From 7889cafc76ac99b8509fa3cd1558a09f8a7e5f91 Mon Sep 17 00:00:00 2001
From: bunnei <ericbunnie@gmail.com>
Date: Wed, 18 Jun 2014 18:58:09 -0400
Subject: [PATCH] Loader: Implemented AppLoader interface for abstracting
 application loading.

- Various cleanups/refactorings to Loader, ELF, and NCCH modules.
- Added AppLoader interface to ELF and NCCH.
- Updated Qt/GLFW frontends to check AppLoader ResultStatus.

NCCH: Removed extra qualification typos.

Loader: Removed unnecessary #include's.

NCCH: Improved readability of memcmp statements.

NCCH: Added missing space.

Elf: Removed unnecessary usage of unique_ptr.

Loader: Removed unnecessary usage of unique_ptr.
---
 src/citra/citra.cpp        |  25 ++-
 src/citra_qt/main.cpp      |   7 +-
 src/core/loader/elf.cpp    | 318 ++++++++++++++++++++++++++++++-------
 src/core/loader/elf.h      | 232 ++-------------------------
 src/core/loader/loader.cpp |  63 ++++----
 src/core/loader/loader.h   | 103 ++++++++++--
 src/core/loader/ncch.cpp   | 312 +++++++++++++-----------------------
 src/core/loader/ncch.h     | 181 ++++++++++++++++++++-
 8 files changed, 690 insertions(+), 551 deletions(-)

diff --git a/src/citra/citra.cpp b/src/citra/citra.cpp
index f6bb10f290..036af37354 100644
--- a/src/citra/citra.cpp
+++ b/src/citra/citra.cpp
@@ -16,28 +16,21 @@
 
 /// Application entry point
 int __cdecl main(int argc, char **argv) {
-    std::string program_dir = File::GetCurrentDir();
-
     LogManager::Init();
 
+    if (argc < 2) {
+        ERROR_LOG(BOOT, "Failed to load ROM: No ROM specified");
+        return -1;
+    }
+
+    std::string boot_filename = argv[1];
     EmuWindow_GLFW* emu_window = new EmuWindow_GLFW;
 
     System::Init(emu_window);
 
-    std::string boot_filename;
-
-    if (argc < 2) {
-        ERROR_LOG(BOOT, "Failed to load ROM: No ROM specified");
-    }
-    else {
-        boot_filename = argv[1];
-    }
-    std::string error_str;
-
-    bool res = Loader::LoadFile(boot_filename, &error_str);
-
-    if (!res) {
-        ERROR_LOG(BOOT, "Failed to load ROM: %s", error_str.c_str());
+    if (Loader::ResultStatus::Success != Loader::LoadFile(boot_filename)) {
+        ERROR_LOG(BOOT, "Failed to load ROM!");
+        return -1;
     }
 
     Core::RunLoop();
diff --git a/src/citra_qt/main.cpp b/src/citra_qt/main.cpp
index cff0b6a2a3..0bcce7d167 100644
--- a/src/citra_qt/main.cpp
+++ b/src/citra_qt/main.cpp
@@ -135,11 +135,8 @@ void GMainWindow::BootGame(const char* filename)
 
     // Load a game or die...
     std::string boot_filename = filename;
-    std::string error_str;
-    bool res = Loader::LoadFile(boot_filename, &error_str);
-
-    if (!res) {
-        ERROR_LOG(BOOT, "Failed to load ROM: %s", error_str.c_str());
+    if (Loader::ResultStatus::Success != Loader::LoadFile(boot_filename)) {
+        ERROR_LOG(BOOT, "Failed to load ROM!");
     }
 
     disasmWidget->Init();
diff --git a/src/core/loader/elf.cpp b/src/core/loader/elf.cpp
index f933548170..065601546a 100644
--- a/src/core/loader/elf.cpp
+++ b/src/core/loader/elf.cpp
@@ -3,6 +3,7 @@
 // Refer to the license.txt file included.
 
 #include <string>
+#include <memory>
 
 #include "common/common.h"
 #include "common/file_util.h"
@@ -12,6 +13,220 @@
 #include "core/loader/elf.h"
 #include "core/hle/kernel/kernel.h"
 
