zstreambuf::~zstreambuf()
{
switch( m_state ) {
case STATE_DEFLATING:
DeflateEnd();
break;
case STATE_INFLATING:
InflateEnd();
break;
default:
break;
}
}
void Deflate(FILE *input_file, FILE *output_file) {
z_stream stream;
DeflateInit(&stream);
int flush = Z_NO_FLUSH;
int ret = Z_OK;
do {
stream.avail_in = fread(input_buf, 1, sizeof(input_buf), input_file);
if (ferror(input_file) != 0) {
ERROR("failed to read from file");
} else if (feof(input_file) != 0) {
// 入力が尽きれば deflate() の第 2 引数を Z_FINISH に切り替えます．
flush = Z_FINISH;
}
stream.next_in = input_buf;
do {
// 出力バッファを再設定して圧縮の続きをおこないます．
stream.next_out = output_buf;
stream.avail_out = sizeof(output_buf);
ret = deflate(&stream, flush);
if (ret == Z_STREAM_ERROR) {
ERROR("%s", stream.msg);
}
fwrite(output_buf, sizeof(output_buf) - stream.avail_out,
1, output_file);
if (ferror(output_file) != 0) {
ERROR("failed to write into file");
}
} while ((stream.avail_out == 0) && (ret != Z_STREAM_END));
if (stream.avail_in != 0) {
ERROR("unexpected bytes in input buffer");
}
} while (flush != Z_FINISH);
if (ret != Z_STREAM_END) {
ERROR("failed to finish deflate");
}
if (fflush(output_file) != 0) {
ERROR("failed to flush output file");
}
DeflateEnd(&stream);
}
