Merge pull request #4698 from lioncash/optional-null

General: Make use of std::nullopt where applicable

10 files changed, 31 insertions, 27 deletions

diff --git a/src/core/arm/dynarmic/arm_dynarmic_cp15.cpp b/src/core/arm/dynarmic/arm_dynarmic_cp15.cpp
index 54556e0f9..caefc09f4 100644
--- a/src/core/arm/dynarmic/arm_dynarmic_cp15.cpp
+++ b/src/core/arm/dynarmic/arm_dynarmic_cp15.cpp
@@ -34,7 +34,7 @@ std::optional<Callback> DynarmicCP15::CompileInternalOperation(bool two, unsigne
                                                                CoprocReg CRm, unsigned opc2) {
     LOG_CRITICAL(Core_ARM, "CP15: cdp{} p15, {}, {}, {}, {}, {}", two ? "2" : "", opc1, CRd, CRn,
                  CRm, opc2);
-    return {};
+    return std::nullopt;
 }
 
 CallbackOrAccessOneWord DynarmicCP15::CompileSendOneWord(bool two, unsigned opc1, CoprocReg CRn,
@@ -115,7 +115,7 @@ std::optional<Callback> DynarmicCP15::CompileLoadWords(bool two, bool long_trans
         LOG_CRITICAL(Core_ARM, "CP15: mrrc{}{} p15, {}, [...]", two ? "2" : "",
                      long_transfer ? "l" : "", CRd);
     }
-    return {};
+    return std::nullopt;
 }
 
 std::optional<Callback> DynarmicCP15::CompileStoreWords(bool two, bool long_transfer, CoprocReg CRd,
@@ -127,7 +127,7 @@ std::optional<Callback> DynarmicCP15::CompileStoreWords(bool two, bool long_tran
         LOG_CRITICAL(Core_ARM, "CP15: mrrc{}{} p15, {}, [...]", two ? "2" : "",
                      long_transfer ? "l" : "", CRd);
     }
-    return {};
+    return std::nullopt;
 }
 
 } // namespace Core
diff --git a/src/core/file_sys/content_archive.cpp b/src/core/file_sys/content_archive.cpp
index 426fb6bb5..76af47ff9 100644
--- a/src/core/file_sys/content_archive.cpp
+++ b/src/core/file_sys/content_archive.cpp
@@ -323,7 +323,7 @@ bool NCA::ReadRomFSSection(const NCASectionHeader& section, const NCASectionTabl
         subsection_buckets.back().entries.push_back({section.bktr.relocation.offset, {0}, ctr_low});
         subsection_buckets.back().entries.push_back({size, {0}, 0});
 
-        std::optional<Core::Crypto::Key128> key = {};
+        std::optional<Core::Crypto::Key128> key;
         if (encrypted) {
             if (has_rights_id) {
                 status = Loader::ResultStatus::Success;
@@ -442,18 +442,18 @@ std::optional<Core::Crypto::Key128> NCA::GetTitlekey() {
     memcpy(rights_id.data(), header.rights_id.data(), 16);
     if (rights_id == u128{}) {
         status = Loader::ResultStatus::ErrorInvalidRightsID;
-        return {};
+        return std::nullopt;
     }
 
     auto titlekey = keys.GetKey(Core::Crypto::S128KeyType::Titlekey, rights_id[1], rights_id[0]);
     if (titlekey == Core::Crypto::Key128{}) {
         status = Loader::ResultStatus::ErrorMissingTitlekey;
-        return {};
+        return std::nullopt;
     }
 
     if (!keys.HasKey(Core::Crypto::S128KeyType::Titlekek, master_key_id)) {
         status = Loader::ResultStatus::ErrorMissingTitlekek;
-        return {};
+        return std::nullopt;
     }
 
     Core::Crypto::AESCipher<Core::Crypto::Key128> cipher(
@@ -477,7 +477,7 @@ VirtualFile NCA::Decrypt(const NCASectionHeader& s_header, VirtualFile in, u64 s
     case NCASectionCryptoType::BKTR:
         LOG_TRACE(Crypto, "called with mode=CTR, starting_offset={:016X}", starting_offset);
         {
-            std::optional<Core::Crypto::Key128> key = {};
+            std::optional<Core::Crypto::Key128> key;
             if (has_rights_id) {
                 status = Loader::ResultStatus::Success;
                 key = GetTitlekey();
diff --git a/src/core/file_sys/vfs.cpp b/src/core/file_sys/vfs.cpp
index a4c3f67c4..b2f026b6d 100644
--- a/src/core/file_sys/vfs.cpp
+++ b/src/core/file_sys/vfs.cpp
@@ -169,11 +169,12 @@ VfsDirectory::~VfsDirectory() = default;
 
 std::optional<u8> VfsFile::ReadByte(std::size_t offset) const {
     u8 out{};
-    std::size_t size = Read(&out, 1, offset);
-    if (size == 1)
+    const std::size_t size = Read(&out, sizeof(u8), offset);
+    if (size == 1) {
         return out;
+    }
 
-    return {};
+    return std::nullopt;
 }
 
 std::vector<u8> VfsFile::ReadBytes(std::size_t size, std::size_t offset) const {
diff --git a/src/core/file_sys/vfs_offset.cpp b/src/core/file_sys/vfs_offset.cpp
index c96f88488..7714d3de5 100644
--- a/src/core/file_sys/vfs_offset.cpp
+++ b/src/core/file_sys/vfs_offset.cpp
@@ -58,10 +58,11 @@ std::size_t OffsetVfsFile::Write(const u8* data, std::size_t length, std::size_t
 }
 
 std::optional<u8> OffsetVfsFile::ReadByte(std::size_t r_offset) const {
-    if (r_offset < size)
-        return file->ReadByte(offset + r_offset);
+    if (r_offset >= size) {
+        return std::nullopt;
+    }
 
