1 files changed, 135 insertions, 0 deletions
diff --git a/lm/builder/print.cc b/lm/builder/print.cc
new file mode 100644
index 000000000..b0323221a
--- /dev/null
+++ b/lm/builder/print.cc
@@ -0,0 +1,135 @@
+#include "lm/builder/print.hh"
+
+#include "util/double-conversion/double-conversion.h"
+#include "util/double-conversion/utils.h"
+#include "util/file.hh"
+#include "util/mmap.hh"
+#include "util/scoped.hh"
+#include "util/stream/timer.hh"
+
+#define BOOST_LEXICAL_CAST_ASSUME_C_LOCALE
+#include <boost/lexical_cast.hpp>
+
+#include <sstream>
+
+#include <string.h>
+
+namespace lm { namespace builder {
+
+VocabReconstitute::VocabReconstitute(int fd) {
+  uint64_t size = util::SizeOrThrow(fd);
+  util::MapRead(util::POPULATE_OR_READ, fd, 0, size, memory_);
+  const char *const start = static_cast<const char*>(memory_.get());
+  const char *i;
+  for (i = start; i != start + size; i += strlen(i) + 1) {
+    map_.push_back(i);
+  }
+  // Last one for LookupPiece.
+  map_.push_back(i);
+}
+
+namespace {
+class OutputManager {
+  public:
+    static const std::size_t kOutBuf = 1048576;
+
+    // Does not take ownership of out.
+    explicit OutputManager(int out)
+      : buf_(util::MallocOrThrow(kOutBuf)),
+        builder_(static_cast<char*>(buf_.get()), kOutBuf),
+        // Mostly the default but with inf instead.  And no flags.
+        convert_(double_conversion::DoubleToStringConverter::NO_FLAGS, "inf", "NaN", 'e', -6, 21, 6, 0),
+        fd_(out) {}
+
+    ~OutputManager() {
+      Flush();
+    }
+
+    OutputManager &operator<<(float value) {
+      // Odd, but this is the largest number found in the comments.
+      EnsureRemaining(double_conversion::DoubleToStringConverter::kMaxPrecisionDigits + 8);
+      convert_.ToShortestSingle(value, &builder_);
+      return *this;
+    }
+
+    OutputManager &operator<<(StringPiece str) {
+      if (str.size() > kOutBuf) {
+        Flush();
+        util::WriteOrThrow(fd_, str.data(), str.size());
+      } else {
+        EnsureRemaining(str.size());
+        builder_.AddSubstring(str.data(), str.size());
+      }
+      return *this;
+    }
+
+    // Inefficient!
+    OutputManager &operator<<(unsigned val) {
+      return *this << boost::lexical_cast<std::string>(val);
+    }
+
+    OutputManager &operator<<(char c) {
+      EnsureRemaining(1);
+      builder_.AddCharacter(c);
+      return *this;
+    }
+
+    void Flush() {
+      util::WriteOrThrow(fd_, buf_.get(), builder_.position());
+      builder_.Reset();
+    }
+
+  private:
+    void EnsureRemaining(std::size_t amount) {
+      if (static_cast<std::size_t>(builder_.size() - builder_.position()) < amount) {
+        Flush();
+      }
+    }
+
+    util::scoped_malloc buf_;
+    double_conversion::StringBuilder builder_;
+    double_conversion::DoubleToStringConverter convert_;
+    int fd_;
+};
+} // namespace
+
+PrintARPA::PrintARPA(const VocabReconstitute &vocab, const std::vector<uint64_t> &counts, const HeaderInfo* header_info, int out_fd) 
+  : vocab_(vocab), out_fd_(out_fd) {
+  std::stringstream stream;
+
+  if (header_info) {
+    stream << "# Input file: " << header_info->input_file << '\n';
+    stream << "# Token count: " << header_info->token_count << '\n';
+    stream << "# Smoothing: Modified Kneser-Ney" << '\n';
+  }
+  stream << "\\data\\\n";
+  for (size_t i = 0; i < counts.size(); ++i) {
+    stream << "ngram " << (i+1) << '=' << counts[i] << '\n';
+  }
+  stream << '\n';
+  std::string as_string(stream.str());
+  util::WriteOrThrow(out_fd, as_string.data(), as_string.size());
+}
+
+void PrintARPA::Run(const ChainPositions &positions) {
+  UTIL_TIMER("(%w s) Wrote ARPA file\n");
+  OutputManager out(out_fd_);
+  for (unsigned order = 1; order <= positions.size(); ++order) {
+    out << "\\" << order << "-grams:" << '\n';
+    for (NGramStream stream(positions[order - 1]); stream; ++stream) {
+      // Correcting for numerical precision issues.  Take that IRST.  
+      out << std::min(0.0f, stream->Value().complete.prob) << '\t' << vocab_.Lookup(*stream->begin());
+      for (const WordIndex *i = stream->begin() + 1; i != stream->end(); ++i) {
+        out << ' ' << vocab_.Lookup(*i);
+      }
+      float backoff = stream->Value().complete.backoff;
+      if (backoff != 0.0)
+        out << '\t' << backoff;
+      out << '\n';
+    }
+    out << '\n';
+  }
+  out << "\\end\\\n";
+}
+
+}} // namespaces