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/*
* Copyright (C) 2008 The Android Open Source Project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * 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 COPYRIGHT HOLDERS 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
* COPYRIGHT OWNER 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 _LINKER_H_
#define _LINKER_H_
#include <unistd.h>
#include <sys/types.h>
#include <elf.h>
#include <sys/exec_elf.h>
#include <link.h>
// Returns the address of the page containing address 'x'.
#define PAGE_START(x) ((x) & PAGE_MASK)
// Returns the offset of address 'x' in its page.
#define PAGE_OFFSET(x) ((x) & ~PAGE_MASK)
// Returns the address of the next page after address 'x', unless 'x' is
// itself at the start of a page.
#define PAGE_END(x) PAGE_START((x) + (PAGE_SIZE-1))
// Magic shared structures that GDB knows about.
struct link_map {
uintptr_t l_addr;
char* l_name;
uintptr_t l_ld;
struct link_map* l_next;
struct link_map* l_prev;
};
// Values for r_debug->state
enum {
RT_CONSISTENT,
RT_ADD,
RT_DELETE
};
struct r_debug {
int32_t r_version;
struct link_map* r_map;
void (*r_brk)(void);
int32_t r_state;
uintptr_t r_ldbase;
};
#define FLAG_LINKED 0x00000001
#define FLAG_EXE 0x00000004 // The main executable
#define FLAG_LINKER 0x00000010 // The linker itself
#define SOINFO_NAME_LEN 128
struct soinfo {
char name[SOINFO_NAME_LEN];
const Elf32_Phdr* phdr;
int phnum;
unsigned entry;
unsigned base;
unsigned size;
int unused; // DO NOT USE, maintained for compatibility.
Elf32_Dyn* dynamic;
unsigned unused2; // DO NOT USE, maintained for compatibility
unsigned unused3; // DO NOT USE, maintained for compatibility
soinfo* next;
unsigned flags;
const char* strtab;
Elf32_Sym* symtab;
unsigned nbucket;
unsigned nchain;
unsigned* bucket;
unsigned* chain;
unsigned* plt_got;
Elf32_Rel* plt_rel;
unsigned plt_rel_count;
Elf32_Rel* rel;
unsigned rel_count;
unsigned* preinit_array;
unsigned preinit_array_count;
unsigned* init_array;
unsigned init_array_count;
unsigned* fini_array;
unsigned fini_array_count;
void (*init_func)();
void (*fini_func)();
#if defined(ANDROID_ARM_LINKER)
// ARM EABI section used for stack unwinding.
unsigned* ARM_exidx;
unsigned ARM_exidx_count;
#elif defined(ANDROID_MIPS_LINKER)
unsigned mips_symtabno;
unsigned mips_local_gotno;
unsigned mips_gotsym;
#endif
unsigned refcount;
struct link_map linkmap;
bool constructors_called;
// When you read a virtual address from the ELF file, add this
// value to get the corresponding address in the process' address space.
Elf32_Addr load_bias;
bool has_text_relocations;
bool has_DT_SYMBOLIC;
void CallConstructors();
void CallDestructors();
void CallPreInitConstructors();
private:
void CallArray(const char* array_name, unsigned* array, int count, bool reverse);
void CallFunction(const char* function_name, void (*function)());
};
extern soinfo libdl_info;
// These aren't defined in <sys/exec_elf.h>.
#ifndef DT_PREINIT_ARRAY
#define DT_PREINIT_ARRAY 32
#endif
#ifndef DT_PREINIT_ARRAYSZ
#define DT_PREINIT_ARRAYSZ 33
#endif
void do_android_update_LD_LIBRARY_PATH(const char* ld_library_path);
soinfo* do_dlopen(const char* name, int flags);
int do_dlclose(soinfo* si);
Elf32_Sym* dlsym_linear_lookup(const char* name, soinfo** found, soinfo* start);
soinfo* find_containing_library(const void* addr);
const char* linker_get_error();
Elf32_Sym* dladdr_find_symbol(soinfo* si, const void* addr);
Elf32_Sym* dlsym_handle_lookup(soinfo* si, const char* name);
void debuggerd_init();
extern "C" void notify_gdb_of_libraries();
#endif
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