bundles/org.simantics.fastlz/native/fastlz_write.c

   1 /*******************************************************************************
   2  * Copyright (c) 2007, 2010 Association for Decentralized Information Management
   3  * in Industry THTH ry.
   4  * All rights reserved. This program and the accompanying materials
   5  * are made available under the terms of the Eclipse Public License v1.0
   6  * which accompanies this distribution, and is available at
   7  * http://www.eclipse.org/legal/epl-v10.html
   8  *
   9  * Contributors:
  10  *     VTT Technical Research Centre of Finland - initial API and implementation
  11  *******************************************************************************/
  12 #include <stdio.h>
  13 #include <stdlib.h>
  14 #include <string.h>
  15 #include "fastlz.h"
  16
  17 #define BLOCKSIZE (128*1024)
  18
  19 char* uncompressed;
  20 int uncompressedCapacity;
  21 int position;
  22 char* compressed;
  23 int compressedCapacity;
  24
  25 FILE* handle;
  26
  27 void initWrite(FILE* _handle) {
  28     uncompressedCapacity = BLOCKSIZE;
  29     uncompressed = malloc(uncompressedCapacity);
  30     position = 0;
  31     compressedCapacity = 8 + BLOCKSIZE + (BLOCKSIZE/20);
  32     compressed = malloc(compressedCapacity);
  33     handle = _handle;
  34 }
  35
  36 void flushBuffer() {
  37     int uncompressedSize = position;
  38     int compressedSize = fastlz_compress(uncompressed, uncompressedSize, compressed+8);
  39
  40     ((int*)compressed)[0] = compressedSize;
  41     ((int*)compressed)[1] = uncompressedSize;
  42
  43     fwrite(compressed, compressedSize+8, 1, handle);
  44     position = 0;
  45 }
  46
  47 void deinitWrite() {
  48     flushBuffer();
  49
  50     ((int*)compressed)[0] = 0;
  51     ((int*)compressed)[1] = 0;
  52     fwrite(compressed, 8, 1, handle);
  53
  54     free(uncompressed);
  55     uncompressed = 0;
  56     free(compressed);
  57     compressed = 0;
  58     handle = 0;
  59 }
  60
  61 void write(char* data, int offset, int length) {
  62     int s;
  63
  64     while(length > uncompressedCapacity - position) {
  65         s = uncompressedCapacity - position;
  66         memcpy(uncompressed + position, data + offset, s);
  67         offset += s;
  68         length -= s;
  69         position += s;
  70         flushBuffer();
  71     }
  72     memcpy(uncompressed + position, data + offset, length);
  73     position += length;
  74 }