+////////////////////////////////////////////////////////////////////////////////////////////////////
+// ELF Header Constants
+
+// File type
+enum ElfType {
+    ET_NONE = 0,
+    ET_REL = 1,
+    ET_EXEC = 2,
+    ET_DYN = 3,
+    ET_CORE = 4,
+    ET_LOPROC = 0xFF00,
+    ET_HIPROC = 0xFFFF,
+};
+
+// Machine/Architecture
+enum ElfMachine {
+    EM_NONE = 0,
+    EM_M32 = 1,
+    EM_SPARC = 2,
+    EM_386 = 3,
+    EM_68K = 4,
+    EM_88K = 5,
+    EM_860 = 7,
+    EM_MIPS = 8
+};
+
+// File version
+#define EV_NONE    0
+#define EV_CURRENT 1
+
+// Identification index
+#define EI_MAG0    0
+#define EI_MAG1    1
+#define EI_MAG2    2
+#define EI_MAG3    3
+#define EI_CLASS   4
+#define EI_DATA    5
+#define EI_VERSION 6
+#define EI_PAD     7
+#define EI_NIDENT 16
+
+// Magic number
+#define ELFMAG0 0x7F
+#define ELFMAG1  'E'
+#define ELFMAG2  'L'
+#define ELFMAG3  'F'
+
+// Sections constants
+
+// Section types
+#define SHT_NULL            0
+#define SHT_PROGBITS        1
+#define SHT_SYMTAB          2
+#define SHT_STRTAB          3
+#define SHT_RELA            4
+#define SHT_HASH            5
+#define SHT_DYNAMIC         6
+#define SHT_NOTE            7
+#define SHT_NOBITS          8
+#define SHT_REL             9
+#define SHT_SHLIB          10
+#define SHT_DYNSYM         11
+#define SHT_LOPROC 0x70000000
+#define SHT_HIPROC 0x7FFFFFFF
+#define SHT_LOUSER 0x80000000
+#define SHT_HIUSER 0xFFFFFFFF
+
+// Section flags
+enum ElfSectionFlags
+{
+    SHF_WRITE = 0x1,
+    SHF_ALLOC = 0x2,
+    SHF_EXECINSTR = 0x4,
+    SHF_MASKPROC = 0xF0000000,
+};
+
+// Segment types
+#define PT_NULL             0
+#define PT_LOAD             1
+#define PT_DYNAMIC          2
+#define PT_INTERP           3
+#define PT_NOTE             4
+#define PT_SHLIB            5
+#define PT_PHDR             6
+#define PT_LOPROC  0x70000000
+#define PT_HIPROC  0x7FFFFFFF
+
+typedef unsigned int  Elf32_Addr;
+typedef unsigned short Elf32_Half;
+typedef unsigned int  Elf32_Off;
+typedef signed   int  Elf32_Sword;
+typedef unsigned int  Elf32_Word;
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+// ELF file header
+
+struct Elf32_Ehdr {
+    unsigned char e_ident[EI_NIDENT];
+    Elf32_Half    e_type;
+    Elf32_Half    e_machine;
+    Elf32_Word    e_version;
+    Elf32_Addr    e_entry;
+    Elf32_Off     e_phoff;
+    Elf32_Off     e_shoff;
+    Elf32_Word    e_flags;
+    Elf32_Half    e_ehsize;
+    Elf32_Half    e_phentsize;
+    Elf32_Half    e_phnum;
+    Elf32_Half    e_shentsize;
+    Elf32_Half    e_shnum;
+    Elf32_Half    e_shstrndx;
+};
+
+// Section header
+struct Elf32_Shdr {
+    Elf32_Word sh_name;
+    Elf32_Word sh_type;
+    Elf32_Word sh_flags;
+    Elf32_Addr sh_addr;
+    Elf32_Off  sh_offset;
+    Elf32_Word sh_size;
+    Elf32_Word sh_link;
+    Elf32_Word sh_info;
+    Elf32_Word sh_addralign;
+    Elf32_Word sh_entsize;
+};
+
+// Segment header
+struct Elf32_Phdr {
+    Elf32_Word p_type;
+    Elf32_Off  p_offset;
+    Elf32_Addr p_vaddr;
+    Elf32_Addr p_paddr;
+    Elf32_Word p_filesz;
+    Elf32_Word p_memsz;
+    Elf32_Word p_flags;
+    Elf32_Word p_align;
+};
+
+// Symbol table entry
+struct Elf32_Sym {
+    Elf32_Word    st_name;
+    Elf32_Addr    st_value;
+    Elf32_Word    st_size;
+    unsigned char st_info;
+    unsigned char st_other;
+    Elf32_Half    st_shndx;
+};
+
+// Relocation entries
+struct Elf32_Rel {
+    Elf32_Addr r_offset;
+    Elf32_Word r_info;
+};
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+// 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;
+    u32 entryPoint;
+
+public:
+    ElfReader(void *ptr);
+    ~ElfReader() { }
+
+    u32 Read32(int off) const { return base32[off >> 2]; }
+
+    // Quick accessors
+    ElfType GetType() const { return (ElfType)(header->e_type); }
+    ElfMachine GetMachine() const { return (ElfMachine)(header->e_machine); }
+    u32 GetEntryPoint() const { return entryPoint; }
+    u32 GetFlags() const { return (u32)(header->e_flags); }
+    bool LoadInto(u32 vaddr);
+    bool LoadSymbols();
+
+    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 != SHT_NOBITS)
+            return GetPtr(sections[section].sh_offset);
+        else
+            return nullptr;
+    }
+    bool IsCodeSection(int section) const {
+        return sections[section].sh_type == SHT_PROGBITS;
+    }
+    const u8 *GetSegmentPtr(int segment) {
+        return GetPtr(segments[segment].p_offset);
+    }
+    u32 GetSectionAddr(SectionID section) const { return sectionAddrs[section]; }
+    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() {
+        return relocate;
+    }
+};
+
 ElfReader::ElfReader(void *ptr) {
     base = (char*)ptr;
     base32 = (u32 *)ptr;
@@ -29,28 +244,25 @@ const char *ElfReader::GetSectionName(int section) const {
     if (sections[section].sh_type == SHT_NULL)
         return nullptr;
 
-    int nameOffset = sections[section].sh_name;
+    int name_offset = sections[section].sh_name;
     char *ptr = (char*)GetSectionDataPtr(header->e_shstrndx);
 
     if (ptr)
-        return ptr + nameOffset;
-    else
-        return nullptr;
+        return ptr + name_offset;
+
+    return nullptr;
 }
 
 bool ElfReader::LoadInto(u32 vaddr) {
     DEBUG_LOG(MASTER_LOG, "String section: %i", header->e_shstrndx);
 
     // Should we relocate?
-    bRelocate = (header->e_type != ET_EXEC);
+    relocate = (header->e_type != ET_EXEC);
 
-    if (bRelocate)
-    {
+    if (relocate) {
         DEBUG_LOG(MASTER_LOG, "Relocatable module");
         entryPoint += vaddr;
-    }
-    else
-    {
+    } else {
         DEBUG_LOG(MASTER_LOG, "Prerelocated executable");
     }
 
@@ -58,17 +270,14 @@ bool ElfReader::LoadInto(u32 vaddr) {
 
     // First pass : Get the bits into RAM
     u32 segmentVAddr[32];
+    u32 baseAddress = relocate ? vaddr : 0;
 
-    u32 baseAddress = bRelocate ? vaddr : 0;
-
-    for (int i = 0; i < header->e_phnum; i++)
-    {
+    for (int i = 0; i < header->e_phnum; i++) {
         Elf32_Phdr *p = segments + i;
 
         INFO_LOG(MASTER_LOG, "Type: %i Vaddr: %08x Filesz: %i Memsz: %i ", p->p_type, p->p_vaddr, p->p_filesz, p->p_memsz);
 
-        if (p->p_type == PT_LOAD)
-        {
+        if (p->p_type == PT_LOAD) {
             segmentVAddr[i] = baseAddress + p->p_vaddr;
             u32 writeAddr = segmentVAddr[i];
 
@@ -78,27 +287,19 @@ bool ElfReader::LoadInto(u32 vaddr) {
             u32 dstSize = p->p_memsz;
             u32 *s = (u32*)src;
             u32 *d = (u32*)dst;
-            for (int j = 0; j < (int)(srcSize + 3) / 4; j++)
-            {
-                *d++ = /*_byteswap_ulong*/(*s++);
-            }
-            if (srcSize < dstSize)
-            {
-                //memset(dst + srcSize, 0, dstSize-srcSize); //zero out bss
+            for (int j = 0; j < (int)(srcSize + 3) / 4; j++) {
+                *d++ = (*s++);
             }
             INFO_LOG(MASTER_LOG, "Loadable Segment Copied to %08x, size %08x", writeAddr, p->p_memsz);
         }
     }
 
-
     INFO_LOG(MASTER_LOG, "Done loading.");
     return true;
 }
 
-SectionID ElfReader::GetSectionByName(const char *name, int firstSection) const
-{
-    for (int i = firstSection; i < header->e_shnum; i++)
-    {
+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)
@@ -107,25 +308,21 @@ SectionID ElfReader::GetSectionByName(const char *name, int firstSection) const
     return -1;
 }
 
-bool ElfReader::LoadSymbols()
-{
+bool ElfReader::LoadSymbols() {
     bool hasSymbols = false;
     SectionID sec = GetSectionByName(".symtab");
-    if (sec != -1)
-    {
+    if (sec != -1) {
         int stringSection = sections[sec].sh_link;
         const char *stringBase = (const char *)GetSectionDataPtr(stringSection);
 
