`string_view`-based asset lookup

Changes asset lookup functions to use `std::string_view` instead of
`const char *`.

This required new APIs in libmpq, added in
https://github.com/diasurgical/libmpq/pull/13.

3rdParty/libmpq/CMakeLists.txt

@@ -10,8 +10,8 @@ include(functions/FetchContent_MakeAvailableExcludeFromAll)
 
 include(FetchContent)
 FetchContent_Declare(libmpq
-    URL https://github.com/diasurgical/libmpq/archive/b78d66c6fee6a501cc9b95d8556a129c68841b05.tar.gz
-    URL_HASH MD5=da531a1a6f719e89798a26e679ffc329
+    URL https://github.com/diasurgical/libmpq/archive/34ace76ecb18c3c72300a6b8352ca0c96333488d.tar.gz
+    URL_HASH MD5=e76ab7e4f9dfd7f96c152dd7d8418fee
 )
 FetchContent_MakeAvailableExcludeFromAll(libmpq)
 

Source/engine/assets.cpp

@@ -3,6 +3,7 @@
 #include <algorithm>
 #include <cstdint>
 #include <cstring>
+#include <string_view>
 
 #include "init.h"
 #include "utils/file_util.h"
@@ -52,7 +53,7 @@ SDL_RWops *OpenOptionalRWops(const std::string &path)
 	return SDL_RWFromFile(path.c_str(), "rb");
 };
 
-bool FindMpqFile(const char *filename, MpqArchive **archive, uint32_t *fileNumber)
+bool FindMpqFile(std::string_view filename, MpqArchive **archive, uint32_t *fileNumber)
 {
 	const MpqArchive::FileHash fileHash = MpqArchive::CalculateFileHash(filename);
 	const auto at = [=](std::optional<MpqArchive> &src) -> bool {
@@ -71,16 +72,15 @@ bool FindMpqFile(const char *filename, MpqArchive **archive, uint32_t *fileNumbe
 } // namespace
 
 #ifdef UNPACKED_MPQS
-AssetRef FindAsset(const char *filename)
+AssetRef FindAsset(std::string_view filename)
 {
 	AssetRef result;
 	result.path[0] = '\0';
 
-	const std::string_view filenameStr = filename;
 	char pathBuf[AssetRef::PathBufSize];
 	char *const pathEnd = pathBuf + AssetRef::PathBufSize;
-	char *const relativePath = &pathBuf[AssetRef::PathBufSize - filenameStr.size() - 1];
-	*BufCopy(relativePath, filenameStr) = '\0';
+	char *const relativePath = &pathBuf[AssetRef::PathBufSize - filename.size() - 1];
+	*BufCopy(relativePath, filename) = '\0';
 
 #ifndef _WIN32
 	std::replace(relativePath, pathEnd, '\\', '/');
@@ -88,7 +88,7 @@ AssetRef FindAsset(const char *filename)
 	// Absolute path:
 	if (relativePath[0] == '/') {
 		if (FileExists(relativePath)) {
-			*BufCopy(result.path, std::string_view(relativePath, filenameStr.size())) = '\0';
+			*BufCopy(result.path, std::string_view(relativePath, filename.size())) = '\0';
 		}
 		return result;
 	}
@@ -110,10 +110,10 @@ AssetRef FindAsset(const char *filename)
 	return result;
 }
 #else
-AssetRef FindAsset(const char *filename)
+AssetRef FindAsset(std::string_view filename)
 {
 	AssetRef result;
-	std::string relativePath = filename;
+	std::string relativePath { filename };
 #ifndef _WIN32
 	std::replace(relativePath.begin(), relativePath.end(), '\\', '/');
 #endif
@@ -177,7 +177,7 @@ AssetHandle OpenAsset(AssetRef &&ref, bool threadsafe)
 #endif
 }
 
-AssetHandle OpenAsset(const char *filename, bool threadsafe)
+AssetHandle OpenAsset(std::string_view filename, bool threadsafe)
 {
 	AssetRef ref = FindAsset(filename);
 	if (!ref.ok())
@@ -185,7 +185,7 @@ AssetHandle OpenAsset(const char *filename, bool threadsafe)
 	return OpenAsset(std::move(ref), threadsafe);
 }
 
-AssetHandle OpenAsset(const char *filename, size_t &fileSize, bool threadsafe)
+AssetHandle OpenAsset(std::string_view filename, size_t &fileSize, bool threadsafe)
 {
 	AssetRef ref = FindAsset(filename);
 	if (!ref.ok())
@@ -194,7 +194,7 @@ AssetHandle OpenAsset(const char *filename, size_t &fileSize, bool threadsafe)
 	return OpenAsset(std::move(ref), threadsafe);
 }
 
-SDL_RWops *OpenAssetAsSdlRwOps(const char *filename, bool threadsafe)
+SDL_RWops *OpenAssetAsSdlRwOps(std::string_view filename, bool threadsafe)
 {
 #ifdef UNPACKED_MPQS
 	AssetRef ref = FindAsset(filename);

