[core] Support block-compressed NSZ and XCZ

This commit is contained in:
PavelBARABANOV
2026-10-18 13:14:14 +03:00
parent e0d47f2790
commit 17091b59f1
14 changed files with 415 additions and 10 deletions
@@ -100,7 +100,7 @@ class Game(
companion object {
val extensions: Set<String> = HashSet(
listOf("xci", "nsp", "nca", "nro")
listOf("xci", "nsp", "nca", "nro", "nsz", "xcz")
)
}
}
@@ -109,7 +109,7 @@ object GameHelper {
// File extensions considered as external content, buuut should
// be done better imo.
private val externalContentExtensions = setOf("nsp", "xci")
private val externalContentExtensions = setOf("nsp", "xci", "nsz", "xcz")
private fun scanContentContainersRecursive(
files: Array<MinimalDocumentFile>,
+9
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@@ -1,3 +1,6 @@
// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
// SPDX-License-Identifier: GPL-3.0-or-later
// SPDX-FileCopyrightText: Copyright 2019 yuzu Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later
@@ -46,4 +49,10 @@ std::vector<u8> DecompressDataZSTD(std::span<const u8> compressed) {
return decompressed;
}
std::size_t DecompressDataZSTD(std::span<const u8> compressed, std::span<u8> output) {
const std::size_t result =
ZSTD_decompress(output.data(), output.size(), compressed.data(), compressed.size());
return ZSTD_isError(result) ? 0 : result;
}
} // namespace Common::Compression
+14
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@@ -1,3 +1,6 @@
// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
// SPDX-License-Identifier: GPL-3.0-or-later
// SPDX-FileCopyrightText: Copyright 2019 yuzu Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later
@@ -42,4 +45,15 @@ namespace Common::Compression {
*/
[[nodiscard]] std::vector<u8> DecompressDataZSTD(std::span<const u8> compressed);
/**
* Decompresses a single Zstandard frame into a caller-provided buffer of known size.
*
* @param compressed the compressed source memory region.
* @param output the destination buffer. Its size is the maximum number of bytes to write.
*
* @return the number of bytes written, or 0 if the frame is invalid or doesn't fit. An empty
* frame also returns 0.
*/
[[nodiscard]] std::size_t DecompressDataZSTD(std::span<const u8> compressed, std::span<u8> output);
} // namespace Common::Compression
+2
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@@ -122,6 +122,8 @@ add_library(core STATIC
file_sys/kernel_executable.h
file_sys/nca_metadata.cpp
file_sys/nca_metadata.h
file_sys/ncz_decompressor.cpp
file_sys/ncz_decompressor.h
file_sys/partition_filesystem.cpp
file_sys/partition_filesystem.h
file_sys/patch_manager.cpp
+279
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@@ -0,0 +1,279 @@
// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
// SPDX-License-Identifier: GPL-3.0-or-later
#include <algorithm>
#include <array>
#include <cstring>
#include <memory>
#include <mutex>
#include <optional>
#include <span>
#include <string>
#include <vector>
#include "common/common_types.h"
#include "common/logging.h"
#include "common/zstd_compression.h"
#include "core/crypto/aes_util.h"
#include "core/crypto/key_manager.h"
#include "core/file_sys/ncz_decompressor.h"
#include "core/file_sys/vfs/vfs.h"
namespace Core::Crypto {
namespace {
constexpr u64 HeaderSize = 0x4000;
constexpr std::size_t SectionWire = 0x40;
constexpr std::size_t BlockFixed = 0x18;
constexpr std::array<u8, 8> SectionsMagic{'N', 'C', 'Z', 'S', 'E', 'C', 'T', 'N'};
constexpr std::array<u8, 8> BlockMagic{'N', 'C', 'Z', 'B', 'L', 'O', 'C', 'K'};
struct Section {
s64 offset, size;
u64 crypto_type;
Key128 key, counter;
bool Ctr() const { return crypto_type == 3 || crypto_type == 4; }
};
struct BlockHeader {
u32 exponent;
u64 decompressed_size;
std::vector<u32> sizes;
};
u64 Le(const u8* p, std::size_t n) {
u64 v = 0;
for (std::size_t i = n; i-- > 0;) v = (v << 8) | p[i];
return v;
}
// Mirrors nsz AESCTR.seek(): upper 8 bytes = stored counter, lower 8 = absolute NCA offset / 16.