         //We have a symbol table!
         Elf32_Sym *symtab = (Elf32_Sym *)(GetSectionDataPtr(sec));
         int numSymbols = sections[sec].sh_size / sizeof(Elf32_Sym);
-        for (int sym = 0; sym < numSymbols; sym++)
-        {
+        for (int sym = 0; sym < numSymbols; sym++) {
             int size = symtab[sym].st_size;
             if (size == 0)
                 continue;
 
-            // int bind = symtab[sym].st_info >> 4;
             int type = symtab[sym].st_info & 0xF;
 
             const char *name = stringBase + symtab[sym].st_name;
@@ -144,42 +341,41 @@ bool ElfReader::LoadSymbols()
 
 namespace Loader {
 
+/// AppLoader_ELF constructor
+AppLoader_ELF::AppLoader_ELF(std::string& filename) : is_loaded(false) {
+    this->filename = filename;
+}
+
+/// AppLoader_NCCH destructor
+AppLoader_ELF::~AppLoader_ELF() {
+}
+
 /**
- * Loads an ELF file
- * @param filename String filename of ELF file
+ * Loads an NCCH file (e.g. from a CCI, or the first NCCH in a CXI)
  * @param error_string Pointer to string to put error message if an error has occurred
+ * @todo Move NCSD parsing out of here and create a separate function for loading these
  * @return True on success, otherwise false
  */
-bool Load_ELF(std::string& filename, std::string* error_string) {
-    std::string full_path = filename;
-    std::string path, file, extension;
-    SplitPath(ReplaceAll(full_path, "\\", "/"), &path, &file, &extension);
-#if EMU_PLATFORM == PLATFORM_WINDOWS
-    path = ReplaceAll(path, "/", "\\");
-#endif
-    File::IOFile f(filename, "rb");
+const ResultStatus AppLoader_ELF::Load() {
+    INFO_LOG(LOADER, "Loading ELF file %s...", filename.c_str());
 
-    if (f.IsOpen()) {
-        u32 size = (u32)f.GetSize();
-        u8* buffer = new u8[size];
-        ElfReader* elf_reader = NULL;
+    if (is_loaded)
+        return ResultStatus::ErrorAlreadyLoaded;
 
-        f.ReadBytes(buffer, size);
+    File::IOFile file(filename, "rb");
 
-        elf_reader = new ElfReader(buffer);
-        elf_reader->LoadInto(0x00100000);
+    if (file.IsOpen()) {
+        u32 size = (u32)file.GetSize();
+        std::unique_ptr<u8[]> buffer(new u8[size]);
+        file.ReadBytes(&buffer[0], size);
 
-        Kernel::LoadExec(elf_reader->GetEntryPoint());
-
-        delete[] buffer;
-        delete elf_reader;
+        ElfReader elf_reader(&buffer[0]);
+        elf_reader.LoadInto(0x00100000);
+        Kernel::LoadExec(elf_reader.GetEntryPoint());
     } else {
-        *error_string = "Unable to open ELF file!";
-        return false;
+        return ResultStatus::Error;
     }
-    f.Close();
-
-    return true;
+    return ResultStatus::Success;
 }
 
 } // namespace Loader
diff --git a/src/core/loader/elf.h b/src/core/loader/elf.h
index 24d2f91be7..3fb010113b 100644
--- a/src/core/loader/elf.h
+++ b/src/core/loader/elf.h
@@ -5,226 +5,28 @@
 #pragma once
 
 #include "common/common_types.h"
-
-// ELF Header Constants
-
-// File type
-enum ElfType {
-    ET_NONE = 0,
-    ET_REL = 1,
-    ET_EXEC = 2,
-    ET_DYN = 3,
-    ET_CORE = 4,
-    ET_LOPROC = 0xFF00,
-    ET_HIPROC = 0xFFFF,
-};
-
-// Machine/Architecture
-enum ElfMachine {
-    EM_NONE = 0,
-    EM_M32 = 1,
-    EM_SPARC = 2,
-    EM_386 = 3,
-    EM_68K = 4,
-    EM_88K = 5,
-    EM_860 = 7,
-    EM_MIPS = 8
-};
-
-// File version
-#define EV_NONE    0
-#define EV_CURRENT 1
-
-// Identification index
-#define EI_MAG0    0
-#define EI_MAG1    1
-#define EI_MAG2    2
-#define EI_MAG3    3
-#define EI_CLASS   4
-#define EI_DATA    5
-#define EI_VERSION 6
-#define EI_PAD     7
-#define EI_NIDENT 16
-
-// Magic number
-#define ELFMAG0 0x7F
-#define ELFMAG1  'E'
-#define ELFMAG2  'L'
-#define ELFMAG3  'F'
-
-// Sections constants
-
-// Section types
-#define SHT_NULL            0
-#define SHT_PROGBITS        1
-#define SHT_SYMTAB          2
-#define SHT_STRTAB          3
-#define SHT_RELA            4
-#define SHT_HASH            5
-#define SHT_DYNAMIC         6
-#define SHT_NOTE            7
-#define SHT_NOBITS          8
-#define SHT_REL             9
-#define SHT_SHLIB          10
-#define SHT_DYNSYM         11
-#define SHT_LOPROC 0x70000000
-#define SHT_HIPROC 0x7FFFFFFF
-#define SHT_LOUSER 0x80000000
-#define SHT_HIUSER 0xFFFFFFFF
-
-// Section flags
-enum ElfSectionFlags
-{
-    SHF_WRITE = 0x1,
-    SHF_ALLOC = 0x2,
-    SHF_EXECINSTR = 0x4,
-    SHF_MASKPROC = 0xF0000000,
-};
-
-// Segment types
-#define PT_NULL             0
-#define PT_LOAD             1
-#define PT_DYNAMIC          2
-#define PT_INTERP           3
-#define PT_NOTE             4
-#define PT_SHLIB            5
-#define PT_PHDR             6
-#define PT_LOPROC  0x70000000
-#define PT_HIPROC  0x7FFFFFFF
-
-typedef unsigned int  Elf32_Addr;
-typedef unsigned short Elf32_Half;
-typedef unsigned int  Elf32_Off;
-typedef signed   int  Elf32_Sword;
-typedef unsigned int  Elf32_Word;
-
-// ELF file header
-struct Elf32_Ehdr {
-    unsigned char e_ident[EI_NIDENT];
-    Elf32_Half    e_type;
-    Elf32_Half    e_machine;
-    Elf32_Word    e_version;
-    Elf32_Addr    e_entry;
-    Elf32_Off     e_phoff;
-    Elf32_Off     e_shoff;
-    Elf32_Word    e_flags;
-    Elf32_Half    e_ehsize;
-    Elf32_Half    e_phentsize;
-    Elf32_Half    e_phnum;
-    Elf32_Half    e_shentsize;
-    Elf32_Half    e_shnum;
-    Elf32_Half    e_shstrndx;
-};
-
-// Section header
-struct Elf32_Shdr {
-    Elf32_Word sh_name;
-    Elf32_Word sh_type;
-    Elf32_Word sh_flags;
-    Elf32_Addr sh_addr;
-    Elf32_Off  sh_offset;
-    Elf32_Word sh_size;
-    Elf32_Word sh_link;
-    Elf32_Word sh_info;
-    Elf32_Word sh_addralign;
-    Elf32_Word sh_entsize;
-};
-
-// Segment header
-struct Elf32_Phdr {
-    Elf32_Word p_type;
-    Elf32_Off  p_offset;
-    Elf32_Addr p_vaddr;
-    Elf32_Addr p_paddr;
-    Elf32_Word p_filesz;
-    Elf32_Word p_memsz;
-    Elf32_Word p_flags;
-    Elf32_Word p_align;
-};
-
-// Symbol table entry
-struct Elf32_Sym {
-    Elf32_Word    st_name;
-    Elf32_Addr    st_value;
-    Elf32_Word    st_size;
-    unsigned char st_info;
-    unsigned char st_other;
-    Elf32_Half    st_shndx;
-};
-
-// Relocation entries
-struct Elf32_Rel {
-    Elf32_Addr r_offset;
-    Elf32_Word r_info;
-};
-
-typedef int SectionID;
-
-class ElfReader {
-private:
-    char *base;
-    u32 *base32;
-
-    Elf32_Ehdr *header;
-    Elf32_Phdr *segments;
-    Elf32_Shdr *sections;
-
-    u32 *sectionAddrs;
-    bool bRelocate;
-    u32 entryPoint;
-
-public:
-    ElfReader(void *ptr);
-    ~ElfReader() { }
-
-    u32 Read32(int off) const { return base32[off >> 2]; }
-
-    // Quick accessors
-    ElfType GetType() const { return (ElfType)(header->e_type); }
-    ElfMachine GetMachine() const { return (ElfMachine)(header->e_machine); }
-    u32 GetEntryPoint() const { return entryPoint; }
-    u32 GetFlags() const { return (u32)(header->e_flags); }
-    bool LoadInto(u32 vaddr);
-    bool LoadSymbols();
-
-    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 != SHT_NOBITS)
-            return GetPtr(sections[section].sh_offset);
-        else
-            return nullptr;
-    }
-    bool IsCodeSection(int section) const {
-        return sections[section].sh_type == SHT_PROGBITS;
-    }
-    const u8 *GetSegmentPtr(int segment) {
-        return GetPtr(segments[segment].p_offset);
-    }
-    u32 GetSectionAddr(SectionID section) const { return sectionAddrs[section]; }
-    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() {
-        return bRelocate;
-    }
-};
+#include "core/loader/loader.h"
 
