390 lines
11 KiB
C
390 lines
11 KiB
C
/* Copyright (C) 1992, 1995-2003, 2005-2023 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
This file is free software: you can redistribute it and/or modify
|
|
it under the terms of the GNU Lesser General Public License as
|
|
published by the Free Software Foundation; either version 2.1 of the
|
|
License, or (at your option) any later version.
|
|
|
|
This file is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public License
|
|
along with this program. If not, see <https://www.gnu.org/licenses/>. */
|
|
|
|
#if !_LIBC
|
|
/* Don't use __attribute__ __nonnull__ in this compilation unit. Otherwise gcc
|
|
optimizes away the name == NULL test below. */
|
|
# define _GL_ARG_NONNULL(params)
|
|
|
|
# define _GL_USE_STDLIB_ALLOC 1
|
|
# include <config.h>
|
|
#endif
|
|
|
|
#include <alloca.h>
|
|
|
|
/* Specification. */
|
|
#include <stdlib.h>
|
|
|
|
#include <errno.h>
|
|
#ifndef __set_errno
|
|
# define __set_errno(ev) ((errno) = (ev))
|
|
#endif
|
|
|
|
#include <string.h>
|
|
#if _LIBC || HAVE_UNISTD_H
|
|
# include <unistd.h>
|
|
#endif
|
|
|
|
#if !_LIBC
|
|
# include "malloca.h"
|
|
#endif
|
|
|
|
#if _LIBC || !HAVE_SETENV
|
|
|
|
#if !_LIBC
|
|
# define __environ environ
|
|
#endif
|
|
|
|
#if _LIBC
|
|
/* This lock protects against simultaneous modifications of 'environ'. */
|
|
# include <bits/libc-lock.h>
|
|
__libc_lock_define_initialized (static, envlock)
|
|
# define LOCK __libc_lock_lock (envlock)
|
|
# define UNLOCK __libc_lock_unlock (envlock)
|
|
#else
|
|
# define LOCK
|
|
# define UNLOCK
|
|
#endif
|
|
|
|
/* In the GNU C library we must keep the namespace clean. */
|
|
#ifdef _LIBC
|
|
# define setenv __setenv
|
|
# define clearenv __clearenv
|
|
# define tfind __tfind
|
|
# define tsearch __tsearch
|
|
#endif
|
|
|
|
/* In the GNU C library implementation we try to be more clever and
|
|
allow arbitrarily many changes of the environment given that the used
|
|
values are from a small set. Outside glibc this will eat up all
|
|
memory after a while. */
|
|
#if defined _LIBC || (defined HAVE_SEARCH_H && defined HAVE_TSEARCH \
|
|
&& (defined __GNUC__ || defined __clang__))
|
|
# define USE_TSEARCH 1
|
|
# include <search.h>
|
|
typedef int (*compar_fn_t) (const void *, const void *);
|
|
|
|
/* This is a pointer to the root of the search tree with the known
|
|
values. */
|
|
static void *known_values;
|
|
|
|
# define KNOWN_VALUE(Str) \
|
|
({ \
|
|
void *value = tfind (Str, &known_values, (compar_fn_t) strcmp); \
|
|
value != NULL ? *(char **) value : NULL; \
|
|
})
|
|
# define STORE_VALUE(Str) \
|
|
tsearch (Str, &known_values, (compar_fn_t) strcmp)
|
|
|
|
#else
|
|
# undef USE_TSEARCH
|
|
|
|
# define KNOWN_VALUE(Str) NULL
|
|
# define STORE_VALUE(Str) do { } while (0)
|
|
|
|
#endif
|
|
|
|
|
|
/* If this variable is not a null pointer we allocated the current
|
|
environment. */
|
|
static char **last_environ;
|
|
|
|
|
|
/* This function is used by 'setenv' and 'putenv'. The difference between
|
|
the two functions is that for the former must create a new string which
|
|
is then placed in the environment, while the argument of 'putenv'
|
|
must be used directly. This is all complicated by the fact that we try
|
|
to reuse values once generated for a 'setenv' call since we can never
|
|
free the strings. */
|
|
int
|
|
__add_to_environ (const char *name, const char *value, const char *combined,
|
