freebsd-nq/bin/sh/var.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

749 lines
14 KiB
C

/*-
* 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. 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: var.c,v 1.5 1996/08/12 22:14:50 ache Exp $
*/
#ifndef lint
static char sccsid[] = "@(#)var.c 8.3 (Berkeley) 5/4/95";
#endif /* not lint */
#include <unistd.h>
#include <stdlib.h>
/*
* Shell variables.
*/
#include <locale.h>
#include "shell.h"
#include "output.h"
#include "expand.h"
#include "nodes.h" /* for other headers */
#include "eval.h" /* defines cmdenviron */
#include "exec.h"
#include "syntax.h"
#include "options.h"
#include "mail.h"
#include "parser.h"
#include "var.h"
#include "memalloc.h"
#include "error.h"
#include "mystring.h"
#ifndef NO_HISTORY
#include "myhistedit.h"
#endif
#define VTABSIZE 39
struct varinit {
struct var *var;
int flags;
char *text;
};
#if ATTY
struct var vatty;
#endif
#ifndef NO_HISTORY
struct var vhistsize;
#endif
struct var vifs;
struct var vmail;
struct var vmpath;
struct var vpath;
struct var vps1;
struct var vps2;
struct var vvers;
#if ATTY
struct var vterm;
#endif
const struct varinit varinit[] = {
#if ATTY
{&vatty, VSTRFIXED|VTEXTFIXED|VUNSET, "ATTY="},
#endif
#ifndef NO_HISTORY
{&vhistsize, VSTRFIXED|VTEXTFIXED|VUNSET, "HISTSIZE="},
#endif
{&vifs, VSTRFIXED|VTEXTFIXED, "IFS= \t\n"},
{&vmail, VSTRFIXED|VTEXTFIXED|VUNSET, "MAIL="},
{&vmpath, VSTRFIXED|VTEXTFIXED|VUNSET, "MAILPATH="},
{&vpath, VSTRFIXED|VTEXTFIXED, "PATH=/bin:/usr/bin"},
/*
* vps1 depends on uid
*/
{&vps2, VSTRFIXED|VTEXTFIXED, "PS2=> "},
#if ATTY
{&vterm, VSTRFIXED|VTEXTFIXED|VUNSET, "TERM="},
#endif
{NULL, 0, NULL}
};
struct var *vartab[VTABSIZE];
STATIC int unsetvar __P((char *));
STATIC struct var **hashvar __P((char *));
STATIC int varequal __P((char *, char *));
STATIC int localevar __P((char *));
/*
* Initialize the varable symbol tables and import the environment
*/
#ifdef mkinit
INCLUDE "var.h"
INIT {
char **envp;
extern char **environ;
initvar();
for (envp = environ ; *envp ; envp++) {
if (strchr(*envp, '=')) {
setvareq(*envp, VEXPORT|VTEXTFIXED);
}
}
}
#endif
/*
* This routine initializes the builtin variables. It is called when the
* shell is initialized and again when a shell procedure is spawned.
*/
void
initvar() {
const struct varinit *ip;
struct var *vp;
struct var **vpp;
for (ip = varinit ; (vp = ip->var) != NULL ; ip++) {
if ((vp->flags & VEXPORT) == 0) {
vpp = hashvar(ip->text);
vp->next = *vpp;
*vpp = vp;
vp->text = ip->text;
vp->flags = ip->flags;
}
}
/*
* PS1 depends on uid
*/
if ((vps1.flags & VEXPORT) == 0) {
vpp = hashvar("PS1=");
vps1.next = *vpp;
*vpp = &vps1;
vps1.text = geteuid() ? "PS1=$ " : "PS1=# ";
vps1.flags = VSTRFIXED|VTEXTFIXED;
}
}
/*
* Set the value of a variable. The flags argument is ored with the
* flags of the variable. If val is NULL, the variable is unset.