 ////////////////////////////////////////////////////////////////////////////////////////////////////
 // Loader namespace
 
 namespace Loader {
 
-/**
- * Loads an ELF file
- * @param filename String filename of ELF file
- * @param error_string Pointer to string to put error message if an error has occurred
- * @return True on success, otherwise false
- */
-bool Load_ELF(std::string& filename, std::string* error_string);
+/// Loads an ELF/AXF file
+class AppLoader_ELF : public AppLoader {
+public:
+    AppLoader_ELF(std::string& filename);
+    ~AppLoader_ELF();
+
+    /**
+     * Load the bootable file
+     * @return ResultStatus result of function
+     */
+    const ResultStatus Load();
+
+private:
+    std::string filename;
+    bool        is_loaded;
+};
 
 } // namespace Loader
diff --git a/src/core/loader/loader.cpp b/src/core/loader/loader.cpp
index 1a647d8a51..dd0863ff30 100644
--- a/src/core/loader/loader.cpp
+++ b/src/core/loader/loader.cpp
@@ -2,6 +2,8 @@
 // Licensed under GPLv2
 // Refer to the license.txt file included.
 
+#include <memory>
+
 #include "core/loader/loader.h"
 #include "core/loader/elf.h"
 #include "core/loader/ncch.h"
@@ -16,59 +18,60 @@ namespace Loader {
  * @todo (ShizZy) this function sucks... make it actually check file contents etc.
  * @return FileType of file
  */
-FileType IdentifyFile(std::string &filename) {
+const FileType IdentifyFile(const std::string &filename) {
     if (filename.size() == 0) {
         ERROR_LOG(LOADER, "invalid filename %s", filename.c_str());
-        return FILETYPE_ERROR;
+        return FileType::Error;
     }
     std::string extension = filename.size() >= 5 ? filename.substr(filename.size() - 4) : "";
 
     if (!strcasecmp(extension.c_str(), ".elf")) {
-        return FILETYPE_CTR_ELF; // TODO(bunnei): Do some filetype checking :p
+        return FileType::ELF; // TODO(bunnei): Do some filetype checking :p
     }
     else if (!strcasecmp(extension.c_str(), ".axf")) {
-        return FILETYPE_CTR_ELF; // TODO(bunnei): Do some filetype checking :p
+        return FileType::ELF; // TODO(bunnei): Do some filetype checking :p
     }
     else if (!strcasecmp(extension.c_str(), ".cxi")) {
-        return FILETYPE_CTR_CXI; // TODO(bunnei): Do some filetype checking :p
+        return FileType::CXI; // TODO(bunnei): Do some filetype checking :p
     }
     else if (!strcasecmp(extension.c_str(), ".cci")) {
-        return FILETYPE_CTR_CCI; // TODO(bunnei): Do some filetype checking :p
+        return FileType::CCI; // TODO(bunnei): Do some filetype checking :p
     }
-    return FILETYPE_UNKNOWN;
+    return FileType::Unknown;
 }
 
 /**
  * Identifies and loads a bootable file
  * @param filename String filename of bootable file
- * @param error_string Point to string to put error message if an error has occurred
- * @return True on success, otherwise false
+ * @return ResultStatus result of function
  */
-bool LoadFile(std::string &filename, std::string *error_string) {
-    INFO_LOG(LOADER, "Identifying file...");
+const ResultStatus LoadFile(std::string& filename) {
+    INFO_LOG(LOADER, "Loading file %s...", filename.c_str());
 
-    // Note that this can modify filename!
     switch (IdentifyFile(filename)) {
 
