reifydb_codec/primitive/
decimal.rs

1// SPDX-License-Identifier: Apache-2.0
2// Copyright (c) 2026 ReifyDB
3
4use bigdecimal::BigDecimal as StdBigDecimal;
5use num_bigint::BigInt as StdBigInt;
6use reifydb_value::{
7	reifydb_assertions,
8	value::{decimal::Decimal, value_type::ValueType},
9};
10
11use crate::row::{bytes::RowBuilder, shape::RowShape};
12
13#[cfg(reifydb_assertions)]
14const MODE_DYNAMIC: u128 = 0x80000000000000000000000000000000;
15#[cfg(reifydb_assertions)]
16const MODE_MASK: u128 = 0x80000000000000000000000000000000;
17
18const DYNAMIC_OFFSET_MASK: u128 = 0x0000000000000000FFFFFFFFFFFFFFFF;
19const DYNAMIC_LENGTH_MASK: u128 = 0x7FFFFFFFFFFFFFFF0000000000000000;
20
21impl RowShape {
22	pub fn set_decimal(&self, row: &mut impl RowBuilder, index: usize, value: &Decimal) {
23		reifydb_assertions! {
24			assert!(
25				row.len() >= self.total_static_size(),
26				"row/shape size mismatch: row.len()={} < total_static_size()={}",
27				row.len(),
28				self.total_static_size()
29			);
30			assert_eq!(*self.fields()[index].constraint.get_type().inner_type(), ValueType::Decimal);
31		}
32
33		let (mantissa, original_scale) = value.inner().as_bigint_and_exponent();
34		let scale_bytes = original_scale.to_le_bytes();
35		let digits_bytes = mantissa.to_signed_bytes_le();
36
37		let mut serialized = Vec::with_capacity(8 + digits_bytes.len());
38		serialized.extend_from_slice(&scale_bytes);
39		serialized.extend_from_slice(&digits_bytes);
40
41		self.replace_dynamic_data(row, index, &serialized);
42	}
43
44	pub fn get_decimal(&self, row: &[u8], index: usize) -> Decimal {
45		let field = &self.fields()[index];
46		reifydb_assertions! {
47			assert!(
48				row.len() >= self.total_static_size(),
49				"row/shape size mismatch: row.len()={} < total_static_size()={}",
50				row.len(),
51				self.total_static_size()
52			);
53			assert_eq!(*field.constraint.get_type().inner_type(), ValueType::Decimal);
54		}
55
56		// SAFETY: row.len() >= total_static_size() puts the 16-byte slot at field.offset inside the row,
57		// read_unaligned needs no alignment, and u128 has no invalid bit patterns.
58		let packed = unsafe { (row.as_ptr().add(field.offset as usize) as *const u128).read_unaligned() };
59		let packed = u128::from_le(packed);
60
61		reifydb_assertions! {
62			assert!(packed & MODE_MASK == MODE_DYNAMIC, "Expected dynamic storage");
63		}
64
65		let offset = (packed & DYNAMIC_OFFSET_MASK) as usize;
66		let length = ((packed & DYNAMIC_LENGTH_MASK) >> 64) as usize;
67
68		let dynamic_start = self.dynamic_section_start();
69		let data_bytes = &row[dynamic_start + offset..dynamic_start + offset + length];
70
71		let original_scale = i64::from_le_bytes(data_bytes[0..8].try_into().unwrap());
72		let mantissa = StdBigInt::from_signed_bytes_le(&data_bytes[8..]);
73
74		let big_decimal = StdBigDecimal::new(mantissa, original_scale);
75
76		Decimal::from(big_decimal)
77	}
78
79	pub fn try_get_decimal(&self, row: &[u8], index: usize) -> Option<Decimal> {
80		if self.is_defined(row, index)
81			&& matches!(self.fields()[index].constraint.get_type().inner_type(), ValueType::Decimal)
82		{
83			Some(self.get_decimal(row, index))
84		} else {
85			None
86		}
87	}
88}
reifydb_codec/primitive/decimal.rs

reifydb_codec/primitive/
decimal.rs
