| /* Return string pointer from string section. |
| Copyright (C) 1998, 1999, 2000, 2001, 2002, 2004, 2008, 2009 Red Hat, Inc. |
| This file is part of elfutils. |
| Contributed by Ulrich Drepper <drepper@redhat.com>, 1998. |
| |
| This file is free software; you can redistribute it and/or modify |
| it under the terms of either |
| |
| * the GNU Lesser General Public License as published by the Free |
| Software Foundation; either version 3 of the License, or (at |
| your option) any later version |
| |
| or |
| |
| * 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 |
| |
| or both in parallel, as here. |
| |
| elfutils 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 copies of the GNU General Public License and |
| the GNU Lesser General Public License along with this program. If |
| not, see <http://www.gnu.org/licenses/>. */ |
| |
| #ifdef HAVE_CONFIG_H |
| # include <config.h> |
| #endif |
| |
| #include <libelf.h> |
| #include <stddef.h> |
| |
| #include "libelfP.h" |
| |
| |
| char * |
| elf_strptr (elf, idx, offset) |
| Elf *elf; |
| size_t idx; |
| size_t offset; |
| { |
| if (elf == NULL) |
| return NULL; |
| |
| if (elf->kind != ELF_K_ELF) |
| { |
| __libelf_seterrno (ELF_E_INVALID_HANDLE); |
| return NULL; |
| } |
| |
| rwlock_rdlock (elf->lock); |
| |
| char *result = NULL; |
| Elf_Scn *strscn; |
| |
| /* Find the section in the list. */ |
| Elf_ScnList *runp = (elf->class == ELFCLASS32 |
| || (offsetof (struct Elf, state.elf32.scns) |
| == offsetof (struct Elf, state.elf64.scns)) |
| ? &elf->state.elf32.scns : &elf->state.elf64.scns); |
| while (1) |
| { |
| if (idx < runp->max) |
| { |
| if (idx < runp->cnt) |
| strscn = &runp->data[idx]; |
| else |
| { |
| __libelf_seterrno (ELF_E_INVALID_INDEX); |
| goto out; |
| } |
| break; |
| } |
| |
| idx -= runp->max; |
| |
| runp = runp->next; |
| if (runp == NULL) |
| { |
| __libelf_seterrno (ELF_E_INVALID_INDEX); |
| goto out; |
| } |
| } |
| |
| if (elf->class == ELFCLASS32) |
| { |
| if (unlikely (strscn->shdr.e32->sh_type != SHT_STRTAB)) |
| { |
| /* This is no string section. */ |
| __libelf_seterrno (ELF_E_INVALID_SECTION); |
| goto out; |
| } |
| |
| if (unlikely (offset >= strscn->shdr.e32->sh_size)) |
| { |
| /* The given offset is too big, it is beyond this section. */ |
| __libelf_seterrno (ELF_E_OFFSET_RANGE); |
| goto out; |
| } |
| } |
| else |
| { |
| if (unlikely (strscn->shdr.e64->sh_type != SHT_STRTAB)) |
| { |
| /* This is no string section. */ |
| __libelf_seterrno (ELF_E_INVALID_SECTION); |
| goto out; |
| } |
| |
| if (unlikely (offset >= strscn->shdr.e64->sh_size)) |
| { |
| /* The given offset is too big, it is beyond this section. */ |
| __libelf_seterrno (ELF_E_OFFSET_RANGE); |
| goto out; |
| } |
| } |
| |
| if (strscn->rawdata_base == NULL && ! strscn->data_read) |
| { |
| rwlock_unlock (elf->lock); |
| rwlock_wrlock (elf->lock); |
| if (strscn->rawdata_base == NULL && ! strscn->data_read |
| /* Read the section data. */ |
| && __libelf_set_rawdata_wrlock (strscn) != 0) |
| goto out; |
| } |
| |
| if (likely (strscn->rawdata_base != NULL)) |
| // XXX Is this correct if a file is read and then new data is added |
| // XXX to the string section? Likely needs to check offset against |
| // XXX size of rawdata_base buffer and then iterate over rest of the |
| // XXX list. |
| result = &strscn->rawdata_base[offset]; |
| else |
| { |
| /* This is a file which is currently created. Use the list of |
| data blocks. */ |
| struct Elf_Data_List *dl = &strscn->data_list; |
| while (dl != NULL) |
| { |
| if (offset >= (size_t) dl->data.d.d_off |
| && offset < dl->data.d.d_off + dl->data.d.d_size) |
| { |
| result = (char *) dl->data.d.d_buf + (offset - dl->data.d.d_off); |
| break; |
| } |
| |
| dl = dl->next; |
| } |
| } |
| |
| out: |
| rwlock_unlock (elf->lock); |
| |
| return result; |
| } |
| INTDEF(elf_strptr) |