1 /* Copyright (C) 1998-2022 Free Software Foundation, Inc.
2    This file is part of the GNU C Library.
3 
4    The GNU C Library is free software; you can redistribute it and/or
5    modify it under the terms of the GNU Lesser General Public
6    License as published by the Free Software Foundation; either
7    version 2.1 of the License, or (at your option) any later version.
8 
9    The GNU C Library is distributed in the hope that it will be useful,
10    but WITHOUT ANY WARRANTY; without even the implied warranty of
11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12    Lesser General Public License for more details.
13 
14    You should have received a copy of the GNU Lesser General Public
15    License along with the GNU C Library; if not, see
16    <https://www.gnu.org/licenses/>.  */
17 
18 #include <stdlib.h>
19 #include <unistd.h>
20 #include <ldsodefs.h>
21 #include <sysdep.h>
22 
23 #ifndef SHARED
24 #include <hwcapinfo.h>
25 #endif
26 #if ENABLE_STATIC_PIE && !defined SHARED
27 /* For elf_machine_load_address.  */
28 #include <dl-machine.h>
29 #endif
30 
31 /* The main work is done in the generic function.  */
32 #define LIBC_START_MAIN generic_start_main
33 #define LIBC_START_DISABLE_INLINE
34 #define LIBC_START_MAIN_AUXVEC_ARG
35 #define MAIN_AUXVEC_ARG
36 #define INIT_MAIN_ARGS
37 #include <csu/libc-start.c>
38 
39 struct startup_info
40   {
41     void *sda_base;
42     int (*main) (int, char **, char **, void *);
43     int (*init) (int, char **, char **, void *);
44     void (*fini) (void);
45   };
46 
47 int
__libc_start_main_impl(int argc,char ** argv,char ** ev,ElfW (auxv_t)* auxvec,void (* rtld_fini)(void),struct startup_info * stinfo,char ** stack_on_entry)48 __libc_start_main_impl (int argc, char **argv,
49 			char **ev,
50 			ElfW (auxv_t) * auxvec,
51 			void (*rtld_fini) (void),
52 			struct startup_info *stinfo,
53 			char **stack_on_entry)
54 {
55   /* the PPC SVR4 ABI says that the top thing on the stack will
56      be a NULL pointer, so if not we assume that we're being called
57      as a statically-linked program by Linux...  */
58   if (*stack_on_entry != NULL)
59     {
60       char **temp;
61       /* ...in which case, we have argc as the top thing on the
62          stack, followed by argv (NULL-terminated), envp (likewise),
63          and the auxiliary vector.  */
64       /* 32/64-bit agnostic load from stack */
65       argc = *(long int *) stack_on_entry;
66       argv = stack_on_entry + 1;
67       ev = argv + argc + 1;
68 #ifdef HAVE_AUX_VECTOR
69       temp = ev;
70       while (*temp != NULL)
71 	++temp;
72       auxvec = (ElfW (auxv_t) *)++ temp;
73 #endif
74       rtld_fini = NULL;
75     }
76 
77   for (ElfW (auxv_t) * av = auxvec; av->a_type != AT_NULL; ++av)
78     switch (av->a_type)
79       {
80       /* For the static case, we also need _dl_hwcap, _dl_hwcap2 and
81          _dl_platform, so we can call
82          __tcb_parse_hwcap_and_convert_at_platform ().  */
83 #ifndef SHARED
84       case AT_HWCAP:
85 	_dl_hwcap = (unsigned long int) av->a_un.a_val;
86 	break;
87       case AT_HWCAP2:
88 	_dl_hwcap2 = (unsigned long int) av->a_un.a_val;
89 	break;
90       case AT_PLATFORM:
91 	_dl_platform = (void *) av->a_un.a_val;
92 	break;
93 #endif
94       }
95 
96   /* Initialize hwcap/hwcap2 and platform data so it can be copied to
97      the TCB later in __libc_setup_tls (). (static case only).  */
98 #ifndef SHARED
99   __tcb_parse_hwcap_and_convert_at_platform ();
100 #endif
101 
102   void *stmain = stinfo->main;
103 #if ENABLE_STATIC_PIE && !defined SHARED
104   struct link_map *map = _dl_get_dl_main_map ();
105   if (!map->l_relocated)
106     stmain = (char *) stmain + elf_machine_load_address ();
107 #endif
108 
109   return generic_start_main (stmain, argc, argv, auxvec,
110 			     NULL, NULL, rtld_fini,
111 			     stack_on_entry);
112 }
113 DEFINE_LIBC_START_MAIN_VERSION
114