From 08aaa3350066b5d506368d18dddba3f829c85b7a Mon Sep 17 00:00:00 2001
From: Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>
Date: Wed, 7 Jan 2015 01:01:19 +0000
Subject: [PATCH] Loader: Clean up the NCCH AppLoader.
---
src/core/loader/ncch.cpp | 105 +++++++++++++++++++--------------------
1 file changed, 51 insertions(+), 54 deletions(-)
diff --git a/src/core/loader/ncch.cpp b/src/core/loader/ncch.cpp
index d6eb549b7..aaaa4d650 100644
--- a/src/core/loader/ncch.cpp
+++ b/src/core/loader/ncch.cpp
@@ -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;
}