Sean Farley 2966d28c32 Significantly reduce the memory leak as noted in BUGS section for
setenv(3) by tracking the size of the memory allocated instead of using
strlen() on the current value.

Convert all calls to POSIX from historic BSD API:
 - unsetenv returns an int.
 - putenv takes a char * instead of const char *.
 - putenv no longer makes a copy of the input string.
 - errno is set appropriately for POSIX.  Exceptions involve bad environ
   variable and internal initialization code.  These both set errno to
   EFAULT.

Several patches to base utilities to handle the POSIX changes from
Andrey Chernov's previous commit.  A few I re-wrote to use setenv()
instead of putenv().

New regression module for tools/regression/environ to test these
functions.  It also can be used to test the performance.

Bump __FreeBSD_version to 700050 due to API change.

PR:		kern/99826
Approved by:	wes
Approved by:	re (kensmith)
2007-07-04 00:00:41 +00:00

856 lines
16 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.
* 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.
*/
#ifndef lint
#if 0
static char sccsid[] = "@(#)var.c 8.3 (Berkeley) 5/4/95";
#endif
#endif /* not lint */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <unistd.h>
#include <stdlib.h>
#include <paths.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 "var.h"
#include "memalloc.h"
#include "error.h"
#include "mystring.h"
#include "parser.h"
#ifndef NO_HISTORY
#include "myhistedit.h"
#endif
#define VTABSIZE 39
struct varinit {
struct var *var;
int flags;
char *text;
void (*func)(const char *);
};
#ifndef NO_HISTORY
struct var vhistsize;
#endif
struct var vifs;
struct var vmail;
struct var vmpath;
struct var vpath;
struct var vppid;
struct var vps1;
struct var vps2;
struct var vps4;
struct var vvers;
STATIC struct var voptind;
STATIC const struct varinit varinit[] = {
#ifndef NO_HISTORY
{ &vhistsize, VSTRFIXED|VTEXTFIXED|VUNSET, "HISTSIZE=",
sethistsize },
#endif
{ &vifs, VSTRFIXED|VTEXTFIXED, "IFS= \t\n",
NULL },
{ &vmail, VSTRFIXED|VTEXTFIXED|VUNSET, "MAIL=",
NULL },
{ &vmpath, VSTRFIXED|VTEXTFIXED|VUNSET, "MAILPATH=",
NULL },
{ &vpath, VSTRFIXED|VTEXTFIXED, "PATH=" _PATH_DEFPATH,
changepath },
{ &vppid, VSTRFIXED|VTEXTFIXED|VUNSET, "PPID=",
NULL },
/*
* vps1 depends on uid
*/
{ &vps2, VSTRFIXED|VTEXTFIXED, "PS2=> ",
NULL },
{ &vps4, VSTRFIXED|VTEXTFIXED, "PS4=+ ",
NULL },
{ &voptind, VSTRFIXED|VTEXTFIXED, "OPTIND=1",
getoptsreset },
{ NULL, 0, NULL,
NULL }
};
STATIC struct var *vartab[VTABSIZE];
STATIC struct var **hashvar(char *);
STATIC int varequal(char *, char *);
STATIC int localevar(char *);
/*
* Initialize the variable 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(void)
{
char ppid[20];
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;
vp->func = ip->func;
}
}
/*
* 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;
}
if ((vppid.flags & VEXPORT) == 0) {
fmtstr(ppid, sizeof(ppid), "%d", (int)getppid());
setvarsafe("PPID", ppid, 0);
}
}
/*
* Safe version of setvar, returns 1 on success 0 on failure.
*/
int
setvarsafe(char *name, char *val, int flags)
{
struct jmploc jmploc;
struct jmploc *volatile savehandler = handler;
int err = 0;
#if __GNUC__
/* Avoid longjmp clobbering */
(void) &err;
#endif
if (setjmp(jmploc.loc))
err = 1;
else {
handler = &jmploc;
setvar(name, val, flags);
}
handler = savehandler;
return err;
}
/*
* Set the value of a variable. The flags argument is stored with the
* flags of the variable. If val is NULL, the variable is unset.
*/
void
setvar(char *name, char *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(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(char *s, int flags)
{
struct var *vp, **vpp;
char *p;
int len;
if (aflag)
flags |= VEXPORT;
vpp = hashvar(s);
for (vp = *vpp ; vp ; vp = vp->next) {
if (varequal(s, vp->text)) {
if (vp->flags & VREADONLY) {
len = strchr(s, '=') - s;
error("%.*s: is read only", len, s);
}
INTOFF;
if (vp->func && (flags & VNOFUNC) == 0)
(*vp->func)(strchr(s, '=') + 1);
