dl-support.c 2.0 KB

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  1. /*
  2. * Support for dynamic linking code in static libc.
  3. * Copyright (C) 1996-2002, 2003, 2004, 2005 Free Software Foundation, Inc.
  4. *
  5. * Partially based on GNU C Library (file: libc/elf/dl-support.c)
  6. *
  7. * Copyright (C) 2008 STMicroelectronics Ltd.
  8. * Author: Carmelo Amoroso <carmelo.amoroso@st.com>
  9. *
  10. * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
  11. *
  12. */
  13. #include <link.h>
  14. #include <elf.h>
  15. #if defined(USE_TLS) && USE_TLS
  16. #include <assert.h>
  17. #include <tls.h>
  18. #include <ldsodefs.h>
  19. #include <string.h>
  20. #endif
  21. #if defined(USE_TLS) && USE_TLS
  22. void (*_dl_init_static_tls) (struct link_map *) = &_dl_nothread_init_static_tls;
  23. #endif
  24. ElfW(Phdr) *_dl_phdr;
  25. size_t _dl_phnum;
  26. void internal_function _dl_aux_init (ElfW(auxv_t) *av);
  27. void internal_function _dl_aux_init (ElfW(auxv_t) *av)
  28. {
  29. /* Get the program headers base address from the aux vect */
  30. _dl_phdr = (ElfW(Phdr) *) av[AT_PHDR].a_un.a_val;
  31. /* Get the number of program headers from the aux vect */
  32. _dl_phnum = (size_t) av[AT_PHNUM].a_un.a_val;
  33. }
  34. #if defined(USE_TLS) && USE_TLS
  35. /* Initialize static TLS area and DTV for current (only) thread.
  36. libpthread implementations should provide their own hook
  37. to handle all threads. */
  38. void
  39. attribute_hidden
  40. _dl_nothread_init_static_tls (struct link_map *map)
  41. {
  42. # if defined(TLS_TCB_AT_TP)
  43. void *dest = (char *) THREAD_SELF - map->l_tls_offset;
  44. # elif defined(TLS_DTV_AT_TP)
  45. void *dest = (char *) THREAD_SELF + map->l_tls_offset + TLS_PRE_TCB_SIZE;
  46. # else
  47. # error "Either TLS_TCB_AT_TP or TLS_DTV_AT_TP must be defined"
  48. # endif
  49. /* Fill in the DTV slot so that a later LD/GD access will find it. */
  50. dtv_t *dtv = THREAD_DTV ();
  51. assert (map->l_tls_modid <= dtv[-1].counter);
  52. dtv[map->l_tls_modid].pointer.val = dest;
  53. dtv[map->l_tls_modid].pointer.is_static = true;
  54. /* Initialize the memory. */
  55. memset (mempcpy (dest, map->l_tls_initimage, map->l_tls_initimage_size),
  56. '\0', map->l_tls_blocksize - map->l_tls_initimage_size);
  57. }
  58. #endif