main.c

/*
   LZ4 Demo program
   Main file I/O
   Copyright (C) Yann Collet 2011,

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/


//****************************
// Includes
//****************************
#include <stdio.h>     // printf, fopen, fread
#include <stdlib.h>    // malloc
#include "lz4.h"


//****************************
// Constants
//****************************
#define COMPRESSOR_NAME "LZ4 - Demo program"
#define COMPRESSOR_VERSION "v1.0"
#define COMPILED __DATE__
#define AUTHOR "Yann Collet"
#define BINARY_NAME "LZ4.exe"
#define EXTENSION ".lz4"
#define WELCOME_MESSAGE "*** %s %s, by %s (%s) ***\n", COMPRESSOR_NAME, COMPRESSOR_VERSION, AUTHOR, COMPILED

#define CHUNKSIZE (8<<20)    // 8 MB
#define CACHELINE 64
#define OUT_CHUNKSIZE (CHUNKSIZE + CHUNKSIZE/256 + CACHELINE)
#define PRIME 181
#define ARCHIVE_MAGICNUMBER 0x184C2102
#define ARCHIVE_MAGICNUMBER_SIZE 4



//****************************
// Functions
//****************************
int usage()
{
	printf("Usage :\n");
	printf("      %s [arg] input [output]\n",BINARY_NAME);
	printf("Arguments :\n");
	printf(" -c : force compression (default)\n");
	printf(" -d : force decompression \n");
	printf(" -h : help (this text)\n");	
	return 0;
}


int badusage()
{
	printf("Wrong parameters\n");
	usage();
	printf(" --- type any key to exit ---\n");
	return 0;
}


compress_file(char* input_filename, char* output_filename)
{
	long long filesize = 0;
	long long compressedfilesize = ARCHIVE_MAGICNUMBER_SIZE;
	char* in_buff;
	char* out_buff;
	FILE* finput = fopen( input_filename, "rb" ); 
	FILE* foutput = fopen( output_filename, "wb" ); 
	
	if ( finput==0 ) { printf("Pb opening %s\n", input_filename);  return 2; }
	if ( foutput==0) { printf("Pb opening %s\n", output_filename); return 3; }

	// Allocate Memory
	in_buff = malloc(CHUNKSIZE);
	out_buff = malloc(OUT_CHUNKSIZE);
	
	// Write Archive Header
	* (unsigned long*) out_buff = ARCHIVE_MAGICNUMBER;
	fwrite(out_buff, 1, ARCHIVE_MAGICNUMBER_SIZE, foutput);

	// Main Loop
	while (1) 
	{	
		int outSize;
		// Read Block
	    int inSize = fread( in_buff, 1, CHUNKSIZE, finput );
		if( inSize<=0 ) break;
		filesize += inSize;

		// Compress Block
		outSize = LZ4_compress(in_buff, out_buff+4, inSize);
		* (unsigned long*) out_buff = outSize;
		compressedfilesize += outSize;

		// Write Block
		fwrite(out_buff, 1, outSize+4, foutput);
	}

	// Status
	printf("Compressed %llu bytes into %llu bytes ==> %.2f%%\n", filesize, compressedfilesize, (double)compressedfilesize/filesize*100);

	fclose(finput);
	fclose(foutput);

	return 0;
}


decode_file(char* input_filename, char* output_filename)
{
	long long filesize = 0;
	char* in_buff;
	char* out_buff;
	FILE* finput = fopen( input_filename, "rb" ); 
	FILE* foutput = fopen( output_filename, "wb" ); 
	
	if ( finput==0 ) { printf("Pb opening %s\n", input_filename);  return 2; }
	if ( foutput==0) { printf("Pb opening %s\n", output_filename); return 3; }

	// Allocate Memory
	in_buff = malloc(OUT_CHUNKSIZE);
	out_buff = malloc(CHUNKSIZE + CACHELINE);
	
	// Check Archive Header
	fread(out_buff, 1, ARCHIVE_MAGICNUMBER_SIZE, finput);
	if (* (unsigned long*) out_buff != ARCHIVE_MAGICNUMBER) { printf("Wrong file : cannot be decoded\n"); return 4; }

	// Main Loop
	while (1) 
	{	
		int outSize;
		// Read Block
	    int inSize = fread( in_buff, 1, 4, finput );
		if( inSize<=0 ) break;
		inSize = (int) * (unsigned long*) in_buff;
	    fread( in_buff, 1, inSize, finput );

		// Decode Block
		outSize = LZ4_decode(in_buff, out_buff, inSize);
		filesize += outSize;

		// Write Block
		fwrite(out_buff, 1, outSize, foutput);
	}

	// Status
	printf("Successfully decoded %llu bytes \n", filesize);

	fclose(finput);
	fclose(foutput);

	return 0;
}


int main(int argc, char** argv) 
{
  int i,
	  compression=1,   // default action if no argument
	  decode=0;
  char *input_filename=0,
	   *output_filename=0;

  // Welcome message
  printf(WELCOME_MESSAGE);
  
  //printf("Nb argument = %i \n", argc);
  if (argc<2) { badusage(); return 1; }

  for(i=1; i<argc; i++)
  {
    char* argument = argv[i];
	char command = 0;

    if(!argument) continue;   // Protection if argument empty

	if (argument[0]=='-') command++;  // valid command trigger
	if (argument[0]=='/') command++;  // valid command trigger

	// Select command
	if (command)
	{
		argument += command;
		
		// display help on usage
		if( argument[0] =='h' )
		  { usage(); return 0; }

		// Forced Compression (default)
		if( argument[0] =='c' )
		  { compression=1; continue; }

		// Forced Decoding 
		if( argument[0] =='d' )
		  { decode=1; continue; }

	}

	// first provided filename is input
    if (!input_filename) { input_filename=argument; continue; }

	// second provided filename is output
    if (!output_filename) { output_filename=argument; continue; }
  }

  // No input filename ==> Error
  if(!input_filename) { badusage(); return 1; }

  // No output filename 
  if (!output_filename) { badusage(); return 1; }

  if (decode) return decode_file(input_filename, output_filename);

  if (compression) return compress_file(input_filename, output_filename);

  badusage(); 

  return 0;
}