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-rw-r--r--gnu/usr.bin/gdb/bfd/elf.c248
1 files changed, 248 insertions, 0 deletions
diff --git a/gnu/usr.bin/gdb/bfd/elf.c b/gnu/usr.bin/gdb/bfd/elf.c
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+++ b/gnu/usr.bin/gdb/bfd/elf.c
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+/* ELF executable support for BFD.
+ Copyright 1993 Free Software Foundation, Inc.
+
+This file is part of BFD, the Binary File Descriptor library.
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program 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 General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
+
+/*
+
+SECTION
+ ELF backends
+
+ BFD support for ELF formats is being worked on.
+ Currently, the best supported back ends are for sparc and i386
+ (running svr4 or Solaris 2).
+
+ Documentation of the internals of the support code still needs
+ to be written. The code is changing quickly enough that we
+ haven't bothered yet.
+ */
+
+#include "bfd.h"
+#include "sysdep.h"
+#include "libbfd.h"
+#define ARCH_SIZE 0
+#include "libelf.h"
+
+/* Standard ELF hash function. Do not change this function; you will
+ cause invalid hash tables to be generated. (Well, you would if this
+ were being used yet.) */
+unsigned long
+DEFUN (bfd_elf_hash, (name),
+ CONST unsigned char *name)
+{
+ unsigned long h = 0;
+ unsigned long g;
+ int ch;
+
+ while ((ch = *name++) != '\0')
+ {
+ h = (h << 4) + ch;
+ if ((g = (h & 0xf0000000)) != 0)
+ {
+ h ^= g >> 24;
+ h &= ~g;
+ }
+ }
+ return h;
+}
+
+/* Read a specified number of bytes at a specified offset in an ELF
+ file, into a newly allocated buffer, and return a pointer to the
+ buffer. */
+
+static char *
+DEFUN (elf_read, (abfd, offset, size),
+ bfd * abfd AND
+ long offset AND
+ int size)
+{
+ char *buf;
+
+ if ((buf = bfd_alloc (abfd, size)) == NULL)
+ {
+ bfd_error = no_memory;
+ return NULL;
+ }
+ if (bfd_seek (abfd, offset, SEEK_SET) == -1)
+ {
+ bfd_error = system_call_error;
+ return NULL;
+ }
+ if (bfd_read ((PTR) buf, size, 1, abfd) != size)
+ {
+ bfd_error = system_call_error;
+ return NULL;
+ }
+ return buf;
+}
+
+boolean
+DEFUN (elf_mkobject, (abfd), bfd * abfd)
+{
+ /* this just does initialization */
+ /* coff_mkobject zalloc's space for tdata.coff_obj_data ... */
+ elf_tdata (abfd) = (struct elf_obj_tdata *)
+ bfd_zalloc (abfd, sizeof (struct elf_obj_tdata));
+ if (elf_tdata (abfd) == 0)
+ {
+ bfd_error = no_memory;
+ return false;
+ }
+ /* since everything is done at close time, do we need any
+ initialization? */
+
+ return true;
+}
+
+char *
+DEFUN (elf_get_str_section, (abfd, shindex),
+ bfd * abfd AND
+ unsigned int shindex)
+{
+ Elf_Internal_Shdr **i_shdrp;
+ char *shstrtab = NULL;
+ unsigned int offset;
+ unsigned int shstrtabsize;
+
+ i_shdrp = elf_elfsections (abfd);
+ if (i_shdrp == 0 || i_shdrp[shindex] == 0)
+ return 0;
+
+ shstrtab = i_shdrp[shindex]->rawdata;
+ if (shstrtab == NULL)
+ {
+ /* No cached one, attempt to read, and cache what we read. */
+ offset = i_shdrp[shindex]->sh_offset;
+ shstrtabsize = i_shdrp[shindex]->sh_size;
+ shstrtab = elf_read (abfd, offset, shstrtabsize);
+ i_shdrp[shindex]->rawdata = (void *) shstrtab;
+ }
+ return shstrtab;
+}
+
+char *
+DEFUN (elf_string_from_elf_section, (abfd, shindex, strindex),
+ bfd * abfd AND
+ unsigned int shindex AND
+ unsigned int strindex)
+{
+ Elf_Internal_Shdr *hdr;
+
+ if (strindex == 0)
+ return "";
+
+ hdr = elf_elfsections (abfd)[shindex];
+
+ if (!hdr->rawdata
+ && elf_get_str_section (abfd, shindex) == NULL)
+ return NULL;
+
+ return ((char *) hdr->rawdata) + strindex;
+}
+
+/*
+INTERNAL_FUNCTION
+ bfd_elf_find_section
+
+SYNOPSIS
+ struct elf_internal_shdr *bfd_elf_find_section (bfd *abfd, char *name);
+
+DESCRIPTION
+ Helper functions for GDB to locate the string tables.
