}
return (NULL);
}
/*
* TODO - sort output
*/
int
aliascmd(argc, argv)
int argc;
char **argv;
{
char *n, *v;
int ret = 0;
struct alias *ap;
if (argc == 1) {
int i;
for (i = 0; i < ATABSIZE; i++)
for (ap = atab[i]; ap; ap = ap->next) {
if (*ap->name != '\0')
out1fmt("alias %s=%s\n", ap->name, ap->val);
}
return (0);
}
while ((n = *++argv) != NULL) {
if ((v = strchr(n+1, '=')) == NULL) /* n+1: funny ksh stuff */
if ((ap = lookupalias(n, 0)) == NULL) {
outfmt(out2, "alias: %s not found\n", n);
ret = 1;
} else
out1fmt("alias %s=%s\n", n, ap->val);
else {
*v++ = '\0';
setalias(n, v);
}
}
return (ret);
}
int
unaliascmd(argc, argv)
int argc;
char **argv;
{
int i;
while ((i = nextopt("a")) != '\0') {
if (i == 'a') {
rmaliases();
return (0);
}
}
for (i = 0; *argptr; argptr++)
i = unalias(*argptr);
return (i);
}
STATIC struct alias **
hashalias(p)
register char *p;
{
unsigned int hashval;
hashval = *p << 4;
while (*p)
hashval+= *p++;
return &atab[hashval % ATABSIZE];
}