void SetIv(Key128& iv, const Key128& base, u64 off) {
iv = base;
u64 blk = off >> 4;
for (std::size_t i = 0; i < 8; ++i) { iv[15 - i] = static_cast<u8>(blk & 0xFF); blk >>= 8; }
}
// Parse header + section table + optional block header. Returns payload_start.
std::optional<std::pair<std::vector<Section>, std::optional<BlockHeader>>> ParseHeader(
const FileSys::VirtualFile& f, u64& payload_start) {
const u64 fsize = f->GetSize();
if (fsize < HeaderSize + 16) return std::nullopt;
const auto head = f->ReadBytes(16, HeaderSize);
if (head.size() != 16 || !std::equal(head.begin(), head.begin() + 8, SectionsMagic.begin()))
return std::nullopt;
const u64 count = Le(head.data() + 8, 8);
if (count == 0 || count > 64 || count * SectionWire > fsize - HeaderSize - 16)
return std::nullopt;
const auto table = f->ReadBytes(count * SectionWire, HeaderSize + 16);
if (table.size() != count * SectionWire) return std::nullopt;
std::vector<Section> sections;
sections.reserve(count + 1);
for (u64 i = 0; i < count; ++i) {
const u8* e = table.data() + i * SectionWire;
Section s{};
s.offset = static_cast<s64>(Le(e, 8));
s.size = static_cast<s64>(Le(e + 8, 8));
s.crypto_type = Le(e + 16, 8);
std::memcpy(s.key.data(), e + 32, 16);
std::memcpy(s.counter.data(), e + 48, 16);
sections.push_back(s);
}
const u64 block_start = HeaderSize + 16 + count * SectionWire;
const auto fixed = f->ReadBytes(BlockFixed, block_start);
std::optional<BlockHeader> bh;
if (fixed.size() == BlockFixed &&
std::equal(fixed.begin(), fixed.begin() + 8, BlockMagic.begin())) {
BlockHeader b{};
b.exponent = fixed[11];
const s32 n = static_cast<s32>(Le(fixed.data() + 12, 4));
if (n <= 0) return std::nullopt;
b.decompressed_size = Le(fixed.data() + 16, 8);
const auto sizes = f->ReadBytes(static_cast<u64>(n) * 4, block_start + BlockFixed);
if (sizes.size() != static_cast<u64>(n) * 4) return std::nullopt;
b.sizes.resize(n);
for (s32 i = 0; i < n; ++i) b.sizes[i] = static_cast<u32>(Le(sizes.data() + i * 4, 4));
payload_start = block_start + BlockFixed + static_cast<u64>(n) * 4;
bh = std::move(b);
} else {
payload_start = block_start;
}
if (!sections.empty() && sections[0].offset > static_cast<s64>(HeaderSize)) {
Section fake{};
fake.offset = static_cast<s64>(HeaderSize);
fake.size = sections[0].offset - static_cast<s64>(HeaderSize);
sections.insert(sections.begin(), fake);
}
return std::make_pair(std::move(sections), std::move(bh));
}
// Sequential reader over independently-compressed blocks, one block cached (like nsz_rs).
class BlockReader {
public:
BlockReader(FileSys::VirtualFile f, const BlockHeader& bh, u64 payload_start)
: source{std::move(f)}, block_size{1ULL << bh.exponent}, sizes{bh.sizes},
decompressed_size{bh.decompressed_size} {
if (bh.exponent < 14 || bh.exponent > 32 || sizes.empty())
throw std::runtime_error("bad NCZBLOCK header");
u64 off = payload_start;
offsets.reserve(sizes.size());
for (u32 s : sizes) { offsets.push_back(off); off += s; }
}
// Fills `out` from `position`; returns bytes written.
