From 00299479ab6fc8dfc4f316b82debb3caed922a93 Mon Sep 17 00:00:00 2001
From: Liam <byteslice@airmail.cc>
Date: Mon, 1 Aug 2022 17:19:23 -0400
Subject: [PATCH] core/loader: remove ELF loader

---
 src/core/CMakeLists.txt    |   2 -
 src/core/loader/elf.cpp    | 263 -------------------------------------
 src/core/loader/elf.h      |  36 -----
 src/core/loader/loader.cpp |  11 --
 src/core/loader/loader.h   |   1 -
 5 files changed, 313 deletions(-)
 delete mode 100644 src/core/loader/elf.cpp
 delete mode 100644 src/core/loader/elf.h

diff --git a/src/core/CMakeLists.txt b/src/core/CMakeLists.txt
index 40b1ea4a2..9dbe5bdca 100644
--- a/src/core/CMakeLists.txt
+++ b/src/core/CMakeLists.txt
@@ -727,8 +727,6 @@ add_library(core STATIC
     internal_network/sockets.h
     loader/deconstructed_rom_directory.cpp
     loader/deconstructed_rom_directory.h
-    loader/elf.cpp
-    loader/elf.h
     loader/kip.cpp
     loader/kip.h
     loader/loader.cpp
diff --git a/src/core/loader/elf.cpp b/src/core/loader/elf.cpp
deleted file mode 100644
index dfb10c34f..000000000
--- a/src/core/loader/elf.cpp
+++ /dev/null
@@ -1,263 +0,0 @@
-// SPDX-FileCopyrightText: 2013 Dolphin Emulator Project
-// SPDX-FileCopyrightText: 2014 Citra Emulator Project
-// SPDX-License-Identifier: GPL-2.0-or-later
-
-#include <cstring>
-#include <memory>
-#include "common/common_funcs.h"
-#include "common/common_types.h"
-#include "common/elf.h"
-#include "common/logging/log.h"
-#include "core/hle/kernel/code_set.h"
-#include "core/hle/kernel/k_page_table.h"
-#include "core/hle/kernel/k_process.h"
-#include "core/loader/elf.h"
-#include "core/memory.h"
-
-using namespace Common::ELF;
-
-////////////////////////////////////////////////////////////////////////////////////////////////////
-// ElfReader class
-
-typedef int SectionID;
-
-class ElfReader {
-private:
-    char* base;
-    u32* base32;
-
-    Elf32_Ehdr* header;
-    Elf32_Phdr* segments;
-    Elf32_Shdr* sections;
-
-    u32* sectionAddrs;
-    bool relocate;
-    VAddr entryPoint;
-
-public:
-    explicit ElfReader(void* ptr);
-
-    u32 Read32(int off) const {
-        return base32[off >> 2];
-    }
-
-    // Quick accessors
-    u16 GetType() const {
-        return header->e_type;
-    }
-    u16 GetMachine() const {
-        return header->e_machine;
-    }
-    VAddr GetEntryPoint() const {
-        return entryPoint;
-    }
-    u32 GetFlags() const {
-        return (u32)(header->e_flags);
-    }
-    Kernel::CodeSet LoadInto(VAddr vaddr);
-
-    int GetNumSegments() const {
-        return (int)(header->e_phnum);
-    }
-    int GetNumSections() const {
-        return (int)(header->e_shnum);
-    }
-    const u8* GetPtr(int offset) const {
-        return (u8*)base + offset;
-    }
-    const char* GetSectionName(int section) const;
-    const u8* GetSectionDataPtr(int section) const {
-        if (section < 0 || section >= header->e_shnum)
-            return nullptr;
-        if (sections[section].sh_type != ElfShtNobits)
-            return GetPtr(sections[section].sh_offset);
-        else
-            return nullptr;
-    }
-    bool IsCodeSection(int section) const {
-        return sections[section].sh_type == ElfShtProgBits;
-    }
-    const u8* GetSegmentPtr(int segment) {
-        return GetPtr(segments[segment].p_offset);
-    }
-    u32 GetSectionAddr(SectionID section) const {
-        return sectionAddrs[section];
-    }
-    unsigned int GetSectionSize(SectionID section) const {
-        return sections[section].sh_size;
-    }
-    SectionID GetSectionByName(const char* name, int firstSection = 0) const; //-1 for not found
-
-    bool DidRelocate() const {
-        return relocate;
-    }
-};
-
-ElfReader::ElfReader(void* ptr) {
-    base = (char*)ptr;
-    base32 = (u32*)ptr;
-    header = (Elf32_Ehdr*)ptr;
-
-    segments = (Elf32_Phdr*)(base + header->e_phoff);
-    sections = (Elf32_Shdr*)(base + header->e_shoff);
-
-    entryPoint = header->e_entry;
-}
-
-const char* ElfReader::GetSectionName(int section) const {
-    if (sections[section].sh_type == ElfShtNull)
-        return nullptr;
-
-    int name_offset = sections[section].sh_name;
-    const char* ptr = reinterpret_cast<const char*>(GetSectionDataPtr(header->e_shstrndx));
-
-    if (ptr)
-        return ptr + name_offset;
-
-    return nullptr;
-}
-
-Kernel::CodeSet ElfReader::LoadInto(VAddr vaddr) {
-    LOG_DEBUG(Loader, "String section: {}", header->e_shstrndx);
-
-    // Should we relocate?
