CustomRPXLoader/src/main.cpp

#include <stdint.h>
#include <coreinit/cache.h>
#include <coreinit/dynload.h>
#include <sysapp/launch.h>
#include <nsysnet/socket.h>
#include <proc_ui/procui.h>
#include <coreinit/foreground.h>

#include "ElfUtils.h"
#include "module/ModuleData.h"
#include "module/ModuleDataFactory.h"
#include "common/module_defines.h"

#include "main.h"
#include "kernel.h"
#include "dynamic.h"
#include "utils/logger.h"
#include "utils/utils.h"
#include "utils/sd_fat_devoptab.h"

#define gModuleData ((module_information_t *) (0x00880000))
static_assert(sizeof(module_information_t) <= 0x80000);

bool doRelocation(std::vector<RelocationData *> &relocData, relocation_trampolin_entry_t * tramp_data, uint32_t tramp_length);


bool CheckRunning() {

    switch(ProcUIProcessMessages(true)) {
    case PROCUI_STATUS_EXITING: {
        return false;
    }
    case PROCUI_STATUS_RELEASE_FOREGROUND: {
        ProcUIDrawDoneRelease();
        break;
    }
    case PROCUI_STATUS_IN_FOREGROUND: {
        break;
    }
    case PROCUI_STATUS_IN_BACKGROUND:
    default:
        break;
    }
    return true;
}

extern "C" int _start(int argc, char **argv) {
    doKernelSetup();
    InitFunctionPointers();

    socket_lib_init();
    log_init();

    int res = 0;
    if((res = mount_sd_fat("sd")) >= 0) {
        DEBUG_FUNCTION_LINE("Mounted sd card\n");

        uint32_t ApplicationMemoryEnd;

        asm volatile("lis %0, __CODE_END@h; ori %0, %0, __CODE_END@l" : "=r" (ApplicationMemoryEnd));
        ApplicationMemoryEnd = (ApplicationMemoryEnd + 0x10000) & 0xFFFF0000;
        ModuleData * moduleData = ModuleDataFactory::load("sd:/wiiu/payload.rpx", ApplicationMemoryEnd, 0x01000000 - ApplicationMemoryEnd, gModuleData->trampolines, DYN_LINK_TRAMPOLIN_LIST_LENGTH);
        if(moduleData != NULL) {
            DEBUG_FUNCTION_LINE("Loaded module data\n");
            std::vector<RelocationData *> relocData = moduleData->getRelocationDataList();
            if(!doRelocation(relocData, gModuleData->trampolines,DYN_LINK_TRAMPOLIN_LIST_LENGTH)) {
                DEBUG_FUNCTION_LINE("relocations failed\n");
            }
            if(moduleData->getBSSAddr() != 0) {
                DEBUG_FUNCTION_LINE("memset .bss %08X (%d)\n", moduleData->getBSSAddr(), moduleData->getBSSSize());
                memset((void*)moduleData->getBSSAddr(), 0, moduleData->getBSSSize());
            }
            if(moduleData->getSBSSAddr() != 0) {
                DEBUG_FUNCTION_LINE("memset .sbss %08X (%d)\n", moduleData->getSBSSAddr(), moduleData->getSBSSSize());
                memset((void*)moduleData->getSBSSAddr(), 0, moduleData->getSBSSSize());
            }
            DCFlushRange((void*)0x00800000, 0x00800000);
            ICInvalidateRange((void*)0x00800000, 0x00800000);
            DEBUG_FUNCTION_LINE("New entrypoint: %08X\n", moduleData->getEntrypoint());
            ((int (*)(int, char **))moduleData->getEntrypoint())(argc, argv);
            delete moduleData;
        } else {
            DEBUG_FUNCTION_LINE("Failed to load module\n");
        }
    } else {
        DEBUG_FUNCTION_LINE("Mounted sd card failed %d.\n", res);
    }

    SYSLaunchMenu();

    ProcUIInit(OSSavesDone_ReadyToRelease);
    DEBUG_FUNCTION_LINE("In ProcUI loop\n");
    while(CheckRunning()) {
        // wait.
        OSSleepTicks(OSMillisecondsToTicks(100));
    }
    ProcUIShutdown();

    return 0;
}


bool doRelocation(std::vector<RelocationData *> &relocData, relocation_trampolin_entry_t * tramp_data, uint32_t tramp_length) {
    for (auto const& curReloc : relocData) {
        RelocationData * cur = curReloc;
        std::string functionName = cur->getName();
        std::string rplName = cur->getImportRPLInformation()->getName();
        int32_t isData = cur->getImportRPLInformation()->isData();
        OSDynLoad_Module rplHandle = 0;
        OSDynLoad_Acquire(rplName.c_str(), &rplHandle);

        uint32_t functionAddress = 0;
        OSDynLoad_FindExport(rplHandle, isData, functionName.c_str(), (void**) &functionAddress);
        if(functionAddress == 0) {
            return false;
        }
        if(!ElfUtils::elfLinkOne(cur->getType(), cur->getOffset(), cur->getAddend(), (uint32_t) cur->getDestination(), functionAddress, tramp_data, tramp_length, RELOC_TYPE_IMPORT)) {
            DEBUG_FUNCTION_LINE("Relocation failed\n");
            return false;
        }
    }

    DCFlushRange(tramp_data, tramp_length * sizeof(relocation_trampolin_entry_t));
    ICInvalidateRange(tramp_data, tramp_length * sizeof(relocation_trampolin_entry_t));
    return true;
}