std::size_t ReadAt(u64 position, std::span<u8> out) {
std::size_t done = 0;
while (done < out.size() && position < decompressed_size) {
const u64 id = position / block_size;
if (id >= sizes.size()) break;
if (cache_id != id && !Load(id)) break;
const u64 in = position - id * block_size;
const std::size_t n = static_cast<std::size_t>(
std::min<u64>(out.size() - done, cache.size() - in));
std::memcpy(out.data() + done, cache.data() + in, n);
done += n;
position += n;
}
return done;
}
private:
bool Load(u64 id) {
u64 want = block_size;
if (id + 1 == sizes.size()) {
const u64 rem = decompressed_size % block_size;
if (rem > 0) want = rem; // avoid the 0-size bug from the original nsz
}
try { cache.resize(static_cast<std::size_t>(want)); }
catch (const std::bad_alloc&) { return false; }
const u32 csize = sizes[id];
if (csize < want) {
const auto comp = source->ReadBytes(csize, offsets[id]);
if (comp.size() != csize ||
Common::Compression::DecompressDataZSTD(comp, cache) != want) return false;
} else if (source->Read(cache.data(), cache.size(), offsets[id]) != cache.size()) {
return false;
}
cache_id = id;
return true;
}
FileSys::VirtualFile source;
u64 block_size;
std::vector<u64> offsets;
std::vector<u32> sizes;
u64 decompressed_size;
u64 cache_id = ~0ULL;
std::vector<u8> cache;
};
class BlockNczFile final : public FileSys::VfsFile {
public:
BlockNczFile(std::string name_, std::vector<u8> hdr_, std::vector<Section> sections_,
std::unique_ptr<BlockReader> body_)
: name{std::move(name_)}, hdr{std::move(hdr_)}, sections{std::move(sections_)},
body{std::move(body_)} {
nca_size = HeaderSize;
for (const auto& s : sections)
nca_size = std::max<u64>(nca_size, static_cast<u64>(s.offset + s.size));
ciphers.reserve(sections.size());
for (const auto& s : sections)
ciphers.push_back(s.Ctr() ? std::make_unique<AESCipher<Key128>>(s.key, Mode::CTR)
: nullptr);
}
std::string GetName() const override { return name; }
std::size_t GetSize() const override { return static_cast<std::size_t>(nca_size); }
bool Resize(std::size_t) override { return false; }
FileSys::VirtualDir GetContainingDirectory() const override { return nullptr; }
bool IsWritable() const override { return false; }
bool IsReadable() const override { return true; }
std::size_t Read(u8* data, std::size_t len, std::size_t off) const override {
if (off >= nca_size) return 0;
len = static_cast<std::size_t>(std::min<u64>(len, nca_size - off));
const u64 end = off + len;
u64 pos = off;
if (pos < HeaderSize) {
const u64 n = std::min<u64>(end, HeaderSize) - pos;
std::memcpy(data, hdr.data() + pos, static_cast<std::size_t>(n));
pos += n;
}
std::scoped_lock lock{mutex};
for (std::size_t i = 0; i < sections.size() && pos < end; ++i) {
const auto& s = sections[i];
const u64 begin = std::max<u64>(static_cast<u64>(s.offset), HeaderSize);
const u64 stop = std::max<u64>(static_cast<u64>(s.offset + s.size), begin);
if (stop <= pos) continue;
if (pos < begin) {
const u64 g = std::min(end, begin);
std::memset(data + (pos - off), 0, static_cast<std::size_t>(g - pos));
pos = g;
if (pos >= end) break;
}
const u64 pe = std::min(end, stop);
const std::span<u8> piece(data + (pos - off), static_cast<std::size_t>(pe - pos));
if (body->ReadAt(pos - HeaderSize, piece) != piece.size())
return static_cast<std::size_t>(pos - off);
if (ciphers[i]) {
Key128 iv{};
SetIv(iv, s.counter, pos);
ciphers[i]->SetIV(iv);
ciphers[i]->Transcode(piece.data(), piece.size(), piece.data(), Op::Encrypt);
}
pos = pe;
}
return len;
}
std::size_t Write(const u8*, std::size_t, std::size_t) override { return 0; }
bool Rename(std::string_view) override { return false; }
private:
const std::string name;
const std::vector<u8> hdr;
const std::vector<Section> sections;
const std::unique_ptr<BlockReader> body;
