Add fees to tx-wide caps (#22081)

sdk/src/fee.rs

@@ -0,0 +1,67 @@
+use crate::native_token::sol_to_lamports;
+
+/// A fee and its associated compute unit limit
+#[derive(Debug, Default, Clone)]
+pub struct FeeBin {
+    /// maximum compute units for which this fee will be charged
+    pub limit: u64,
+    /// fee in lamports
+    pub fee: u64,
+}
+
+/// Information used to calculate fees
+#[derive(Debug, Clone)]
+pub struct FeeStructure {
+    /// lamports per signature
+    pub lamports_per_signature: u64,
+    /// lamports_per_write_lock
+    pub lamports_per_write_lock: u64,
+    /// Compute unit fee bins
+    pub compute_fee_bins: Vec<FeeBin>,
+}
+
+impl FeeStructure {
+    pub fn new(
+        sol_per_signature: f64,
+        sol_per_write_lock: f64,
+        compute_fee_bins: Vec<(u64, f64)>,
+    ) -> Self {
+        let compute_fee_bins = compute_fee_bins
+            .iter()
+            .map(|(limit, sol)| FeeBin {
+                limit: *limit,
+                fee: sol_to_lamports(*sol),
+            })
+            .collect::<Vec<_>>();
+        FeeStructure {
+            lamports_per_signature: sol_to_lamports(sol_per_signature),
+            lamports_per_write_lock: sol_to_lamports(sol_per_write_lock),
+            compute_fee_bins,
+        }
+    }
+
+    pub fn get_max_fee(&self, num_signatures: u64, num_write_locks: u64) -> u64 {
+        num_signatures
+            .saturating_mul(self.lamports_per_signature)
+            .saturating_add(num_write_locks.saturating_mul(self.lamports_per_write_lock))
+            .saturating_add(
+                self.compute_fee_bins
+                    .last()
+                    .map(|bin| bin.fee)
+                    .unwrap_or_default(),
+            )
+    }
+}
+
+impl Default for FeeStructure {
+    fn default() -> Self {
+        Self::new(0.000005, 0.0, vec![(1_400_000, 0.0)])
+    }
+}
+
+#[cfg(RUSTC_WITH_SPECIALIZATION)]
+impl ::solana_frozen_abi::abi_example::AbiExample for FeeStructure {
+    fn example() -> Self {
+        FeeStructure::default()
+    }
+}