-    case FILETYPE_CTR_ELF:
-        return Loader::Load_ELF(filename, error_string);
-
-    case FILETYPE_CTR_CXI:
-    case FILETYPE_CTR_CCI:
-        return Loader::Load_NCCH(filename, error_string);
-
-    case FILETYPE_ERROR:
-        ERROR_LOG(LOADER, "Could not read file");
-        *error_string = "Error reading file";
-        break;
-
-    case FILETYPE_UNKNOWN:
-    default:
-        ERROR_LOG(LOADER, "Failed to identify file");
-        *error_string = " Failed to identify file";
-        break;
+    // Standard ELF file format...
+    case FileType::ELF: {
+        return AppLoader_ELF(filename).Load();
     }
-    return false;
+
+    // NCCH/NCSD container formats...
+    case FileType::CXI:
+    case FileType::CCI: {
+        return AppLoader_NCCH(filename).Load();
+    }
+
+    // Error occurred durring IdentifyFile...
+    case FileType::Error:
+
+    // IdentifyFile could know identify file type...
+    case FileType::Unknown:
+
+    default:
+        return ResultStatus::ErrorInvalidFormat;
+    }
+
+    return ResultStatus::Error;
 }
 
 } // namespace Loader
diff --git a/src/core/loader/loader.h b/src/core/loader/loader.h
index 979003553d..42caa29e69 100644
--- a/src/core/loader/loader.h
+++ b/src/core/loader/loader.h
@@ -4,6 +4,8 @@
 
 #pragma once
 
+#include <vector>
+
 #include "common/common.h"
 
 ////////////////////////////////////////////////////////////////////////////////////////////////////
@@ -11,16 +13,94 @@
 
 namespace Loader {
 
-enum FileType {
-    FILETYPE_ERROR,
+/// File types supported by CTR
+enum class FileType {
+    Error,
+    Unknown,
+    CCI,
+    CXI,
+    CIA,
+    ELF,
+};
 
-    FILETYPE_CTR_CCI,
-    FILETYPE_CTR_CIA,
-    FILETYPE_CTR_CXI,
-    FILETYPE_CTR_ELF,
-    FILETYPE_CTR_BIN,
+/// Return type for functions in Loader namespace
+enum class ResultStatus {
+    Success,
+    Error,
+    ErrorInvalidFormat,
+    ErrorNotImplemented,
+    ErrorNotLoaded,
+    ErrorAlreadyLoaded,
+};
 
-    FILETYPE_UNKNOWN
+/// Interface for loading an application
+class AppLoader : NonCopyable {
+public:
+    AppLoader() { }
+    virtual ~AppLoader() { }
+
+    /**
+     * Load the application
+     * @return ResultStatus result of function
+     */
+    virtual const ResultStatus Load() = 0;
+
+    /**
+     * Get the code (typically .code section) of the application
+     * @param error ResultStatus result of function
+     * @return Reference to code buffer
+     */
+    virtual const std::vector<u8>& GetCode(ResultStatus& error) const {
+        error = ResultStatus::ErrorNotImplemented;
+        return code;
+    }
+
+    /**
+     * Get the icon (typically .icon section) of the application
+     * @param error ResultStatus result of function
+     * @return Reference to icon buffer
+     */
+    virtual const std::vector<u8>& GetIcon(ResultStatus& error) const {
+        error = ResultStatus::ErrorNotImplemented;
+        return icon;
+    }
+
+    /**
+     * Get the banner (typically .banner section) of the application
+     * @param error ResultStatus result of function
+     * @return Reference to banner buffer
+     */
+    virtual const std::vector<u8>& GetBanner(ResultStatus& error) const {
+        error = ResultStatus::ErrorNotImplemented;
+        return banner;
+    }
+
+    /**
+     * Get the logo (typically .logo section) of the application
+     * @param error ResultStatus result of function
+     * @return Reference to logo buffer
+     */
+    virtual const std::vector<u8>& GetLogo(ResultStatus& error) const {
+        error = ResultStatus::ErrorNotImplemented;
+        return logo;
+    }
+
+    /**
+     * Get the RomFs archive of the application
+     * @param error ResultStatus result of function
+     * @return Reference to RomFs archive buffer
+     */
+    virtual const std::vector<u8>& GetRomFs(ResultStatus error) const {
+        error = ResultStatus::ErrorNotImplemented;
+        return romfs;
+    }
+
+protected:
+    std::vector<u8> code;   ///< ExeFS .code section
+    std::vector<u8> icon;   ///< ExeFS .icon section
+    std::vector<u8> banner; ///< ExeFS .banner section
+    std::vector<u8> logo;   ///< ExeFS .logo section
+    std::vector<u8> romfs;  ///< RomFs archive
 };
 
 /**
@@ -28,14 +108,13 @@ enum FileType {
  * @param filename String filename of bootable file
  * @return FileType of file
  */
-FileType IdentifyFile(std::string &filename);
+const FileType IdentifyFile(const std::string &filename);
 
 /**
  * Identifies and loads a bootable file
  * @param filename String filename of bootable file
- * @param error_string Point to string to put error message if an error has occurred
- * @return True on success, otherwise false
+ * @return ResultStatus result of function
  */
-bool LoadFile(std::string &filename, std::string *error_string);
+const ResultStatus LoadFile(std::string& filename);
 
 } // namespace
diff --git a/src/core/loader/ncch.cpp b/src/core/loader/ncch.cpp
index 23864d262c..765efcf655 100644
--- a/src/core/loader/ncch.cpp
+++ b/src/core/loader/ncch.cpp
@@ -2,142 +2,14 @@
 // Licensed under GPLv2
 // Refer to the license.txt file included.
 
+#include <memory>
+
 #include "common/file_util.h"
 
 #include "core/loader/ncch.h"
 #include "core/hle/kernel/kernel.h"
 #include "core/mem_map.h"
 
