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
14 #include <link.h>
15 #include <ldso.h>
16 #include <elf.h>
17 #if defined(USE_TLS) && USE_TLS
18 #include <assert.h>
19 #include <tls.h>
20 #include <ldsodefs.h>
21 #include <string.h>
22 #endif
23 #include <bits/uClibc_page.h>
24
25 #if defined(USE_TLS) && USE_TLS
26
27 void (*_dl_init_static_tls) (struct link_map *) = &_dl_nothread_init_static_tls;
28
29 #endif
30
31 ElfW(Phdr) *_dl_phdr;
32 size_t _dl_phnum;
33 size_t _dl_pagesize;
34
35 ElfW(auxv_t) _dl_auxvt[AUX_MAX_AT_ID];
36 ElfW(auxv_t) *_dl_auxv_start;
37
38 void internal_function _dl_aux_init (ElfW(auxv_t) *av);
_dl_aux_init(ElfW (auxv_t)* av)39 void internal_function _dl_aux_init (ElfW(auxv_t) *av)
40 {
41 _dl_auxv_start = av;
42
43 memset(_dl_auxvt, 0x00, sizeof(_dl_auxvt));
44 for (; av->a_type != AT_NULL; av++)
45 {
46 if (av->a_type < AUX_MAX_AT_ID)
47 _dl_auxvt[av->a_type] = *av;
48 }
49
50 /* Get the program headers base address from the aux vect */
51 _dl_phdr = (ElfW(Phdr) *) _dl_auxvt[AT_PHDR].a_un.a_val;
52
53 /* Get the number of program headers from the aux vect */
54 _dl_phnum = (size_t) _dl_auxvt[AT_PHNUM].a_un.a_val;
55
56 /* Get the pagesize from the aux vect */
57 _dl_pagesize = (_dl_auxvt[AT_PAGESZ].a_un.a_val) ? (size_t) _dl_auxvt[AT_PAGESZ].a_un.a_val : PAGE_SIZE;
58 }
59
60 #if defined(USE_TLS) && USE_TLS
61 /* Initialize static TLS area and DTV for current (only) thread.
62 libpthread implementations should provide their own hook
63 to handle all threads. */
64 void
65 attribute_hidden
_dl_nothread_init_static_tls(struct link_map * map)66 _dl_nothread_init_static_tls (struct link_map *map)
67 {
68 # if defined(TLS_TCB_AT_TP)
69 void *dest = (char *) THREAD_SELF - map->l_tls_offset;
70 # elif defined(TLS_DTV_AT_TP)
71 void *dest = (char *) THREAD_SELF + map->l_tls_offset + TLS_PRE_TCB_SIZE;
72 # else
73 # error "Either TLS_TCB_AT_TP or TLS_DTV_AT_TP must be defined"
74 # endif
75
76 /* Fill in the DTV slot so that a later LD/GD access will find it. */
77 dtv_t *dtv = THREAD_DTV ();
78 assert (map->l_tls_modid <= dtv[-1].counter);
79 dtv[map->l_tls_modid].pointer.val = dest;
80 dtv[map->l_tls_modid].pointer.is_static = true;
81
82 /* Initialize the memory. */
83 memset (mempcpy (dest, map->l_tls_initimage, map->l_tls_initimage_size),
84 '\0', map->l_tls_blocksize - map->l_tls_initimage_size);
85 }
86
87 #endif
88
89