Add gzip compression transform and compress command line prog.

2 files changed, 82 insertions, 3 deletions

diff --git a/src/cmd/compress.cpp b/src/cmd/compress.cpp
new file mode 100644
index 000000000..fc1ece7bd
--- /dev/null
+++ b/src/cmd/compress.cpp
@@ -0,0 +1,79 @@
+
+#include "apps.h"
+
+#include <botan/compression.h>
+#include <fstream>
+
+namespace {
+
+void do_compress(Transformation& comp, std::ifstream& in, std::ostream& out)
+   {
+   secure_vector<byte> buf;
+
+   comp.start();
+
+   while(in.good())
+      {
+      buf.resize(16*1024);
+      in.read(reinterpret_cast<char*>(&buf[0]), buf.size());
+      buf.resize(in.gcount());
+
+      comp.update(buf);
+
+      out.write(reinterpret_cast<const char*>(&buf[0]), buf.size());
+      }
+
+   buf.clear();
+   comp.finish(buf);
+   out.write(reinterpret_cast<const char*>(&buf[0]), buf.size());
+   }
+
+int compress(int argc, char* argv[])
+   {
+   const std::string in_file = argv[1];
+   std::ifstream in(in_file.c_str());
+
+   if(!in.good())
+      {
+      std::cout << "Couldn't read " << in_file << "\n";
+      return 1;
+      }
+
+   const size_t level = 6;
+   const std::string suffix = "gz";
+
+   std::unique_ptr<Transformation> compress(make_compressor(suffix, level));
+
+   const std::string out_file = in_file + "." + suffix;
+   std::ofstream out(out_file.c_str());
+
+   do_compress(*compress, in, out);
+
+   return 0;
+   }
+
+int uncompress(int argc, char* argv[])
+   {
+   const std::string in_file = argv[1];
+   std::ifstream in(in_file.c_str());
+
+   if(!in.good())
+      {
+      std::cout << "Couldn't read " << argv[1] << "\n";
+      return 1;
+      }
+
+   std::ofstream out("out");
+   const std::string suffix = "gz";
+
+   std::unique_ptr<Transformation> decompress(make_decompressor(suffix));
+
+   do_compress(*decompress, in, out);
+
+   return 0;
+   }
+
+REGISTER_APP(compress);
+REGISTER_APP(uncompress);
+
+}
diff --git a/src/cmd/main.cpp b/src/cmd/main.cpp
index 65530b23a..42acf99e7 100644
--- a/src/cmd/main.cpp
+++ b/src/cmd/main.cpp
@@ -170,17 +170,17 @@ int main(int argc, char* argv[])
       if(apps.has(cmd))
          return apps.run(cmd, argc - 1, argv + 1);
 
-      std::cout << "Unknown command " << cmd << "\n";
+      std::cerr << "Unknown command " << cmd << std::endl;
       return help(argc, argv);
       }
    catch(std::exception& e)
       {
-      std::cerr << "Exception: " << e.what() << std::endl;
+      std::cerr << e.what() << std::endl;
       return 1;
       }
    catch(...)
       {
-      std::cerr << "Unknown (...) exception caught" << std::endl;
+      std::cerr << "Unknown exception caught" << std::endl;
       return 1;
       }