|
int replace)
|
|
{
|
|
char **ep;
|
|
size_t size;
|
|
const size_t namelen = strlen (name);
|
|
const size_t vallen = value != NULL ? strlen (value) + 1 : 0;
|
|
|
|
LOCK;
|
|
|
|
/* We have to get the pointer now that we have the lock and not earlier
|
|
since another thread might have created a new environment. */
|
|
ep = __environ;
|
|
|
|
size = 0;
|
|
if (ep != NULL)
|
|
{
|
|
for (; *ep != NULL; ++ep)
|
|
if (!strncmp (*ep, name, namelen) && (*ep)[namelen] == '=')
|
|
break;
|
|
else
|
|
++size;
|
|
}
|
|
|
|
if (ep == NULL || *ep == NULL)
|
|
{
|
|
char **new_environ;
|
|
#ifdef USE_TSEARCH
|
|
char *new_value;
|
|
#endif
|
|
|
|
/* We allocated this space; we can extend it. */
|
|
new_environ =
|
|
(char **) (last_environ == NULL
|
|
? malloc ((size + 2) * sizeof (char *))
|
|
: realloc (last_environ, (size + 2) * sizeof (char *)));
|
|
if (new_environ == NULL)
|
|
{
|
|
/* It's easier to set errno to ENOMEM than to rely on the
|
|
'malloc-posix' and 'realloc-posix' gnulib modules. */
|
|
__set_errno (ENOMEM);
|
|
UNLOCK;
|
|
return -1;
|
|
}
|
|
|
|
/* If the whole entry is given add it. */
|
|
if (combined != NULL)
|
|
/* We must not add the string to the search tree since it belongs
|
|
to the user. */
|
|
new_environ[size] = (char *) combined;
|
|
else
|
|
{
|
|
/* See whether the value is already known. */
|
|
#ifdef USE_TSEARCH
|
|
# ifdef _LIBC
|
|
new_value = (char *) alloca (namelen + 1 + vallen);
|
|
__mempcpy (__mempcpy (__mempcpy (new_value, name, namelen), "=", 1),
|
|
value, vallen);
|
|
# else
|
|
new_value = (char *) malloca (namelen + 1 + vallen);
|
|
if (new_value == NULL)
|
|
{
|
|
__set_errno (ENOMEM);
|
|
UNLOCK;
|
|
return -1;
|
|
}
|
|
memcpy (new_value, name, namelen);
|
|
new_value[namelen] = '=';
|
|
memcpy (&new_value[namelen + 1], value, vallen);
|
|
# endif
|
|
|
|
new_environ[size] = KNOWN_VALUE (new_value);
|
|
if (new_environ[size] == NULL)
|
|
#endif
|
|
{
|
|
new_environ[size] = (char *) malloc (namelen + 1 + vallen);
|
|
if (new_environ[size] == NULL)
|
|
{
|
|
#if defined USE_TSEARCH && !defined _LIBC
|
|
freea (new_value);
|
|
#endif
|
|
__set_errno (ENOMEM);
|
|
UNLOCK;
|
|
return -1;
|
|
}
|
|
|
|
#ifdef USE_TSEARCH
|
|
memcpy (new_environ[size], new_value, namelen + 1 + vallen);
|
|
#else
|
|
memcpy (new_environ[size], name, namelen);
|
|
new_environ[size][namelen] = '=';
|
|
memcpy (&new_environ[size][namelen + 1], value, vallen);
|
|
#endif
|
|
/* And save the value now. We cannot do this when we remove
|
|
the string since then we cannot decide whether it is a
|
|
user string or not. */
|
|
STORE_VALUE (new_environ[size]);
|
|
}
|
|
#if defined USE_TSEARCH && !defined _LIBC
|
|
freea (new_value);
|
|
#endif
|
|
}
|
|
|
|
if (__environ != last_environ)
|
|
memcpy ((char *) new_environ, (char *) __environ,
|
|
size * sizeof (char *));
|
|
|
|
new_environ[size + 1] = NULL;
|
|
|
|
last_environ = __environ = new_environ;
|
|
}
|
|
else if (replace)
|
|
{
|
|
char *np;
|
|
|
|
/* Use the user string if given. */
|
|
if (combined != NULL)
|
|
np = (char *) combined;
|
|
else
|
|
{
|
|
#ifdef USE_TSEARCH
|
|
char *new_value;
|
|
# ifdef _LIBC
|
|
new_value = alloca (namelen + 1 + vallen);
|
|
__mempcpy (__mempcpy (__mempcpy (new_value, name, namelen), "=", 1),
|
|
value, vallen);
|
|
# else
|
|
new_value = malloca (namelen + 1 + vallen);
|
|
if (new_value == NULL)
|
|
{
|
|
__set_errno (ENOMEM);
|
