common: fs: fs_util: Add more string conversion functions

src/common/fs/fs_util.cpp

@@ -2,6 +2,8 @@
 // Licensed under GPLv2 or any later version
 // Refer to the license.txt file included.
 
+#include <algorithm>
+
 #include "common/fs/fs_util.h"
 
 namespace Common::FS {
@@ -10,4 +12,12 @@ std::u8string ToU8String(std::string_view utf8_string) {
     return std::u8string{utf8_string.begin(), utf8_string.end()};
 }
 
+std::u8string BufferToU8String(std::span<const u8> buffer) {
+    return std::u8string{buffer.begin(), std::ranges::find(buffer, u8{0})};
+}
+
+std::string ToUTF8String(std::u8string_view u8_string) {
+    return std::string{u8_string.begin(), u8_string.end()};
+}
+
 } // namespace Common::FS

src/common/fs/fs_util.h

@@ -5,9 +5,12 @@
 #pragma once
 
 #include <concepts>
+#include <span>
 #include <string>
 #include <string_view>
 
+#include "common/common_types.h"
+
 namespace Common::FS {
 
 template <typename T>
@@ -22,4 +25,24 @@ concept IsChar = std::same_as<T, char>;
  */
 [[nodiscard]] std::u8string ToU8String(std::string_view utf8_string);
 
+/**
+ * Converts a buffer of bytes to a UTF8-encoded std::u8string.
+ * This converts from the start of the buffer until the first encountered null-terminator.
+ * If no null-terminator is found, this converts the entire buffer instead.
+ *
+ * @param buffer Buffer of bytes
+ *
+ * @returns UTF-8 encoded std::u8string.
+ */
+[[nodiscard]] std::u8string BufferToU8String(std::span<const u8> buffer);
+
+/**
+ * Converts a std::u8string or std::u8string_view to a UTF-8 encoded std::string.
+ *
+ * @param u8_string UTF-8 encoded u8string
+ *
+ * @returns UTF-8 encoded std::string.
+ */
+[[nodiscard]] std::string ToUTF8String(std::u8string_view u8_string);
+
 } // namespace Common::FS