Source/engine/assets.hpp

@@ -4,6 +4,7 @@
 #include <cstdint>
 #include <cstdio>
 #include <string>
+#include <string_view>
 
 #include <SDL.h>
 
@@ -96,7 +97,7 @@ struct AssetRef {
 	// An MPQ file reference:
 	MpqArchive *archive = nullptr;
 	uint32_t fileNumber;
-	const char *filename;
+	std::string_view filename;
 
 	// Alternatively, a direct SDL_RWops handle:
 	SDL_RWops *directHandle = nullptr;
@@ -212,12 +213,12 @@ struct AssetHandle {
 };
 #endif
 
-[[noreturn]] inline void FailedToOpenFileError(const char *path, const char *error)
+[[noreturn]] inline void FailedToOpenFileError(std::string_view path, std::string_view error)
 {
 	app_fatal(StrCat("Failed to open file:\n", path, "\n\n", error));
 }
 
-inline bool ValidatAssetRef(const char *path, const AssetRef &ref)
+inline bool ValidatAssetRef(std::string_view path, const AssetRef &ref)
 {
 	if (ref.ok())
 		return true;
@@ -227,7 +228,7 @@ inline bool ValidatAssetRef(const char *path, const AssetRef &ref)
 	return false;
 }
 
-inline bool ValidateHandle(const char *path, const AssetHandle &handle)
+inline bool ValidateHandle(std::string_view path, const AssetHandle &handle)
 {
 	if (handle.ok())
 		return true;
@@ -237,12 +238,12 @@ inline bool ValidateHandle(const char *path, const AssetHandle &handle)
 	return false;
 }
 
-AssetRef FindAsset(const char *filename);
+AssetRef FindAsset(std::string_view filename);
 
 AssetHandle OpenAsset(AssetRef &&ref, bool threadsafe = false);
-AssetHandle OpenAsset(const char *filename, bool threadsafe = false);
-AssetHandle OpenAsset(const char *filename, size_t &fileSize, bool threadsafe = false);
+AssetHandle OpenAsset(std::string_view filename, bool threadsafe = false);
+AssetHandle OpenAsset(std::string_view filename, size_t &fileSize, bool threadsafe = false);
 
-SDL_RWops *OpenAssetAsSdlRwOps(const char *filename, bool threadsafe = false);
+SDL_RWops *OpenAssetAsSdlRwOps(std::string_view filename, bool threadsafe = false);
 
 } // namespace devilution

Source/mpq/mpq_reader.cpp

@@ -2,6 +2,7 @@
 
 #include <cstdint>
 #include <optional>
+#include <string_view>
 
 #include <libmpq/mpq.h>
 
@@ -33,10 +34,10 @@ const char *MpqArchive::ErrorMessage(int32_t errorCode)
 	return libmpq__strerror(errorCode);
 }
 
-MpqArchive::FileHash MpqArchive::CalculateFileHash(const char *filename)
+MpqArchive::FileHash MpqArchive::CalculateFileHash(std::string_view filename)
 {
 	FileHash fileHash;
-	libmpq__file_hash(filename, &fileHash[0], &fileHash[1], &fileHash[2]);
+	libmpq__file_hash_s(filename.data(), filename.size(), &fileHash[0], &fileHash[1], &fileHash[2]);
 	return fileHash;
 }
 
@@ -61,11 +62,11 @@ bool MpqArchive::GetFileNumber(MpqArchive::FileHash fileHash, uint32_t &fileNumb
 	return libmpq__file_number_from_hash(archive_, fileHash[0], fileHash[1], fileHash[2], &fileNumber) == 0;
 }
 
-std::unique_ptr<std::byte[]> MpqArchive::ReadFile(const char *filename, std::size_t &fileSize, int32_t &error)
+std::unique_ptr<std::byte[]> MpqArchive::ReadFile(std::string_view filename, std::size_t &fileSize, int32_t &error)
 {
 	std::unique_ptr<std::byte[]> result;
 	std::uint32_t fileNumber;
-	error = libmpq__file_number(archive_, filename, &fileNumber);
+	error = libmpq__file_number_s(archive_, filename.data(), filename.size(), &fileNumber);
 	if (error != 0)
 		return result;
 
@@ -88,8 +89,8 @@ std::unique_ptr<std::byte[]> MpqArchive::ReadFile(const char *filename, std::siz
 	if (error != 0)
 		return result;
 
-	error = libmpq__file_read_with_filename_and_temporary_buffer(
-	    archive_, fileNumber, filename, reinterpret_cast<std::uint8_t *>(result.get()), unpackedSize,
+	error = libmpq__file_read_with_filename_and_temporary_buffer_s(
+	    archive_, fileNumber, filename.data(), filename.size(), reinterpret_cast<std::uint8_t *>(result.get()), unpackedSize,
 	    tmp.data(), static_cast<libmpq__off_t>(blockSize), nullptr);
 	if (error != 0) {
 		result = nullptr;
@@ -125,9 +126,9 @@ uint32_t MpqArchive::GetNumBlocks(uint32_t fileNumber, int32_t &error)
 	return numBlocks;
 }
 