-    relocate = (header->e_type != ElfTypeExec);
-
-    if (relocate) {
-        LOG_DEBUG(Loader, "Relocatable module");
-        entryPoint += vaddr;
-    } else {
-        LOG_DEBUG(Loader, "Prerelocated executable");
-    }
-    LOG_DEBUG(Loader, "{} segments:", header->e_phnum);
-
-    // First pass : Get the bits into RAM
-    const VAddr base_addr = relocate ? vaddr : 0;
-
-    u64 total_image_size = 0;
-    for (unsigned int i = 0; i < header->e_phnum; ++i) {
-        const Elf32_Phdr* p = &segments[i];
-        if (p->p_type == ElfPtLoad) {
-            total_image_size += (p->p_memsz + 0xFFF) & ~0xFFF;
-        }
-    }
-
-    Kernel::PhysicalMemory program_image(total_image_size);
-    std::size_t current_image_position = 0;
-
-    Kernel::CodeSet codeset;
-
-    for (unsigned int i = 0; i < header->e_phnum; ++i) {
-        const Elf32_Phdr* p = &segments[i];
-        LOG_DEBUG(Loader, "Type: {} Vaddr: {:08X} Filesz: {:08X} Memsz: {:08X} ", p->p_type,
-                  p->p_vaddr, p->p_filesz, p->p_memsz);
-
-        if (p->p_type == ElfPtLoad) {
-            Kernel::CodeSet::Segment* codeset_segment;
-            u32 permission_flags = p->p_flags & (ElfPfRead | ElfPfWrite | ElfPfExec);
-            if (permission_flags == (ElfPfRead | ElfPfExec)) {
-                codeset_segment = &codeset.CodeSegment();
-            } else if (permission_flags == (ElfPfRead)) {
-                codeset_segment = &codeset.RODataSegment();
-            } else if (permission_flags == (ElfPfRead | ElfPfWrite)) {
-                codeset_segment = &codeset.DataSegment();
-            } else {
-                LOG_ERROR(Loader, "Unexpected ELF PT_LOAD segment id {} with flags {:X}", i,
-                          p->p_flags);
-                continue;
-            }
-
-            if (codeset_segment->size != 0) {
-                LOG_ERROR(Loader,
-                          "ELF has more than one segment of the same type. Skipping extra "
-                          "segment (id {})",
-                          i);
-                continue;
-            }
-
-            const VAddr segment_addr = base_addr + p->p_vaddr;
-            const u32 aligned_size = (p->p_memsz + 0xFFF) & ~0xFFF;
-
-            codeset_segment->offset = current_image_position;
-            codeset_segment->addr = segment_addr;
-            codeset_segment->size = aligned_size;
-
-            std::memcpy(program_image.data() + current_image_position, GetSegmentPtr(i),
-                        p->p_filesz);
-            current_image_position += aligned_size;
-        }
-    }
-
-    codeset.entrypoint = base_addr + header->e_entry;
-    codeset.memory = std::move(program_image);
-
-    LOG_DEBUG(Loader, "Done loading.");
-
-    return codeset;
-}
-
-SectionID ElfReader::GetSectionByName(const char* name, int firstSection) const {
-    for (int i = firstSection; i < header->e_shnum; i++) {
-        const char* secname = GetSectionName(i);
-
-        if (secname != nullptr && strcmp(name, secname) == 0)
-            return i;
-    }
-    return -1;
-}
-
-////////////////////////////////////////////////////////////////////////////////////////////////////
-// Loader namespace
-
-namespace Loader {
-
-AppLoader_ELF::AppLoader_ELF(FileSys::VirtualFile file_) : AppLoader(std::move(file_)) {}
-
-FileType AppLoader_ELF::IdentifyType(const FileSys::VirtualFile& elf_file) {
-    static constexpr u16 ELF_MACHINE_ARM{0x28};
-
-    u32 magic = 0;
-    if (4 != elf_file->ReadObject(&magic)) {
-        return FileType::Error;
-    }
-
-    u16 machine = 0;
-    if (2 != elf_file->ReadObject(&machine, 18)) {
-        return FileType::Error;
-    }
-
-    if (Common::MakeMagic('\x7f', 'E', 'L', 'F') == magic && ELF_MACHINE_ARM == machine) {
-        return FileType::ELF;
-    }
-
-    return FileType::Error;
-}
-
-AppLoader_ELF::LoadResult AppLoader_ELF::Load(Kernel::KProcess& process,
-                                              [[maybe_unused]] Core::System& system) {
-    if (is_loaded) {
-        return {ResultStatus::ErrorAlreadyLoaded, {}};
-    }
-
-    std::vector<u8> buffer = file->ReadAllBytes();
-    if (buffer.size() != file->GetSize()) {
