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Diffstat (limited to 'csu/libc-start.c')
| -rw-r--r-- | csu/libc-start.c | 263 |
1 files changed, 263 insertions, 0 deletions
diff --git a/csu/libc-start.c b/csu/libc-start.c new file mode 100644 index 0000000..194db6b --- /dev/null +++ b/csu/libc-start.c @@ -0,0 +1,263 @@ +/* Copyright (C) 1998-2003, 2004, 2005 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <stdlib.h> +#include <stdio.h> +#include <unistd.h> +#include <ldsodefs.h> +#include <bp-start.h> +#include <bp-sym.h> + +extern void __libc_init_first (int argc, char **argv, char **envp); + +extern int __libc_multiple_libcs; + +#include <tls.h> +#ifndef SHARED +# include <dl-osinfo.h> +extern void __pthread_initialize_minimal (void) +# if !(USE_TLS - 0) && !defined NONTLS_INIT_TP + __attribute__ ((weak)) +# endif + ; +# ifndef THREAD_SET_STACK_GUARD +/* Only exported for architectures that don't store the stack guard canary + in thread local area. */ +uintptr_t __stack_chk_guard attribute_relro; +# endif +#endif + +#ifdef HAVE_PTR_NTHREADS +/* We need atomic operations. */ +# include <atomic.h> +#endif + + +#ifdef LIBC_START_MAIN +# ifdef LIBC_START_DISABLE_INLINE +# define STATIC static +# else +# define STATIC static inline __attribute__ ((always_inline)) +# endif +#else +# define STATIC +# define LIBC_START_MAIN BP_SYM (__libc_start_main) +#endif + +#ifdef MAIN_AUXVEC_ARG +/* main gets passed a pointer to the auxiliary. */ +# define MAIN_AUXVEC_DECL , void * +# define MAIN_AUXVEC_PARAM , auxvec +#else +# define MAIN_AUXVEC_DECL +# define MAIN_AUXVEC_PARAM +#endif + +STATIC int LIBC_START_MAIN (int (*main) (int, char **, char ** + MAIN_AUXVEC_DECL), + int argc, + char *__unbounded *__unbounded ubp_av, +#ifdef LIBC_START_MAIN_AUXVEC_ARG + ElfW(auxv_t) *__unbounded auxvec, +#endif + __typeof (main) init, + void (*fini) (void), + void (*rtld_fini) (void), + void *__unbounded stack_end) + __attribute__ ((noreturn)); + + +/* Note: the fini parameter is ignored here for shared library. It + is registered with __cxa_atexit. This had the disadvantage that + finalizers were called in more than one place. */ +STATIC int +LIBC_START_MAIN (int (*main) (int, char **, char ** MAIN_AUXVEC_DECL), + int argc, char *__unbounded *__unbounded ubp_av, +#ifdef LIBC_START_MAIN_AUXVEC_ARG + ElfW(auxv_t) *__unbounded auxvec, +#endif + __typeof (main) init, + void (*fini) (void), + void (*rtld_fini) (void), void *__unbounded stack_end) +{ +#if __BOUNDED_POINTERS__ + char **argv; +#else +# define argv ubp_av +#endif + + /* Result of the 'main' function. */ + int result; + + __libc_multiple_libcs = &_dl_starting_up && !_dl_starting_up; + +#ifndef SHARED + char *__unbounded *__unbounded ubp_ev = &ubp_av[argc + 1]; + + INIT_ARGV_and_ENVIRON; + + /* Store the lowest stack address. This is done in ld.so if this is + the code for the DSO. */ + __libc_stack_end = stack_end; + +# ifdef HAVE_AUX_VECTOR + /* First process the auxiliary vector since we need to find the + program header to locate an eventually present PT_TLS entry. */ +# ifndef LIBC_START_MAIN_AUXVEC_ARG + ElfW(auxv_t) *__unbounded auxvec; + { + char *__unbounded *__unbounded evp = ubp_ev; + while (*evp++ != NULL) + ; + auxvec = (ElfW(auxv_t) *__unbounded) evp; + } +# endif + _dl_aux_init (auxvec); +# endif +# ifdef DL_SYSDEP_OSCHECK + if (!__libc_multiple_libcs) + { + /* This needs to run to initiliaze _dl_osversion before TLS + setup might check it. */ + DL_SYSDEP_OSCHECK (__libc_fatal); + } +# endif + + /* Initialize the thread library at least a bit since the libgcc + functions are using thread functions if these are available and + we need to setup errno. If there is no thread library and we + handle TLS the function is defined in the libc to initialized the + TLS handling. */ +# if !