+ Since BFD hides string tables from callers, GDB needs to use an
+ internal hook to find them. Sun's .stabstr, in particular,
+ isn't even pointed to by the .stab section, so ordinary
+ mechanisms wouldn't work to find it, even if we had some.
+*/
+
+struct elf_internal_shdr *
+DEFUN (bfd_elf_find_section, (abfd, name),
+ bfd * abfd AND
+ char *name)
+{
+ Elf_Internal_Shdr **i_shdrp;
+ char *shstrtab;
+ unsigned int max;
+ unsigned int i;
+
+ i_shdrp = elf_elfsections (abfd);
+ if (i_shdrp != NULL)
+ {
+ shstrtab = elf_get_str_section (abfd, elf_elfheader (abfd)->e_shstrndx);
+ if (shstrtab != NULL)
+ {
+ max = elf_elfheader (abfd)->e_shnum;
+ for (i = 1; i < max; i++)
+ if (!strcmp (&shstrtab[i_shdrp[i]->sh_name], name))
+ return i_shdrp[i];
+ }
+ }
+ return 0;
+}
+
+const struct bfd_elf_arch_map bfd_elf_arch_map[] = {
+ { bfd_arch_sparc, EM_SPARC },
+ { bfd_arch_i386, EM_386 },
+ { bfd_arch_m68k, EM_68K },
+ { bfd_arch_m88k, EM_88K },
+ { bfd_arch_i860, EM_860 },
+ { bfd_arch_mips, EM_MIPS },
+ { bfd_arch_hppa, EM_HPPA },
+};
+
+const int bfd_elf_arch_map_size = sizeof (bfd_elf_arch_map) / sizeof (bfd_elf_arch_map[0]);
+
+const char *const bfd_elf_section_type_names[] = {
+ "SHT_NULL", "SHT_PROGBITS", "SHT_SYMTAB", "SHT_STRTAB",
+ "SHT_RELA", "SHT_HASH", "SHT_DYNAMIC", "SHT_NOTE",
+ "SHT_NOBITS", "SHT_REL", "SHT_SHLIB", "SHT_DYNSYM",
+};
+
+/* ELF relocs are against symbols. If we are producing relocateable
+ output, and the reloc is against an external symbol, and nothing
+ has given us any additional addend, the resulting reloc will also
+ be against the same symbol. In such a case, we don't want to
+ change anything about the way the reloc is handled, since it will
+ all be done at final link time. Rather than put special case code
+ into bfd_perform_relocation, all the reloc types use this howto
+ function. It just short circuits the reloc if producing
+ relocateable output against an external symbol. */
+
+bfd_reloc_status_type
+bfd_elf_generic_reloc (abfd,
+ reloc_entry,
+ symbol,
+ data,
+ input_section,
+ output_bfd)
+ bfd *abfd;
+ arelent *reloc_entry;
+ asymbol *symbol;
+ PTR data;
+ asection *input_section;
+ bfd *output_bfd;
+{
+ if (output_bfd != (bfd *) NULL
+ && (symbol->flags & BSF_SECTION_SYM) == 0
+ && reloc_entry->addend == 0)
+ {
+ reloc_entry->address += input_section->output_offset;
+ return bfd_reloc_ok;
+ }
+
+ return bfd_reloc_continue;
+}