glibc/sysdeps/nacl/nacl-interfaces.h
Adhemerval Zanella afcf3cd8eb New internal function __access_noerrno
Implement an internal version of __access called __access_noerrno that
avoids setting errno.  This is useful to check accessibility of files
very early on in process startup i.e. before TLS setup.  This allows
tunables to replace MALLOC_CHECK_ safely (i.e. check existence of
/etc/suid-debug to enable/disable MALLOC_CHECK) and at the same time
initialize very early so that it can override IFUNCs.

Checked on x86_64.

	* hurd/hurd.h (__hurd_fail_noerrno): New function.
	* include/unistd.h [IS_IN (rtld) || !defined SHARED]: Declare
	__access_noerrno.
	* io/access.c (__access_noerrno): New function.
	* sysdeps/mach/hurd/access.c (hurd_fail_seterrno): New function.
	(hurd_fail_seterrno): Likewise.
	(access_common): Likewise.
	(__access_noerrno): Likewise.
	* sysdeps/nacl/access.c (__access_noerrno): Likewise.
	* sysdeps/unix/sysv/linux/access.c (__access_noerrno): Likewise.
	* sysdeps/nacl/nacl-interfaces.h (NACL_CALL_NOERRNO): New
	macro.
2016-11-16 15:53:58 -02:00

121 lines
3.9 KiB
C

/* Using NaCl interface tables.
Copyright (C) 2015-2016 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library 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.
The GNU C Library 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 the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#ifndef _NACL_INTERFACES_H
#define _NACL_INTERFACES_H 1
#include <errno.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include <sys/types.h>
/* <nacl-irt.h> is massaged from native_client/src/untrusted/irt/irt.h so
that it uses nacl_abi_*_t type names. We must define those types first. */
/* These are the same in the IRT ABI as in the libc ABI. */
typedef blksize_t nacl_abi_blksize_t;
typedef dev_t nacl_abi_dev_t;
typedef gid_t nacl_abi_gid_t;
typedef ino_t nacl_abi_ino_t;
typedef mode_t nacl_abi_mode_t;
typedef nlink_t nacl_abi_nlink_t;
typedef size_t nacl_abi_size_t;
typedef time_t nacl_abi_time_t;
typedef uid_t nacl_abi_uid_t;
typedef struct dirent nacl_abi_dirent_t;
typedef struct timeval nacl_abi_timeval_t;
typedef struct timespec nacl_abi_timespec_t;
/* This is unsigned in the IRT ABI, but it's traditionally 'long int',
so we stick with that. */
typedef clock_t nacl_abi_clock_t;
typedef int32_t nacl_abi_blkcnt_t;
/* This is different by design. */
typedef struct nacl_abi_stat nacl_abi_stat_t;
#include <nacl-irt.h>
/* This is how we access the IRT interface-query function.
This formulation makes it usable as if it were a function name. */
#define __nacl_irt_query (*(TYPE_nacl_irt_query) GLRO(dl_sysinfo))
/* This describes one IRT (or IRT-like) interface that libc uses.
This structure contains no pointers, so it can go into rodata
without relocs. Instead, the actual tables we use for these
interfaces live in a parallel section in writable data. */
struct nacl_interface {
size_t table_size;
size_t namelen;
char name[];
};
/* Increment for 'const struct nacl_interface *' pointers. */
static inline const struct nacl_interface *
next_nacl_interface (const struct nacl_interface *i)
{
uintptr_t align = __alignof (*i);
return (const void *) (((uintptr_t) &i->name[i->namelen] + align - 1)
& -align);
}
#if IS_IN (libpthread)
# define libpthread_hidden_proto(name) hidden_proto (name)
#else
# define libpthread_hidden_proto(name)
#endif
#define DECLARE_INTERFACE(module, type) \
extern struct type __##type; module##_hidden_proto (__##type);
#define NACL_MANDATORY_INTERFACE(module, id, type) \
DECLARE_INTERFACE (module, type)
#define NACL_OPTIONAL_INTERFACE(module, id, type) \
DECLARE_INTERFACE (module, type)
#include "nacl-interface-list.h"
#undef NACL_MANDATORY_INTERFACE
#undef NACL_OPTIONAL_INTERFACE
extern void __nacl_initialize_interfaces (void) attribute_hidden;
extern bool __nacl_supply_interface_libc (const char *ident, size_t ident_len,
const void *table, size_t tablesize)
internal_function attribute_hidden;
extern bool __nacl_supply_interface_rtld (const char *ident, size_t ident_len,
const void *table, size_t tablesize);
internal_function;
/* Convenience function for handling IRT call return values. */
static inline int
__nacl_fail (int err)
{
errno = err;
return -1;
}
#define NACL_CALL(err, val) \
({ int _err = (err); _err ? __nacl_fail (_err) : (val); })
/* Same as NACL_CALL but without setting errno. */
#define NACL_CALL_NOERRNO(err, val) \
({ int _err = (err); _err ? _err : (val); })
#endif /* nacl-interfaces.h */