Function unzip_read_block

src/burp/mvol.cpp:426–490

//

static ULONG unzip_read_block(BurpGlobals* tdgbl, UCHAR* buffer, FB_SIZE_T buffer_length)
{
	if (!tdgbl->gbl_sw_zip)
	{
		return crypt_read_block(tdgbl, buffer, buffer_length);
	}

#ifdef HAVE_ZLIB_H
	z_stream& strm = tdgbl->gbl_stream;
	strm.avail_out = buffer_length;
	strm.next_out = buffer;

	for (;;)
	{
		if (strm.avail_in)
		{
#ifdef COMPRESS_DEBUG
			fprintf(stderr, "Data to inflate %d port %p\n", strm.avail_in, port);
#if COMPRESS_DEBUG > 1
			for (unsigned n = 0; n < strm.avail_in; ++n) fprintf(stderr, "%02x ", strm.next_in[n]);
			fprintf(stderr, "\n");
#endif
#endif
			ULONG wasAvail = strm.avail_out;
			int ret = zlib().inflate(&strm, Z_NO_FLUSH);
			if (ret == Z_DATA_ERROR && wasAvail != strm.avail_out)
				ret = Z_OK;

			if (ret != Z_OK)
			{
#ifdef COMPRESS_DEBUG
				fprintf(stderr, "Inflate error %d\n", ret);
#endif
				BURP_error(379, true, SafeArg() << ret);
			}
#ifdef COMPRESS_DEBUG
			fprintf(stderr, "Inflated data %d\n", buffer_length - strm.avail_out);
#if COMPRESS_DEBUG > 1
			for (unsigned n = 0; n < buffer_length - strm.avail_out; ++n) fprintf(stderr, "%02x ", buffer[n]);
			fprintf(stderr, "\n");
#endif
#endif
			if (strm.next_out != buffer)
				break;

			UCHAR* compressed = tdgbl->gbl_decompress;
			if (strm.next_in != compressed)
			{
				memmove(compressed, strm.next_in, strm.avail_in);
				strm.next_in = compressed;
			}
		}
		else
			strm.next_in = tdgbl->gbl_decompress;

		ULONG l = ZC_BUFSIZE - strm.avail_in;
		l = crypt_read_block(tdgbl, strm.next_in, l);
		strm.avail_in += l;