Add support for WUHB file format (#1190)

src/Cafe/Filesystem/fscDeviceWuhb.cpp

@@ -0,0 +1,151 @@
+#include "Filesystem/WUHB/WUHBReader.h"
+#include "Cafe/Filesystem/fsc.h"
+#include "Cafe/Filesystem/FST/FST.h"
+
+class FSCDeviceWuhbFileCtx : public FSCVirtualFile
+{
+  public:
+	FSCDeviceWuhbFileCtx(WUHBReader* reader, uint32 entryOffset, uint32 fscType)
+		: m_wuhbReader(reader), m_entryOffset(entryOffset), m_fscType(fscType)
+	{
+		cemu_assert(entryOffset != ROMFS_ENTRY_EMPTY);
+		if (fscType == FSC_TYPE_DIRECTORY)
+		{
+			romfs_direntry_t entry = reader->GetDirEntry(entryOffset);
+			m_dirIterOffset = entry.dirListHead;
+			m_fileIterOffset = entry.fileListHead;
+		}
+	}
+	sint32 fscGetType() override
+	{
+		return m_fscType;
+	}
+	uint64 fscQueryValueU64(uint32 id) override
+	{
+		if (m_fscType == FSC_TYPE_FILE)
+		{
+			if (id == FSC_QUERY_SIZE)
+				return m_wuhbReader->GetFileSize(m_entryOffset);
+			else if (id == FSC_QUERY_WRITEABLE)
+				return 0; // WUHB images are read-only
+			else
+				cemu_assert_error();
+		}
+		else
+		{
+			cemu_assert_unimplemented();
+		}
+		return 0;
+	}
+	uint32 fscWriteData(void* buffer, uint32 size) override
+	{
+		cemu_assert_error();
+		return 0;
+	}
+	uint32 fscReadData(void* buffer, uint32 size) override
+	{
+		if (m_fscType != FSC_TYPE_FILE)
+			return 0;
+		auto read = m_wuhbReader->ReadFromFile(m_entryOffset, m_seek, size, buffer);
+		m_seek += read;
+		return read;
+	}
+	void fscSetSeek(uint64 seek) override
+	{
+		m_seek = seek;
+	}
+	uint64 fscGetSeek() override
+	{
+		if (m_fscType != FSC_TYPE_FILE)
+			return 0;
+		return m_seek;
+	}
+	void fscSetFileLength(uint64 endOffset) override
+	{
+		cemu_assert_error();
+	}
+	bool fscDirNext(FSCDirEntry* dirEntry) override
+	{
+		if (m_dirIterOffset != ROMFS_ENTRY_EMPTY)
+		{
+			romfs_direntry_t entry = m_wuhbReader->GetDirEntry(m_dirIterOffset);
+			m_dirIterOffset = entry.listNext;
+			if(entry.name_size > 0)
+			{
+				dirEntry->isDirectory = true;
+				dirEntry->isFile = false;
+				dirEntry->fileSize = 0;
+				std::strncpy(dirEntry->path, entry.name.c_str(), FSC_MAX_DIR_NAME_LENGTH);
+				return true;
+			}
+		}
+		if (m_fileIterOffset != ROMFS_ENTRY_EMPTY)
+		{
+			romfs_fentry_t entry = m_wuhbReader->GetFileEntry(m_fileIterOffset);
+			m_fileIterOffset = entry.listNext;
+			if(entry.name_size > 0)
+			{
+				dirEntry->isDirectory = false;
+				dirEntry->isFile = true;
+				dirEntry->fileSize = entry.size;
+				std::strncpy(dirEntry->path, entry.name.c_str(), FSC_MAX_DIR_NAME_LENGTH);
+				return true;
+			}
+		}
+
+		return false;
+	}
+
+  private:
+	WUHBReader* m_wuhbReader{};
+	uint32 m_fscType;
+	uint32 m_entryOffset = ROMFS_ENTRY_EMPTY;
+	uint32 m_dirIterOffset = ROMFS_ENTRY_EMPTY;
+	uint32 m_fileIterOffset = ROMFS_ENTRY_EMPTY;
+	uint64 m_seek = 0;
+};
+
+class fscDeviceWUHB : public fscDeviceC
+{
+	FSCVirtualFile* fscDeviceOpenByPath(std::string_view path, FSC_ACCESS_FLAG accessFlags, void* ctx, sint32* fscStatus) override
+	{
+		WUHBReader* reader = (WUHBReader*)ctx;
+		cemu_assert_debug(!HAS_FLAG(accessFlags, FSC_ACCESS_FLAG::WRITE_PERMISSION)); // writing to WUHB is not supported
+
+		bool isFile;
+		uint32 table_offset = ROMFS_ENTRY_EMPTY;
+
+		if (table_offset == ROMFS_ENTRY_EMPTY && HAS_FLAG(accessFlags, FSC_ACCESS_FLAG::OPEN_DIR))
+		{
+			table_offset = reader->Lookup(path, false);
+			isFile = false;
+		}
+		if (table_offset == ROMFS_ENTRY_EMPTY && HAS_FLAG(accessFlags, FSC_ACCESS_FLAG::OPEN_FILE))
+		{
+			table_offset = reader->Lookup(path, true);
+			isFile = true;
+		}
+
+		if (table_offset == ROMFS_ENTRY_EMPTY)
+		{
+			*fscStatus = FSC_STATUS_FILE_NOT_FOUND;
+			return nullptr;
+		}
+
+		*fscStatus = FSC_STATUS_OK;
+		return new FSCDeviceWuhbFileCtx(reader, table_offset, isFile ? FSC_TYPE_FILE : FSC_TYPE_DIRECTORY);
+	}
+
+	// singleton
+  public:
+	static fscDeviceWUHB& instance()
+	{
+		static fscDeviceWUHB _instance;
+		return _instance;
+	}
+};
+
+bool FSCDeviceWUHB_Mount(std::string_view mountPath, std::string_view destinationBaseDir, WUHBReader* wuhbReader, sint32 priority)
+{
+	return fsc_mount(mountPath, destinationBaseDir, &fscDeviceWUHB::instance(), wuhbReader, priority) == FSC_STATUS_OK;
+}