(USE_TLS - 0) && !defined NONTLS_INIT_TP + if (__pthread_initialize_minimal) +# endif + __pthread_initialize_minimal (); +#endif + +# ifndef SHARED + /* Set up the stack checker's canary. */ + uintptr_t stack_chk_guard = _dl_setup_stack_chk_guard (); +# ifdef THREAD_SET_STACK_GUARD + THREAD_SET_STACK_GUARD (stack_chk_guard); +# else + __stack_chk_guard = stack_chk_guard; +# endif +#endif + + /* Register the destructor of the dynamic linker if there is any. */ + if (__builtin_expect (rtld_fini != NULL, 1)) + __cxa_atexit ((void (*) (void *)) rtld_fini, NULL, NULL); + +#ifndef SHARED + /* Call the initializer of the libc. This is only needed here if we + are compiling for the static library in which case we haven't + run the constructors in `_dl_start_user'. */ + __libc_init_first (argc, argv, __environ); + + /* Register the destructor of the program, if any. */ + if (fini) + __cxa_atexit ((void (*) (void *)) fini, NULL, NULL); + + /* Some security at this point. Prevent starting a SUID binary where + the standard file descriptors are not opened. We have to do this + only for statically linked applications since otherwise the dynamic + loader did the work already. */ + if (__builtin_expect (__libc_enable_secure, 0)) + __libc_check_standard_fds (); +#endif + + /* Call the initializer of the program, if any. */ +#ifdef SHARED + if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_IMPCALLS, 0)) + GLRO(dl_debug_printf) ("\ninitialize program: %s\n\n", argv[0]); +#endif + if (init) + (*init) (argc, argv, __environ MAIN_AUXVEC_PARAM); + +#ifdef SHARED + /* Auditing checkpoint: we have a new object. */ + if (__builtin_expect (GLRO(dl_naudit) > 0, 0)) + { + struct audit_ifaces *afct = GLRO(dl_audit); + struct link_map *head = GL(dl_ns)[LM_ID_BASE]._ns_loaded; + for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt) + { + if (afct->preinit != NULL) + afct->preinit (&head->l_audit[cnt].cookie); + + afct = afct->next; + } + } +#endif + +#ifdef SHARED + if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_IMPCALLS, 0)) + GLRO(dl_debug_printf) ("\ntransferring control: %s\n\n", argv[0]); +#endif + +#ifdef HAVE_CLEANUP_JMP_BUF + /* Memory for the cancellation buffer. */ + struct pthread_unwind_buf unwind_buf; + + int not_first_call; + not_first_call = setjmp ((struct __jmp_buf_tag *) unwind_buf.cancel_jmp_buf); + if (__builtin_expect (! not_first_call, 1)) + { + struct pthread *self = THREAD_SELF; + + /* Store old info. */ + unwind_buf.priv.data.prev = THREAD_GETMEM (self, cleanup_jmp_buf); + unwind_buf.priv.data.cleanup = THREAD_GETMEM (self, cleanup); + + /* Store the new cleanup handler info. */ + THREAD_SETMEM (self, cleanup_jmp_buf, &unwind_buf); + + /* Run the program. */ + result = main (argc, argv, __environ MAIN_AUXVEC_PARAM); + } + else + { + /* Remove the thread-local data. */ +# ifdef SHARED + __libc_pthread_functions.ptr__nptl_deallocate_tsd (); +# else + extern void __nptl_deallocate_tsd (void) __attribute ((weak)); + __nptl_deallocate_tsd (); +# endif + + /* One less thread. Decrement the counter. If it is zero we + terminate the entire process. */ + result = 0; +# ifdef SHARED + unsigned int *const ptr = __libc_pthread_functions.ptr_nthreads; +# else + extern unsigned int __nptl_nthreads __attribute ((weak)); + unsigned int *const ptr = &__nptl_nthreads; +# endif + + if (! atomic_decrement_and_test (ptr)) + /* Not much left to do but to exit the thread, not the process. */ + __exit_thread (0); + } +#else + /* Nothing fancy, just call the function. */ + result = main (argc, argv, __environ MAIN_AUXVEC_PARAM); +#endif + + exit (result); +} |