1/* libunwind - a platform-independent unwind library
2   Copyright (C) 2003, 2005 Hewlett-Packard Co
3   Copyright (C) 2007 David Mosberger-Tang
4	Contributed by David Mosberger-Tang <dmosberger@gmail.com>
5
6This file is part of libunwind.
7
8Permission is hereby granted, free of charge, to any person obtaining
9a copy of this software and associated documentation files (the
10"Software"), to deal in the Software without restriction, including
11without limitation the rights to use, copy, modify, merge, publish,
12distribute, sublicense, and/or sell copies of the Software, and to
13permit persons to whom the Software is furnished to do so, subject to
14the following conditions:
15
16The above copyright notice and this permission notice shall be
17included in all copies or substantial portions of the Software.
18
19THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
20EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
21MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
22NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
23LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
24OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
25WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.  */
26
27#include <fcntl.h>
28#include <unistd.h>
29
30#include <sys/mman.h>
31#include <sys/stat.h>
32
33#include "libunwind_i.h"
34#include "map_info.h"
35
36#if ELF_CLASS == ELFCLASS32
37# define ELF_W(x)	ELF32_##x
38# define Elf_W(x)	Elf32_##x
39# define elf_w(x)	_Uelf32_##x
40#else
41# define ELF_W(x)	ELF64_##x
42# define Elf_W(x)	Elf64_##x
43# define elf_w(x)	_Uelf64_##x
44#endif
45
46extern int elf_w (get_proc_name) (unw_addr_space_t as,
47				  pid_t pid, unw_word_t ip,
48				  char *buf, size_t len,
49				  unw_word_t *offp);
50
51extern int elf_w (get_proc_name_in_image) (unw_addr_space_t as,
52					   struct elf_image *ei,
53					   unsigned long segbase,
54					   unsigned long mapoff,
55					   unw_word_t ip,
56					   char *buf, size_t buf_len, unw_word_t *offp);
57
58static inline int
59elf_w (valid_object) (struct elf_image *ei)
60{
61  if (ei->size <= EI_VERSION)
62    return 0;
63
64  return (memcmp (ei->image, ELFMAG, SELFMAG) == 0
65	  && ((uint8_t *) ei->image)[EI_CLASS] == ELF_CLASS
66	  && ((uint8_t *) ei->image)[EI_VERSION] != EV_NONE
67	  && ((uint8_t *) ei->image)[EI_VERSION] <= EV_CURRENT);
68}
69
70static inline int
71elf_map_image (struct elf_image *ei, const char *path)
72{
73  struct stat stat;
74  int fd;
75
76  fd = open (path, O_RDONLY);
77  if (fd < 0)
78    return -1;
79
80  if (fstat (fd, &stat) < 0)
81    {
82      close (fd);
83      return -1;
84    }
85
86  ei->size = stat.st_size;
87  ei->image = mmap (NULL, ei->size, PROT_READ, MAP_PRIVATE, fd, 0);
88  close (fd);
89  if (ei->image == MAP_FAILED)
90    return -1;
91
92  if (!elf_w (valid_object) (ei))
93  {
94    munmap(ei->image, ei->size);
95    return -1;
96  }
97
98  return 0;
99}
100
101/* ANDROID support update */
102static inline int
103elf_map_cached_image (struct map_info *map, unw_word_t ip)
104{
105  intrmask_t saved_mask;
106  int return_value = 0;
107
108  /* Lock while loading the cached elf image. */
109  lock_acquire (&map->ei_lock, saved_mask);
110  if (map->ei.image == NULL)
111    {
112      if (elf_map_image(&map->ei, map->path) < 0)
113        {
114          map->ei.image = NULL;
115          return_value = -1;
116        }
117    }
118  lock_release (&map->ei_lock, saved_mask);
119  return return_value;
120}
121/* End of ANDROID update */
122