Use sol_get_sysvar instead of sol_get_<NAME>_sysvar

define-syscall/src/definitions.rs

@@ -33,12 +33,12 @@ define_syscall!(fn sol_get_sysvar(sysvar_id_addr: *const u8, result: *mut u8, of
 define_syscall!(fn sol_get_epoch_stake(vote_address: *const u8) -> u64);
 define_syscall!(fn sol_panic_(filename: *const u8, filename_len: u64, line: u64, column: u64));
 
-// these are to be deprecated once they are superceded by sol_get_sysvar
-define_syscall!(fn sol_get_clock_sysvar(addr: *mut u8) -> u64);
-define_syscall!(fn sol_get_epoch_schedule_sysvar(addr: *mut u8) -> u64);
-define_syscall!(fn sol_get_rent_sysvar(addr: *mut u8) -> u64);
-define_syscall!(fn sol_get_last_restart_slot(addr: *mut u8) -> u64);
-define_syscall!(fn sol_get_epoch_rewards_sysvar(addr: *mut u8) -> u64);
+// these are deprecated - use sol_get_sysvar instead
+define_syscall!(#[deprecated(since = "3.0.0", note = "Use `sol_get_sysvar` with `Clock` sysvar address instead")] fn sol_get_clock_sysvar(addr: *mut u8) -> u64);
+define_syscall!(#[deprecated(since = "3.0.0", note = "Use `sol_get_sysvar` with `EpochSchedule` sysvar address instead")] fn sol_get_epoch_schedule_sysvar(addr: *mut u8) -> u64);
+define_syscall!(#[deprecated(since = "3.0.0", note = "Use `sol_get_sysvar` with `Rent` sysvar address instead")] fn sol_get_rent_sysvar(addr: *mut u8) -> u64);
+define_syscall!(#[deprecated(since = "3.0.0", note = "Use `sol_get_sysvar` with `LastRestartSlot` sysvar address instead")] fn sol_get_last_restart_slot(addr: *mut u8) -> u64);
+define_syscall!(#[deprecated(since = "3.0.0", note = "Use `sol_get_sysvar` with `EpochRewards` sysvar address instead")] fn sol_get_epoch_rewards_sysvar(addr: *mut u8) -> u64);
 
 // this cannot go through sol_get_sysvar but can be removed once no longer in use
 define_syscall!(fn sol_get_fees_sysvar(addr: *mut u8) -> u64);

define-syscall/src/lib.rs

@@ -5,7 +5,8 @@ pub mod definitions;
 #[cfg(target_feature = "static-syscalls")]
 #[macro_export]
 macro_rules! define_syscall {
-    (fn $name:ident($($arg:ident: $typ:ty),*) -> $ret:ty) => {
+    ($(#[$attr:meta])* fn $name:ident($($arg:ident: $typ:ty),*) -> $ret:ty) => {
+        $(#[$attr])*
         #[inline]
         pub unsafe fn $name($($arg: $typ),*) -> $ret {
             // this enum is used to force the hash to be computed in a const context
@@ -19,21 +20,22 @@ macro_rules! define_syscall {
         }
 
     };
-    (fn $name:ident($($arg:ident: $typ:ty),*)) => {
-        define_syscall!(fn $name($($arg: $typ),*) -> ());
+    ($(#[$attr:meta])* fn $name:ident($($arg:ident: $typ:ty),*)) => {
+        define_syscall!($(#[$attr])* fn $name($($arg: $typ),*) -> ());
     }
 }
 
 #[cfg(not(target_feature = "static-syscalls"))]
 #[macro_export]
 macro_rules! define_syscall {
-    (fn $name:ident($($arg:ident: $typ:ty),*) -> $ret:ty) => {
+    ($(#[$attr:meta])* fn $name:ident($($arg:ident: $typ:ty),*) -> $ret:ty) => {
         extern "C" {
+            $(#[$attr])*
             pub fn $name($($arg: $typ),*) -> $ret;
         }
     };
-    (fn $name:ident($($arg:ident: $typ:ty),*)) => {
-        define_syscall!(fn $name($($arg: $typ),*) -> ());
+    ($(#[$attr:meta])* fn $name:ident($($arg:ident: $typ:ty),*)) => {
+        define_syscall!($(#[$attr])* fn $name($($arg: $typ),*) -> ());
     }
 }
 

sysvar/src/clock.rs

@@ -130,8 +130,74 @@ pub use {
 };
 
 impl Sysvar for Clock {
-    impl_sysvar_get!(sol_get_clock_sysvar);
+    impl_sysvar_get!(id());
 }
 
