Module: LZO

Defined in:
ext/lzoruby.c

Defined Under Namespace

Classes: Error

Constant Summary collapse

VERSION = 
rb_str_new2(VERSION)
LZO_VERSION = 
rb_str_new2(lzo_version_string())

Class Method Summary collapse

Class Method Details

.adler32(v_adler, v_buf) ⇒ Object 



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# File 'ext/lzoruby.c', line 119

static VALUE lzoruby_adler32(VALUE self, VALUE v_adler, VALUE v_buf) {
  lzo_uint32 adler;
  lzo_bytep buf;
  lzo_uint len;

  Check_Type(v_adler, T_FIXNUM);
  Check_Type(v_buf, T_STRING);
  adler = FIX2LONG(v_adler);
  buf = RSTRING_PTR(v_buf);
  len = RSTRING_LEN(v_buf);

  adler = lzo_adler32(adler, buf, len);

  return LONG2FIX(adler);
}

.compress(*args) ⇒ Object 



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# File 'ext/lzoruby.c', line 30

static VALUE lzoruby_compress(int argc, const VALUE *argv, VALUE self) {
  const lzo_bytep in;
  lzo_bytep out;
  lzo_voidp wrkmem = NULL;
  lzo_uint in_len;
  lzo_uint out_len;
  lzo_uint new_len;
  VALUE v_in, v_out, v_level;
  int level, err;

  rb_scan_args(argc, argv, "11", &v_in, &v_level);
  Check_Type(v_in, T_STRING);
  level = NIL_P(v_level) ? 1 : NUM2INT(v_level);

  in = RSTRING_PTR(v_in);
  in_len = RSTRING_LEN(v_in);
  out_len = in_len + in_len / 64 + 16 + 3;
  out = xmalloc(5 + out_len);
  new_len = out_len;
  wrkmem = xmalloc((level == 1) ? LZO1X_1_MEM_COMPRESS : LZO1X_999_MEM_COMPRESS);

  if (level == 1) {
    out[0] = 0xf0;
    err = lzo1x_1_compress(in, in_len, out + 5, &new_len, wrkmem);
  } else {
    out[0] = 0xf1;
    err = lzo1x_999_compress(in, in_len, out + 5, &new_len, wrkmem);
  }

  xfree(wrkmem);

  if (err != LZO_E_OK || new_len > out_len) {
    xfree(out);
    rb_raise(LZO_Error, "Error %d while compressing data", err);
  }

  out[1] = (unsigned char) ((in_len >> 24) & 0xff);
  out[2] = (unsigned char) ((in_len >> 16) & 0xff);
  out[3] = (unsigned char) ((in_len >>  8) & 0xff);
  out[4] = (unsigned char) ((in_len >>  0) & 0xff);
  v_out = rb_str_new(out, 5 + new_len);
  xfree(out);

  return v_out;
}

.decompress(v_in) ⇒ Object 



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# File 'ext/lzoruby.c', line 77

static VALUE lzoruby_decompress(VALUE self, VALUE v_in) {
  lzo_bytep in;
  lzo_bytep out;
  lzo_uint in_len;
  lzo_uint out_len;
  lzo_uint new_len;
  VALUE v_out;
  int err;

  Check_Type(v_in, T_STRING);

  in = RSTRING_PTR(v_in);
  in_len = RSTRING_LEN(v_in);

  if (((int) in_len) < 5 + 3 || in[0] < 0xf0 || in[0] > 0xf1) {
    rb_raise(LZO_Error, "Header error - invalid compressed data");
  }

  in_len -= 5;
  out_len = (in[1] << 24) | (in[2] << 16) | (in[3] << 8) | in[4];

  if (((int) out_len) < 0 || in_len > out_len + out_len / 64 + 16 + 3) {
    rb_raise(LZO_Error, "Header error - invalid compressed data");
  }

  out = xmalloc(out_len);
  new_len = out_len;

  err = lzo1x_decompress_safe(in + 5, in_len, out, &new_len, NULL);

  if (err != LZO_E_OK || new_len != out_len) {
    xfree(out);
    rb_raise(LZO_Error, "Compressed data violation %d", err);
  }

  v_out = rb_str_new(out, new_len);
  xfree(out);

  return v_out;
}