-////////////////////////////////////////////////////////////////////////////////////////////////////
-/// NCCH header (Note: "NCCH" appears to be a publically unknown acronym)
-
-struct NCCH_Header {
-    u8 signature[0x100];
-    char magic[4];
-    u32 content_size;
-    u8 partition_id[8];
-    u16 maker_code;
-    u16 version;
-    u8 reserved_0[4];
-    u8 program_id[8];
-    u8 temp_flag;
-    u8 reserved_1[0x2f];
-    u8 product_code[0x10];
-    u8 extended_header_hash[0x20];
-    u32 extended_header_size;
-    u8 reserved_2[4];
-    u8 flags[8];
-    u32 plain_region_offset;
-    u32 plain_region_size;
-    u8 reserved_3[8];
-    u32 exefs_offset;
-    u32 exefs_size;
-    u32 exefs_hash_region_size;
-    u8 reserved_4[4];
-    u32 romfs_offset;
-    u32 romfs_size;
-    u32 romfs_hash_region_size;
-    u8 reserved_5[4];
-    u8 exefs_super_block_hash[0x20];
-    u8 romfs_super_block_hash[0x20];
-};
-
-////////////////////////////////////////////////////////////////////////////////////////////////////
-// ExeFS (executable file system) headers
-
-typedef struct {
-    char name[8];
-    u32 offset;
-    u32 size;
-} ExeFs_SectionHeader;
-
-typedef struct {
-    ExeFs_SectionHeader section[8];
-    u8 reserved[0x80];
-    u8 hashes[8][0x20];
-} ExeFs_Header;
-
-////////////////////////////////////////////////////////////////////////////////////////////////////
-// ExHeader (executable file system header) headers
-
-struct ExHeader_SystemInfoFlags{
-    u8 reserved[5];
-    u8 flag;
-    u8 remaster_version[2];
-} exheader_systeminfoflags;
-
-struct ExHeader_CodeSegmentInfo{
-    u32 address;
-    u32 num_max_pages;
-    u32 code_size;
-} exheader_codesegmentinfo;
-
-struct ExHeader_CodeSetInfo {
-    u8 name[8];
-    ExHeader_SystemInfoFlags flags;
-    ExHeader_CodeSegmentInfo text;
-    u8 stacksize[4];
-    ExHeader_CodeSegmentInfo ro;
-    u8 reserved[4];
-    ExHeader_CodeSegmentInfo data;
-    u8 bsssize[4];
-};
-
-struct ExHeader_DependencyList{
-    u8 program_id[0x30][8];
-};
-
-struct ExHeader_SystemInfo{
-    u32 save_data_size;
-    u8 reserved[4];
-    u8 jump_id[8];
-    u8 reserved_2[0x30];
-};
-
-struct ExHeader_StorageInfo{
-    u8 ext_save_data_id[8];
-    u8 system_save_data_id[8];
-    u8 reserved[8];
-    u8 access_info[7];
-    u8 other_attributes;
-};
-
-struct ExHeader_ARM11_SystemLocalCaps{
-    u8 program_id[8];
-    u8 flags[8];
-    u8 resource_limit_descriptor[0x10][2];
-    ExHeader_StorageInfo storage_info;
-    u8 service_access_control[0x20][8];
-    u8 reserved[0x1f];
-    u8 resource_limit_category;
-};
-
-struct ExHeader_ARM11_KernelCaps{
-    u8 descriptors[28][4];
-    u8 reserved[0x10];
-};
-
-struct ExHeader_ARM9_AccessControl{
-    u8 descriptors[15];
-    u8 descversion;
-};
-
-struct ExHeader_Header{
-    ExHeader_CodeSetInfo codeset_info;
-    ExHeader_DependencyList dependency_list;
-    ExHeader_SystemInfo system_info;
-    ExHeader_ARM11_SystemLocalCaps arm11_system_local_caps;
-    ExHeader_ARM11_KernelCaps arm11_kernel_caps;
-    ExHeader_ARM9_AccessControl arm9_access_control;
-    struct {
-        u8 signature[0x100];
-        u8 ncch_public_key_modulus[0x100];
-        ExHeader_ARM11_SystemLocalCaps arm11_system_local_caps;
-        ExHeader_ARM11_KernelCaps arm11_kernel_caps;
-        ExHeader_ARM9_AccessControl arm9_access_control;
-    } access_desc;
-};
-
 ////////////////////////////////////////////////////////////////////////////////////////////////////
 // Loader namespace
 
@@ -163,11 +35,9 @@ u32 LZSS_GetDecompressedSize(u8* buffer, u32 size) {
  * @param compressed_size Size of compressed buffer
  * @param decompressed Decompressed buffer
  * @param decompressed_size Size of decompressed buffer
- * @param error_string String populated with error message on failure
  * @return True on success, otherwise false
  */
-bool LZSS_Decompress(u8* compressed, u32 compressed_size, u8* decompressed, u32 decompressed_size, 
-    std::string* error_string) {
+bool LZSS_Decompress(u8* compressed, u32 compressed_size, u8* decompressed, u32 decompressed_size) {
     u8* footer = compressed + compressed_size - 8;
     u32 buffer_top_and_bottom = *(u32*)footer;
     u32 i, j;
@@ -191,8 +61,8 @@ bool LZSS_Decompress(u8* compressed, u32 compressed_size, u8* decompressed, u32
                 break;
 
             if(control & 0x80) {
+                // Check if compression is out of bounds
                 if(index < 2) {
-                    *error_string = "Compression out of bounds";
                     return false;
                 }
                 index -= 2;
@@ -202,22 +72,22 @@ bool LZSS_Decompress(u8* compressed, u32 compressed_size, u8* decompressed, u32
                 segment_offset &= 0x0FFF;
                 segment_offset += 2;
 
+                // Check if compression is out of bounds
                 if(out < segment_size) {
-                    *error_string = "Compression out of bounds";
                     return false;
                 }
                 for(j = 0; j < segment_size; j++) {
                     u8 data;
+                    // Check if compression is out of bounds
                     if(out + segment_offset >= decompressed_size) {
-                        *error_string = "Compression out of bounds";
                         return false;
                     }
                     data  = decompressed[out + segment_offset];
                     decompressed[--out] = data;
                 }
             } else {
+                // Check if compression is out of bounds
                 if(out < 1) {
-                    *error_string = "Compression out of bounds";
                     return false;
                 }
                 decompressed[--out] = compressed[--index];
@@ -228,34 +98,96 @@ bool LZSS_Decompress(u8* compressed, u32 compressed_size, u8* decompressed, u32
     return true;
 }
 
-/**
- * Load a data buffer into memory at the specified address
- * @param addr Address to load memory into
- * @param buffer Buffer of data to load into memory
- * @param size Size of data to load into memory
- * @todo Perhaps move this code somewhere more generic?
- */
-void LoadBuffer(const u32 addr, const u8* const buffer, const int size) {
-    u32 *dst = (u32*)Memory::GetPointer(addr);
-    u32 *src = (u32*)buffer;
-    int size_aligned = (size + 3) / 4;
+////////////////////////////////////////////////////////////////////////////////////////////////////
+// AppLoader_NCCH class
 
-    for (int j = 0; j < size_aligned; j++) {
-        *dst++ = (*src++);
-    }
-    return;
+/// AppLoader_NCCH constructor
+AppLoader_NCCH::AppLoader_NCCH(std::string& filename) {
+    this->filename = filename;
+    is_loaded = false;
+    is_compressed = false;
+    entry_point = 0;
+    ncch_offset = 0;
+    exefs_offset = 0;
+}
+
+/// AppLoader_NCCH destructor
+AppLoader_NCCH::~AppLoader_NCCH() {
 }
 
