Loader: Clean up the NCCH AppLoader.

This commit is contained in:
Emmanuel Gil Peyrot 2015-01-07 01:01:19 +00:00
parent 2c24e539a2
commit 08aaa33500

View file

@ -13,8 +13,8 @@
namespace Loader {
static const int kMaxSections = 8; ///< Maximum number of sections (files) in an ExeFs
static const int kBlockSize = 0x200; ///< Size of ExeFS blocks (in bytes)
static const int kMaxSections = 8; ///< Maximum number of sections (files) in an ExeFs
static const int kBlockSize = 0x200; ///< Size of ExeFS blocks (in bytes)
/**
* Get the decompressed size of an LZSS compressed ExeFS file
@ -22,7 +22,7 @@ static const int kBlockSize = 0x200; ///< Size of ExeFS blocks (in bytes)
* @param size Size of compressed buffer
* @return Size of decompressed buffer
*/
static u32 LZSS_GetDecompressedSize(u8* buffer, u32 size) {
static u32 LZSS_GetDecompressedSize(const u8* buffer, u32 size) {
u32 offset_size = *(u32*)(buffer + size - 4);
return offset_size + size;
}
@ -35,9 +35,9 @@ static u32 LZSS_GetDecompressedSize(u8* buffer, u32 size) {
* @param decompressed_size Size of decompressed buffer
* @return True on success, otherwise false
*/
static 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;
static bool LZSS_Decompress(const u8* compressed, u32 compressed_size, u8* decompressed, u32 decompressed_size) {
const u8* footer = compressed + compressed_size - 8;
u32 buffer_top_and_bottom = *reinterpret_cast<const u32*>(footer);
u32 out = decompressed_size;
u32 index = compressed_size - ((buffer_top_and_bottom >> 24) & 0xFF);
u32 stop_index = compressed_size - (buffer_top_and_bottom & 0xFFFFFF);
@ -45,22 +45,21 @@ static bool LZSS_Decompress(u8* compressed, u32 compressed_size, u8* decompresse
memset(decompressed, 0, decompressed_size);
memcpy(decompressed, compressed, compressed_size);
while(index > stop_index) {
while (index > stop_index) {
u8 control = compressed[--index];
for(u32 i = 0; i < 8; i++) {
if(index <= stop_index)
for (unsigned i = 0; i < 8; i++) {
if (index <= stop_index)
break;
if(index <= 0)
if (index <= 0)
break;
if(out <= 0)
if (out <= 0)
break;
if(control & 0x80) {
if (control & 0x80) {
// Check if compression is out of bounds
if(index < 2) {
if (index < 2)
return false;
}
index -= 2;
u32 segment_offset = compressed[index] | (compressed[index + 1] << 8);
@ -69,23 +68,21 @@ static bool LZSS_Decompress(u8* compressed, u32 compressed_size, u8* decompresse
segment_offset += 2;
// Check if compression is out of bounds
if(out < segment_size) {
if (out < segment_size)
return false;
}
for(u32 j = 0; j < segment_size; j++) {
// Check if compression is out of bounds
if(out + segment_offset >= decompressed_size) {
return false;
}
u8 data = decompressed[out + segment_offset];
for (unsigned j = 0; j < segment_size; j++) {
// Check if compression is out of bounds
if (out + segment_offset >= decompressed_size)
return false;
u8 data = decompressed[out + segment_offset];
decompressed[--out] = data;
}
} else {
// Check if compression is out of bounds
if(out < 1) {
if (out < 1)
return false;
}
decompressed[--out] = compressed[--index];
}
control <<= 1;
@ -126,46 +123,44 @@ ResultStatus AppLoader_NCCH::LoadExec() const {
}
ResultStatus AppLoader_NCCH::LoadSectionExeFS(const char* name, std::vector<u8>& buffer) const {
// Iterate through the ExeFs archive until we find the .code file...
if (!file->IsOpen())
return ResultStatus::Error;
LOG_DEBUG(Loader, "%d sections:", kMaxSections);
for (int i = 0; i < kMaxSections; i++) {
// Load the specified section...
if (strcmp((const char*)exefs_header.section[i].name, name) == 0) {
LOG_DEBUG(Loader, "%d - offset: 0x%08X, size: 0x%08X, name: %s", i,
exefs_header.section[i].offset, exefs_header.section[i].size,
exefs_header.section[i].name);
