Public V0.0.1

source/lz11.cpp

@@ -0,0 +1,112 @@
+#include <cstring>
+#include <ctrff/lz11.hpp>
+
+/// REWRITTEN CODE FROM BANNERTOOL !!!!!!
+
+namespace ctrff {
+namespace LZ11 {
+PD::u32 GetOccurenceLength(const PD::u8* new_ptr, size_t new_len,
+                           const PD::u8* old_ptr, size_t old_len,
+                           PD::u32& disp) {
+  disp = 0;
+  if (new_len == 0) {
+    return 0;
+  }
+  PD::u32 res = 0;
+  if (old_len > 0) {
+    for (size_t i = 0; i < old_len - 1; i++) {
+      auto ref = old_ptr + i;
+      size_t len = 0;
+      for (size_t j = 0; j < new_len; j++) {
+        if (*(ref + j) != (*new_ptr + j)) {
+          break;
+        }
+        len++;
+      }
+      if (len > res) {
+        res = len;
+        disp = old_len - i;
+        if (res == new_len) {
+          break;
+        }
+      }
+    }
+  }
+  return res;
+}
+
+CTRFF_API std::vector<PD::u8> Compress(const std::vector<PD::u8>& in) {
+  if (in.size() > 0xFFFFFF) {
+    std::cout << "ERROR: LZ11 input is too large!" << std::endl;
+    return std::vector<PD::u8>();
+  }
+  std::stringstream s;
+  // SETUP HEADER //
+  s << static_cast<PD::u8>(0x11);
+  s << static_cast<PD::u8>(in.size() & 0xFF);
+  s << static_cast<PD::u8>((in.size() >> 8) & 0xFF);
+  s << static_cast<PD::u8>((in.size() >> 16) & 0xFF);
+
+  size_t res_len = 4;    // 4-byte header
+  PD::u8 out_buf[0x21];  // 33 bytes
+  out_buf[0] = 0;
+  size_t obl = 1;  // out_buf_len
+  size_t buf_blocks = 0;
+  size_t rb = 0;
+
+  while (rb < in.size()) {
+    if (buf_blocks == 8 || obl >= sizeof(out_buf) - 3) {
+      s.write(reinterpret_cast<const char*>(out_buf), obl);
+      res_len += obl;
+      out_buf[0] = 0;
+      obl = 1;
+      buf_blocks = 0;
+    }
+
+    PD::u32 disp = 0;
+    size_t old_len = std::min(rb, static_cast<size_t>(0x1000));
+    size_t len = LZ11::GetOccurenceLength(
+        in.data() + rb, std::min(in.size() - rb, static_cast<size_t>(0x10110)),
+        in.data() + rb - old_len, old_len, disp);
+
+    if (len < 3) {
+      out_buf[obl++] = in[rb++];
+    } else {
+      rb += len;
+      out_buf[0] |= static_cast<PD::u8>(1 << (7 - buf_blocks));
+      if (len > 0x110) {
+        out_buf[obl++] =
+            0x10 | static_cast<PD::u8>(((len - 0x111) >> 12) & 0x0F);
+        out_buf[obl++] = static_cast<PD::u8>(((len - 0x111) >> 4) & 0xFF);
+        out_buf[obl] = static_cast<PD::u8>(((len - 0x111) << 4) & 0xF0);
+      } else if (len > 0x10) {
+        out_buf[obl++] = 0x00 | static_cast<PD::u8>(((len - 0x11) >> 4) & 0x0F);
+        out_buf[obl] = static_cast<PD::u8>(((len - 0x11) << 4) & 0xF0);
+      } else {
+        out_buf[obl] |= static_cast<PD::u8>(((len - 1) << 4) & 0xF0);
+      }
+      obl++;
+      out_buf[obl++] = static_cast<PD::u8>(((disp - 1) >> 8) & 0x0F);
+      out_buf[obl++] = static_cast<PD::u8>((disp - 1) & 0xFF);
+    }
+    buf_blocks++;
+  }
+
+  if (buf_blocks > 0) {
+    s.write(reinterpret_cast<const char*>(out_buf), obl);
+    res_len += obl;
+  }
+
+  if (res_len % 4 != 0) {
+    PD::u32 pad_len = 4 - (res_len % 4);
+    PD::u8 pad[4] = {0};
+    s.write(reinterpret_cast<const char*>(pad), pad_len);
+    res_len += pad_len;
+  }
+
+  std::vector<PD::u8> res(res_len);
+  s.read(reinterpret_cast<char*>(res.data()), res.size());
+  return res;
+}
+}  // namespace LZ11
+}  // namespace ctrff