+/**
+ * Loads .code section into memory for booting
+ * @return ResultStatus result of function
+ */
+const ResultStatus AppLoader_NCCH::LoadExec() const {
+    if (!is_loaded) 
+        return ResultStatus::ErrorNotLoaded;
+
+    for (std::vector<u8>::size_type i = 0; i != code.size(); i++) {
+        Memory::Write8(entry_point + i, code[i]);
+    }
+    Kernel::LoadExec(entry_point);
+    
+    return ResultStatus::Success;
+}
+
+/**
+ * Reads an application section of an NCCH file into AppLoader (e.g. .code, .logo, etc.)
+ * @param file Handle to file to read from
+ * @param name Name of section to read out of NCCH file
+ * @param buffer Buffer to read section into.
+ */
+const ResultStatus AppLoader_NCCH::LoadSection(File::IOFile& file, const char* name, 
+    std::vector<u8>& buffer) {
+    // Iterate through the ExeFs archive until we find the .code file...
+    for (int i = 0; i < kExeFs_MaxSections; i++) {
+        INFO_LOG(LOADER, "ExeFS section %d:", i);
+        INFO_LOG(LOADER, "    name:   %s", exefs_header.section[i].name);
+        INFO_LOG(LOADER, "    offset: 0x%08X", exefs_header.section[i].offset);
+        INFO_LOG(LOADER, "    size:   0x%08X", exefs_header.section[i].size);
+
+        // Load the .code section (executable code)...
+        if (strcmp((const char*)exefs_header.section[i].name, name) == 0) {
+            s64 section_offset = (exefs_header.section[i].offset + exefs_offset + 
+                sizeof(ExeFs_Header) + ncch_offset);
+            file.Seek(section_offset, 0);
+
+            // Section is compressed...
+            if (i == 0 && is_compressed) {
+                // Read compressed .code section...
+                std::unique_ptr<u8[]> temp_buffer(new u8[exefs_header.section[i].size]);
+                file.ReadBytes(&temp_buffer[0], exefs_header.section[i].size);
+
+                // Decompress .code section...
+                u32 decompressed_size = LZSS_GetDecompressedSize(&temp_buffer[0], exefs_header.section[i].size);
+                buffer.resize(decompressed_size);
+                if (!LZSS_Decompress(&temp_buffer[0], exefs_header.section[i].size, &buffer[0], 
+                    decompressed_size)) {
+                    return ResultStatus::ErrorInvalidFormat;
+                }
+            // Section is uncompressed...
+            } else {
+                buffer.resize(exefs_header.section[i].size);
+                file.ReadBytes(&buffer[0], exefs_header.section[i].size);
+            }
+            return ResultStatus::Success;
+        }
+    }
+    return ResultStatus::Error;
+} 
+
 /**
  * Loads an NCCH file (e.g. from a CCI, or the first NCCH in a CXI)
- * @param filename String filename of NCCH file
  * @param error_string Pointer to string to put error message if an error has occurred
  * @todo Move NCSD parsing out of here and create a separate function for loading these
  * @return True on success, otherwise false
  */
-bool Load_NCCH(std::string& filename, std::string* error_string) {
+const ResultStatus AppLoader_NCCH::Load() {
     INFO_LOG(LOADER, "Loading NCCH file %s...", filename.c_str());
 
+    if (is_loaded)
+        return ResultStatus::ErrorAlreadyLoaded;
+
     File::IOFile file(filename, "rb");
 
     if (file.IsOpen()) {
@@ -263,80 +195,50 @@ bool Load_NCCH(std::string& filename, std::string* error_string) {
         file.ReadBytes(&ncch_header, sizeof(NCCH_Header));
 
         // Skip NCSD header and load first NCCH (NCSD is just a container of NCCH files)...
-        int ncch_off = 0; // Offset to NCCH header, can be 0 or after NCSD header
-        if (memcmp(&ncch_header.magic, "NCSD", 4) == 0) {
+        if (0 == memcmp(&ncch_header.magic, "NCSD", 4)) {
             WARN_LOG(LOADER, "Only loading the first (bootable) NCCH within the NCSD file!");
-            ncch_off = 0x4000;
-            file.Seek(ncch_off, 0);
+            ncch_offset = 0x4000;
+            file.Seek(ncch_offset, 0);
             file.ReadBytes(&ncch_header, sizeof(NCCH_Header));
         }
+        
         // Verify we are loading the correct file type...
-        if (memcmp(&ncch_header.magic, "NCCH", 4) != 0) {
-            *error_string = "Invalid NCCH magic number (likely incorrect file type)";
-            return false;
-        }
+        if (0 != memcmp(&ncch_header.magic, "NCCH", 4))
+            return ResultStatus::ErrorInvalidFormat;
+
         // Read ExHeader
-        ExHeader_Header exheader_header;
         file.ReadBytes(&exheader_header, sizeof(ExHeader_Header));
 
-        bool is_compressed = (exheader_header.codeset_info.flags.flag & 1) == 1;
+        is_compressed = (exheader_header.codeset_info.flags.flag & 1) == 1;
+        entry_point = exheader_header.codeset_info.text.address;
 
         INFO_LOG(LOADER, "Name:            %s", exheader_header.codeset_info.name);
         INFO_LOG(LOADER, "Code compressed: %s", is_compressed ? "yes" : "no");
+        INFO_LOG(LOADER, "Entry point:     0x%08X", entry_point);
 
         // Read ExeFS
-        u32 exefs_offset = ncch_header.exefs_offset * kExeFs_BlockSize;
+        exefs_offset = ncch_header.exefs_offset * kExeFs_BlockSize;
         u32 exefs_size = ncch_header.exefs_size * kExeFs_BlockSize;
 
         INFO_LOG(LOADER, "ExeFS offset:    0x%08X", exefs_offset);
         INFO_LOG(LOADER, "ExeFS size:      0x%08X", exefs_size);
 
-        ExeFs_Header exefs_header;
-        file.Seek(exefs_offset + ncch_off, 0);
+        file.Seek(exefs_offset + ncch_offset, 0);
         file.ReadBytes(&exefs_header, sizeof(ExeFs_Header));
 
-        // Iterate through the ExeFs archive until we find the .code file...
-        for (int i = 0; i < kExeFs_MaxSections; i++) {
-            INFO_LOG(LOADER, "ExeFS section %d:", i);
-            INFO_LOG(LOADER, "    name:   %s", exefs_header.section[i].name);
-            INFO_LOG(LOADER, "    offset: 0x%08X", exefs_header.section[i].offset);
-            INFO_LOG(LOADER, "    size:   0x%08X", exefs_header.section[i].size);
+        // TODO(bunnei): Check ResultStatus here...
+        LoadSection(file, ".code", code);
+        LoadSection(file, ".icon", icon);
+        LoadSection(file, ".banner", banner);
+        LoadSection(file, ".logo", logo);
 
-            // Load the .code section (executable code)...
-            if (strcmp((char*) exefs_header.section[i].name, ".code") == 0) {
-                file.Seek(exefs_header.section[i].offset + exefs_offset + sizeof(ExeFs_Header) + 
-                    ncch_off, 0);
+        is_loaded = true; // Set state to loaded
 
-                u8* buffer = new u8[exefs_header.section[i].size];
-                file.ReadBytes(buffer, exefs_header.section[i].size);
+        LoadExec(); // Load the executable into memory for booting
 
