/* check which symbols the program looks up */
void *
dlsym(void *handle, const char *symbol)
{
static void *(*orig_dlsym)(void *, const char *);
void *orig_ptr, *ptr = NULL;
if (orig_dlsym == NULL)
orig_dlsym = _dl_sym(RTLD_NEXT, "dlsym", dlsym);
if (!_env_ignored) {
/* try to resolve the symbol to an internal one first to avoid issues
* with dlerror().
*/
ptr = _env_dump_resolve_local_symbol_by_name(symbol);
/* resolve the symbol as expected by the client */
orig_ptr = orig_dlsym(handle, symbol);
if (!orig_ptr)
return orig_ptr;
/* add the symbol to our DB */
_env_dump_replace_symbol(symbol, orig_ptr);
if (ptr)
return ptr;
else
return orig_ptr;
} else
return orig_dlsym(handle, symbol);
}
void *
_env_dump_resolve_symbol_by_name(const char *symbol)
{
void *ret = NULL, *tmp_ret = NULL;
void *(*orig_dlsym)(void *handle, const char *symbol);
int i;
pthread_mutex_lock(&symbols_mp);
/* first check in our internal DB */
for (i = 0; i < symbols_count; i++) {
if (symbols[i].name && strcmp(symbols[i].name, symbol) == 0) {
ret = symbols[i].ptr;
break;
}
}
pthread_mutex_unlock(&symbols_mp);
if (ret)
return ret;
/* Then try to see if there is another version somewhere else */
orig_dlsym = _env_dump_resolve_symbol_by_id(SYMB_DLSYM);
ret = orig_dlsym(RTLD_NEXT, symbol);
if (ret == NULL) {
/* Try to resolve the symbol from the local handles */
pthread_mutex_lock(&found_so_list_mp);
for (i = 0; i < dlopen_local_handles_count; i++) {
tmp_ret = orig_dlsym(dlopen_local_handles[i], symbol);
if (tmp_ret) {
if (ret == NULL || ret == tmp_ret)
ret = tmp_ret;
else {
fprintf(env_file, "WARNING, found multiple candidates for "
"the symbol '%s'\n", symbol);
}
}
}
pthread_mutex_unlock(&found_so_list_mp);
}
return ret;
}
void *
_env_dump_resolve_local_symbol_by_name(const char *symbol)
{
static void *(*orig_dlsym)(void *, const char *);
static void *handle_env_dump;
if (orig_dlsym == NULL)
orig_dlsym = _dl_sym(RTLD_NEXT, "dlsym", dlsym);
if (handle_env_dump == NULL ) {
void *(*orig_dlopen)(const char *, int);
char *fullpath = find_Linked_library("env_dump.so");
orig_dlopen = _dl_sym(RTLD_NEXT, "dlopen", dlsym);
handle_env_dump = orig_dlopen(fullpath, RTLD_LAZY);
free(fullpath);
}
return orig_dlsym(handle_env_dump, symbol);
}
//void *dlsym(void *handle,const char *symbol)
HOOK_DEF(void*, dlsym, void *handle, char *symbol) {
LOGD("dlsym : %p %s.", handle, symbol);
return orig_dlsym(handle, symbol);
}