Bug identified, first char of new chunk not witten (see uncompress.cc:59)

src/bitpack.cc

@@ -48,9 +48,6 @@ vuchar pack(const vuint16 &t_input) {
 vuchar pack_n(const vuint16::const_iterator t_input_begin,
               const vuint16::const_iterator t_input_end, vuchar &t_res,
               int t_n) {
-#ifdef Debug
-  std::printf("%d bits!\n", t_n);
-#endif // Debug
   if (t_n == 16) {
     return pack_16(t_input_begin, t_input_end, t_res);
   }

src/compress.cc

@@ -37,30 +37,18 @@ ustring read_file(const string &filename) {
   return res;
 }
 
-/**
- *  La chaîne de caractères \p t_text est lue caractère par caractère, et est
- * selon la valeur de retour de la fonction \ref dico (permettant dans le même
- * temps la création du dictionnaire), on rajoute ou non un nouveau caractère
- * encodé sur 12bits dans le chunk courant. Dès que le dictionnaire est plein
- * (2^12 caractères), le chunk est sauvegardé et vidé, et le dictionnaire est
- * réinitialisé.
- *
- *  \param t_text Chaîne de caractères uint8_t représentant le fichier d'entrée
- *  \return Vecteur de chunks (vecteurs de uint16_t)
- */
 vvuint16 lzw_compress(ustring &&t_text) {
-  std::puts("Compressing...");
-  const auto DICT_MAX = static_cast<size_t>(ipow(2, 17) - 256); /* 16 bits */
+  vvuint16 res{};
+  const auto DICT_MAX = static_cast<size_t>(ipow(2, 14) - 256); /* 16 bits */
   uint16_t w = 0xFFFF;
   vuint16 chunk{};
-  vvuint16 res{};
   dict_t dict{};
   for (const auto c : t_text) {
     if (dict.size() >= DICT_MAX) {
-      res.push_back(std::move(chunk));
-      chunk = vuint16{};
-      dict = dict_t{};
+      res.push_back(chunk);
       w = 0xFFFF;
+      chunk.clear();
+      dict.clear();
     }
     if (const auto &[exists, pos] = dico(dict, w, static_cast<uint8_t>(c));
         exists) {
@@ -88,7 +76,7 @@ vvuint16 lzw_compress(ustring &&t_text) {
  */
 void compress(const std::string &t_in_file, const char *t_out_file) {
   std::ofstream out{(t_out_file != nullptr) ? t_out_file : "output.lzw",
-                    std::ios::out | std::ios::binary};
+                    ios::out | ios::binary};
   if (!out.is_open()) {
     std::cerr << "Error at " << __FILE__ << ":" << __LINE__ - 4
               << ": could not open output file. Aborting...\n";

src/io.cc

@@ -48,9 +48,6 @@ void write_file(std::ofstream &t_out, const vvuint16 &t_chunks) {
  *  \param t_chunk Chunk to be written to \p t_out
  */
 void write_chunk(std::ofstream &t_out, const vuint16 &t_chunk) {
-#ifdef Debug
-  std::printf("Chunk!\n");
-#endif
   const auto output = pack(t_chunk);
   const auto chunk_size = static_cast<uint32_t>(output.size());
   t_out.write(reinterpret_cast<const char *>(&chunk_size), sizeof(chunk_size));

src/uncompress.cc

@@ -20,16 +20,11 @@ ustring lzw_uncompress(vuint16 &&t_compressed) {
   ustring ret{};
   uint16_t old = 0;
   std::map<uint16_t, ustring> dict{};
-  // uint16_t v = t_compressed[0];
-  // ret.append({static_cast<unsigned char>(v)});
-  // old = v;
   ret.append({static_cast<unsigned char>(t_compressed[0])});
   old = t_compressed[0];
   for (auto it = t_compressed.begin() + 1; it != t_compressed.end(); ++it) {
-    // v = *it;
     const auto uncompressed{dico_uncompress(dict, *it, old)};
     ret.insert(ret.end(), uncompressed.begin(), uncompressed.end());
-    // old = v;
     old = *it;
   }
 
@@ -39,28 +34,30 @@ ustring lzw_uncompress(vuint16 &&t_compressed) {
 void uncompress(const string &t_input_name, const char *t_output_name) {
   FILE *const input = std::fopen(t_input_name.c_str(), "rb");
   assert(input);
-  FILE *const output =
-      (t_output_name != nullptr)
-          ? std::fopen(t_output_name, "wb")
-          : std::fopen((t_input_name + "_uncompressed").c_str(), "wb");
-  assert(output);
+  std::ofstream output{(t_output_name != nullptr)
+                           ? t_output_name
+                           : t_input_name + "_uncompressed",
+                       std::ios::out | std::ios::binary | std::ios::app};
+  assert(output.is_open());
   uint16_t nb_chunks = 0;
   std::fread(&nb_chunks, sizeof(nb_chunks), 1, input);
   for (uint16_t i = 0; i < nb_chunks; ++i) {
     uncompress_chunk(input, output);
   }
-  std::fclose(output);
+  output.close();
   std::fclose(input);
 }
 
-void uncompress_chunk(FILE *const input, FILE *const output) {
+void uncompress_chunk(FILE *const t_input, std::ofstream &t_output) {
   uint32_t size_chunk = 0;
-  fread(&size_chunk, sizeof(size_chunk), 1, input);
-  auto chunk = new unsigned char[size_chunk];
-  fread(chunk, sizeof(unsigned char), size_chunk, input);
-  auto unpacked = unpack(ustring{chunk, chunk + size_chunk});
-  delete[] chunk;
-  const auto uncompressed_chunk = lzw_uncompress(std::move(unpacked));
-  std::fwrite(uncompressed_chunk.data(), sizeof(uncompressed_chunk[0]),
-              uncompressed_chunk.size(), output);
+  fread(&size_chunk, sizeof(size_chunk), 1, t_input);
+  auto chunk = std::make_unique<unsigned char[]>(size_chunk);
+  fread(chunk.get(), sizeof(unsigned char), size_chunk, t_input);
+  auto unpacked = unpack(ustring{chunk.get(), chunk.get() + size_chunk});
+  auto uncompressed_chunk = lzw_uncompress(std::move(unpacked));
+
+  // attention here for bug ///////////////////////////////////////////////////
+  uncompressed_chunk.push_back(0xFF);
+  t_output.write(reinterpret_cast<const char *>(uncompressed_chunk.data()),
+                 sizeof(uncompressed_chunk[0]) * uncompressed_chunk.size());
 }

src/uncompress.hh

@@ -1,6 +1,7 @@
 #ifndef LZW_SRC_UNCOMPRESS_H_
 #define LZW_SRC_UNCOMPRESS_H_
 
+#include <fstream>
 #include <memory>
 #include <string>
 #include <vector>
@@ -9,6 +10,6 @@ std::basic_string<unsigned char> lzw_uncompress(std::vector<std::uint16_t> &&);
 
 void uncompress(const std::string &, const char *);
 
-void uncompress_chunk(FILE *, FILE *);
+void uncompress_chunk(FILE *, std::ofstream&);
 
 #endif /* LZW_SRC_UNCOMPRESS_H_ */