Optimize data flushing for `FileAccessCompressed` and `FileAccessEncrypted`

core/io/file_access_compressed.cpp

@@ -130,34 +130,37 @@ void FileAccessCompressed::_close() {
 			f->store_32(0); //compressed sizes, will update later
 		}
 
-		Vector<int> block_sizes;
+		uint32_t last_block_size = write_max % block_size;
+
+		// Temporary buffer for compressed data blocks.
+		LocalVector<uint8_t> temp_cblock;
+		temp_cblock.resize(Compression::get_max_compressed_buffer_size(bc == 1 ? last_block_size : block_size, cmode));
+		uint8_t *temp_cblock_ptr = temp_cblock.ptr();
+
+		// Compress and store the blocks.
+		LocalVector<uint32_t> block_sizes;
 		for (uint32_t i = 0; i < bc; i++) {
-			uint32_t bl = i == (bc - 1) ? write_max % block_size : block_size;
+			uint32_t bl = i == (bc - 1) ? last_block_size : block_size;
 			uint8_t *bp = &write_ptr[i * block_size];
 
-			Vector<uint8_t> cblock;
-			cblock.resize(Compression::get_max_compressed_buffer_size(bl, cmode));
-			const int64_t compressed_size = Compression::compress(cblock.ptrw(), bp, bl, cmode);
+			const int64_t compressed_size = Compression::compress(temp_cblock_ptr, bp, bl, cmode);
 			ERR_FAIL_COND_MSG(compressed_size < 0, "FileAccessCompressed: Error compressing data.");
 
-			f->store_buffer(cblock.ptr(), (uint64_t)compressed_size);
+			f->store_buffer(temp_cblock_ptr, (uint64_t)compressed_size);
 			block_sizes.push_back(compressed_size);
 		}
 
 		f->seek(16); //ok write block sizes
 		for (uint32_t i = 0; i < bc; i++) {
-			f->store_32(uint32_t(block_sizes[i]));
+			f->store_32(block_sizes[i]);
 		}
 		f->seek_end();
 		f->store_buffer((const uint8_t *)mgc.get_data(), mgc.length()); //magic at the end too
-
-		buffer.clear();
-
 	} else {
 		comp_buffer.clear();
-		buffer.clear();
 		read_blocks.clear();
 	}
+	buffer.clear();
 	f.unref();
 }
 

core/io/file_access_encrypted.cpp

@@ -140,7 +140,7 @@ void FileAccessEncrypted::_close() {
 	}
 
 	if (writing) {
-		Vector<uint8_t> compressed;
+		LocalVector<uint8_t> compressed;
 		uint64_t len = data.size();
 		if (len % 16) {
 			len += 16 - (len % 16);
@@ -150,10 +150,8 @@ void FileAccessEncrypted::_close() {
 		ERR_FAIL_COND(CryptoCore::md5(data.ptr(), data.size(), hash) != OK); // Bug?
 
 		compressed.resize(len);
-		memset(compressed.ptrw(), 0, len);
-		for (int i = 0; i < data.size(); i++) {
-			compressed.write[i] = data[i];
-		}
+		memcpy(compressed.ptr(), data.ptr(), data.size());
+		memset(compressed.ptr() + data.size(), 0, len - data.size());
 
 		CryptoCore::AESContext ctx;
 		ctx.set_encode_key(key.ptrw(), 256);
@@ -166,7 +164,7 @@ void FileAccessEncrypted::_close() {
 		file->store_64(data.size());
 		file->store_buffer(iv.ptr(), 16);
 
-		ctx.encrypt_cfb(len, iv.ptrw(), compressed.ptrw(), compressed.ptrw());
+		ctx.encrypt_cfb(len, iv.ptrw(), compressed.ptr(), compressed.ptr());
 
 		file->store_buffer(compressed.ptr(), compressed.size());
 		data.clear();