libdl.c

Axis 221 camera embedded programing interface

		if (dl_brk != NULL) {
			_dl_debug_addr->r_state = RT_ADD;
			(*dl_brk) ();

			_dl_debug_addr->r_state = RT_CONSISTENT;
			(*dl_brk) ();
		}
	}

#if defined (__LIBDL_SHARED__)
	/* Run the ctors and setup the dtors */
	for (i = nlist; i; --i) {
		tpnt = init_fini_list[i-1];
		if (tpnt->init_flag & INIT_FUNCS_CALLED)
			continue;
		tpnt->init_flag |= INIT_FUNCS_CALLED;

		if (tpnt->dynamic_info[DT_INIT]) {
			void (*dl_elf_func) (void);
			dl_elf_func = (void (*)(void)) (tpnt->loadaddr + tpnt->dynamic_info[DT_INIT]);
			if (dl_elf_func && *dl_elf_func != NULL) {
#ifdef __SUPPORT_LD_DEBUG__
				if(_dl_debug)
					fprintf(stderr, "running ctors for library %s at '%x'\n", tpnt->libname, dl_elf_func);
#endif
				(*dl_elf_func) ();
			}
		}
	}
#endif
	_dl_unmap_cache();
	return (void *) dyn_chain;

oops:
	/* Something went wrong.  Clean up and return NULL. */
	_dl_unmap_cache();
	do_dlclose(dyn_chain, 0);
	return NULL;
}

void *dlsym(void *vhandle, const char *name)
{
	struct elf_resolve *tpnt, *tfrom;
	struct dyn_elf *handle;
	ElfW(Addr) from;
	struct dyn_elf *rpnt;
	void *ret;

	handle = (struct dyn_elf *) vhandle;

	/* First of all verify that we have a real handle
	   of some kind.  Return NULL if not a valid handle. */

	if (handle == NULL)
		handle = _dl_symbol_tables;
	else if (handle != RTLD_NEXT && handle != _dl_symbol_tables) {
		for (rpnt = _dl_handles; rpnt; rpnt = rpnt->next_handle)
			if (rpnt == handle)
				break;
		if (!rpnt) {
			_dl_error_number = LD_BAD_HANDLE;
			return NULL;
		}
	} else if (handle == RTLD_NEXT) {
		/*
		 * Try and locate the module we were called from - we
		 * need this so that we know where to start searching
		 * from.  We never pass RTLD_NEXT down into the actual
		 * dynamic loader itself, as it doesn't know
		 * how to properly treat it.
		 */
		from = (ElfW(Addr)) __builtin_return_address(0);

		tfrom = NULL;
		for (rpnt = _dl_symbol_tables; rpnt; rpnt = rpnt->next) {
			tpnt = rpnt->dyn;
			if (tpnt->loadaddr < from
					&& (tfrom == NULL || tfrom->loadaddr < tpnt->loadaddr)) {
				tfrom = tpnt;
				handle = rpnt->next;
			}
		}
	}

	ret = _dl_find_hash((char*)name, handle, NULL, 0);

	/*
	 * Nothing found.
	 */
	if (!ret)
		_dl_error_number = LD_NO_SYMBOL;
	return ret;
}

static int do_dlclose(void *vhandle, int need_fini)
{
	struct dyn_elf *rpnt, *rpnt1;
	struct init_fini_list *runp, *tmp;
	ElfW(Phdr) *ppnt;
	struct elf_resolve *tpnt;
	int (*dl_elf_fini) (void);
	void (*dl_brk) (void);
	struct dyn_elf *handle;
	unsigned int end;
	int i = 0;

	handle = (struct dyn_elf *) vhandle;
	rpnt1 = NULL;
	for (rpnt = _dl_handles; rpnt; rpnt = rpnt->next_handle) {
		if (rpnt == handle)
			break;
		rpnt1 = rpnt;
	}