std::vector<std::unique_ptr<AESCipher<Key128>>> ciphers;
mutable std::mutex mutex;
u64 nca_size{};
};
} // Anonymous namespace
bool IsBlockCompressedNCZ(const FileSys::VirtualFile& f) {
if (!f) return false;
u64 ps = 0;
const auto p = ParseHeader(f, ps);
return p && p->second.has_value();
}
FileSys::VirtualFile DecompressNCZ(const FileSys::VirtualFile& f, std::string_view name) {
if (!f) return nullptr;
u64 ps = 0;
auto parsed = ParseHeader(f, ps);
if (!parsed) return nullptr;
auto& [sections, block] = *parsed;
if (!block) {
LOG_ERROR(Crypto, "Solid NCZ is not supported (only NCZBLOCK / nsz -B)");
return nullptr;
}
auto hdr = f->ReadBytes(HeaderSize, 0);
if (hdr.size() != HeaderSize) return nullptr;
std::unique_ptr<BlockReader> body;
try { body = std::make_unique<BlockReader>(f, *block, ps); }
catch (const std::exception& e) {
LOG_ERROR(Crypto, "Failed to open NCZBLOCK: {}", e.what());
return nullptr;
}
return std::make_shared<BlockNczFile>(std::string{name}, std::move(hdr),
std::move(sections), std::move(body));
}
} // namespace Core::Crypto
+31
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@@ -0,0 +1,31 @@
// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
// SPDX-License-Identifier: GPL-3.0-or-later
#pragma once
#include <string_view>
#include "core/file_sys/vfs/vfs_types.h"
namespace Core::Crypto {
/**
* Opens an NCZBLOCK-compressed NCA (nsz -B / .xcz block format) as a VirtualFile backed by
* on-demand block decoding. Nothing is written to disk; each read decodes only the blocks it
* covers and re-encrypts CTR sections. Solid NCZ is not supported.
*
* @param ncz_file The raw NCZ payload (e.g. "<id>.ncz" entry from an NSZ/XCZ PFS0).
* @param output_name Name to give the returned VirtualFile (e.g. "<id>.nca").
*
* @return a VirtualFile for the NCA, or nullptr if the NCZ is malformed or not NCZBLOCK.
*/
[[nodiscard]] FileSys::VirtualFile DecompressNCZ(const FileSys::VirtualFile& ncz_file,
std::string_view output_name);
/**
* Returns true if the given file is an NCZ payload in block-compressed (NCZBLOCK) form,
* i.e. one that DecompressNCZ() can open. Solid NCZ returns false.
*/
[[nodiscard]] bool IsBlockCompressedNCZ(const FileSys::VirtualFile& ncz_file);
} // namespace Core::Crypto
+37
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@@ -21,6 +21,7 @@
#include "core/file_sys/content_archive.h"
#include "core/file_sys/control_metadata.h"
#include "core/file_sys/nca_metadata.h"
#include "core/file_sys/ncz_decompressor.h"
#include "core/file_sys/registered_cache.h"
#include "core/file_sys/romfs.h"
#include "core/file_sys/submission_package.h"
@@ -158,6 +159,25 @@ static std::shared_ptr<NSP> OpenContainerAsNsp(const VirtualFile& file, Loader::
return nullptr;
}
// Checks that every .ncz entry in the container is NCZBLOCK. Solid NCZ has no random access,
// and the whole point of this build is to reject it at scan time so such files never appear
// in the game list. Containers without any .ncz (plain NSP/XCI) pass through.
static bool ContainerIsFullyBlockCompressed(const std::shared_ptr<NSP>& nsp) {
if (!nsp) {
return false;
}
for (const auto& entry : nsp->GetFiles()) {
const auto name = entry->GetName();
if (name.size() < 4 || name.substr(name.size() - 4) != ".ncz") {
continue;
}
if (!Core::Crypto::IsBlockCompressedNCZ(entry)) {
return false; // solid NCZ -> reject the whole container
}
}
return true; // no .ncz at all, or all block-compressed
}
template <typename Callback>
bool ForEachContainerEntry(const std::shared_ptr<NSP>& nsp, bool only_content,
std::optional<u64> base_program_id, Callback&& on_entry) {
@@ -1273,6 +1293,12 @@ bool ManualContentProvider::AddEntriesFromContainer(VirtualFile file, bool only_
return false;
}
// Reject solid NCZ (.nsz without -B): only block-compressed NCZ is supported.
