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/*
* Copyright (c) 2019-2020, Andrew Kaster <andrewdkaster@gmail.com>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <AK/String.h>
#include <LibELF/AuxiliaryVector.h>
#include <dlfcn.h>
#include <stdio.h>
int main(int argc, char** argv, char** envp)
{
for (int i = 0; i < argc; ++i)
outln("argv[{}]: {}", i, argv[i]);
char** env;
for (env = envp; *env; ++env)
outln("env: {}", *env);
for (auxv_t* auxvp = (auxv_t*)++env; auxvp->a_type != AT_NULL; ++auxvp) {
outln("AuxVal: Type={}, Val/Ptr={}", auxvp->a_type, auxvp->a_un.a_ptr);
if (auxvp->a_type == AT_PLATFORM) {
outln(" Platform: {}", (char*)auxvp->a_un.a_ptr);
} else if (auxvp->a_type == AT_EXECFN) {
outln(" Filename: {}", (char*)auxvp->a_un.a_ptr);
} else if (auxvp->a_type == AT_RANDOM) {
auto byte_ptr = (uint8_t*)auxvp->a_un.a_ptr;
outln(" My Random bytes are: ");
for (size_t i = 0; i < 16; ++i)
out("{:#02x} ", byte_ptr[i]);
outln();
}
}
void* handle = dlopen("/usr/lib/libDynamicLib.so", RTLD_LAZY | RTLD_GLOBAL);
if (!handle) {
warnln("Failed to dlopen! {}", dlerror());
return 1;
}
// Test getting an external variable from the library and read it out
int* ptr_global = (int*)dlsym(handle, "global_lib_variable");
if (!ptr_global) {
warnln("Failed to dlsym for \"global_lib_variable\"! {}", dlerror());
return 2;
}
outln("Found global lib variable address: {}", ptr_global);
outln("Global lib variable is {}", *ptr_global);
// Test getting a method from the library and calling it
void (*lib_func)(void) = (void (*)(void))dlsym(handle, "global_lib_function");
outln("Found global lib function address: {}", lib_func);
if (!lib_func) {
warnln("Failed to dlsym for \"global_lib_function\"! {}", dlerror());
return 2;
}
lib_func();
outln("I think I called my lib function!");
// Test getting a method that takes and returns arguments now
const char* (*other_func)(int) = (const char* (*)(int))dlsym(handle, "other_lib_function");
outln("Found other lib function address {}", other_func);
if (!other_func) {
warnln("Failed to dlsym for \"other_lib_function\"! {}", dlerror());
return 2;
}
// Call it twice with different arguments
String formatted_result = other_func(10);
outln("({} + {} = {}) {}", *ptr_global, 10, *ptr_global + 10, formatted_result);
*ptr_global = 17;
formatted_result = other_func(5);
outln("({} + {} = {}) {}", *ptr_global, 5, *ptr_global + 5, formatted_result);
int ret = dlclose(handle);
if (ret < 0) {
warnln("Failed to dlclose! {}", dlerror());
return 3;
}
outln("Bye for now!");
return 0;
}
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