102 lines
		
	
	
		
			3.4 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			102 lines
		
	
	
		
			3.4 KiB
		
	
	
	
		
			C
		
	
	
	
| /* Locate the shared object symbol nearest a given address.
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|    Copyright (C) 1996-2000, 2001 Free Software Foundation, Inc.
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|    This file is part of the GNU C Library.
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| 
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|    The GNU C Library is free software; you can redistribute it and/or
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|    modify it under the terms of the GNU Lesser General Public
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|    License as published by the Free Software Foundation; either
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|    version 2.1 of the License, or (at your option) any later version.
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| 
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|    The GNU C Library is distributed in the hope that it will be useful,
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|    but WITHOUT ANY WARRANTY; without even the implied warranty of
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|    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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|    Lesser General Public License for more details.
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| 
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|    You should have received a copy of the GNU Lesser General Public
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|    License along with the GNU C Library; if not, write to the Free
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|    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
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|    02111-1307 USA.  */
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| 
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| #include <dlfcn.h>
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| #include <stddef.h>
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| #include <ldsodefs.h>
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| 
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| int
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| internal_function
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| _dl_addr (const void *address, Dl_info *info)
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| {
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|   const ElfW(Addr) addr = DL_LOOKUP_ADDRESS (address);
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|   struct link_map *l, *match;
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|   const ElfW(Sym) *symtab, *matchsym;
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|   const char *strtab;
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|   ElfW(Word) strtabsize;
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| 
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|   /* Find the highest-addressed object that ADDRESS is not below.  */
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|   match = NULL;
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|   for (l = _dl_loaded; l; l = l->l_next)
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|     if (addr >= l->l_map_start && addr < l->l_map_end)
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|       {
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| 	/* We know ADDRESS lies within L if in any shared object.
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| 	   Make sure it isn't past the end of L's segments.  */
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| 	size_t n = l->l_phnum;
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| 	if (n > 0)
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| 	  {
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| 	    do
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| 	      --n;
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| 	    while (l->l_phdr[n].p_type != PT_LOAD);
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| 	    if (addr >= (l->l_addr +
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| 			 l->l_phdr[n].p_vaddr + l->l_phdr[n].p_memsz))
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| 	      /* Off the end of the highest-addressed shared object.  */
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| 	      continue;
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| 	  }
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| 
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| 	match = l;
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| 	break;
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|       }
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| 
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|   if (match == NULL)
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|     return 0;
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| 
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|   /* Now we know what object the address lies in.  */
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|   info->dli_fname = match->l_name;
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|   info->dli_fbase = (void *) match->l_addr;
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| 
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|   /* If this is the main program the information is incomplete.  */
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|   if (__builtin_expect (info->dli_fbase == NULL, 0))
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|     {
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|       info->dli_fname = _dl_argv[0];
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|       info->dli_fbase = (void *) match->l_map_start;
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|     }
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| 
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|   symtab = (const void *) D_PTR (match, l_info[DT_SYMTAB]);
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|   strtab = (const void *) D_PTR (match, l_info[DT_STRTAB]);
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|   strtabsize = match->l_info[DT_STRSZ]->d_un.d_val;
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| 
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|   /* We assume that the string table follows the symbol table, because
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|      there is no way in ELF to know the size of the dynamic symbol table!!  */
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|   for (matchsym = NULL; (void *) symtab < (void *) strtab; ++symtab)
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|     if (addr >= match->l_addr + symtab->st_value
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| 	&& ((symtab->st_size == 0 && addr == match->l_addr + symtab->st_value)
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| 	    || addr < match->l_addr + symtab->st_value + symtab->st_size)
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| 	&& symtab->st_name < strtabsize
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| 	&& (matchsym == NULL || matchsym->st_value < symtab->st_value)
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| 	&& (ELFW(ST_BIND) (symtab->st_info) == STB_GLOBAL
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| 	    || ELFW(ST_BIND) (symtab->st_info) == STB_WEAK))
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|       matchsym = symtab;
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| 
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|   if (matchsym)
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|     {
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|       /* We found a symbol close by.  Fill in its name and exact address.  */
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|       info->dli_sname = strtab + matchsym->st_name;
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|       info->dli_saddr = (void *) (match->l_addr + matchsym->st_value);
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|     }
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|   else
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|     {
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|       /* No symbol matches.  We return only the containing object.  */
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|       info->dli_sname = NULL;
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|       info->dli_saddr = NULL;
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|     }
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| 
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|   return 1;
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| }
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