// Iterate through the ExeFs archive until we find the .code file...
for (unsigned section_number = 0; section_number < kMaxSections; section_number++) {
const auto& section = exefs_header.section[section_number];
s64 section_offset = (exefs_header.section[i].offset + exefs_offset +
sizeof(ExeFs_Header)+ncch_offset);
// Load the specified section...
if (strcmp(section.name, name) == 0) {
LOG_DEBUG(Loader, "%d - offset: 0x%08X, size: 0x%08X, name: %s", section_number,
section.offset, section.size, section.name);
s64 section_offset = (section.offset + exefs_offset + sizeof(ExeFs_Header) + ncch_offset);
file->Seek(section_offset, SEEK_SET);
// Section is compressed...
if (i == 0 && is_compressed) {
// Read compressed .code section...
if (is_compressed) {
// Section is compressed, read compressed .code section...
std::unique_ptr<u8[]> temp_buffer;
try {
temp_buffer.reset(new u8[exefs_header.section[i].size]);
temp_buffer.reset(new u8[section.size]);
} catch (std::bad_alloc&) {
return ResultStatus::ErrorMemoryAllocationFailed;
}
file->ReadBytes(&temp_buffer[0], exefs_header.section[i].size);
if (file->ReadBytes(&temp_buffer[0], section.size) != section.size)
return ResultStatus::Error;
// Decompress .code section...
u32 decompressed_size = LZSS_GetDecompressedSize(&temp_buffer[0],
exefs_header.section[i].size);
u32 decompressed_size = LZSS_GetDecompressedSize(&temp_buffer[0], section.size);
buffer.resize(decompressed_size);
if (!LZSS_Decompress(&temp_buffer[0], exefs_header.section[i].size, &buffer[0],
decompressed_size)) {
if (!LZSS_Decompress(&temp_buffer[0], section.size, &buffer[0], decompressed_size))
return ResultStatus::ErrorInvalidFormat;
}
} else {
// Section is uncompressed...
}
else {
buffer.resize(exefs_header.section[i].size);
file->ReadBytes(&buffer[0], exefs_header.section[i].size);
buffer.resize(section.size);
if (file->ReadBytes(&buffer[0], section.size) != section.size)
return ResultStatus::Error;
}
return ResultStatus::Success;
}
@ -183,7 +178,8 @@ ResultStatus AppLoader_NCCH::Load() {
// Reset read pointer in case this file has been read before.
file->Seek(0, SEEK_SET);
file->ReadBytes(&ncch_header, sizeof(NCCH_Header));
if (file->ReadBytes(&ncch_header, sizeof(NCCH_Header)) != sizeof(NCCH_Header))
return ResultStatus::Error;
// Skip NCSD header and load first NCCH (NCSD is just a container of NCCH files)...
if (MakeMagic('N', 'C', 'S', 'D') == ncch_header.magic) {
@ -199,7 +195,8 @@ ResultStatus AppLoader_NCCH::Load() {
// Read ExHeader...
file->ReadBytes(&exheader_header, sizeof(ExHeader_Header));
if (file->ReadBytes(&exheader_header, sizeof(ExHeader_Header)) != sizeof(ExHeader_Header))
return ResultStatus::Error;
is_compressed = (exheader_header.codeset_info.flags.flag & 1) == 1;
entry_point = exheader_header.codeset_info.text.address;
@ -217,13 +214,12 @@ ResultStatus AppLoader_NCCH::Load() {
LOG_DEBUG(Loader, "ExeFS size: 0x%08X", exefs_size);
file->Seek(exefs_offset + ncch_offset, SEEK_SET);
file->ReadBytes(&exefs_header, sizeof(ExeFs_Header));
LoadExec(); // Load the executable into memory for booting
if (file->ReadBytes(&exefs_header, sizeof(ExeFs_Header)) != sizeof(ExeFs_Header))
return ResultStatus::Error;
is_loaded = true; // Set state to loaded
return ResultStatus::Success;
return LoadExec(); // Load the executable into memory for booting
}
ResultStatus AppLoader_NCCH::ReadCode(std::vector<u8>& buffer) const {
@ -257,7 +253,8 @@ ResultStatus AppLoader_NCCH::ReadRomFS(std::vector<u8>& buffer) const {
buffer.resize(romfs_size);
file->Seek(romfs_offset, SEEK_SET);
file->ReadBytes(&buffer[0], romfs_size);
if (file->ReadBytes(&buffer[0], romfs_size) != romfs_size)
return ResultStatus::Error;
return ResultStatus::Success;
}