-    return {};
+    return file->ReadByte(offset + r_offset);
 }
 
 std::vector<u8> OffsetVfsFile::ReadBytes(std::size_t r_size, std::size_t r_offset) const {
diff --git a/src/core/file_sys/vfs_static.h b/src/core/file_sys/vfs_static.h
index 9f5a90b1b..8b27c30fa 100644
--- a/src/core/file_sys/vfs_static.h
+++ b/src/core/file_sys/vfs_static.h
@@ -54,9 +54,11 @@ public:
     }
 
     std::optional<u8> ReadByte(std::size_t offset) const override {
-        if (offset < size)
-            return value;
-        return {};
+        if (offset >= size) {
+            return std::nullopt;
+        }
+
+        return value;
     }
 
     std::vector<u8> ReadBytes(std::size_t length, std::size_t offset) const override {
diff --git a/src/core/hle/service/nvdrv/devices/nvhost_as_gpu.cpp b/src/core/hle/service/nvdrv/devices/nvhost_as_gpu.cpp
index d4ba88147..39bd2a45b 100644
--- a/src/core/hle/service/nvdrv/devices/nvhost_as_gpu.cpp
+++ b/src/core/hle/service/nvdrv/devices/nvhost_as_gpu.cpp
@@ -265,7 +265,7 @@ std::optional<nvhost_as_gpu::BufferMap> nvhost_as_gpu::FindBufferMap(GPUVAddr gp
         }
     }
 
-    return {};
+    return std::nullopt;
 }
 
 void nvhost_as_gpu::AddBufferMap(GPUVAddr gpu_addr, std::size_t size, VAddr cpu_addr,
@@ -286,7 +286,7 @@ std::optional<std::size_t> nvhost_as_gpu::RemoveBufferMap(GPUVAddr gpu_addr) {
         return size;
     }
 
-    return {};
+    return std::nullopt;
 }
 
 } // namespace Service::Nvidia::Devices
diff --git a/src/core/hle/service/nvdrv/nvdrv.h b/src/core/hle/service/nvdrv/nvdrv.h
index d7a1bef91..7706a5590 100644
--- a/src/core/hle/service/nvdrv/nvdrv.h
+++ b/src/core/hle/service/nvdrv/nvdrv.h
@@ -54,7 +54,7 @@ struct EventInterface {
             }
             mask = mask >> 1;
         }
-        return {};
+        return std::nullopt;
     }
     void SetEventStatus(const u32 event_id, EventState new_status) {
         EventState old_status = status[event_id];
diff --git a/src/core/hle/service/nvflinger/nvflinger.cpp b/src/core/hle/service/nvflinger/nvflinger.cpp
index f644a460d..c64673dba 100644
--- a/src/core/hle/service/nvflinger/nvflinger.cpp
+++ b/src/core/hle/service/nvflinger/nvflinger.cpp
@@ -114,7 +114,7 @@ std::optional<u64> NVFlinger::OpenDisplay(std::string_view name) {
                      [&](const VI::Display& display) { return display.GetName() == name; });
 
     if (itr == displays.end()) {
-        return {};
+        return std::nullopt;
     }
 
     return itr->GetID();
@@ -124,7 +124,7 @@ std::optional<u64> NVFlinger::CreateLayer(u64 display_id) {
     auto* const display = FindDisplay(display_id);
 
     if (display == nullptr) {
-        return {};
+        return std::nullopt;
     }
 
     const u64 layer_id = next_layer_id++;
@@ -144,7 +144,7 @@ std::optional<u32> NVFlinger::FindBufferQueueId(u64 display_id, u64 layer_id) co
     const auto* const layer = FindLayer(display_id, layer_id);
 
     if (layer == nullptr) {
-        return {};
+        return std::nullopt;
     }
 
     return layer->GetBufferQueue().GetId();
diff --git a/src/core/hle/service/sockets/bsd.cpp b/src/core/hle/service/sockets/bsd.cpp
index 7b9dd42d8..a74be9370 100644
--- a/src/core/hle/service/sockets/bsd.cpp
+++ b/src/core/hle/service/sockets/bsd.cpp
@@ -497,7 +497,7 @@ std::pair<s32, Errno> BSD::PollImpl(std::vector<u8>& write_buffer, std::vector<u
             return {0, Errno::SUCCESS};
         }
 
-        std::optional<FileDescriptor>& descriptor = file_descriptors[pollfd.fd];
+        const std::optional<FileDescriptor>& descriptor = file_descriptors[pollfd.fd];
         if (!descriptor) {
             LOG_ERROR(Service, "File descriptor handle={} is not allocated", pollfd.fd);
             pollfd.revents = POLL_NVAL;
diff --git a/src/core/loader/nso.cpp b/src/core/loader/nso.cpp
index 60373cc5f..1e70f6e11 100644
--- a/src/core/loader/nso.cpp
+++ b/src/core/loader/nso.cpp
@@ -76,16 +76,16 @@ std::optional<VAddr> AppLoader_NSO::LoadModule(Kernel::Process& process, Core::S
                                                bool should_pass_arguments, bool load_into_process,
                                                std::optional<FileSys::PatchManager> pm) {
     if (file.GetSize() < sizeof(NSOHeader)) {
-        return {};
+        return std::nullopt;
     }
 
     NSOHeader nso_header{};
     if (sizeof(NSOHeader) != file.ReadObject(&nso_header)) {
-        return {};
+        return std::nullopt;
     }
 
     if (nso_header.magic != Common::MakeMagic('N', 'S', 'O', '0')) {
-        return {};
+        return std::nullopt;
     }
 
     // Build program image