*/
void
setvar(name, val, flags)
char *name, *val;
int flags;
{
char *p, *q;
int len;
int namelen;
char *nameeq;
int isbad;
isbad = 0;
p = name;
if (! is_name(*p))
isbad = 1;
p++;
for (;;) {
if (! is_in_name(*p)) {
if (*p == '\0' || *p == '=')
break;
isbad = 1;
}
p++;
}
namelen = p - name;
if (isbad)
error("%.*s: bad variable name", namelen, name);
len = namelen + 2; /* 2 is space for '=' and '\0' */
if (val == NULL) {
flags |= VUNSET;
} else {
len += strlen(val);
}
p = nameeq = ckmalloc(len);
q = name;
while (--namelen >= 0)
*p++ = *q++;
*p++ = '=';
*p = '\0';
if (val)
scopy(val, p);
setvareq(nameeq, flags);
}
STATIC int
localevar(s)
char *s;
{
static char *lnames[7] = {
"ALL", "COLLATE", "CTYPE", "MONETARY",
"NUMERIC", "TIME", NULL
};
char **ss;
if (*s != 'L')
return 0;
if (varequal(s + 1, "ANG"))
return 1;
if (strncmp(s + 1, "C_", 2) != 0)
return 0;
for (ss = lnames; *ss ; ss++)
if (varequal(s + 3, *ss))
return 1;
return 0;
}
/*
* Same as setvar except that the variable and value are passed in
* the first argument as name=value. Since the first argument will
* be actually stored in the table, it should not be a string that
* will go away.
*/
void
setvareq(s, flags)
char *s;
int flags;
{
struct var *vp, **vpp;
vpp = hashvar(s);
for (vp = *vpp ; vp ; vp = vp->next) {
if (varequal(s, vp->text)) {
if (vp->flags & VREADONLY) {
int len = strchr(s, '=') - s;
error("%.*s: is read only", len, s);
}
INTOFF;
if (vp == &vpath)
changepath(s + 5); /* 5 = strlen("PATH=") */
if ((vp->flags & (VTEXTFIXED|VSTACK)) == 0)
ckfree(vp->text);
vp->flags &=~ (VTEXTFIXED|VSTACK|VUNSET);
vp->flags |= flags;
vp->text = s;
if (vp == &vmpath || (vp == &vmail && ! mpathset()))
chkmail(1);
#ifndef NO_HISTORY
if (vp == &vhistsize)
sethistsize();
#endif
if ((vp->flags & VEXPORT) && localevar(s)) {
putenv(s);
(void) setlocale(LC_ALL, "");
}
INTON;
return;
}
}
/* not found */
vp = ckmalloc(sizeof (*vp));
vp->flags = flags;
vp->text = s;
vp->next = *vpp;
INTOFF;
*vpp = vp;
if ((vp->flags & VEXPORT) && localevar(s)) {
putenv(s);
(void) setlocale(LC_ALL, "");
}
INTON;
}
/*
* Process a linked list of variable assignments.
*/
void
listsetvar(list)
struct strlist *list;
{
struct strlist *lp;
INTOFF;
for (lp = list ; lp ; lp = lp->next) {
setvareq(savestr(lp->text), 0);
}
INTON;
}
/*
* Find the value of a variable. Returns NULL if not set.
*/
char *
lookupvar(name)
char *name;
{
struct var *v;
for (v = *hashvar(name) ; v ; v = v->next) {
if (varequal(v->text, name)) {
if (v->flags & VUNSET)
return NULL;
return strchr(v->text, '=') + 1;
}
}
return NULL;
}
/*
* Search the environment of a builtin command. If the second argument
* is nonzero, return the value of a variable even if it hasn't been
* exported.
*/
char *
bltinlookup(name, doall)
char *name;
int doall;
{
struct strlist *sp;
struct var *v;
for (sp = cmdenviron ; sp ; sp = sp->next) {
if (varequal(sp->text, name))
return strchr(sp->text, '=') + 1;
}
for (v = *hashvar(name) ; v ; v = v->next) {
if (varequal(v->text, name)) {
if ((v->flags & VUNSET)
|| (!doall && (v->flags & VEXPORT) == 0))
return NULL;
return strchr(v->text, '=') + 1;
}
}
return NULL;
}
/*
* Generate a list of exported variables. This routine is used to construct
* the third argument to execve when executing a program.
