Rewrite Save Data & Impl Save Data Dialog (#824)

* core: Rewrite PSF parser & add encoder

add .sfo hex pattern to /scripts

* core/fs: allow to mount path as read-only

* common: Add CString wrapper to handle native null-terminated strings

* SaveData: rewrite to implement full functionality

* mock value for SYSTEM_VER

* SavaData: backup features

* SavaData: SaveDataMemory features

* imgui Ref-counted textures

- has a background thread to decode textures

* imgui: rework gamepad navigation

* PSF: fixed psf not using enum class for PSFEntryFmt (was a standard old ugly enum)

- Add null check to CString when itself is used in a nullable field

* SaveDataDialog implementation

- Fix Mounting/Unmounting check of SaveInstance

src/common/cstring.h

@@ -0,0 +1,133 @@
+// SPDX-FileCopyrightText: Copyright 2024 shadPS4 Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include <string_view>
+
+#include "assert.h"
+
+namespace Common {
+
+/**
+ * @brief A null-terminated string with a fixed maximum length
+ *        This class is not meant to be used as a general-purpose string class
+ *        It is meant to be used as `char[N]` where memory layout is fixed
+ * @tparam N Maximum length of the string
+ * @tparam T Type of character
+ */
+template <size_t N, typename T = char>
+class CString {
+    T data[N]{};
+
+public:
+    class Iterator;
+
+    CString() = default;
+
+    template <size_t M>
+    explicit CString(const CString<M>& other)
+        requires(M <= N)
+    {
+        std::ranges::copy(other.begin(), other.end(), data);
+    }
+
+    void FromString(const std::basic_string_view<T>& str) {
+        size_t p = str.copy(data, N - 1);
+        data[p] = '\0';
+    }
+
+    void Zero() {
+        std::ranges::fill(data, 0);
+    }
+
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wtautological-undefined-compare"
+    explicit(false) operator std::basic_string_view<T>() const {
+        if (this == nullptr) {
+            return {};
+        }
+        return std::basic_string_view<T>{data};
+    }
+
+    explicit operator std::basic_string<T>() const {
+        if (this == nullptr) {
+            return {};
+        }
+        return std::basic_string<T>{data};
+    }
+
+    std::basic_string<T> to_string() const {
+        if (this == nullptr) {
+            return {};
+        }
+        return std::basic_string<T>{data};
+    }
+
+    std::basic_string_view<T> to_view() const {
+        if (this == nullptr) {
+            return {};
+        }
+        return std::basic_string_view<T>{data};
+    }
+#pragma clang diagnostic pop
+
+    char* begin() {
+        return data;
+    }
+
+    const char* begin() const {
+        return data;
+    }
+
+    char* end() {
+        return data + N;
+    }
+
+    const char* end() const {
+        return data + N;
+    }
+
+    T& operator[](size_t idx) {
+        return data[idx];
+    }
+
+    const T& operator[](size_t idx) const {
+        return data[idx];
+    }
+
+    class Iterator {
+        T* ptr;
+        T* end;
+
+    public:
+        using difference_type = std::ptrdiff_t;
+        using value_type = T;
+        using pointer = T*;
+        using reference = T&;
+        using iterator_category = std::random_access_iterator_tag;
+
+        Iterator() = default;
+        explicit Iterator(T* ptr) : ptr(ptr), end(ptr + N) {}
+
+        Iterator& operator++() {
+            ++ptr;
+            return *this;
+        }
+
+        Iterator operator++(int) {
+            Iterator tmp = *this;
+            ++ptr;
+            return tmp;
+        }
+
+        operator T*() {
+            ASSERT_MSG(ptr >= end, "CString iterator out of bounds");
+            return ptr;
+        }
+    };
+};
+static_assert(sizeof(CString<13>) == sizeof(char[13])); // Ensure size still matches a simple array
+static_assert(std::weakly_incrementable<CString<13>::Iterator>);
+
+} // namespace Common

src/common/io_file.cpp

@@ -396,4 +396,18 @@ s64 IOFile::Tell() const {
     return ftello(file);
 }
 
+u64 GetDirectorySize(const std::filesystem::path& path) {
+    if (!fs::exists(path)) {
+        return 0;
+    }
+
+    u64 total = 0;
+    for (const auto& entry : fs::recursive_directory_iterator(path)) {
+        if (fs::is_regular_file(entry.path())) {
+            total += fs::file_size(entry.path());
+        }
+    }
+    return total;
+}
+
 } // namespace Common::FS

src/common/io_file.h

@@ -219,4 +219,6 @@ private:
     uintptr_t file_mapping = 0;
 };
 
+u64 GetDirectorySize(const std::filesystem::path& path);
+
 } // namespace Common::FS

src/common/string_util.cpp

@@ -14,12 +14,17 @@
 
 namespace Common {
 
-std::string ToLower(std::string str) {
-    std::transform(str.begin(), str.end(), str.begin(),
-                   [](unsigned char c) { return static_cast<char>(std::tolower(c)); });
+std::string ToLower(std::string_view input) {
+    std::string str;
+    str.resize(input.size());
+    std::ranges::transform(input, str.begin(), tolower);
     return str;
 }
 
+void ToLowerInPlace(std::string& str) {
+    std::ranges::transform(str, str.begin(), tolower);
+}
+
 std::vector<std::string> SplitString(const std::string& str, char delimiter) {
     std::istringstream iss(str);
     std::vector<std::string> output(1);

src/common/string_util.h

@@ -10,7 +10,9 @@
 namespace Common {
 
 /// Make a string lowercase
-[[nodiscard]] std::string ToLower(std::string str);
+[[nodiscard]] std::string ToLower(std::string_view str);
+
+void ToLowerInPlace(std::string& str);
 
 std::vector<std::string> SplitString(const std::string& str, char delimiter);