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/*
* Copyright (C) 2014 The Android Open Source Project
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef __ANDROID_DLEXT_H__
#define __ANDROID_DLEXT_H__
#include <stddef.h>
#include <stdint.h>
#include <sys/cdefs.h>
#include <sys/types.h> /* for off64_t */
__BEGIN_DECLS
/* bitfield definitions for android_dlextinfo.flags */
enum {
/* When set, the reserved_addr and reserved_size fields must point to an
* already-reserved region of address space which will be used to load the
* library if it fits. If the reserved region is not large enough, the load
* will fail.
*/
ANDROID_DLEXT_RESERVED_ADDRESS = 0x1,
/* As DLEXT_RESERVED_ADDRESS, but if the reserved region is not large enough,
* the linker will choose an available address instead.
*/
ANDROID_DLEXT_RESERVED_ADDRESS_HINT = 0x2,
/* When set, write the GNU RELRO section of the mapped library to relro_fd
* after relocation has been performed, to allow it to be reused by another
* process loading the same library at the same address. This implies
* ANDROID_DLEXT_USE_RELRO.
*/
ANDROID_DLEXT_WRITE_RELRO = 0x4,
/* When set, compare the GNU RELRO section of the mapped library to relro_fd
* after relocation has been performed, and replace any relocated pages that
* are identical with a version mapped from the file.
*/
ANDROID_DLEXT_USE_RELRO = 0x8,
/* Instruct dlopen to use library_fd instead of opening file by name.
* The filename parameter is still used to identify the library.
*/
ANDROID_DLEXT_USE_LIBRARY_FD = 0x10,
/* If opening a library using library_fd read it starting at library_fd_offset.
* This flag is only valid when ANDROID_DLEXT_USE_LIBRARY_FD is set.
*/
ANDROID_DLEXT_USE_LIBRARY_FD_OFFSET = 0x20,
/* When set, do not check if the library has already been loaded by file stat(2)s.
*
* This flag allows forced loading of the library in the case when for some
* reason multiple ELF files share the same filename (because the already-loaded
* library has been removed and overwritten, for example).
*
* Note that if the library has the same dt_soname as an old one and some other
* library has the soname in DT_NEEDED list, the first one will be used to resolve any
* dependencies.
*/
ANDROID_DLEXT_FORCE_LOAD = 0x40,
/* Mask of valid bits */
ANDROID_DLEXT_VALID_FLAG_BITS = ANDROID_DLEXT_RESERVED_ADDRESS |
ANDROID_DLEXT_RESERVED_ADDRESS_HINT |
ANDROID_DLEXT_WRITE_RELRO |
ANDROID_DLEXT_USE_RELRO |
ANDROID_DLEXT_USE_LIBRARY_FD |
ANDROID_DLEXT_USE_LIBRARY_FD_OFFSET |
ANDROID_DLEXT_FORCE_LOAD,
};
typedef struct {
uint64_t flags;
void* reserved_addr;
size_t reserved_size;
int relro_fd;
int library_fd;
off64_t library_fd_offset;
} android_dlextinfo;
extern void* android_dlopen_ext(const char* filename, int flag, const android_dlextinfo* extinfo);
__END_DECLS
#endif /* __ANDROID_DLEXT_H__ */
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