1 /*- 2 * Copyright 1996-1998 John D. Polstra. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26 #ifndef __GNUC__ 27 #error "GCC is needed to compile this file" 28 #endif 29 30 #include <sys/cdefs.h> 31 #include <machine/tls.h> 32 #include <elf.h> 33 #include <stdlib.h> 34 35 #include "libc_private.h" 36 #include "initfini.c" 37 #include "crtbrand.c" 38 39 typedef void (*fptr)(void); 40 41 #ifdef GCRT 42 extern void _mcleanup(void); 43 extern void monstartup(void *, void *); 44 extern int eprol; 45 extern int etext; 46 #endif 47 48 /* static ifunc reloc support */ 49 extern const Elf_Rela __rela_iplt_start[] __dso_hidden __weak_symbol; 50 extern const Elf_Rela __rela_iplt_end[] __dso_hidden __weak_symbol; 51 static void fix_iplta(void) __noinline; 52 53 static void 54 fix_iplta(void) 55 { 56 const Elf_Rela *rela, *relalim; 57 Elf_Addr *where, target, *ptr; 58 59 rela = __rela_iplt_start; 60 relalim = __rela_iplt_end; 61 for (; rela < relalim; ++rela) { 62 if (ELF_R_TYPE(rela->r_info) != R_X86_64_IRELATIVE) 63 abort(); 64 ptr = (Elf_Addr *)rela->r_addend; 65 where = (Elf_Addr *)rela->r_offset; 66 target = ((Elf_Addr (*)(void))ptr)(); 67 *where = target; 68 } 69 } 70 71 void _start(char **, void (*)(void)); 72 73 /* The entry function. */ 74 void 75 _start(char **ap, void (*cleanup)(void)) 76 { 77 int argc; 78 char **argv; 79 char **env; 80 81 argc = *(long *)(void *)ap; 82 argv = ap + 1; 83 env = ap + 2 + argc; 84 handle_argv(argc, argv, env); 85 86 /* 87 * Setup the initial TLS space. The RTLD does not set up our TLS 88 * (it can't, it doesn't know how our errno is declared). It simply 89 * does all the groundwork required so that we can call 90 * _rtld_allocate_tls(). 91 */ 92 _init_tls(); 93 _rtld_call_init(); 94 95 if (&_DYNAMIC != NULL) 96 atexit(cleanup); 97 else 98 fix_iplta(); 99 100 #ifdef GCRT 101 atexit(_mcleanup); 102 monstartup(&eprol, &etext); 103 #endif 104 105 handle_static_init(argc, argv, env); 106 #ifdef GCRT 107 /* 108 * This label was previously located just after the monstartup 109 * function. It was relocated after the handle_static_init function 110 * to avoid an alternative conditional optimization performed by 111 * clang. The optimization cause the compilation to fail with a 112 * label redefinition error. The impact of the label relocation is 113 * the loss of profiling of handle_static_init function. 114 */ 115 __asm__("eprol:"); 116 #endif 117 exit(main(argc, argv, env)); 118 } 119