-int32_t MpqArchive::OpenBlockOffsetTable(uint32_t fileNumber, const char *filename)
+int32_t MpqArchive::OpenBlockOffsetTable(uint32_t fileNumber, std::string_view filename)
 {
-	return libmpq__block_open_offset_with_filename(archive_, fileNumber, filename);
+	return libmpq__block_open_offset_with_filename_s(archive_, fileNumber, filename.data(), filename.size());
 }
 
 int32_t MpqArchive::CloseBlockOffsetTable(uint32_t fileNumber)
@@ -143,10 +144,10 @@ std::size_t MpqArchive::GetBlockSize(uint32_t fileNumber, uint32_t blockNumber,
 	return blockSize;
 }
 
-bool MpqArchive::HasFile(const char *filename) const
+bool MpqArchive::HasFile(std::string_view filename) const
 {
 	std::uint32_t fileNumber;
-	int32_t error = libmpq__file_number(archive_, filename, &fileNumber);
+	int32_t error = libmpq__file_number_s(archive_, filename.data(), filename.size(), &fileNumber);
 	return error == 0;
 }
 

Source/mpq/mpq_reader.hpp

@@ -6,6 +6,7 @@
 #include <memory>
 #include <optional>
 #include <string>
+#include <string_view>
 #include <vector>
 
 // Forward-declare so that we can avoid exposing libmpq.
@@ -24,7 +25,7 @@ public:
 	static const char *ErrorMessage(int32_t errorCode);
 
 	using FileHash = std::array<std::uint32_t, 3>;
-	static FileHash CalculateFileHash(const char *filename);
+	static FileHash CalculateFileHash(std::string_view filename);
 
 	MpqArchive(MpqArchive &&other) noexcept
 	    : path_(std::move(other.path_))
@@ -41,7 +42,7 @@ public:
 	// Returns false if the file does not exit.
 	bool GetFileNumber(FileHash fileHash, uint32_t &fileNumber);
 
-	std::unique_ptr<std::byte[]> ReadFile(const char *filename, std::size_t &fileSize, int32_t &error);
+	std::unique_ptr<std::byte[]> ReadFile(std::string_view filename, std::size_t &fileSize, int32_t &error);
 
 	// Returns error code.
 	int32_t ReadBlock(uint32_t fileNumber, uint32_t blockNumber, uint8_t *out, uint32_t outSize);
@@ -50,14 +51,14 @@ public:
 
 	uint32_t GetNumBlocks(uint32_t fileNumber, int32_t &error);
 
-	int32_t OpenBlockOffsetTable(uint32_t fileNumber, const char *filename);
+	int32_t OpenBlockOffsetTable(uint32_t fileNumber, std::string_view filename);
 
 	int32_t CloseBlockOffsetTable(uint32_t fileNumber);
 
 	// Requires the block offset table to be open
 	std::size_t GetBlockSize(uint32_t fileNumber, uint32_t blockNumber, int32_t &error);
 
-	bool HasFile(const char *filename) const;
+	bool HasFile(std::string_view filename) const;
 
 private:
 	MpqArchive(std::string path, mpq_archive_s *archive)

Source/mpq/mpq_sdl_rwops.cpp

@@ -3,6 +3,7 @@
 #include <cstdint>
 #include <cstring>
 #include <memory>
+#include <string_view>
 #include <vector>
 
 namespace devilution {
@@ -153,7 +154,7 @@ static int MpqFileRwClose(struct SDL_RWops *context)
 
 } // namespace
 
-SDL_RWops *SDL_RWops_FromMpqFile(MpqArchive &mpqArchive, uint32_t fileNumber, const char *filename, bool threadsafe)
+SDL_RWops *SDL_RWops_FromMpqFile(MpqArchive &mpqArchive, uint32_t fileNumber, std::string_view filename, bool threadsafe)
 {
 	auto result = std::make_unique<SDL_RWops>();
 	std::memset(result.get(), 0, sizeof(*result));

Source/mpq/mpq_sdl_rwops.hpp

@@ -1,6 +1,7 @@
 #pragma once
 
 #include <cstdint>
+#include <string_view>
 
 #include <SDL.h>
 
@@ -8,6 +9,6 @@
 
 namespace devilution {
 
-SDL_RWops *SDL_RWops_FromMpqFile(MpqArchive &mpqArchive, uint32_t fileNumber, const char *filename, bool threadsafe);
+SDL_RWops *SDL_RWops_FromMpqFile(MpqArchive &mpqArchive, uint32_t fileNumber, std::string_view filename, bool threadsafe);
 
 } // namespace devilution