1 /* Copyright (C) 1998-2006, 2007 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
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.
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.
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, write to the Free
16 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
26 extern void __libc_init_first (int argc, char **argv, char **envp);
28 extern int __libc_multiple_libcs;
32 # include <dl-osinfo.h>
33 extern void __pthread_initialize_minimal (void);
34 # ifndef THREAD_SET_STACK_GUARD
35 /* Only exported for architectures that don't store the stack guard canary
36 in thread local area. */
37 uintptr_t __stack_chk_guard attribute_relro;
41 #ifdef HAVE_PTR_NTHREADS
42 /* We need atomic operations. */
47 #ifdef LIBC_START_MAIN
48 # ifdef LIBC_START_DISABLE_INLINE
49 # define STATIC static
51 # define STATIC static inline __attribute__ ((always_inline))
55 # define LIBC_START_MAIN BP_SYM (__libc_start_main)
58 #ifdef MAIN_AUXVEC_ARG
59 /* main gets passed a pointer to the auxiliary. */
60 # define MAIN_AUXVEC_DECL , void *
61 # define MAIN_AUXVEC_PARAM , auxvec
63 # define MAIN_AUXVEC_DECL
64 # define MAIN_AUXVEC_PARAM
67 STATIC int LIBC_START_MAIN (int (*main) (int, char **, char **
70 char *__unbounded *__unbounded ubp_av,
71 #ifdef LIBC_START_MAIN_AUXVEC_ARG
72 ElfW(auxv_t) *__unbounded auxvec,
76 void (*rtld_fini) (void),
77 void *__unbounded stack_end)
78 __attribute__ ((noreturn));
81 /* Note: the fini parameter is ignored here for shared library. It
82 is registered with __cxa_atexit. This had the disadvantage that
83 finalizers were called in more than one place. */
85 LIBC_START_MAIN (int (*main) (int, char **, char ** MAIN_AUXVEC_DECL),
86 int argc, char *__unbounded *__unbounded ubp_av,
87 #ifdef LIBC_START_MAIN_AUXVEC_ARG
88 ElfW(auxv_t) *__unbounded auxvec,
92 void (*rtld_fini) (void), void *__unbounded stack_end)
94 #if __BOUNDED_POINTERS__
100 /* Result of the 'main' function. */
103 __libc_multiple_libcs = &_dl_starting_up && !_dl_starting_up;
106 char *__unbounded *__unbounded ubp_ev = &ubp_av[argc + 1];
108 INIT_ARGV_and_ENVIRON;
110 /* Store the lowest stack address. This is done in ld.so if this is
111 the code for the DSO. */
112 __libc_stack_end = stack_end;
114 # ifdef HAVE_AUX_VECTOR
115 /* First process the auxiliary vector since we need to find the
116 program header to locate an eventually present PT_TLS entry. */
117 # ifndef LIBC_START_MAIN_AUXVEC_ARG
118 ElfW(auxv_t) *__unbounded auxvec;
120 char *__unbounded *__unbounded evp = ubp_ev;
121 while (*evp++ != NULL)
123 auxvec = (ElfW(auxv_t) *__unbounded) evp;
126 _dl_aux_init (auxvec);
128 # ifdef DL_SYSDEP_OSCHECK
129 if (!__libc_multiple_libcs)
131 /* This needs to run to initiliaze _dl_osversion before TLS
132 setup might check it. */
133 DL_SYSDEP_OSCHECK (__libc_fatal);
137 /* Initialize the thread library at least a bit since the libgcc
138 functions are using thread functions if these are available and
139 we need to setup errno. */
140 __pthread_initialize_minimal ();
142 /* Set up the stack checker's canary. */
143 uintptr_t stack_chk_guard = _dl_setup_stack_chk_guard ();
144 # ifdef THREAD_SET_STACK_GUARD
145 THREAD_SET_STACK_GUARD (stack_chk_guard);
147 __stack_chk_guard = stack_chk_guard;
155 /* Register the destructor of the dynamic linker if there is any. */
156 if (__builtin_expect (rtld_fini != NULL, 1))
157 __cxa_atexit ((void (*) (void *)) rtld_fini, NULL, NULL);
160 /* Call the initializer of the libc. This is only needed here if we
161 are compiling for the static library in which case we haven't
162 run the constructors in `_dl_start_user'. */
163 __libc_init_first (argc, argv, __environ);
165 /* Register the destructor of the program, if any. */
167 __cxa_atexit ((void (*) (void *)) fini, NULL, NULL);
169 /* Some security at this point. Prevent starting a SUID binary where
170 the standard file descriptors are not opened. We have to do this
171 only for statically linked applications since otherwise the dynamic
172 loader did the work already. */
173 if (__builtin_expect (__libc_enable_secure, 0))
174 __libc_check_standard_fds ();
177 /* Call the initializer of the program, if any. */
179 if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_IMPCALLS, 0))
180 GLRO(dl_debug_printf) ("\ninitialize program: %s\n\n", argv[0]);
183 (*init) (argc, argv, __environ MAIN_AUXVEC_PARAM);
186 /* Auditing checkpoint: we have a new object. */
187 if (__builtin_expect (GLRO(dl_naudit) > 0, 0))
189 struct audit_ifaces *afct = GLRO(dl_audit);
190 struct link_map *head = GL(dl_ns)[LM_ID_BASE]._ns_loaded;
191 for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt)
193 if (afct->preinit != NULL)
194 afct->preinit (&head->l_audit[cnt].cookie);
202 if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_IMPCALLS, 0))
203 GLRO(dl_debug_printf) ("\ntransferring control: %s\n\n", argv[0]);
206 #ifdef HAVE_CLEANUP_JMP_BUF
207 /* Memory for the cancellation buffer. */
208 struct pthread_unwind_buf unwind_buf;
211 not_first_call = setjmp ((struct __jmp_buf_tag *) unwind_buf.cancel_jmp_buf);
212 if (__builtin_expect (! not_first_call, 1))
214 struct pthread *self = THREAD_SELF;
216 /* Store old info. */
217 unwind_buf.priv.data.prev = THREAD_GETMEM (self, cleanup_jmp_buf);
218 unwind_buf.priv.data.cleanup = THREAD_GETMEM (self, cleanup);
220 /* Store the new cleanup handler info. */
221 THREAD_SETMEM (self, cleanup_jmp_buf, &unwind_buf);
223 /* Run the program. */
224 result = main (argc, argv, __environ MAIN_AUXVEC_PARAM);
228 /* Remove the thread-local data. */
230 PTHFCT_CALL (ptr__nptl_deallocate_tsd, ());
232 extern void __nptl_deallocate_tsd (void) __attribute ((weak));
233 __nptl_deallocate_tsd ();
236 /* One less thread. Decrement the counter. If it is zero we
237 terminate the entire process. */
240 unsigned int *ptr = __libc_pthread_functions.ptr_nthreads;
243 extern unsigned int __nptl_nthreads __attribute ((weak));
244 unsigned int *const ptr = &__nptl_nthreads;
247 if (! atomic_decrement_and_test (ptr))
248 /* Not much left to do but to exit the thread, not the process. */
252 /* Nothing fancy, just call the function. */
253 result = main (argc, argv, __environ MAIN_AUXVEC_PARAM);