freebsd-skq/lib/libc/locale/xlocale.c
David Chisnall 8d07b7deff Fix an issue where the locale and rune locale could become out of sync,
causing mb* functions (and similar) to be called with the wrong data
(possibly a null pointer, causing a crash).

PR:		standards/188036
MFC after:	1 week
2014-04-02 11:10:46 +00:00

370 lines
8.5 KiB
C

/*-
* Copyright (c) 2011 The FreeBSD Foundation
* All rights reserved.
*
* This software was developed by David Chisnall under sponsorship from
* the FreeBSD Foundation.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*
* $FreeBSD$
*/
#include <pthread.h>
#include <stdio.h>
#include <string.h>
#include <runetype.h>
#include "libc_private.h"
#include "xlocale_private.h"
/**
* Each locale loader declares a global component. This is used by setlocale()
* and also by xlocale with LC_GLOBAL_LOCALE..
*/
extern struct xlocale_component __xlocale_global_collate;
extern struct xlocale_component __xlocale_global_ctype;
extern struct xlocale_component __xlocale_global_monetary;
extern struct xlocale_component __xlocale_global_numeric;
extern struct xlocale_component __xlocale_global_time;
extern struct xlocale_component __xlocale_global_messages;
/*
* And another version for the statically-allocated C locale. We only have
* components for the parts that are expected to be sensible.
*/
extern struct xlocale_component __xlocale_C_collate;
extern struct xlocale_component __xlocale_C_ctype;
#ifndef __NO_TLS
/*
* The locale for this thread.
*/
_Thread_local locale_t __thread_locale;
#endif
/*
* Flag indicating that one or more per-thread locales exist.
*/
int __has_thread_locale;
/*
* Private functions in setlocale.c.
*/
const char *
__get_locale_env(int category);
int
__detect_path_locale(void);
struct _xlocale __xlocale_global_locale = {
{0},
{
&__xlocale_global_collate,
&__xlocale_global_ctype,
&__xlocale_global_monetary,
&__xlocale_global_numeric,
&__xlocale_global_time,
&__xlocale_global_messages
},
1,
0,
1,
0
};
struct _xlocale __xlocale_C_locale = {
{0},
{
&__xlocale_C_collate,
&__xlocale_C_ctype,
0, 0, 0, 0
},
1,
0,
1,
0
};
static void*(*constructors[])(const char*, locale_t) =
{
__collate_load,
__ctype_load,
__monetary_load,
__numeric_load,
__time_load,
__messages_load
};
static pthread_key_t locale_info_key;
static int fake_tls;
static locale_t thread_local_locale;
static void init_key(void)
{
pthread_key_create(&locale_info_key, xlocale_release);
pthread_setspecific(locale_info_key, (void*)42);
if (pthread_getspecific(locale_info_key) == (void*)42) {
pthread_setspecific(locale_info_key, 0);
} else {
fake_tls = 1;
}
/* At least one per-thread locale has now been set. */
__has_thread_locale = 1;
__detect_path_locale();
}
static pthread_once_t once_control = PTHREAD_ONCE_INIT;
static locale_t
get_thread_locale(void)
{
_once(&once_control, init_key);
return (fake_tls ? thread_local_locale :
pthread_getspecific(locale_info_key));
}
#ifdef __NO_TLS
locale_t
__get_locale(void)
{
locale_t l = get_thread_locale();
return (l ? l : &__xlocale_global_locale);
}
#endif
static void
set_thread_locale(locale_t loc)
{
locale_t l = (loc == LC_GLOBAL_LOCALE) ? 0 : loc;
_once(&once_control, init_key);
if (NULL != l) {
xlocale_retain((struct xlocale_refcounted*)l);
}
locale_t old = pthread_getspecific(locale_info_key);
if ((NULL != old) && (l != old)) {
xlocale_release((struct xlocale_refcounted*)old);
}
if (fake_tls) {
thread_local_locale = l;
} else {
pthread_setspecific(locale_info_key, l);
}
#ifndef __NO_TLS
__thread_locale = l;
__set_thread_rune_locale(loc);
#endif
}
/**
* Clean up a locale, once its reference count reaches zero. This function is
* called by xlocale_release(), it should not be called directly.
*/