	if (!rpnt) {
		_dl_error_number = LD_BAD_HANDLE;
		return 1;
	}
	if (rpnt1)
		rpnt1->next_handle = rpnt->next_handle;
	else
		_dl_handles = rpnt->next_handle;
	if (need_fini) {
		for (i = 0; i < handle->init_fini.nlist; ++i) {
			tpnt = handle->init_fini.init_fini[i];
			if (tpnt->dynamic_info[DT_FINI] && tpnt->usage_count == 1 &&
			    !(tpnt->init_flag & FINI_FUNCS_CALLED)) {
				tpnt->init_flag |= FINI_FUNCS_CALLED;
				dl_elf_fini = (int (*)(void)) (tpnt->loadaddr + tpnt->dynamic_info[DT_FINI]);
#ifdef __SUPPORT_LD_DEBUG__
				if(_dl_debug)
					fprintf(stderr, "running dtors for library %s at '%x'\n", tpnt->libname, dl_elf_fini);
#endif
				(*dl_elf_fini) ();
			}
		}
	}
	if (handle->dyn->usage_count == 1)
		free(handle->init_fini.init_fini);
	/* OK, this is a valid handle - now close out the file */
	for (rpnt = handle; rpnt; rpnt = rpnt->next) {
		tpnt = rpnt->dyn;
		if (--tpnt->usage_count == 0) {
			end = 0;
			for (i = 0, ppnt = tpnt->ppnt;
					i < tpnt->n_phent; ppnt++, i++) {
				if (ppnt->p_type != PT_LOAD)
					continue;
				if (end < ppnt->p_vaddr + ppnt->p_memsz)
					end = ppnt->p_vaddr + ppnt->p_memsz;
			}
			_dl_munmap((void*)tpnt->loadaddr, end);
			/* Free elements in RTLD_LOCAL scope list */ 
			for (runp = tpnt->rtld_local; runp; runp = tmp) {
				tmp = runp->next;
				free(runp);
			}
			/* Next, remove tpnt from the loaded_module list */
			if (_dl_loaded_modules == tpnt) {
				_dl_loaded_modules = tpnt->next;
				if (_dl_loaded_modules)
					_dl_loaded_modules->prev = 0;
			} else
				for (tpnt = _dl_loaded_modules; tpnt; tpnt = tpnt->next)
					if (tpnt->next == rpnt->dyn) {
						tpnt->next = tpnt->next->next;
						if (tpnt->next)
							tpnt->next->prev = tpnt;
						break;
					}

			/* Next, remove tpnt from the global symbol table list */
			if (_dl_symbol_tables->dyn == rpnt->dyn) {
				_dl_symbol_tables = rpnt->next;
				if (_dl_symbol_tables)
					_dl_symbol_tables->prev = 0;
			} else
				for (rpnt1 = _dl_symbol_tables; rpnt1->next; rpnt1 = rpnt1->next) {
					if (rpnt1->next->dyn == rpnt->dyn) {
						free(rpnt1->next);
						rpnt1->next = rpnt1->next->next;
						if (rpnt1->next)
							rpnt1->next->prev = rpnt1;
						break;
					}
				}
			free(rpnt->dyn->libname);
			free(rpnt->dyn);
		}
		free(rpnt);
	}


	if (_dl_debug_addr) {
		dl_brk = (void (*)(void)) _dl_debug_addr->r_brk;
		if (dl_brk != NULL) {
			_dl_debug_addr->r_state = RT_DELETE;
			(*dl_brk) ();

			_dl_debug_addr->r_state = RT_CONSISTENT;
			(*dl_brk) ();
		}
	}

	return 0;
}

int dlclose(void *vhandle)
{
	return do_dlclose(vhandle, 1);
}

char *dlerror(void)
{
	const char *retval;

	if (!_dl_error_number)
		return NULL;
	retval = dl_error_names[_dl_error_number];
	_dl_error_number = 0;
	return retval;
}

