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      1 /* Read all of the file associated with the descriptor.
      2    Copyright (C) 1998-2009 Red Hat, Inc.
      3    This file is part of Red Hat elfutils.
      4    Contributed by Ulrich Drepper <drepper (at) redhat.com>, 1998.
      5 
      6    Red Hat elfutils is free software; you can redistribute it and/or modify
      7    it under the terms of the GNU General Public License as published by the
      8    Free Software Foundation; version 2 of the License.
      9 
     10    Red Hat elfutils is distributed in the hope that it will be useful, but
     11    WITHOUT ANY WARRANTY; without even the implied warranty of
     12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     13    General Public License for more details.
     14 
     15    You should have received a copy of the GNU General Public License along
     16    with Red Hat elfutils; if not, write to the Free Software Foundation,
     17    Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA.
     18 
     19    In addition, as a special exception, Red Hat, Inc. gives You the
     20    additional right to link the code of Red Hat elfutils with code licensed
     21    under any Open Source Initiative certified open source license
     22    (http://www.opensource.org/licenses/index.php) which requires the
     23    distribution of source code with any binary distribution and to
     24    distribute linked combinations of the two.  Non-GPL Code permitted under
     25    this exception must only link to the code of Red Hat elfutils through
     26    those well defined interfaces identified in the file named EXCEPTION
     27    found in the source code files (the "Approved Interfaces").  The files
     28    of Non-GPL Code may instantiate templates or use macros or inline
     29    functions from the Approved Interfaces without causing the resulting
     30    work to be covered by the GNU General Public License.  Only Red Hat,
     31    Inc. may make changes or additions to the list of Approved Interfaces.
     32    Red Hat's grant of this exception is conditioned upon your not adding
     33    any new exceptions.  If you wish to add a new Approved Interface or
     34    exception, please contact Red Hat.  You must obey the GNU General Public
     35    License in all respects for all of the Red Hat elfutils code and other
     36    code used in conjunction with Red Hat elfutils except the Non-GPL Code
     37    covered by this exception.  If you modify this file, you may extend this
     38    exception to your version of the file, but you are not obligated to do
     39    so.  If you do not wish to provide this exception without modification,
     40    you must delete this exception statement from your version and license
     41    this file solely under the GPL without exception.
     42 
     43    Red Hat elfutils is an included package of the Open Invention Network.
     44    An included package of the Open Invention Network is a package for which
     45    Open Invention Network licensees cross-license their patents.  No patent
     46    license is granted, either expressly or impliedly, by designation as an
     47    included package.  Should you wish to participate in the Open Invention
     48    Network licensing program, please visit www.openinventionnetwork.com
     49    <http://www.openinventionnetwork.com>.  */
     50 
     51 #ifdef HAVE_CONFIG_H
     52 # include <config.h>
     53 #endif
     54 
     55 #include <errno.h>
     56 #include <unistd.h>
     57 #include <sys/stat.h>
     58 
     59 #include <system.h>
     60 #include "libelfP.h"
     61 #include "common.h"
     62 
     63 
     64 static void
     65 set_address (Elf *elf, size_t offset)
     66 {
     67   if (elf->kind == ELF_K_AR)
     68     {
     69       Elf *child = elf->state.ar.children;
     70 
     71       while (child != NULL)
     72 	{
     73 	  if (child->map_address == NULL)
     74 	    {
     75 	      child->map_address = elf->map_address;
     76 	      child->start_offset -= offset;
     77 	      if (child->kind == ELF_K_AR)
     78 		child->state.ar.offset -= offset;
     79 
     80 	      set_address (child, offset);
     81 	    }
     82 
     83 	  child = child->next;
     84 	}
     85     }
     86 }
     87 
     88 
     89 char *
     90 __libelf_readall (elf)
     91      Elf *elf;
     92 {
     93   /* Get the file.  */
     94   rwlock_wrlock (elf->lock);
     95 
     96   if (elf->map_address == NULL && unlikely (elf->fildes == -1))
     97     {
     98       __libelf_seterrno (ELF_E_INVALID_HANDLE);
     99       rwlock_unlock (elf->lock);
    100       return NULL;
    101     }
    102 
    103   /* If the file is not mmap'ed and not previously loaded, do it now.  */
    104   if (elf->map_address == NULL)
    105     {
    106       char *mem = NULL;
    107 
    108       /* If this is an archive and we have derived descriptors get the
    109 	 locks for all of them.  */
    110       libelf_acquire_all (elf);
    111 
    112       if (elf->maximum_size == ~((size_t) 0))
    113 	{
    114 	  /* We don't yet know how large the file is.   Determine that now.  */
    115 	  struct stat st;
    116 
    117 	  if (fstat (elf->fildes, &st) < 0)
    118 	    goto read_error;
    119 
    120 	  if (sizeof (size_t) >= sizeof (st.st_size)
    121 	      || st.st_size <= ~((size_t) 0))
    122 	    elf->maximum_size = (size_t) st.st_size;
    123 	  else
    124 	    {
    125 	      errno = EOVERFLOW;
    126 	      goto read_error;
    127 	    }
    128 	}
    129 
    130       /* Allocate all the memory we need.  */
    131       mem = (char *) malloc (elf->maximum_size);
    132       if (mem != NULL)
    133 	{
    134 	  /* Read the file content.  */
    135 	  if (unlikely ((size_t) pread_retry (elf->fildes, mem,
    136 					      elf->maximum_size,
    137 					      elf->start_offset)
    138 			!= elf->maximum_size))
    139 	    {
    140 	      /* Something went wrong.  */
    141 	    read_error:
    142 	      __libelf_seterrno (ELF_E_READ_ERROR);
    143 	      free (mem);
    144 	    }
    145 	  else
    146 	    {
    147 	      /* Remember the address.  */
    148 	      elf->map_address = mem;
    149 
    150 	      /* Also remember that we allocated the memory.  */
    151 	      elf->flags |= ELF_F_MALLOCED;
    152 
    153 	      /* Propagate the information down to all children and
    154 		 their children.  */
    155 	      set_address (elf, elf->start_offset);
    156 
    157 	      /* Correct the own offsets.  */
    158 	      if (elf->kind == ELF_K_AR)
    159 		elf->state.ar.offset -= elf->start_offset;
    160 	      elf->start_offset = 0;
    161 	    }
    162 	}
    163       else
    164 	__libelf_seterrno (ELF_E_NOMEM);
    165 
    166       /* Free the locks on the children.  */
    167       libelf_release_all (elf);
    168     }
    169 
    170   rwlock_unlock (elf->lock);
    171 
    172   return (char *) elf->map_address;
    173 }
    174