Branch data     Line data    Source code

       1                 :            : /* Find debugging and symbol information for a module in libdwfl.
       2                 :            :    Copyright (C) 2006-2010 Red Hat, Inc.
       3                 :            :    This file is part of elfutils.
       4                 :            : 
       5                 :            :    This file is free software; you can redistribute it and/or modify
       6                 :            :    it under the terms of either
       7                 :            : 
       8                 :            :      * the GNU Lesser General Public License as published by the Free
       9                 :            :        Software Foundation; either version 3 of the License, or (at
      10                 :            :        your option) any later version
      11                 :            : 
      12                 :            :    or
      13                 :            : 
      14                 :            :      * the GNU General Public License as published by the Free
      15                 :            :        Software Foundation; either version 2 of the License, or (at
      16                 :            :        your option) any later version
      17                 :            : 
      18                 :            :    or both in parallel, as here.
      19                 :            : 
      20                 :            :    elfutils is distributed in the hope that it will be useful, but
      21                 :            :    WITHOUT ANY WARRANTY; without even the implied warranty of
      22                 :            :    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      23                 :            :    General Public License for more details.
      24                 :            : 
      25                 :            :    You should have received copies of the GNU General Public License and
      26                 :            :    the GNU Lesser General Public License along with this program.  If
      27                 :            :    not, see <http://www.gnu.org/licenses/>.  */
      28                 :            : 
      29                 :            : #include "libdwflP.h"
      30                 :            : 
      31                 :            : const char *
      32                 :  458052789 : dwfl_module_getsym (Dwfl_Module *mod, int ndx,
      33                 :            :                     GElf_Sym *sym, GElf_Word *shndxp)
      34                 :            : {
      35         [ +  - ]:  458052789 :   if (unlikely (mod == NULL))
      36                 :            :     return NULL;
      37                 :            : 
      38         [ -  + ]:  458052789 :   if (unlikely (mod->symdata == NULL))
      39                 :            :     {
      40                 :          0 :       int result = INTUSE(dwfl_module_getsymtab) (mod);
      41         [ #  # ]:          0 :       if (result < 0)
      42                 :            :         return NULL;
      43                 :            :     }
      44                 :            : 
      45                 :            :   GElf_Word shndx;
      46                 :  458052789 :   sym = gelf_getsymshndx (mod->symdata, mod->symxndxdata, ndx, sym, &shndx);
      47         [ -  + ]:  458052789 :   if (unlikely (sym == NULL))
      48                 :            :     {
      49                 :          0 :       __libdwfl_seterrno (DWFL_E_LIBELF);
      50                 :            :       return NULL;
      51                 :            :     }
      52                 :            : 
      53         [ +  - ]:  458052789 :   if (sym->st_shndx != SHN_XINDEX)
      54                 :  458052789 :     shndx = sym->st_shndx;
      55                 :            : 
      56                 :            :   /* Figure out whether this symbol points into an SHF_ALLOC section.  */
      57                 :  458052789 :   bool alloc = true;
      58 [ -  + ][ #  # ]:  458052789 :   if ((shndxp != NULL || mod->e_type != ET_REL)
      59         [ +  + ]:  458052789 :       && (sym->st_shndx == SHN_XINDEX
      60                 :  458052789 :           || (sym->st_shndx < SHN_LORESERVE && sym->st_shndx != SHN_UNDEF)))
      61                 :            :     {
      62                 :            :       GElf_Shdr shdr_mem;
      63                 :  375161914 :       GElf_Shdr *shdr = gelf_getshdr (elf_getscn (mod->symfile->elf, shndx),
      64                 :            :                                       &shdr_mem);
      65 [ +  + ][ +  + ]:  375161914 :       alloc = unlikely (shdr == NULL) || (shdr->sh_flags & SHF_ALLOC);
      66                 :            :     }
      67                 :            : 
      68         [ +  - ]:  458052789 :   if (shndxp != NULL)
      69                 :            :     /* Yield -1 in case of a non-SHF_ALLOC section.  */
      70         [ +  + ]:  458052789 :     *shndxp = alloc ? shndx : (GElf_Word) -1;
      71                 :            : 
      72         [ +  + ]:  458052789 :   switch (sym->st_shndx)
      73                 :            :     {
      74                 :            :     case SHN_ABS:               /* XXX sometimes should use bias?? */
      75                 :            :     case SHN_UNDEF:
      76                 :            :     case SHN_COMMON:
      77                 :            :       break;
      78                 :            : 
      79                 :            :     default:
      80         [ +  + ]:  375161914 :       if (mod->e_type == ET_REL)
      81                 :            :         {
      82                 :            :           /* In an ET_REL file, the symbol table values are relative
      83                 :            :              to the section, not to the module's load base.  */
      84                 :     828626 :           size_t symshstrndx = SHN_UNDEF;
      85                 :     828626 :           Dwfl_Error result = __libdwfl_relocate_value (mod, mod->symfile->elf,
      86                 :            :                                                         &symshstrndx,
      87                 :     828626 :                                                         shndx, &sym->st_value);
      88         [ -  + ]:     828626 :           if (unlikely (result != DWFL_E_NOERROR))
      89                 :            :             {
      90                 :     828626 :               __libdwfl_seterrno (result);
      91                 :            :               return NULL;
      92                 :            :             }
      93                 :            :         }
      94         [ +  + ]:  374333288 :       else if (alloc)
      95                 :            :         /* Apply the bias to the symbol value.  */
      96                 :  371753045 :         sym->st_value = dwfl_adjusted_st_value (mod, sym->st_value);
      97                 :            :       break;
      98                 :            :     }
      99                 :            : 
     100         [ -  + ]:  458052789 :   if (unlikely (sym->st_name >= mod->symstrdata->d_size))
     101                 :            :     {
     102                 :          0 :       __libdwfl_seterrno (DWFL_E_BADSTROFF);
     103                 :            :       return NULL;
     104                 :            :     }
     105                 :  458052789 :   return (const char *) mod->symstrdata->d_buf + sym->st_name;
     106                 :            : }
     107                 :  371753045 : INTDEF (dwfl_module_getsym)