linker.h revision 7059b1f02ea9197728c851edd9ae0dd7688fa700
1/* 2 * Copyright (C) 2008 The Android Open Source Project 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in 12 * the documentation and/or other materials provided with the 13 * distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29#ifndef _LINKER_H_ 30#define _LINKER_H_ 31 32#include <unistd.h> 33#include <sys/types.h> 34#include <linux/elf.h> 35 36#undef PAGE_MASK 37#undef PAGE_SIZE 38#define PAGE_SIZE 4096 39#define PAGE_MASK 4095 40 41void debugger_init(); 42const char *addr_to_name(unsigned addr); 43 44/* magic shared structures that GDB knows about */ 45 46struct link_map 47{ 48 uintptr_t l_addr; 49 char * l_name; 50 uintptr_t l_ld; 51 struct link_map * l_next; 52 struct link_map * l_prev; 53}; 54 55/* needed for dl_iterate_phdr to be passed to the callbacks provided */ 56struct dl_phdr_info 57{ 58 Elf32_Addr dlpi_addr; 59 const char *dlpi_name; 60 const Elf32_Phdr *dlpi_phdr; 61 Elf32_Half dlpi_phnum; 62}; 63 64 65// Values for r_debug->state 66enum { 67 RT_CONSISTENT, 68 RT_ADD, 69 RT_DELETE 70}; 71 72struct r_debug 73{ 74 int32_t r_version; 75 struct link_map * r_map; 76 void (*r_brk)(void); 77 int32_t r_state; 78 uintptr_t r_ldbase; 79}; 80 81typedef struct soinfo soinfo; 82 83#define FLAG_LINKED 0x00000001 84#define FLAG_ERROR 0x00000002 85#define FLAG_EXE 0x00000004 // The main executable 86 87#define SOINFO_NAME_LEN 128 88 89struct soinfo 90{ 91 const char name[SOINFO_NAME_LEN]; 92 Elf32_Phdr *phdr; 93 int phnum; 94 unsigned entry; 95 unsigned base; 96 unsigned size; 97 98 unsigned *dynamic; 99 100 unsigned wrprotect_start; 101 unsigned wrprotect_end; 102 103 soinfo *next; 104 unsigned flags; 105 106 const char *strtab; 107 Elf32_Sym *symtab; 108 109 unsigned nbucket; 110 unsigned nchain; 111 unsigned *bucket; 112 unsigned *chain; 113 114 unsigned *plt_got; 115 116 Elf32_Rel *plt_rel; 117 unsigned plt_rel_count; 118 119 Elf32_Rel *rel; 120 unsigned rel_count; 121 122#ifdef ANDROID_SH_LINKER 123 Elf32_Rela *plt_rela; 124 unsigned plt_rela_count; 125 126 Elf32_Rela *rela; 127 unsigned rela_count; 128#endif /* ANDROID_SH_LINKER */ 129 130 unsigned *preinit_array; 131 unsigned preinit_array_count; 132 133 unsigned *init_array; 134 unsigned init_array_count; 135 unsigned *fini_array; 136 unsigned fini_array_count; 137 138 void (*init_func)(void); 139 void (*fini_func)(void); 140 141#ifdef ANDROID_ARM_LINKER 142 /* ARM EABI section used for stack unwinding. */ 143 unsigned *ARM_exidx; 144 unsigned ARM_exidx_count; 145#endif 146 147 unsigned refcount; 148 struct link_map linkmap; 149}; 150 151 152extern soinfo libdl_info; 153 154#ifdef ANDROID_ARM_LINKER 155 156#define R_ARM_COPY 20 157#define R_ARM_GLOB_DAT 21 158#define R_ARM_JUMP_SLOT 22 159#define R_ARM_RELATIVE 23 160 161/* According to the AAPCS specification, we only 162 * need the above relocations. However, in practice, 163 * the following ones turn up from time to time. 164 */ 165#define R_ARM_ABS32 2 166#define R_ARM_REL32 3 167 168#elif defined(ANDROID_X86_LINKER) 169 170#define R_386_32 1 171#define R_386_PC32 2 172#define R_386_GLOB_DAT 6 173#define R_386_JUMP_SLOT 7 174#define R_386_RELATIVE 8 175 176#elif defined(ANDROID_SH_LINKER) 177 178#define R_SH_DIR32 1 179#define R_SH_GLOB_DAT 163 180#define R_SH_JUMP_SLOT 164 181#define R_SH_RELATIVE 165 182 183#endif /* ANDROID_*_LINKER */ 184 185 186#ifndef DT_INIT_ARRAY 187#define DT_INIT_ARRAY 25 188#endif 189 190#ifndef DT_FINI_ARRAY 191#define DT_FINI_ARRAY 26 192#endif 193 194#ifndef DT_INIT_ARRAYSZ 195#define DT_INIT_ARRAYSZ 27 196#endif 197 198#ifndef DT_FINI_ARRAYSZ 199#define DT_FINI_ARRAYSZ 28 200#endif 201 202#ifndef DT_PREINIT_ARRAY 203#define DT_PREINIT_ARRAY 32 204#endif 205 206#ifndef DT_PREINIT_ARRAYSZ 207#define DT_PREINIT_ARRAYSZ 33 208#endif 209 210soinfo *find_library(const char *name); 211unsigned unload_library(soinfo *si); 212Elf32_Sym *lookup_in_library(soinfo *si, const char *name); 213Elf32_Sym *lookup(const char *name, soinfo **found, soinfo *start); 214soinfo *find_containing_library(void *addr); 215Elf32_Sym *find_containing_symbol(void *addr, soinfo *si); 216const char *linker_get_error(void); 217 218#ifdef ANDROID_ARM_LINKER 219typedef long unsigned int *_Unwind_Ptr; 220_Unwind_Ptr dl_unwind_find_exidx(_Unwind_Ptr pc, int *pcount); 221#elif defined(ANDROID_X86_LINKER) || defined(ANDROID_SH_LINKER) 222int dl_iterate_phdr(int (*cb)(struct dl_phdr_info *, size_t, void *), void *); 223#endif 224 225#endif 226