if (!ContainerIsFullyBlockCompressed(nsp)) {
LOG_DEBUG(Service_FS, "Skipping solid-compressed container: {}", file->GetName());
return false;
}
return ForEachContainerEntry(
nsp, only_content, base_program_id,
[this](TitleType title_type, ContentRecordType content_type, u64 title_id,
@@ -1434,6 +1460,12 @@ void ExternalContentProvider::ProcessNSP(const VirtualFile& file) {
return;
}
// Reject solid NCZ (.nsz without -B): Eden only supports block-compressed NCZ.
if (!ContainerIsFullyBlockCompressed(nsp)) {
LOG_DEBUG(Service_FS, "Skipping solid-compressed container: {}", file->GetName());
return;
}
LOG_DEBUG(Service_FS, "Processing NSP file: {}", file->GetName());
AddExternalEntriesFromContainer(nsp, entries, versions, multi_version_entries);
}
@@ -1444,6 +1476,11 @@ void ExternalContentProvider::ProcessXCI(const VirtualFile& file) {
return;
}
if (!ContainerIsFullyBlockCompressed(nsp)) {
LOG_DEBUG(Service_FS, "Skipping solid-compressed container: {}", file->GetName());
return;
}
AddExternalEntriesFromContainer(nsp, entries, versions, multi_version_entries);
}
+13
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@@ -15,6 +15,7 @@
#include "core/file_sys/common_funcs.h"
#include "core/file_sys/content_archive.h"
#include "core/file_sys/nca_metadata.h"
#include "core/file_sys/ncz_decompressor.h"
#include "core/file_sys/partition_filesystem.h"
#include "core/file_sys/program_metadata.h"
#include "core/file_sys/submission_package.h"
@@ -246,6 +247,18 @@ void NSP::ReadNCAs(const std::vector<VirtualFile>& files) {
const auto id_string = Common::HexToString(rec.nca_id, false);
auto next_file = pfs->GetFile(fmt::format("{}.nca", id_string));
if (next_file == nullptr) {
auto ncz_file = pfs->GetFile(fmt::format("{}.ncz", id_string));
if (ncz_file != nullptr) {
next_file = Core::Crypto::DecompressNCZ(ncz_file, fmt::format("{}.nca", id_string));
if (next_file == nullptr) {
LOG_WARNING(Service_FS, "Skipping unsupported or corrupt NCZ content {}.ncz",
id_string);
continue;
}
}
}
if (next_file == nullptr) {
if (rec.type != ContentRecordType::DeltaFragment) {
LOG_WARNING(Service_FS,
+14 -3
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@@ -82,12 +82,12 @@ std::shared_ptr<FileSys::NSP> OpenContainerAsNsp(FileSys::VirtualFile file, File
return nullptr;
}
if (type == FileType::NSP) {
if (type == FileType::NSP || type == FileType::NSZ) {
auto nsp = std::make_shared<FileSys::NSP>(file, program_id, program_index);
return nsp->GetStatus() == ResultStatus::Success ? nsp : nullptr;
}
if (type == FileType::XCI) {
if (type == FileType::XCI || type == FileType::XCZ) {
FileSys::XCI xci{file, program_id, program_index};
if (xci.GetStatus() != ResultStatus::Success) {
return nullptr;
@@ -144,7 +144,8 @@ FileType IdentifyFile(FileSys::VirtualFile file) {
}
bool IsContainerType(FileType type) {
return type == FileType::NSP || type == FileType::XCI;
return type == FileType::NSP || type == FileType::NSZ || type == FileType::XCI ||
type == FileType::XCZ;
}
bool IsBootableGameContainer(FileSys::VirtualFile file, FileType type, u64 program_id,
@@ -180,8 +181,12 @@ FileType GuessFromFilename(const std::string& name) {
return FileType::NCA;
else if (extension == "xci")
return FileType::XCI;
else if (extension == "xcz")
return FileType::XCZ;
else if (extension == "nsp")
return FileType::NSP;
else if (extension == "nsz")
return FileType::NSZ;
else if (extension == "kip")
return FileType::KIP;
return FileType::Unknown;
@@ -197,10 +202,14 @@ std::string GetFileTypeString(FileType type) {
return "NCA";
case FileType::XCI:
return "XCI";
case FileType::XCZ:
return "XCZ";
case FileType::NAX:
return "NAX";
case FileType::NSP:
return "NSP";
case FileType::NSZ:
return "NSZ";
case FileType::KIP:
return "KIP";
case FileType::DeconstructedRomDirectory:
@@ -322,6 +331,7 @@ static std::unique_ptr<AppLoader> GetFileLoader(Core::System& system, FileSys::V
// NX XCI (nX Card Image) file format.
