utils: code dedupe

5 files changed, 82 insertions, 43 deletions

diff --git a/utils/CMakeLists.txt b/utils/CMakeLists.txt
index 5db82b3..e13d7ce 100644
--- a/utils/CMakeLists.txt
+++ b/utils/CMakeLists.txt
@@ -1,3 +1,7 @@
+if(MSVC)
+    add_definitions(/DNOMINMAX)
+endif()
+
 find_package(Boost REQUIRED COMPONENTS filesystem program_options system)
 
 add_executable(util_encrypt_block encrypt_block.cpp block_cmd_parser.hpp block_dumper.hpp block_input.hpp data_parsers.hpp)
diff --git a/utils/decrypt_bmp.cpp b/utils/decrypt_bmp.cpp
index 4842fbd..1d287d2 100644
--- a/utils/decrypt_bmp.cpp
+++ b/utils/decrypt_bmp.cpp
@@ -4,6 +4,7 @@
 // Distributed under the MIT License.
 
 #include "file_cmd_parser.hpp"
+#include "helpers/bmp.hpp"
 #include "helpers/file.hpp"
 
 #include <aesxx/all.hpp>
@@ -12,12 +13,9 @@
 
 #include <boost/program_options.hpp>
 
-#include <cstring>
-
 #include <exception>
 #include <iostream>
 #include <string>
-#include <vector>
 
 namespace
 {
@@ -26,22 +24,11 @@ namespace
         const std::string& ciphertext_path,
         const std::string& plaintext_path)
     {
-        const auto ciphertext_buf = file::read_file(ciphertext_path);
-
-        const auto bmp_header = reinterpret_cast<const BITMAPFILEHEADER*>(ciphertext_buf.data());
-
-        const auto header_size = bmp_header->bfOffBits;
-        const auto cipherpixels = ciphertext_buf.data() + header_size;
-        const auto cipherpixels_size = ciphertext_buf.size() - header_size;
-
-        const auto pixels = box.decrypt_buffer(
-            cipherpixels, cipherpixels_size);
-
-        std::vector<unsigned char> plaintext_buf(header_size + pixels.size());
-        std::memcpy(plaintext_buf.data(), bmp_header, header_size);
-        std::memcpy(plaintext_buf.data() + header_size, pixels.data(), pixels.size());
-
-        file::write_file(plaintext_path, plaintext_buf);
+        bmp::BmpFile bmp{file::read_file(ciphertext_path)};
+        bmp.replace_pixels(box.decrypt_buffer(
+            bmp.get_pixels(),
+            bmp.get_pixels_size()));
+        file::write_file(plaintext_path, bmp.get_buffer(), bmp.get_size());
     }
 
     void decrypt_bmp(const Settings& settings)
diff --git a/utils/encrypt_bmp.cpp b/utils/encrypt_bmp.cpp
index c0fd688..c28dbf2 100644
--- a/utils/encrypt_bmp.cpp
+++ b/utils/encrypt_bmp.cpp
@@ -4,20 +4,16 @@
 // Distributed under the MIT License.
 
 #include "file_cmd_parser.hpp"
+#include "helpers/bmp.hpp"
 #include "helpers/file.hpp"
 
 #include <aesxx/all.hpp>
 
-#include <Windows.h>
-
 #include <boost/program_options.hpp>
 
-#include <cstring>
-
 #include <exception>
 #include <iostream>
 #include <string>
-#include <vector>
 
 namespace
 {
@@ -26,22 +22,11 @@ namespace
         const std::string& plaintext_path,
         const std::string& ciphertext_path)
     {
-        const auto plaintext_buf = file::read_file(plaintext_path);
-
-        const auto bmp_header = reinterpret_cast<const BITMAPFILEHEADER*>(plaintext_buf.data());
-
-        const auto header_size = bmp_header->bfOffBits;
-        const auto pixels = plaintext_buf.data() + header_size;
-        const auto pixels_size = plaintext_buf.size() - header_size;
-
-        const auto cipherpixels = box.encrypt_buffer(
-            pixels, pixels_size);
-
-        std::vector<unsigned char> ciphertext_buf(header_size + cipherpixels.size());
-        std::memcpy(ciphertext_buf.data(), bmp_header, header_size);
-        std::memcpy(ciphertext_buf.data() + header_size, cipherpixels.data(), cipherpixels.size());
-
-        file::write_file(ciphertext_path, ciphertext_buf);
+        bmp::BmpFile bmp{file::read_file(plaintext_path)};
+        bmp.replace_pixels(box.encrypt_buffer(
+            bmp.get_pixels(),
+            bmp.get_pixels_size()));
+        file::write_file(ciphertext_path, bmp.get_buffer(), bmp.get_size());
     }
 
