Update.
[glibc.git] / elf / do-rel.h
blobbad102549bef3906cc7e1bb7b5f9f56d163220e0
1 /* Do relocations for ELF dynamic linking.
2 Copyright (C) 1995,96,97,98,99,2000,2001,2002 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, write to the Free
17 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
18 02111-1307 USA. */
20 /* This file may be included twice, to define both
21 `elf_dynamic_do_rel' and `elf_dynamic_do_rela'. */
23 #ifdef DO_RELA
24 # define elf_dynamic_do_rel elf_dynamic_do_rela
25 # define RELCOUNT_IDX VERSYMIDX (DT_RELACOUNT)
26 # define Rel Rela
27 # define elf_machine_rel elf_machine_rela
28 # define elf_machine_rel_relative elf_machine_rela_relative
29 #else
30 # define RELCOUNT_IDX VERSYMIDX (DT_RELCOUNT)
31 #endif
33 #ifndef VERSYMIDX
34 # define VERSYMIDX(sym) (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGIDX (sym))
35 #endif
36 #ifndef VALIDX
37 # define VALIDX(tag) (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGNUM \
38 + DT_EXTRANUM + DT_VALTAGIDX (tag))
39 #endif
41 /* Perform the relocations in MAP on the running program image as specified
42 by RELTAG, SZTAG. If LAZY is nonzero, this is the first pass on PLT
43 relocations; they should be set up to call _dl_runtime_resolve, rather
44 than fully resolved now. */
46 static inline void
47 elf_dynamic_do_rel (struct link_map *map,
48 ElfW(Addr) reladdr, ElfW(Addr) relsize,
49 int lazy)
51 const ElfW(Rel) *r = (const void *) reladdr;
52 const ElfW(Rel) *end = (const void *) (reladdr + relsize);
53 ElfW(Addr) l_addr = map->l_addr;
55 #if (!defined DO_RELA || !defined ELF_MACHINE_PLT_REL) && !defined RTLD_BOOTSTRAP
56 /* We never bind lazily during ld.so bootstrap. Unfortunately gcc is
57 not clever enough to see through all the function calls to realize
58 that. */
59 if (lazy)
61 /* Doing lazy PLT relocations; they need very little info. */
62 for (; r < end; ++r)
63 elf_machine_lazy_rel (map, l_addr, r);
65 else
66 #endif
68 const ElfW(Sym) *const symtab =
69 (const void *) D_PTR (map, l_info[DT_SYMTAB]);
70 ElfW(Word) nrelative = (map->l_info[RELCOUNT_IDX] == NULL
71 ? 0 : map->l_info[RELCOUNT_IDX]->d_un.d_val);
72 const ElfW(Rel) *relative = r;
73 r = r + MIN (nrelative, relsize / sizeof (ElfW(Rel)));
75 #ifndef RTLD_BOOTSTRAP
76 /* This is defined in rtld.c, but nowhere in the static libc.a; make
77 the reference weak so static programs can still link. This
78 declaration cannot be done when compiling rtld.c (i.e. #ifdef
79 RTLD_BOOTSTRAP) because rtld.c contains the common defn for
80 _dl_rtld_map, which is incompatible with a weak decl in the same
81 file. */
82 # ifndef SHARED
83 weak_extern (GL(dl_rtld_map));
84 # endif
85 if (map != &GL(dl_rtld_map)) /* Already done in rtld itself. */
86 # if !defined DO_RELA || defined ELF_MACHINE_REL_RELATIVE
87 /* Rela platforms get the offset from r_addend and this must
88 be copied in the relocation address. Therefore we can skip
89 the relative relocations only if this is for rel
90 relocations or rela relocations if they are computed as
91 memory_loc += l_addr... */
92 if (l_addr != 0)
93 # else
94 /* ...or we know the object has been prelinked. */
95 if (l_addr != 0 || ! map->l_info[VALIDX(DT_GNU_PRELINKED)])
96 # endif
97 #endif
98 for (; relative < r; ++relative)
99 elf_machine_rel_relative (l_addr, relative,
100 (void *) (l_addr + relative->r_offset));
102 #ifdef RTLD_BOOTSTRAP
103 /* The dynamic linker always uses versioning. */
104 assert (map->l_info[VERSYMIDX (DT_VERSYM)] != NULL);
105 #else
106 if (map->l_info[VERSYMIDX (DT_VERSYM)])
107 #endif
109 const ElfW(Half) *const version =
110 (const void *) D_PTR (map, l_info[VERSYMIDX (DT_VERSYM)]);
112 for (; r < end; ++r)
114 ElfW(Half) ndx = version[ELFW(R_SYM) (r->r_info)];
115 elf_machine_rel (map, r, &symtab[ELFW(R_SYM) (r->r_info)],
116 &map->l_versions[ndx],
117 (void *) (l_addr + r->r_offset));
120 #ifndef RTLD_BOOTSTRAP
121 else
122 for (; r < end; ++r)
123 elf_machine_rel (map, r, &symtab[ELFW(R_SYM) (r->r_info)], NULL,
124 (void *) (l_addr + r->r_offset));
125 #endif
129 #undef elf_dynamic_do_rel
130 #undef Rel
131 #undef elf_machine_rel
132 #undef elf_machine_rel_relative
133 #undef RELCOUNT_IDX