-        return {ResultStatus::ErrorIncorrectELFFileSize, {}};
-    }
-
-    const VAddr base_address = process.PageTable().GetCodeRegionStart();
-    ElfReader elf_reader(&buffer[0]);
-    Kernel::CodeSet codeset = elf_reader.LoadInto(base_address);
-    const VAddr entry_point = codeset.entrypoint;
-
-    // Setup the process code layout
-    if (process.LoadFromMetadata(FileSys::ProgramMetadata::GetDefault(), buffer.size()).IsError()) {
-        return {ResultStatus::ErrorNotInitialized, {}};
-    }
-
-    process.LoadModule(std::move(codeset), entry_point);
-
-    is_loaded = true;
-    return {ResultStatus::Success, LoadParameters{48, Core::Memory::DEFAULT_STACK_SIZE}};
-}
-
-} // namespace Loader
diff --git a/src/core/loader/elf.h b/src/core/loader/elf.h
deleted file mode 100644
index acd33dc3d..000000000
--- a/src/core/loader/elf.h
+++ /dev/null
@@ -1,36 +0,0 @@
-// SPDX-FileCopyrightText: 2013 Dolphin Emulator Project
-// SPDX-FileCopyrightText: 2014 Citra Emulator Project
-// SPDX-License-Identifier: GPL-2.0-or-later
-
-#pragma once
-
-#include "core/loader/loader.h"
-
-namespace Core {
-class System;
-}
-
-namespace Loader {
-
-/// Loads an ELF/AXF file
-class AppLoader_ELF final : public AppLoader {
-public:
-    explicit AppLoader_ELF(FileSys::VirtualFile file);
-
-    /**
-     * Identifies whether or not the given file is an ELF file.
-     *
-     * @param elf_file The file to identify.
-     *
-     * @return FileType::ELF, or FileType::Error if the file is not an ELF file.
-     */
-    static FileType IdentifyType(const FileSys::VirtualFile& elf_file);
-
-    FileType GetFileType() const override {
-        return IdentifyType(file);
-    }
-
-    LoadResult Load(Kernel::KProcess& process, Core::System& system) override;
-};
-
-} // namespace Loader
diff --git a/src/core/loader/loader.cpp b/src/core/loader/loader.cpp
index 994ee891f..104d16efa 100644
--- a/src/core/loader/loader.cpp
+++ b/src/core/loader/loader.cpp
@@ -12,7 +12,6 @@
 #include "core/core.h"
 #include "core/hle/kernel/k_process.h"
 #include "core/loader/deconstructed_rom_directory.h"
-#include "core/loader/elf.h"
 #include "core/loader/kip.h"
 #include "core/loader/nax.h"
 #include "core/loader/nca.h"
@@ -39,8 +38,6 @@ std::optional<FileType> IdentifyFileLoader(FileSys::VirtualFile file) {
 FileType IdentifyFile(FileSys::VirtualFile file) {
     if (const auto romdir_type = IdentifyFileLoader<AppLoader_DeconstructedRomDirectory>(file)) {
         return *romdir_type;
-    } else if (const auto elf_type = IdentifyFileLoader<AppLoader_ELF>(file)) {
-        return *elf_type;
     } else if (const auto nso_type = IdentifyFileLoader<AppLoader_NSO>(file)) {
         return *nso_type;
     } else if (const auto nro_type = IdentifyFileLoader<AppLoader_NRO>(file)) {
@@ -69,8 +66,6 @@ FileType GuessFromFilename(const std::string& name) {
     const std::string extension =
         Common::ToLower(std::string(Common::FS::GetExtensionFromFilename(name)));
 
-    if (extension == "elf")
-        return FileType::ELF;
     if (extension == "nro")
         return FileType::NRO;
     if (extension == "nso")
@@ -89,8 +84,6 @@ FileType GuessFromFilename(const std::string& name) {
 
 std::string GetFileTypeString(FileType type) {
     switch (type) {
-    case FileType::ELF:
-        return "ELF";
     case FileType::NRO:
         return "NRO";
     case FileType::NSO:
@@ -208,10 +201,6 @@ static std::unique_ptr<AppLoader> GetFileLoader(Core::System& system, FileSys::V
                                                 FileType type, u64 program_id,
                                                 std::size_t program_index) {
     switch (type) {
-    // Standard ELF file format.
-    case FileType::ELF:
-        return std::make_unique<AppLoader_ELF>(std::move(file));
-
     // NX NSO file format.
     case FileType::NSO:
         return std::make_unique<AppLoader_NSO>(std::move(file));
diff --git a/src/core/loader/loader.h b/src/core/loader/loader.h
index 7bf4faaf1..7b43f70ed 100644
--- a/src/core/loader/loader.h
+++ b/src/core/loader/loader.h
@@ -34,7 +34,6 @@ namespace Loader {
 enum class FileType {
     Error,
     Unknown,
-    ELF,
     NSO,
     NRO,
     NCA,