Adding support for compression using zlib/gzip

Abstracted all direct access to opening, closing, resetting, flushing, reading & writing files of io_buf into access through a function of io_buf which have all been declared virtual. Now that these accesses have been abstracted out, adding a new type of io_buf, in this case, comp_io_buf, is pretty easy. Just public inherit io_buf and override the default definitions of these virtual functions to work with compressed files.

There is a nuance in this because of the current use of multiple files. The 'files' v_array is conveniently typed to int. So in the comp_io_buf, I hold a v_array of gzFiles whose indices are stored in 'files' v_array.

Have introduced a new boolean flag compressed into parse_args.

The input & output io_bufs in parser are now just pointers that will point to comp_io_buf if the compressed option is chosen. This is the root cause of most of the changes involving parser::input & parser::output.

Because of the design of zlib which allows gzread to read from a normal file we can read from a mix of compressed and uncompressed files(cache) without extra logic.

1 files changed, 1 insertions, 1 deletions

diff --git a/main.cc b/main.cc
index 3419e18f..e1543419 100644
--- a/main.cc
+++ b/main.cc
@@ -29,7 +29,7 @@ int main(int argc, char *argv[]) {
 		cerr << endl;
 	}
 
-	free(vars);
+	delete vars;
 
 	return 0;
 }