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/*
* Copyright (C) 2014 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <dlfcn.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
static uintptr_t g_flag = 0;
static void __attribute__((constructor)) init_flag() {
g_flag = reinterpret_cast<uintptr_t>(dlsym(RTLD_DEFAULT, "dlsym"));
}
static const char* is_ctor_called() __attribute__ ((ifunc("is_ctor_called_ifun")));
extern "C" const char* foo() __attribute__ ((ifunc ("foo_ifunc")));
// Static linker creates GLOBAL/IFUNC symbol and JUMP_SLOT relocation type for plt segment
extern "C" const char* is_ctor_called_jump_slot() __attribute__ ((ifunc("is_ctor_called_ifun")));
extern "C" const char* is_ctor_called_irelative() {
// Call internal ifunc-resolved function with IRELATIVE reloc
return is_ctor_called();
}
extern "C" const char* return_true() {
return "true";
}
extern "C" const char* return_false() {
return "false";
}
extern "C" const char* f1() {
return "unset";
}
extern "C" const char* f2() {
return "set";
}
typedef const char* (*fn_ptr)();
extern "C" fn_ptr is_ctor_called_ifun() {
return g_flag == 0 ? return_false : return_true;
}
extern "C" fn_ptr foo_ifunc() {
char* choice = getenv("IFUNC_CHOICE");
return choice == nullptr ? f1 : f2;
}
extern "C" const char* foo_library() {
return foo();
}
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