|
UNLOCK;
|
|
return -1;
|
|
}
|
|
memcpy (new_value, name, namelen);
|
|
new_value[namelen] = '=';
|
|
memcpy (&new_value[namelen + 1], value, vallen);
|
|
# endif
|
|
|
|
np = KNOWN_VALUE (new_value);
|
|
if (np == NULL)
|
|
#endif
|
|
{
|
|
np = (char *) malloc (namelen + 1 + vallen);
|
|
if (np == NULL)
|
|
{
|
|
#if defined USE_TSEARCH && !defined _LIBC
|
|
freea (new_value);
|
|
#endif
|
|
__set_errno (ENOMEM);
|
|
UNLOCK;
|
|
return -1;
|
|
}
|
|
|
|
#ifdef USE_TSEARCH
|
|
memcpy (np, new_value, namelen + 1 + vallen);
|
|
#else
|
|
memcpy (np, name, namelen);
|
|
np[namelen] = '=';
|
|
memcpy (&np[namelen + 1], value, vallen);
|
|
#endif
|
|
/* And remember the value. */
|
|
STORE_VALUE (np);
|
|
}
|
|
#if defined USE_TSEARCH && !defined _LIBC
|
|
freea (new_value);
|
|
#endif
|
|
}
|
|
|
|
*ep = np;
|
|
}
|
|
|
|
UNLOCK;
|
|
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
setenv (const char *name, const char *value, int replace)
|
|
{
|
|
if (name == NULL || *name == '\0' || strchr (name, '=') != NULL)
|
|
{
|
|
__set_errno (EINVAL);
|
|
return -1;
|
|
}
|
|
|
|
return __add_to_environ (name, value, NULL, replace);
|
|
}
|
|
|
|
/* The 'clearenv' was planned to be added to POSIX.1 but probably
|
|
never made it. Nevertheless the POSIX.9 standard (POSIX bindings
|
|
for Fortran 77) requires this function. */
|
|
int
|
|
clearenv (void)
|
|
{
|
|
LOCK;
|
|
|
|
if (__environ == last_environ && __environ != NULL)
|
|
{
|
|
/* We allocated this environment so we can free it. */
|
|
free (__environ);
|
|
last_environ = NULL;
|
|
}
|
|
|
|
/* Clear the environment pointer removes the whole environment. */
|
|
__environ = NULL;
|
|
|
|
UNLOCK;
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef _LIBC
|
|
static void
|
|
free_mem (void)
|
|
{
|
|
/* Remove all traces. */
|
|
clearenv ();
|
|
|
|
/* Now remove the search tree. */
|
|
__tdestroy (known_values, free);
|
|
known_values = NULL;
|
|
}
|
|
text_set_element (__libc_subfreeres, free_mem);
|
|
|
|
|
|
# undef setenv
|
|
# undef clearenv
|
|
weak_alias (__setenv, setenv)
|
|
weak_alias (__clearenv, clearenv)
|
|
#endif
|
|
|
|
#endif /* _LIBC || !HAVE_SETENV */
|
|
|
|
/* The rest of this file is called into use when replacing an existing
|
|
but buggy setenv. Known bugs include failure to diagnose invalid
|
|
name, and consuming a leading '=' from value. */
|
|
#if HAVE_SETENV
|
|
|
|
# undef setenv
|
|
# if !HAVE_DECL_SETENV
|
|
extern int setenv (const char *, const char *, int);
|
|
# endif
|
|
# define STREQ(a, b) (strcmp (a, b) == 0)
|
|
|
|
int
|
|
rpl_setenv (const char *name, const char *value, int replace)
|
|
{
|
|
int result;
|
|
if (!name || !*name || strchr (name, '='))
|
|
{
|
|
errno = EINVAL;
|
|
return -1;
|
|
}
|
|
/* Call the real setenv even if replace is 0, in case implementation
|
|
has underlying data to update, such as when environ changes. */
|
|
result = setenv (name, value, replace);
|
|
if (result == 0 && replace && *value == '=')
|
|
{
|
|
char *tmp = getenv (name);
|
|
if (!STREQ (tmp, value))
|
|
{
|
|
int saved_errno;
|
|
size_t len = strlen (value);
|
|
tmp = malloca (len + 2);
|
|
/* Since leading '=' is eaten, double it up. */
|
|
*tmp = '=';
|
|
memcpy (tmp + 1, value, len + 1);
|
|
result = setenv (name, tmp, replace);
|
|
saved_errno = errno;
|
|
freea (tmp);
|
|
errno = saved_errno;
|
|
}
|
|
}
|
|
return result;
|
|
}
|
|
|
|
#endif /* HAVE_SETENV */
|