/*
 * Dump information to stderrr about the current loaded modules
 */
static char *type[] = { "Lib", "Exe", "Int", "Mod" };

int dlinfo(void)
{
	struct elf_resolve *tpnt;
	struct dyn_elf *rpnt, *hpnt;

	fprintf(stderr, "List of loaded modules\n");
	/* First start with a complete list of all of the loaded files. */
	for (tpnt = _dl_loaded_modules; tpnt; tpnt = tpnt->next) {
		fprintf(stderr, "\t%x %x %x %s %d %s\n",
				(unsigned) tpnt->loadaddr, (unsigned) tpnt,
				(unsigned) tpnt->symbol_scope,
				type[tpnt->libtype],
				tpnt->usage_count, tpnt->libname);
	}

	/* Next dump the module list for the application itself */
	fprintf(stderr, "\nModules for application (%x):\n",
			(unsigned) _dl_symbol_tables);
	for (rpnt = _dl_symbol_tables; rpnt; rpnt = rpnt->next)
		fprintf(stderr, "\t%x %s\n", (unsigned) rpnt->dyn, rpnt->dyn->libname);

	for (hpnt = _dl_handles; hpnt; hpnt = hpnt->next_handle) {
		fprintf(stderr, "Modules for handle %x\n", (unsigned) hpnt);
		for (rpnt = hpnt; rpnt; rpnt = rpnt->next)
			fprintf(stderr, "\t%x %s\n", (unsigned) rpnt->dyn,
					rpnt->dyn->libname);
	}
	return 0;
}

int dladdr(const void *__address, Dl_info * __info)
{
	struct elf_resolve *pelf;
	struct elf_resolve *rpnt;

	_dl_map_cache();

	/*
	 * Try and locate the module address is in
	 */
	pelf = NULL;

#if 0
	fprintf(stderr, "dladdr( %x, %x )\n", __address, __info);
#endif

	for (rpnt = _dl_loaded_modules; rpnt; rpnt = rpnt->next) {
		struct elf_resolve *tpnt;

		tpnt = rpnt;
#if 0
		fprintf(stderr, "Module \"%s\" at %x\n",
				tpnt->libname, tpnt->loadaddr);
#endif
		if (tpnt->loadaddr < (ElfW(Addr)) __address
				&& (pelf == NULL || pelf->loadaddr < tpnt->loadaddr)) {
			pelf = tpnt;
		}
	}

	if (!pelf) {
		return 0;
	}

	/*
	 * Try and locate the symbol of address
	 */

	{
		char *strtab;
		Elf32_Sym *symtab;
		int hn, si;
		int sf;
		int sn = 0;
		ElfW(Addr) sa;

		sa = 0;
		symtab = (Elf32_Sym *) (pelf->dynamic_info[DT_SYMTAB] + pelf->loadaddr);
		strtab = (char *) (pelf->dynamic_info[DT_STRTAB] + pelf->loadaddr);

		sf = 0;
		for (hn = 0; hn < pelf->nbucket; hn++) {
			for (si = pelf->elf_buckets[hn]; si; si = pelf->chains[si]) {
				ElfW(Addr) symbol_addr;

				symbol_addr = pelf->loadaddr + symtab[si].st_value;
				if (symbol_addr <= (ElfW(Addr))__address && (!sf || sa < symbol_addr)) {
					sa = symbol_addr;
					sn = si;
					sf = 1;
				}
#if 0
				fprintf(stderr, "Symbol \"%s\" at %x\n",
						strtab + symtab[si].st_name, symbol_addr);
#endif
			}
		}

		if (sf) {
			__info->dli_fname = pelf->libname;
			__info->dli_fbase = (void *)pelf->loadaddr;
			__info->dli_sname = strtab + symtab[sn].st_name;
			__info->dli_saddr = (void *)sa;
		}
		return 1;
	}
}