if ((vp->flags & (VTEXTFIXED|VSTACK)) == 0)
ckfree(vp->text);
vp->flags &= ~(VTEXTFIXED|VSTACK|VUNSET);
vp->flags |= flags;
vp->text = s;
/*
* We could roll this to a function, to handle it as
* a regular variable function callback, but why bother?
*/
if (vp == &vmpath || (vp == &vmail && ! mpathset()))
chkmail(1);
if ((vp->flags & VEXPORT) && localevar(s)) {
p = strchr(s, '=');
*p = '\0';
(void) setenv(s, p + 1, 1);
*p = '=';
(void) setlocale(LC_ALL, "");
}
INTON;
return;
}
}
/* not found */
vp = ckmalloc(sizeof (*vp));
vp->flags = flags;
vp->text = s;
vp->next = *vpp;
vp->func = NULL;
INTOFF;
*vpp = vp;
if ((vp->flags & VEXPORT) && localevar(s)) {
p = strchr(s, '=');
*p = '\0';
(void) setenv(s, p + 1, 1);
*p = '=';
(void) setlocale(LC_ALL, "");
}
INTON;
}
/*
* Process a linked list of variable assignments.
*/
void
listsetvar(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(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(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(void)
{
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(void);
SHELLPROC {
shprocvar();
}
#endif
void
shprocvar(void)
{
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();
}
static int
var_compare(const void *a, const void *b)
{
const char *const *sa, *const *sb;
sa = a;
sb = b;
/*
* This compares two var=value strings which creates a different
* order from what you would probably expect. POSIX is somewhat
* ambiguous on what should be sorted exactly.
*/
return strcoll(*sa, *sb);
}
/*
* 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(int argc __unused, char **argv __unused)
{
struct var **vpp;
struct var *vp;
const char *s;
const char **vars;
int i, n;
/*
* POSIX requires us to sort the variables.
*/
n = 0;
for (vpp = vartab; vpp < vartab + VTABSIZE; vpp++) {
for (vp = *vpp; vp; vp = vp->next) {
if (!(vp->flags & VUNSET))
n++;
}
}
INTON;
vars = ckmalloc(n * sizeof(*vars));
i = 0;
for (vpp = vartab; vpp < vartab + VTABSIZE; vpp++) {
for (vp = *vpp; vp; vp = vp->next) {
if (!(vp->flags & VUNSET))
vars[i++] = vp->text;
}
}
qsort(vars, n, sizeof(*vars), var_compare);
for (i = 0; i < n; i++) {
for (s = vars[i]; *s != '='; s++)
out1c(*s);
out1c('=');
out1qstr(s + 1);
out1c('\n');
}
ckfree(vars);
INTOFF;
return 0;
}
/*
* The export and readonly commands.
*/
int
exportcmd(int argc, char **argv)
{
struct var **vpp;
struct var *vp;
char *name;
char *p;
char *cmdname;
int ch, values;
int flag = argv[0][0] == 'r'? VREADONLY : VEXPORT;
cmdname = argv[0];
optreset = optind = 1;
opterr = 0;
values = 0;
while ((ch = getopt(argc, argv, "p")) != -1) {
switch (ch) {
case 'p':
values = 1;
break;
case '?':
default:
error("unknown option: -%c", optopt);
}
}
argc -= optind;
argv += optind;
if (values && argc != 0)
error("-p requires no arguments");
listsetvar(cmdenviron);
if (argc != 0) {
while ((name = *argv++) != 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)) {
p = strchr(vp->text, '=');
*p = '\0';
(void) setenv(vp->text, p + 1, 1);
*p = '=';
(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) {
if (values) {
out1str(cmdname);
out1c(' ');
}
for (p = vp->text ; *p != '=' ; p++)
out1c(*p);
if (values && !(vp->flags & VUNSET)) {
out1c('=');
out1qstr(p + 1);
}
out1c('\n');
}
}
}
}
return 0;
}
/*
* The "local" command.
*/
int
localcmd(int argc __unused, char **argv __unused)
{
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(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(void)
{
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(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(int argc __unused, char **argv __unused)
{
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.
*/
int
unsetvar(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 (0);
}
/*
* Find the appropriate entry in the hash table from the name.
*/
STATIC struct var **
hashvar(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(char *p, char *q)
{
while (*p == *q++) {
if (*p++ == '=')
return 1;
}
if (*p == '=' && *(q - 1) == '\0')
return 1;
return 0;
}