case FileType::XCI:
case FileType::XCZ:
return std::make_unique<AppLoader_XCI>(std::move(file), system.GetFileSystemController(),
system.GetContentProvider(), program_id,
program_index);
@@ -332,6 +342,7 @@ static std::unique_ptr<AppLoader> GetFileLoader(Core::System& system, FileSys::V
// NX NSP (Nintendo Submission Package) file format
case FileType::NSP:
case FileType::NSZ:
return std::make_unique<AppLoader_NSP>(std::move(file), system.GetFileSystemController(),
system.GetContentProvider(), program_id,
program_index);
+2
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@@ -42,7 +42,9 @@ enum class FileType {
NRO,
NCA,
NSP,
NSZ,
XCI,
XCZ,
NAX,
KIP,
DeconstructedRomDirectory,
+3 -1
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@@ -163,7 +163,9 @@ inline InstallResult InstallNSP(Core::System& system, FileSys::VfsFilesystem& vf
std::shared_ptr<FileSys::NSP> nsp;
FileSys::VirtualFile file = vfs.OpenFile(filename, FileSys::OpenMode::Read);
if (boost::to_lower_copy(file->GetName()).ends_with("nsp")) {
const auto lower_name = boost::to_lower_copy(file->GetName());
if (lower_name.ends_with("nsp") || lower_name.ends_with("nsz")) {
nsp = std::make_shared<FileSys::NSP>(file);
if (nsp->IsExtractedType()) {
return InstallResult::Failure;
+7 -3
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@@ -360,7 +360,8 @@ void GameListWorker::ScanFileSystem(ScanTarget target, const std::string& dir_pa
}
if (target == ScanTarget::PopulateGameList &&
(file_type == Loader::FileType::XCI || file_type == Loader::FileType::NSP) &&
(file_type == Loader::FileType::XCI || file_type == Loader::FileType::XCZ ||
file_type == Loader::FileType::NSP || file_type == Loader::FileType::NSZ) &&
!Loader::IsBootableGameContainer(file, file_type)) {
return true;
}
@@ -375,7 +376,9 @@ void GameListWorker::ScanFileSystem(ScanTarget target, const std::string& dir_pa
program_id, file);
} else if (Settings::values.ext_content_from_game_dirs.GetValue() &&
(file_type == Loader::FileType::XCI ||
file_type == Loader::FileType::NSP)) {
file_type == Loader::FileType::XCZ ||
file_type == Loader::FileType::NSP ||
file_type == Loader::FileType::NSZ)) {
void(provider->AddEntriesFromContainer(file));
}
} else {
@@ -402,7 +405,8 @@ void GameListWorker::ScanFileSystem(ScanTarget target, const std::string& dir_pa
};
if (res2 == Loader::ResultStatus::Success && program_ids.size() > 1 &&
(file_type == Loader::FileType::XCI || file_type == Loader::FileType::NSP)) {
(file_type == Loader::FileType::XCI || file_type == Loader::FileType::XCZ ||
file_type == Loader::FileType::NSP || file_type == Loader::FileType::NSZ)) {
for (const auto id : program_ids) {
// dravee suggested this, only viable way to
// not show sub-games in qlaunch for now.
+2 -1
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@@ -57,7 +57,8 @@ std::unique_ptr<EmuThread> emu_thread = nullptr;
const QStringList supported_file_extensions = {QStringLiteral("nro"), QStringLiteral("nso"),
QStringLiteral("nca"), QStringLiteral("xci"),
QStringLiteral("nsp"), QStringLiteral("kip")};
QStringLiteral("xcz"), QStringLiteral("nsp"),
QStringLiteral("nsz"), QStringLiteral("kip")};
Core::Frontend::WindowSystemType GetWindowSystemType() {
// Determine WSI type based on Qt platform.