-                // Load compressed executable...
-                if (i == 0 && is_compressed) {
-                    u32 decompressed_size = LZSS_GetDecompressedSize(buffer,
-                        exefs_header.section[i].size);
-
-                    if (!LZSS_Decompress(buffer, exefs_header.section[i].size,
-                        Memory::GetPointer(exheader_header.codeset_info.text.address),
-                        decompressed_size, error_string)) {
-                        return false;
-                    }
-                // Load uncompressed executable...
-                } else {
-                    // Load .code section into memory...
-                    LoadBuffer(exheader_header.codeset_info.text.address, buffer, 
-                        exefs_header.section[i].size);
-                }
-                delete[] buffer;
-
-                // Setup kernel emulation to boot .code section...
-                Kernel::LoadExec(exheader_header.codeset_info.text.address);
-
-                // No need to load the other files from ExeFS until we do something with them...
-                return true;
-            }
-        }
+        return ResultStatus::Success;
     }
-    return false;
+    return ResultStatus::Error;
 }
 
 } // namespace Loader
diff --git a/src/core/loader/ncch.h b/src/core/loader/ncch.h
index 778e8b4569..3aae5417c0 100644
--- a/src/core/loader/ncch.h
+++ b/src/core/loader/ncch.h
@@ -5,17 +5,184 @@
 #pragma once
 
 #include "common/common.h"
+#include "common/file_util.h"
+
+#include "core/loader/loader.h"
 
 ////////////////////////////////////////////////////////////////////////////////////////////////////
+/// NCCH header (Note: "NCCH" appears to be a publically unknown acronym)
+
+struct NCCH_Header {
+    u8 signature[0x100];
+    char magic[4];
+    u32 content_size;
+    u8 partition_id[8];
+    u16 maker_code;
+    u16 version;
+    u8 reserved_0[4];
+    u8 program_id[8];
+    u8 temp_flag;
+    u8 reserved_1[0x2f];
+    u8 product_code[0x10];
+    u8 extended_header_hash[0x20];
+    u32 extended_header_size;
+    u8 reserved_2[4];
+    u8 flags[8];
+    u32 plain_region_offset;
+    u32 plain_region_size;
+    u8 reserved_3[8];
+    u32 exefs_offset;
+    u32 exefs_size;
+    u32 exefs_hash_region_size;
+    u8 reserved_4[4];
+    u32 romfs_offset;
+    u32 romfs_size;
+    u32 romfs_hash_region_size;
+    u8 reserved_5[4];
+    u8 exefs_super_block_hash[0x20];
+    u8 romfs_super_block_hash[0x20];
+};
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+// ExeFS (executable file system) headers
+
+typedef struct {
+    char name[8];
+    u32 offset;
+    u32 size;
+} ExeFs_SectionHeader;
+
+typedef struct {
+    ExeFs_SectionHeader section[8];
+    u8 reserved[0x80];
+    u8 hashes[8][0x20];
+} ExeFs_Header;
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+// ExHeader (executable file system header) headers
+
+struct ExHeader_SystemInfoFlags{
+    u8 reserved[5];
+    u8 flag;
+    u8 remaster_version[2];
+};
+
+struct ExHeader_CodeSegmentInfo{
+    u32 address;
+    u32 num_max_pages;
+    u32 code_size;
+};
+
+struct ExHeader_CodeSetInfo {
+    u8 name[8];
+    ExHeader_SystemInfoFlags flags;
+    ExHeader_CodeSegmentInfo text;
+    u8 stacksize[4];
+    ExHeader_CodeSegmentInfo ro;
+    u8 reserved[4];
+    ExHeader_CodeSegmentInfo data;
+    u8 bsssize[4];
+};
+
+struct ExHeader_DependencyList{
+    u8 program_id[0x30][8];
+};
+
+struct ExHeader_SystemInfo{
+    u32 save_data_size;
+    u8 reserved[4];
+    u8 jump_id[8];
+    u8 reserved_2[0x30];
+};
+
+struct ExHeader_StorageInfo{
+    u8 ext_save_data_id[8];
+    u8 system_save_data_id[8];
+    u8 reserved[8];
+    u8 access_info[7];
+    u8 other_attributes;
+};
+
+struct ExHeader_ARM11_SystemLocalCaps{
+    u8 program_id[8];
+    u8 flags[8];
+    u8 resource_limit_descriptor[0x10][2];
+    ExHeader_StorageInfo storage_info;
+    u8 service_access_control[0x20][8];
+    u8 reserved[0x1f];
+    u8 resource_limit_category;
+};
+
+struct ExHeader_ARM11_KernelCaps{
+    u8 descriptors[28][4];
+    u8 reserved[0x10];
+};
+
+struct ExHeader_ARM9_AccessControl{
+    u8 descriptors[15];
+    u8 descversion;
+};
+
+struct ExHeader_Header{
+    ExHeader_CodeSetInfo codeset_info;
+    ExHeader_DependencyList dependency_list;
+    ExHeader_SystemInfo system_info;
+    ExHeader_ARM11_SystemLocalCaps arm11_system_local_caps;
+    ExHeader_ARM11_KernelCaps arm11_kernel_caps;
+    ExHeader_ARM9_AccessControl arm9_access_control;
+    struct {
+        u8 signature[0x100];
+        u8 ncch_public_key_modulus[0x100];
+        ExHeader_ARM11_SystemLocalCaps arm11_system_local_caps;
+        ExHeader_ARM11_KernelCaps arm11_kernel_caps;
+        ExHeader_ARM9_AccessControl arm9_access_control;
+    } access_desc;
+};
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+// Loader namespace
 
 namespace Loader {
 
-/**
- * Loads an NCCH file (e.g. from a CCI or CXI)
- * @param filename String filename of NCCH file
- * @param error_string Pointer to string to put error message if an error has occurred
- * @return True on success, otherwise false
- */
-bool Load_NCCH(std::string& filename, std::string* error_string);
+/// Loads an NCCH file (e.g. from a CCI, or the first NCCH in a CXI)
+class AppLoader_NCCH : public AppLoader {
+public:
+    AppLoader_NCCH(std::string& filename);
+    ~AppLoader_NCCH();
+
+    /**
+     * Load the application
+     * @return ResultStatus result of function
+     */
+    const ResultStatus Load();
+
+private:
+
+    /**
+     * Reads an application section of an NCCH file into AppLoader (e.g. .code, .logo, etc.)
+     * @param file Handle to file to read from
+     * @param name Name of section to read out of NCCH file
+     * @param buffer Buffer to read section into.
+     */
+    const ResultStatus LoadSection(File::IOFile& file, const char* name, 
+        std::vector<u8>& buffer);
+
+    /**
+     * Loads .code section into memory for booting
+     * @return ResultStatus result of function
+     */
+    const ResultStatus LoadExec() const;
+
+    std::string     filename;
+    bool            is_loaded;
+    bool            is_compressed;
+    u32             entry_point;
+
+    u32             ncch_offset; // Offset to NCCH header, can be 0 or after NCSD header
+    u32             exefs_offset;
+    
+    ExeFs_Header    exefs_header;
+    ExHeader_Header exheader_header;
+};
 
 } // namespace Loader