1 files changed, 106 insertions, 0 deletions
diff --git a/utils/filelib.h b/utils/filelib.h
new file mode 100644
index 00000000..b9fef9a7
--- /dev/null
+++ b/utils/filelib.h
@@ -0,0 +1,106 @@
+#ifndef _FILELIB_H_
+#define _FILELIB_H_
+
+#include <cassert>
+#include <string>
+#include <iostream>
+#include <cstdlib>
+#include <boost/shared_ptr.hpp>
+#include <stdexcept>
+#include "gzstream.h"
+#include "null_deleter.h"
+
+bool FileExists(const std::string& file_name);
+bool DirectoryExists(const std::string& dir_name);
+
+// reads from standard in if filename is -
+// uncompresses if file ends with .gz
+// otherwise, reads from a normal file
+
+template <class Stream>
+struct BaseFile {
+  typedef Stream S;
+  typedef boost::shared_ptr<Stream> PS;
+  void Reset() {
+    ps_.reset();
+  }
+  bool is_null() const { return !ps_; }
+  operator bool() const {
+    return ps_;
+  }
+  S* stream() { return ps_.get(); }
+  S* operator->() { return ps_.get(); } // compat with old ReadFile * -> new Readfile. remove?
+  S &operator *() const { return get(); }
+  S &get() const { return *ps_; }
+  bool is_std() {
+    return filename_=="-";
+  }
+  std::string filename_;
+protected:
+  void error(std::string const& reason,std::string const& filename) {
+    throw std::runtime_error("File "+filename+" - "+reason);
+  }
+
+  PS ps_;
+  static bool EndsWith(const std::string& f, const std::string& suf) {
+    return (f.size() > suf.size()) && (f.rfind(suf) == f.size() - suf.size());
+  }
+};
+
+class ReadFile : public BaseFile<std::istream> {
+ public:
+  ReadFile() {  }
+  explicit ReadFile(const std::string& filename) {
+    Init(filename);
+  }
+  void Init(const std::string& filename) {
+    filename_=filename;
+    if (is_std()) {
+      ps_=PS(&std::cin,null_deleter());
+    } else {
+      if (!FileExists(filename)) {
+        std::cerr << "File does not exist: " << filename << std::endl;
+        error(filename," couldn't read nonexistant file.");
+        abort();
+      }
+      char const* file=filename_.c_str(); // just in case the gzstream keeps using the filename for longer than the constructor, e.g. inflateReset2.  warning in valgrind that I'm hoping will disappear - it makes no sense.
+      ps_=PS(EndsWith(filename, ".gz") ?
+                static_cast<std::istream*>(new igzstream(file)) :
+             static_cast<std::istream*>(new std::ifstream(file)));
+      if (!*ps_) {
+        std::cerr << "Failed to open " << filename << std::endl;
+        error(filename," open for reading failed.");
+        abort();
+      }
+    }
+  }
+
+};
+
+class WriteFile : public BaseFile<std::ostream> {
+ public:
+  WriteFile() {}
+  explicit WriteFile(std::string const& filename) { Init(filename); }
+  void Init(const std::string& filename) {
+    filename_=filename;
+    if (is_std()) {
+      ps_=PS(&std::cout,null_deleter());
+    } else {
+      char const* file=filename_.c_str(); // just in case the gzstream keeps using the filename for longer than the constructor, e.g. inflateReset2.  warning in valgrind that I'm hoping will disappear - it makes no sense.
+      ps_=PS(EndsWith(filename, ".gz") ?
+                static_cast<std::ostream*>(new ogzstream(file)) :
+                static_cast<std::ostream*>(new std::ofstream(file)));
+      if (!*ps_) {
+        std::cerr << "Failed to open " << filename << std::endl;
+        error(filename," open for writing failed.");
+        abort();
+      }
+    }
+  }
+  ~WriteFile() {
+    if (ps_)
+      get() << std::flush;
+  }
+};
+
+#endif