     void encrypt_bmp(const Settings& settings)
diff --git a/utils/helpers/bmp.hpp b/utils/helpers/bmp.hpp
new file mode 100644
index 0000000..dc3cdac
--- /dev/null
+++ b/utils/helpers/bmp.hpp
@@ -0,0 +1,51 @@
+// Copyright (c) 2016 Egor Tensin <Egor.Tensin@gmail.com>
+// This file is part of the "AES tools" project.
+// For details, see https://github.com/egor-tensin/aes-tools.
+// Distributed under the MIT License.
+
+#include <Windows.h>
+
+#include <cstddef>
+#include <cstring>
+
+#include <string>
+#include <utility>
+#include <vector>
+
+namespace bmp
+{
+    class BmpFile
+    {
+    public:
+        BmpFile(std::vector<char>&& buffer)
+            : buffer{std::move(buffer)}
+            , header_size{extract_pixels_offset()}
+        { }
+
+        const void* get_buffer() const { return buffer.data(); }
+
+        std::size_t get_size() const { return buffer.size(); }
+
+        std::size_t get_header_size() const { return header_size; }
+
+        const void* get_pixels() const { return buffer.data() + get_header_size(); }
+
+        std::size_t get_pixels_size() const { return get_size() - get_header_size(); }
+
+        void replace_pixels(std::vector<unsigned char>&& pixels)
+        {
+            buffer.resize(get_header_size() + pixels.size());
+            std::memcpy(buffer.data() + get_header_size(), pixels.data(), pixels.size());
+        }
+
+    private:
+        std::size_t extract_pixels_offset() const
+        {
+            const auto header = reinterpret_cast<const BITMAPFILEHEADER*>(get_buffer());
+            return header->bfOffBits;
+        }
+
+        std::vector<char> buffer;
+        std::size_t header_size;
+    };
+}
diff --git a/utils/helpers/file.hpp b/utils/helpers/file.hpp
index a327c35..febe98f 100644
--- a/utils/helpers/file.hpp
+++ b/utils/helpers/file.hpp
@@ -3,10 +3,12 @@
 // For details, see https://github.com/egor-tensin/aes-tools.
 // Distributed under the MIT License.
 
+#include <cassert>
 #include <cstddef>
 
 #include <fstream>
 #include <iterator>
+#include <limits>
 #include <string>
 #include <vector>
 
@@ -17,7 +19,9 @@ namespace file
         std::ifstream ifs;
         ifs.exceptions(std::ifstream::badbit | std::ifstream::failbit);
         ifs.open(path, std::ifstream::binary | std::ifstream::ate);
-        return ifs.tellg();
+        const auto size = static_cast<std::streamoff>(ifs.tellg());
+        assert(size <= static_cast<std::streamoff>(std::numeric_limits<std::size_t>::max()));
+        return static_cast<std::size_t>(size);
     }
 
     inline std::vector<char> read_file(const std::string& path)
@@ -38,11 +42,19 @@ namespace file
 
     inline void write_file(
         const std::string& path,
-        const std::vector<unsigned char>& src)
+        const void* buffer,
+        const std::size_t size)
     {
         std::ofstream ofs;
         ofs.exceptions(std::ofstream::badbit | std::ofstream::failbit);
         ofs.open(path, std::ofstream::binary);
-        ofs.write(reinterpret_cast<const char*>(src.data()), src.size());
+        ofs.write(reinterpret_cast<const char*>(buffer), size);
+    }
+
+    inline void write_file(
+        const std::string& path,
+        const std::vector<unsigned char>& src)
+    {
+        write_file(path, src.data(), src.size());
     }
 }