/* $NetBSD: alias.c,v 1.20 2018/12/03 06:40:26 kre Exp $ */
/*-
* 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. 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[] = "@(#)alias.c 8.3 (Berkeley) 5/4/95";
#else
__RCSID("$NetBSD: alias.c,v 1.20 2018/12/03 06:40:26 kre Exp $");
#endif
#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?) */
#include "builtins.h"
#include "var.h"
#define ATABSIZE 39
struct alias *atab[ATABSIZE];
STATIC void setalias(char *, char *);
STATIC int by_name(const void *, const void *);
STATIC void list_aliases(void);
STATIC int unalias(char *);
STATIC struct alias **freealias(struct alias **, int);
STATIC struct alias **hashalias(const char *);
STATIC size_t countaliases(void);
STATIC
void
setalias(char *name, char *val)
{
struct alias *ap, **app;
(void) unalias(name); /* old one (if any) is now gone */
app = hashalias(name);
INTOFF;
ap = ckmalloc(sizeof (struct alias));
ap->name = savestr(name);
ap->flag = 0;
ap->val = savestr(val);
ap->next = *app;
*app = ap;
INTON;
}
STATIC struct alias **
freealias(struct alias **app, int force)
{
struct alias *ap = *app;
if (ap == NULL)
return app;
/*
* 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 discarding it.
* If we encounter it later, when it is idle,
* we will finish freeing it then.
*
* Unless we want to simply free everything (INIT)
*/
if (ap->flag & ALIASINUSE && !force) {
*ap->name = '\0';
return &ap->next;
}
INTOFF;
*app = ap->next;
ckfree(ap->name);
ckfree(ap->val);
ckfree(ap);
INTON;
return app;
}
STATIC int
unalias(char *name)
{
struct alias *ap, **app;
app = hashalias(name);
while ((ap = *app) != NULL) {
if (equal(name, ap->name)) {
(void) freealias(app, 0);
return 0;
}
app = &ap->next;
}
return 1;
}
#ifdef mkinit
MKINIT void rmaliases(int);
SHELLPROC {
rmaliases(1);
}
#endif
void
rmaliases(int force)
{
struct alias **app;
int i;
INTOFF;
for (i = 0; i < ATABSIZE; i++) {
app = &atab[i];
while (*app)
app = freealias(app, force);
}
INTON;
}
struct alias *
lookupalias(const char *name, int check)
{
struct alias *ap = *hashalias(name);
while (ap != NULL) {
if (equal(name, ap->name)) {
if (check && (ap->flag & ALIASINUSE))
return NULL;
return ap;
}
ap = ap->next;
}
return NULL;
}
const char *
alias_text(void *dummy __unused, const char *name)
{
struct alias *ap;
ap = lookupalias(name, 0);
if (ap == NULL)
return NULL;
return ap->val;
}
STATIC int
by_name(const void *a, const void *b)
{
return strcmp(
(*(const struct alias * const *)a)->name,
(*(const struct alias * const *)b)->name);
}
STATIC void
list_aliases(void)
{
size_t i, j, n;
const struct alias **aliases;
const struct alias *ap;
INTOFF;
n = countaliases();
aliases = ckmalloc(n * sizeof aliases[0]);
j = 0;
for (i = 0; i < ATABSIZE; i++)
for (ap = atab[i]; ap != NULL; ap = ap->next)
if (ap->name[0] != '\0')
aliases[j++] = ap;
if (j != n)
error("Alias count botch");
INTON;
qsort(aliases, n, sizeof aliases[0], by_name);
for (i = 0; i < n; i++) {
out1fmt("alias %s=", aliases[i]->name);
print_quoted(aliases[i]->val);
out1c('\n');
}
ckfree(aliases);
}
/*
* Count how many aliases are defined (skipping any
* that have been deleted, but don't know it yet).
* Use this opportunity to clean up any of those
* zombies that are no longer needed.
*/
STATIC size_t
countaliases(void)
{
struct alias *ap, **app;
size_t n;
int i;
n = 0;
for (i = 0; i < ATABSIZE; i++)
for (app = &atab[i]; (ap = *app) != NULL;) {
if (ap->name[0] != '\0')
n++;
else {
app = freealias(app, 0);
continue;
}
app = &ap->next;
}
return n;
}
int
aliascmd(int argc, char **argv)
{
char *n, *v;
int ret = 0;
struct alias *ap;
if (argc == 1) {
list_aliases();
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=", n);
print_quoted(ap->val);
out1c('\n');
}
} else {
*v++ = '\0';
setalias(n, v);
}
}
return ret;
}
int
unaliascmd(int argc, char **argv)
{
int i;
while ((i = nextopt("a")) != '\0') {
if (i == 'a') {
rmaliases(0);
return 0;
}
}
(void)countaliases(); /* delete any dead ones */
for (i = 0; *argptr; argptr++)
i |= unalias(*argptr);
return i;
}
STATIC struct alias **
hashalias(const char *p)
{
unsigned int hashval;
hashval = *(const unsigned char *)p << 4;
while (*p)
hashval += *p++;
return &atab[hashval % ATABSIZE];
}
