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-rw-r--r--elf/dynamic-link.h119
1 files changed, 119 insertions, 0 deletions
diff --git a/elf/dynamic-link.h b/elf/dynamic-link.h
new file mode 100644
index 0000000000..1c3af29d6a
--- /dev/null
+++ b/elf/dynamic-link.h
@@ -0,0 +1,119 @@
+/* Inline functions for dynamic linking.
+Copyright (C) 1995 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 Library General Public License as
+published by the Free Software Foundation; either version 2 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
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB. If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA. */
+
+#include <elf.h>
+
+/* This machine-dependent file defines these inline functions. */
+
+static void elf_machine_rel (Elf32_Addr loadaddr, Elf32_Dyn *info[DT_NUM],
+ const Elf32_Rel *reloc,
+ Elf32_Addr sym_loadaddr, const Elf32_Sym *sym);
+static void elf_machine_rela (Elf32_Addr loadaddr, Elf32_Dyn *info[DT_NUM],
+ const Elf32_Rela *reloc,
+ Elf32_Addr sym_loadaddr, const Elf32_Sym *sym);
+static Elf32_Addr *elf_machine_got (void);
+static Elf32_Addr elf_machine_load_address (void);
+
+#include <dl-machine.h>
+
+
+#include <assert.h>
+
+/* Read the dynamic section at DYN and fill in INFO with indices DT_*. */
+
+static inline void
+elf_get_dynamic_info (Elf32_Dyn *dyn, Elf32_Dyn *info[DT_NUM])
+{
+ unsigned int i;
+
+ for (i = 0; i < DT_NUM; ++i)
+ info[i] = NULL;
+
+ while (dyn->d_tag != DT_NULL)
+ {
+ assert (dyn->d_tag < DT_NUM);
+ info[dyn->d_tag] = dyn++;
+ }
+
+ if (info[DT_RELA])
+ assert (info[DT_RELAENT]->d_un.d_val == sizeof (Elf32_Rela));
+ if (info[DT_REL])
+ assert (info[DT_RELENT]->d_un.d_val == sizeof (Elf32_Rel));
+ if (info[DT_PLTREL])
+ assert (info[DT_PLTREL]->d_un.d_val == DT_REL ||
+ info[DT_PLTREL]->d_un.d_val == DT_RELA);
+}
+
+/* Perform the relocations specified by DYNAMIC on the running program
+ image. If LAZY is nonzero, don't relocate PLT entries. *RESOLVE is
+ called to resolve symbol values; it modifies its argument pointer to
+ point to the defining symbol, and returns the base load address of the
+ defining object. */
+
+static inline void
+elf_dynamic_relocate (Elf32_Dyn *dynamic[DT_NUM], Elf32_Addr loadaddr,
+ int lazy, Elf32_Addr (*resolve) (const Elf32_Sym **))
+{
+ const Elf32_Sym *const symtab
+ = (const Elf32_Sym *) dynamic[DT_SYMTAB]->d_un.d_ptr;
+
+ inline Elf32_Addr symvalue (Elf32_Word info, const Elf32_Sym **definer)
+ {
+ if (ELF32_R_SYM (info) == STN_UNDEF)
+ return 0; /* This value will not be consulted. */
+ *definer = &symtab[ELF32_R_SYM (info)];
+ return (*resolve) (definer);
+ }
+
+ /* Perform Elf32_Rel relocations in the section found by RELTAG, SZTAG. */
+ inline void do_rel (Elf32_Word reltag, Elf32_Word sztag)
+ {
+ const Elf32_Rel *r = (const Elf32_Rel *) dynamic[reltag]->d_un.d_ptr;
+ const Elf32_Rel *end = &r[dynamic[sztag]->d_un.d_val / sizeof *r];
+ while (r < end)
+ {
+ const Elf32_Sym *definer;
+ Elf32_Addr loadbase = symvalue (r->r_info, &definer);
+ elf_machine_rel (loadaddr, dynamic, r, loadbase, definer);
+ ++r;
+ }
+ }
+ /* Perform Elf32_Rela relocations in the section found by RELTAG, SZTAG. */
+ inline void do_rela (Elf32_Word reltag, Elf32_Word sztag)
+ {
+ const Elf32_Rela *r = (const Elf32_Rela *) dynamic[reltag]->d_un.d_ptr;
+ const Elf32_Rela *end = &r[dynamic[sztag]->d_un.d_val / sizeof *r];
+ while (r < end)
+ {
+ const Elf32_Sym *definer;
+ Elf32_Addr loadbase = symvalue (r->r_info, &definer);
+ elf_machine_rela (loadaddr, dynamic, r, loadbase, definer);
+ ++r;
+ }
+ }
+
+ if (dynamic[DT_RELA])
+ do_rela (DT_RELA, DT_RELASZ);
+ if (dynamic[DT_REL])
+ do_rel (DT_REL, DT_RELSZ);
+ if (dynamic[DT_JMPREL] && ! lazy)
+ /* Relocate the PLT right now. */
+ (dynamic[DT_PLTREL]->d_un.d_val == DT_REL ? do_rel : do_rela)
+ (DT_JMPREL, DT_PLTRELSZ);
+}