add extract-bml action

src/BMLArchive.cc

@@ -0,0 +1,105 @@
+#include "BMLArchive.hh"
+
+#include <phosg/Encoding.hh>
+#include <phosg/Filesystem.hh>
+#include <stdexcept>
+
+#include "Text.hh"
+
+using namespace std;
+
+
+
+template <typename LongT>
+struct BMLHeader {
+  parray<uint8_t, 0x04> unknown_a1;
+  LongT num_entries;
+  parray<uint8_t, 0x38> unknown_a2;
+} __attribute__((packed));
+
+template <typename LongT>
+struct BMLHeaderEntry {
+  ptext<char, 0x20> filename;
+  LongT compressed_size;
+  parray<uint8_t, 0x04> unknown_a1;
+  LongT decompressed_size;
+  LongT compressed_gvm_size;
+  LongT decompressed_gvm_size;
+  parray<uint8_t, 0x0C> unknown_a2;
+} __attribute__((packed));
+
+template <typename LongT>
+void BMLArchive::load_t() {
+  StringReader r(*this->data);
+
+  const auto& header = r.get<BMLHeader<LongT>>();
+
+  size_t offset = 0x800;
+  while (this->entries.size() < header.num_entries) {
+    const auto& entry = r.get<BMLHeaderEntry<LongT>>();
+
+    if (offset + entry.compressed_size > this->data->size()) {
+      throw runtime_error("BML data entry extends beyond end of data");
+    }
+    size_t data_offset = offset;
+    offset = (offset + entry.compressed_size + 0x1F) & (~0x1F);
+
+    if (offset + entry.compressed_gvm_size > this->data->size()) {
+      throw runtime_error("BML GVM entry extends beyond end of data");
+    }
+    size_t gvm_offset = offset;
+    offset = (offset + entry.compressed_gvm_size + 0x1F) & (~0x1F);
+
+    this->entries.emplace(entry.filename, Entry{
+        data_offset, entry.compressed_size, gvm_offset, entry.compressed_gvm_size});
+  }
+}
+
+BMLArchive::BMLArchive(shared_ptr<const string> data, bool big_endian)
+  : data(data) {
+  if (big_endian) {
+    this->load_t<be_uint32_t>();
+  } else {
+    this->load_t<le_uint32_t>();
+  }
+}
+
+const unordered_map<string, BMLArchive::Entry> BMLArchive::all_entries() const {
+  return this->entries;
+}
+
+pair<const void*, size_t> BMLArchive::get(const std::string& name) const {
+  try {
+    const auto& entry = this->entries.at(name);
+    return make_pair(this->data->data() + entry.offset, entry.size);
+  } catch (const out_of_range&) {
+    throw out_of_range("BML does not contain file: " + name);
+  }
+}
+
+pair<const void*, size_t> BMLArchive::get_gvm(const std::string& name) const {
+  try {
+    const auto& entry = this->entries.at(name);
+    return make_pair(this->data->data() + entry.gvm_offset, entry.gvm_size);
+  } catch (const out_of_range&) {
+    throw out_of_range("BML does not contain file: " + name);
+  }
+}
+
+string BMLArchive::get_copy(const string& name) const {
+  try {
+    const auto& entry = this->entries.at(name);
+    return this->data->substr(entry.offset, entry.size);
+  } catch (const out_of_range&) {
+    throw out_of_range("BML does not contain file: " + name);
+  }
+}
+
+StringReader BMLArchive::get_reader(const string& name) const {
+  try {
+    const auto& entry = this->entries.at(name);
+    return StringReader(this->data->data() + entry.offset, entry.size);
+  } catch (const out_of_range&) {
+    throw out_of_range("BML does not contain file: " + name);
+  }
+}