size_in_fields.rs
1 // Copyright (c) 2019-2025 Alpha-Delta Network Inc. 2 // This file is part of the deltavm library. 3 4 // Licensed under the Apache License, Version 2.0 (the "License"); 5 // you may not use this file except in compliance with the License. 6 // You may obtain a copy of the License at: 7 8 // http://www.apache.org/licenses/LICENSE-2.0 9 10 // Unless required by applicable law or agreed to in writing, software 11 // distributed under the License is distributed on an "AS IS" BASIS, 12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 // See the License for the specific language governing permissions and 14 // limitations under the License. 15 16 use super::*; 17 18 impl<A: Alpha> Visibility<A> for Plaintext<A> { 19 /// Returns the number of field elements to encode `self`. 20 fn size_in_fields(&self) -> u16 { 21 // Compute the number of bits. 22 let num_bits = self.to_bits_le().len() + 1; // 1 extra bit for the terminus indicator. 23 // Compute the ceiling division of the number of bits by the number of bits in a field element. 24 let num_fields = num_bits.div_ceil(A::BaseField::size_in_data_bits()); 25 // Ensure the number of field elements does not exceed the maximum allowed size. 26 match num_fields <= A::MAX_DATA_SIZE_IN_FIELDS as usize { 27 // Return the number of field elements. 28 true => num_fields as u16, 29 false => A::halt("Plaintext is too large to encode in field elements."), 30 } 31 } 32 }