citra-emu
/
citra-nightly
Archived
1
0
Fork 0
Code

ncch_container: Get rid of pointer casts in LZSS_GetDecompressedSize() and LZSS_Decompress() 

These kinds of casts invoke undefined behavior, due to both the aliasing
rule, and from an alignment point-of-view. Use the way that's guaranteed
to always work instead.
This commit is contained in:
Lioncash 2018-03-28 19:55:24 -04:00
parent 74465389f3
commit 3af976e41e
1 changed files with 6 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
src/core/file_sys/ncch_container.cpp
View File

@ -26,7 +26,8 @@ static const int kBlockSize = 0x200; ///< Size of ExeFS blocks (in bytes)
* @return Size of decompressed buffer * @return Size of decompressed buffer
*/ */
static u32 LZSS_GetDecompressedSize(const u8* buffer, u32 size) { static u32 LZSS_GetDecompressedSize(const u8* buffer, u32 size) {
u32 offset_size = *(u32*)(buffer + size - 4); u32 offset_size;
std::memcpy(&offset_size, buffer + size - sizeof(u32), sizeof(u32));
return offset_size + size; return offset_size + size;
} }
@ -41,7 +42,10 @@ static u32 LZSS_GetDecompressedSize(const u8* buffer, u32 size) {
static bool LZSS_Decompress(const u8* compressed, u32 compressed_size, u8* decompressed, static bool LZSS_Decompress(const u8* compressed, u32 compressed_size, u8* decompressed,
u32 decompressed_size) { u32 decompressed_size) {
const u8* footer = compressed + compressed_size - 8; const u8* footer = compressed + compressed_size - 8;
u32 buffer_top_and_bottom = *reinterpret_cast<const u32*>(footer);
u32 buffer_top_and_bottom;
std::memcpy(&buffer_top_and_bottom, footer, sizeof(u32));
u32 out = decompressed_size; u32 out = decompressed_size;
u32 index = compressed_size - ((buffer_top_and_bottom >> 24) & 0xFF); u32 index = compressed_size - ((buffer_top_and_bottom >> 24) & 0xFF);
u32 stop_index = compressed_size - (buffer_top_and_bottom & 0xFFFFFF); u32 stop_index = compressed_size - (buffer_top_and_bottom & 0xFFFFFF);