DiscIO: Avoid zeroing buffer when compressing gcz.

This saves 6% time.

Source/Core/DiscIO/CompressedBlob.cpp

@@ -163,11 +163,19 @@ bool CompressFileToBlob(const std::string& infile, const std::string& outfile, u
 		scrubbing = true;
 	}
 
+	z_stream z;
+	memset(&z, 0, sizeof(z));
+	if (deflateInit(&z, 9) != Z_OK)
+		return false;
+
 	File::IOFile inf(infile, "rb");
 	File::IOFile f(outfile, "wb");
 
 	if (!f || !inf)
+	{
+		deflateEnd(&z);
 		return false;
+	}
 
 	callback("Files opened, ready to compress.", 0, arg);
 
@@ -213,23 +221,20 @@ bool CompressFileToBlob(const std::string& infile, const std::string& outfile, u
 		}
 
 		offsets[i] = position;
-		// u64 start = i * header.block_size;
-		// u64 size = header.block_size;
-		std::fill(in_buf, in_buf + header.block_size, 0);
+
+		size_t read_bytes;
 		if (scrubbing)
-			DiscScrubber::GetNextBlock(inf, in_buf);
+			read_bytes = DiscScrubber::GetNextBlock(inf, in_buf);
 		else
-			inf.ReadBytes(in_buf, header.block_size);
-		z_stream z;
-		memset(&z, 0, sizeof(z));
-		z.zalloc = Z_NULL;
-		z.zfree  = Z_NULL;
-		z.opaque = Z_NULL;
+			inf.ReadArray(in_buf, header.block_size, &read_bytes);
+		if (read_bytes < header.block_size)
+			std::fill(in_buf + read_bytes, in_buf + header.block_size, 0);
+
+		int retval = deflateReset(&z);
 		z.next_in   = in_buf;
 		z.avail_in  = header.block_size;
 		z.next_out  = out_buf;
 		z.avail_out = block_size;
-		int retval = deflateInit(&z, 9);
 
 		if (retval != Z_OK)
 		{
@@ -258,8 +263,6 @@ bool CompressFileToBlob(const std::string& infile, const std::string& outfile, u
 			position += comp_size;
 			num_compressed++;
 		}
-
-		deflateEnd(&z);
 	}
 
 	header.compressed_data_size = position;
@@ -286,6 +289,8 @@ cleanup:
 	delete[] offsets;
 	delete[] hashes;
 
+	deflateEnd(&z);
+
 	DiscScrubber::Cleanup();
 	callback("Done compressing disc image.", 1.0f, arg);
 	return true;

Source/Core/DiscIO/DiscScrubber.cpp

@@ -124,24 +124,27 @@ bool SetupScrub(const std::string& filename, int block_size)
 	return success;
 }
 
-void GetNextBlock(File::IOFile& in, u8* buffer)
+size_t GetNextBlock(File::IOFile& in, u8* buffer)
 {
 	u64 CurrentOffset = m_BlockCount * m_BlockSize;
 	u64 i = CurrentOffset / CLUSTER_SIZE;
 
+	size_t ReadBytes = 0;
 	if (m_isScrubbing && m_FreeTable[i])
 	{
 		DEBUG_LOG(DISCIO, "Freeing 0x%016" PRIx64, CurrentOffset);
 		std::fill(buffer, buffer + m_BlockSize, 0xFF);
 		in.Seek(m_BlockSize, SEEK_CUR);
+		ReadBytes = m_BlockSize;
 	}
 	else
 	{
 		DEBUG_LOG(DISCIO, "Used    0x%016" PRIx64, CurrentOffset);
-		in.ReadBytes(buffer, m_BlockSize);
+		in.ReadArray(buffer, m_BlockSize, &ReadBytes);
 	}
 
 	m_BlockCount++;
+	return ReadBytes;
 }
 
 void Cleanup()

Source/Core/DiscIO/DiscScrubber.h

@@ -25,7 +25,7 @@ namespace DiscScrubber
 {
 
 bool SetupScrub(const std::string& filename, int block_size);
-void GetNextBlock(File::IOFile& in, u8* buffer);
+size_t GetNextBlock(File::IOFile& in, u8* buffer);
 void Cleanup();
 
 } // namespace DiscScrubber