src/elfxx.h

/* libunwind - a platform-independent unwind library
   Copyright (C) 2003, 2005 Hewlett-Packard Co
   Copyright (C) 2007 David Mosberger-Tang
	Contributed by David Mosberger-Tang <dmosberger@gmail.com>

This file is part of libunwind.

Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to
the following conditions:

The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.  */

#include <fcntl.h>
#include <unistd.h>

#include <sys/mman.h>
#include <sys/stat.h>

#include "libunwind_i.h"
#include "map_info.h"

#if ELF_CLASS == ELFCLASS32
# define ELF_W(x)	ELF32_##x
# define Elf_W(x)	Elf32_##x
# define elf_w(x)	_Uelf32_##x
#else
# define ELF_W(x)	ELF64_##x
# define Elf_W(x)	Elf64_##x
# define elf_w(x)	_Uelf64_##x
#endif

extern int elf_w (get_proc_name) (unw_addr_space_t as,
				  pid_t pid, unw_word_t ip,
				  char *buf, size_t len,
				  unw_word_t *offp);

extern int elf_w (get_proc_name_in_image) (unw_addr_space_t as,
					   struct elf_image *ei,
					   unsigned long segbase,
					   unsigned long mapoff,
					   unw_word_t ip,
					   char *buf, size_t buf_len, unw_word_t *offp);

static inline int
elf_w (valid_object) (struct elf_image *ei)
{
  if (ei->size <= EI_VERSION)
    return 0;

  return (memcmp (ei->image, ELFMAG, SELFMAG) == 0
	  && ((uint8_t *) ei->image)[EI_CLASS] == ELF_CLASS
	  && ((uint8_t *) ei->image)[EI_VERSION] != EV_NONE
	  && ((uint8_t *) ei->image)[EI_VERSION] <= EV_CURRENT);
}

static inline int
elf_map_image (struct elf_image *ei, const char *path)
{
  struct stat stat;
  int fd;

  fd = open (path, O_RDONLY);
  if (fd < 0)
    return -1;

  if (fstat (fd, &stat) < 0)
    {
      close (fd);
      return -1;
    }

  ei->size = stat.st_size;
  ei->image = mmap (NULL, ei->size, PROT_READ, MAP_PRIVATE, fd, 0);
  close (fd);
  if (ei->image == MAP_FAILED)
    return -1;

  if (!elf_w (valid_object) (ei))
  {
    munmap(ei->image, ei->size);
    return -1;
  }

  return 0;
}

/* ANDROID support update */
static inline int
elf_map_cached_image (struct map_info *map, unw_word_t ip)
{
  intrmask_t saved_mask;
  int return_value = 0;

  /* Lock while loading the cached elf image. */
  lock_acquire (&map->ei_lock, saved_mask);
  if (map->ei.image == NULL)
    {
      if (elf_map_image(&map->ei, map->path) < 0)
        {
          map->ei.image = NULL;
          return_value = -1;
        }
    }
  lock_release (&map->ei_lock, saved_mask);
  return return_value;
}
/* End of ANDROID update */