static void
destruct_locale(void *l)
{
locale_t loc = l;
for (int type=0 ; type<XLC_LAST ; type++) {
if (loc->components[type]) {
xlocale_release(loc->components[type]);
}
}
if (loc->csym) {
free(loc->csym);
}
free(l);
}
/**
* Allocates a new, uninitialised, locale.
*/
static locale_t
alloc_locale(void)
{
locale_t new = calloc(sizeof(struct _xlocale), 1);
new->header.destructor = destruct_locale;
new->monetary_locale_changed = 1;
new->numeric_locale_changed = 1;
return (new);
}
static void
copyflags(locale_t new, locale_t old)
{
new->using_monetary_locale = old->using_monetary_locale;
new->using_numeric_locale = old->using_numeric_locale;
new->using_time_locale = old->using_time_locale;
new->using_messages_locale = old->using_messages_locale;
}
static int dupcomponent(int type, locale_t base, locale_t new)
{
/* Always copy from the global locale, since it has mutable components.
*/
struct xlocale_component *src = base->components[type];
if (&__xlocale_global_locale == base) {
new->components[type] = constructors[type](src->locale, new);
if (new->components[type]) {
strncpy(new->components[type]->locale, src->locale,
ENCODING_LEN);
}
} else if (base->components[type]) {
new->components[type] = xlocale_retain(base->components[type]);
} else {
/* If the component was NULL, return success - if base is a
* valid locale then the flag indicating that this isn't
* present should be set. If it isn't a valid locale, then
* we're stuck anyway. */
return 1;
}
return (0 != new->components[type]);
}
/*
* Public interfaces. These are the five public functions described by the
* xlocale interface.
*/
locale_t newlocale(int mask, const char *locale, locale_t base)
{
int type;
const char *realLocale = locale;
int useenv = 0;
int success = 1;
_once(&once_control, init_key);
locale_t new = alloc_locale();
if (NULL == new) {
return (NULL);
}
FIX_LOCALE(base);
copyflags(new, base);
if (NULL == locale) {
realLocale = "C";
} else if ('\0' == locale[0]) {
useenv = 1;
}
for (type=0 ; type<XLC_LAST ; type++) {
if (mask & 1) {
if (useenv) {
realLocale = __get_locale_env(type);
}
new->components[type] =
constructors[type](realLocale, new);
if (new->components[type]) {
strncpy(new->components[type]->locale,
realLocale, ENCODING_LEN);
} else {
success = 0;
break;
}
} else {
if (!dupcomponent(type, base, new)) {
success = 0;
break;
}
}
mask >>= 1;
}
if (0 == success) {
xlocale_release(new);
new = NULL;
}
return (new);
}
locale_t duplocale(locale_t base)
{
locale_t new = alloc_locale();
int type;
_once(&once_control, init_key);
if (NULL == new) {
return (NULL);
}
FIX_LOCALE(base);
copyflags(new, base);
for (type=0 ; type<XLC_LAST ; type++) {
dupcomponent(type, base, new);
}
return (new);
}
/*
* Free a locale_t. This is quite a poorly named function. It actually
* disclaims a reference to a locale_t, rather than freeing it.
*/
int
freelocale(locale_t loc)
{
/* Fail if we're passed something that isn't a locale. */
if ((NULL == loc) || (LC_GLOBAL_LOCALE == loc)) {
return (-1);
}
/* If we're passed the global locale, pretend that we freed it but don't
* actually do anything. */
if (&__xlocale_global_locale == loc) {
return (0);
}
xlocale_release(loc);
return (0);
}
/*
* Returns the name of the locale for a particular component of a locale_t.
*/
const char *querylocale(int mask, locale_t loc)
{
int type = ffs(mask) - 1;
FIX_LOCALE(loc);
if (type >= XLC_LAST)
return (NULL);
if (loc->components[type])
return (loc->components[type]->locale);
return ("C");
}
/*
* Installs the specified locale_t as this thread's locale.
*/
locale_t uselocale(locale_t loc)
{
locale_t old = get_thread_locale();
if (NULL != loc) {
set_thread_locale(loc);
}
return (old ? old : LC_GLOBAL_LOCALE);
}