*/
char **
environment() {
int nenv;
struct var **vpp;
struct var *vp;
char **env, **ep;
nenv = 0;
for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
for (vp = *vpp ; vp ; vp = vp->next)
if (vp->flags & VEXPORT)
nenv++;
}
ep = env = stalloc((nenv + 1) * sizeof *env);
for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
for (vp = *vpp ; vp ; vp = vp->next)
if (vp->flags & VEXPORT)
*ep++ = vp->text;
}
*ep = NULL;
return env;
}
/*
* Called when a shell procedure is invoked to clear out nonexported
* variables. It is also necessary to reallocate variables of with
* VSTACK set since these are currently allocated on the stack.
*/
#ifdef mkinit
MKINIT void shprocvar();
SHELLPROC {
shprocvar();
}
#endif
void
shprocvar() {
struct var **vpp;
struct var *vp, **prev;
for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
for (prev = vpp ; (vp = *prev) != NULL ; ) {
if ((vp->flags & VEXPORT) == 0) {
*prev = vp->next;
if ((vp->flags & VTEXTFIXED) == 0)
ckfree(vp->text);
if ((vp->flags & VSTRFIXED) == 0)
ckfree(vp);
} else {
if (vp->flags & VSTACK) {
vp->text = savestr(vp->text);
vp->flags &=~ VSTACK;
}
prev = &vp->next;
}
}
}
initvar();
}
/*
* Command to list all variables which are set. Currently this command
* is invoked from the set command when the set command is called without
* any variables.
*/
int
showvarscmd(argc, argv)
int argc;
char **argv;
{
struct var **vpp;
struct var *vp;
for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
for (vp = *vpp ; vp ; vp = vp->next) {
if ((vp->flags & VUNSET) == 0)
out1fmt("%s\n", vp->text);
}
}
return 0;
}
/*
* The export and readonly commands.
*/
int
exportcmd(argc, argv)
int argc;
char **argv;
{
struct var **vpp;
struct var *vp;
char *name;
char *p;
int flag = argv[0][0] == 'r'? VREADONLY : VEXPORT;
listsetvar(cmdenviron);
if (argc > 1) {
while ((name = *argptr++) != NULL) {
if ((p = strchr(name, '=')) != NULL) {
p++;
} else {
vpp = hashvar(name);
for (vp = *vpp ; vp ; vp = vp->next) {
if (varequal(vp->text, name)) {
vp->flags |= flag;
if ((vp->flags & VEXPORT) && localevar(vp->text)) {
putenv(vp->text);
(void) setlocale(LC_ALL, "");
}
goto found;
}
}
}
setvar(name, p, flag);
found:;
}
} else {
for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
for (vp = *vpp ; vp ; vp = vp->next) {
if (vp->flags & flag) {
for (p = vp->text ; *p != '=' ; p++)
out1c(*p);
out1c('\n');
}
}
}
}
return 0;
}
/*
* The "local" command.
*/
int
localcmd(argc, argv)
int argc;
char **argv;
{
char *name;
if (! in_function())
error("Not in a function");
while ((name = *argptr++) != NULL) {
mklocal(name);
}
return 0;
}
/*
* Make a variable a local variable. When a variable is made local, it's
* value and flags are saved in a localvar structure. The saved values
* will be restored when the shell function returns. We handle the name
* "-" as a special case.
