sysdeps/unix/sysv/linux/powerpc/libc-start.c

   1 /* Copyright (C) 1998-2024 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
  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_HWCAP3:
  91         _dl_hwcap3 = (unsigned long int) av->a_un.a_val;
  92         break;
  93       case AT_HWCAP4:
  94         _dl_hwcap4 = (unsigned long int) av->a_un.a_val;
  95         break;
  96       case AT_PLATFORM:
  97         _dl_platform = (void *) av->a_un.a_val;
  98         break;
  99 #endif
 100       }
 101
 102   /* Initialize hwcap/hwcap2 and platform data so it can be copied to
 103      the TCB later in __libc_setup_tls (). (static case only).  */
 104 #ifndef SHARED
 105   __tcb_parse_hwcap_and_convert_at_platform ();
 106 #endif
 107
 108   void *stmain = stinfo->main;
 109 #if ENABLE_STATIC_PIE && !defined SHARED
 110   struct link_map *map = _dl_get_dl_main_map ();
 111   if (!map->l_relocated)
 112     stmain = (char *) stmain + elf_machine_load_address ();
 113 #endif
 114
 115   return generic_start_main (stmain, argc, argv, auxvec,
 116                              NULL, NULL, rtld_fini,
 117                              stack_on_entry);
 118 }
 119 DEFINE_LIBC_START_MAIN_VERSION