Switch libraries for sha3 256, move implementation to source file

The previous library we used (picosha3) returned a wrong hash for one
particular file. Though this was quite rare (we only found 1 such file),
it was a bug with the library regardless.
The current sha3 library now comes from
https://github.com/stbrumme/hash-library

loader/CMakeLists.txt

@@ -55,6 +55,7 @@ file(GLOB SOURCES CONFIGURE_DEPENDS
 	src/ui/internal/info/*.cpp
 	src/ui/internal/list/*.cpp
 	src/ui/internal/settings/*.cpp
+	hash/hash.cpp
 )
 
 # Obj-c sources

loader/hash/CMakeLists.txt

@@ -2,7 +2,7 @@ cmake_minimum_required(VERSION 3.0 FATAL_ERROR)
 
 project(GeodeChecksum VERSION 1.0)
 
-add_executable(${PROJECT_NAME} hash.cpp)
+add_executable(${PROJECT_NAME} main.cpp hash.cpp)
 target_compile_features(${PROJECT_NAME} PUBLIC cxx_std_20)
 
 target_link_libraries(${PROJECT_NAME} PUBLIC ghc_filesystem)

loader/hash/hash.cpp

@@ -1,11 +1,44 @@
-#include <iostream>
 #include "hash.hpp"
 
-int main(int argc, char** argv) {
-    if (argc < 2 || !ghc::filesystem::exists(argv[1])) {
-        std::cout << "Usage: \"checksum <file>\"\n";
-        return 1;
+// shh, its fine :-)
+#include "sha3.cpp"
+
+#include <string>
+#include <fstream>
+#include <ciso646>
+#include "picosha2.h"
+#include <vector>
+
+template <class Func>
+void readBuffered(std::ifstream& stream, Func func) {
+    constexpr size_t BUF_SIZE = 4096;
+    stream.exceptions(std::ios_base::badbit);
+
+    std::vector<uint8_t> buffer(BUF_SIZE);
+    while (true) {
+        stream.read(reinterpret_cast<char*>(buffer.data()), BUF_SIZE);
+        size_t amt = stream ? BUF_SIZE : stream.gcount();
+        func(buffer.data(), amt);
+        if (!stream) break;
     }
-    std::cout << calculateHash(argv[1]) << std::endl;
-    return 0;
 }
+
+std::string calculateSHA3_256(ghc::filesystem::path const& path) {
+    std::ifstream file(path, std::ios::binary);
+    SHA3 sha;
+    readBuffered(file, [&](const void* data, size_t amt) {
+        sha.add(data, amt);
+    });
+    return sha.getHash();
+}
+
+std::string calculateSHA256(ghc::filesystem::path const& path) {
+    std::vector<uint8_t> hash(picosha2::k_digest_size);
+    std::ifstream file(path, std::ios::binary);
+    picosha2::hash256(file, hash.begin(), hash.end());
+    return picosha2::bytes_to_hex_string(hash.begin(), hash.end());
+}
+
+std::string calculateHash(ghc::filesystem::path const& path) {
+    return calculateSHA3_256(path);
+}

loader/hash/hash.hpp

@@ -1,27 +1,10 @@
 #pragma once
 
 #include <string>
-#include <fstream>
-#include <ciso646>
-#include "picosha3.h"
-#include "picosha2.h"
-#include <vector>
 #include <ghc/filesystem.hpp>
 
-static std::string calculateSHA3_256(ghc::filesystem::path const& path) {
-    std::vector<uint8_t> s(picosha3::bits_to_bytes(256));
-    auto sha3_256 = picosha3::get_sha3_generator<256>();
-    std::ifstream file(path, std::ios::binary);
-    return sha3_256.get_hex_string(file);
-}
+std::string calculateSHA3_256(ghc::filesystem::path const& path);
 
-static std::string calculateSHA256(ghc::filesystem::path const& path) {
-    std::vector<uint8_t> hash(picosha2::k_digest_size);
-    std::ifstream file(path, std::ios::binary);
-    picosha2::hash256(file, hash.begin(), hash.end());
-    return picosha2::bytes_to_hex_string(hash.begin(), hash.end());
-}
+std::string calculateSHA256(ghc::filesystem::path const& path);
 
-static std::string calculateHash(ghc::filesystem::path const& path) {
-    return calculateSHA3_256(path);
-}
+std::string calculateHash(ghc::filesystem::path const& path);

loader/hash/main.cpp

@@ -0,0 +1,11 @@
+#include <iostream>
+#include "hash.hpp"
+
+int main(int argc, char** argv) {
+    if (argc < 2 || !ghc::filesystem::exists(argv[1])) {
+        std::cout << "Usage: \"checksum <file>\"\n";
+        return 1;
+    }
+    std::cout << calculateHash(argv[1]) << std::endl;
+    return 0;
+}