*/
void
mklocal(name)
char *name;
{
struct localvar *lvp;
struct var **vpp;
struct var *vp;
INTOFF;
lvp = ckmalloc(sizeof (struct localvar));
if (name[0] == '-' && name[1] == '\0') {
lvp->text = ckmalloc(sizeof optlist);
memcpy(lvp->text, optlist, sizeof optlist);
vp = NULL;
} else {
vpp = hashvar(name);
for (vp = *vpp ; vp && ! varequal(vp->text, name) ; vp = vp->next);
if (vp == NULL) {
if (strchr(name, '='))
setvareq(savestr(name), VSTRFIXED);
else
setvar(name, NULL, VSTRFIXED);
vp = *vpp; /* the new variable */
lvp->text = NULL;
lvp->flags = VUNSET;
} else {
lvp->text = vp->text;
lvp->flags = vp->flags;
vp->flags |= VSTRFIXED|VTEXTFIXED;
if (strchr(name, '='))
setvareq(savestr(name), 0);
}
}
lvp->vp = vp;
lvp->next = localvars;
localvars = lvp;
INTON;
}
/*
* Called after a function returns.
*/
void
poplocalvars() {
struct localvar *lvp;
struct var *vp;
while ((lvp = localvars) != NULL) {
localvars = lvp->next;
vp = lvp->vp;
if (vp == NULL) { /* $- saved */
memcpy(optlist, lvp->text, sizeof optlist);
ckfree(lvp->text);
} else if ((lvp->flags & (VUNSET|VSTRFIXED)) == VUNSET) {
(void)unsetvar(vp->text);
} else {
if ((vp->flags & VTEXTFIXED) == 0)
ckfree(vp->text);
vp->flags = lvp->flags;
vp->text = lvp->text;
}
ckfree(lvp);
}
}
int
setvarcmd(argc, argv)
int argc;
char **argv;
{
if (argc <= 2)
return unsetcmd(argc, argv);
else if (argc == 3)
setvar(argv[1], argv[2], 0);
else
error("List assignment not implemented");
return 0;
}
/*
* The unset builtin command. We unset the function before we unset the
* variable to allow a function to be unset when there is a readonly variable
* with the same name.
*/
int
unsetcmd(argc, argv)
int argc;
char **argv;
{
char **ap;
int i;
int flg_func = 0;
int flg_var = 0;
int ret = 0;
while ((i = nextopt("vf")) != '\0') {
if (i == 'f')
flg_func = 1;
else
flg_var = 1;
}
if (flg_func == 0 && flg_var == 0)
flg_var = 1;
for (ap = argptr; *ap ; ap++) {
if (flg_func)
ret |= unsetfunc(*ap);
if (flg_var)
ret |= unsetvar(*ap);
}
return ret;
}
/*
* Unset the specified variable.
*/
STATIC int
unsetvar(s)
char *s;
{
struct var **vpp;
struct var *vp;
vpp = hashvar(s);
for (vp = *vpp ; vp ; vpp = &vp->next, vp = *vpp) {
if (varequal(vp->text, s)) {
if (vp->flags & VREADONLY)
return (1);
INTOFF;
if (*(strchr(vp->text, '=') + 1) != '\0')
setvar(s, nullstr, 0);
if ((vp->flags & VEXPORT) && localevar(vp->text)) {
unsetenv(s);
setlocale(LC_ALL, "");
}
vp->flags &=~ VEXPORT;
vp->flags |= VUNSET;
if ((vp->flags & VSTRFIXED) == 0) {
if ((vp->flags & VTEXTFIXED) == 0)
ckfree(vp->text);
*vpp = vp->next;
ckfree(vp);
}
INTON;
return (0);
}
}
return (1);
}
/*
* Find the appropriate entry in the hash table from the name.
*/
STATIC struct var **
hashvar(p)
register char *p;
{
unsigned int hashval;
hashval = ((unsigned char)*p) << 4;
while (*p && *p != '=')
hashval += (unsigned char)*p++;
return &vartab[hashval % VTABSIZE];
}
/*
* Returns true if the two strings specify the same varable. The first
* variable name is terminated by '='; the second may be terminated by
* either '=' or '\0'.
*/
STATIC int
varequal(p, q)
register char *p, *q;
{
while (*p == *q++) {
if (*p++ == '=')
return 1;
}
if (*p == '=' && *(q - 1) == '\0')
return 1;
return 0;
}