 #[cfg(feature = "bincode")]
 impl SysvarSerialize for Clock {}
+
+#[cfg(test)]
+mod tests {
+    use {super::*, crate::tests::to_bytes, serial_test::serial};
+
+    #[test]
+    #[serial]
+    fn test_clock_get_uses_sysvar_syscall() {
+        let expected = Clock {
+            slot: 1,
+            epoch_start_timestamp: 2,
+            epoch: 3,
+            leader_schedule_epoch: 4,
+            unix_timestamp: 5,
+        };
+
+        let data = to_bytes(&expected);
+        crate::tests::mock_get_sysvar_syscall(&data);
+
+        let got = Clock::get().unwrap();
+        assert_eq!(got, expected);
+    }
+
+    struct ValidateIdSyscall {
+        data: Vec<u8>,
+    }
+
+    impl crate::program_stubs::SyscallStubs for ValidateIdSyscall {
+        fn sol_get_sysvar(
+            &self,
+            sysvar_id_addr: *const u8,
+            var_addr: *mut u8,
+            offset: u64,
+            length: u64,
+        ) -> u64 {
+            // Validate that the macro passed the correct sysvar id pointer
+            let passed_id = unsafe { *(sysvar_id_addr as *const solana_pubkey::Pubkey) };
+            assert_eq!(passed_id, id());
+
+            let slice = unsafe { std::slice::from_raw_parts_mut(var_addr, length as usize) };
+            slice.copy_from_slice(
+                &self.data[offset as usize..(offset.saturating_add(length)) as usize],
+            );
+            solana_program_entrypoint::SUCCESS
+        }
+    }
+
+    #[test]
+    #[serial]
+    fn test_clock_get_passes_correct_sysvar_id() {
+        let expected = Clock {
+            slot: 11,
+            epoch_start_timestamp: 22,
+            epoch: 33,
+            leader_schedule_epoch: 44,
+            unix_timestamp: 55,
+        };
+        let data = to_bytes(&expected);
+        let prev = crate::program_stubs::set_syscall_stubs(Box::new(ValidateIdSyscall { data }));
+
+        let got = Clock::get().unwrap();
+        assert_eq!(got, expected);
+
+        let _ = crate::program_stubs::set_syscall_stubs(prev);
+    }
+}

sysvar/src/epoch_rewards.rs

@@ -163,8 +163,33 @@ pub use {
 };
 
 impl Sysvar for EpochRewards {
-    impl_sysvar_get!(sol_get_epoch_rewards_sysvar);
+    impl_sysvar_get!(id());
 }
 
 #[cfg(feature = "bincode")]
 impl SysvarSerialize for EpochRewards {}
+
+#[cfg(test)]
+mod tests {
+    use {super::*, crate::tests::to_bytes, serial_test::serial};
+
+    #[test]
+    #[serial]
+    fn test_epoch_rewards_get_uses_sysvar_syscall() {
+        let expected = EpochRewards {
+            distribution_starting_block_height: 42,
+            num_partitions: 7,
+            parent_blockhash: solana_hash::Hash::new_unique(),
+            total_points: 1234567890,
+            total_rewards: 100,
+            distributed_rewards: 10,
+            active: true,
+        };
+
+        let data = to_bytes(&expected);
+        crate::tests::mock_get_sysvar_syscall(&data);
+
+        let got = EpochRewards::get().unwrap();
+        assert_eq!(got, expected);
+    }
+}

sysvar/src/epoch_schedule.rs

@@ -128,8 +128,24 @@ pub use {
 };
 
 impl Sysvar for EpochSchedule {
-    impl_sysvar_get!(sol_get_epoch_schedule_sysvar);
+    impl_sysvar_get!(id());
 }
 
 #[cfg(feature = "bincode")]
 impl SysvarSerialize for EpochSchedule {}
+
+#[cfg(test)]
+mod tests {
+    use {super::*, crate::tests::to_bytes, serial_test::serial};
+
+    #[test]
+    #[serial]
+    fn test_epoch_schedule_get_uses_sysvar_syscall() {
+        let expected = EpochSchedule::custom(1234, 5678, false);
+        let data = to_bytes(&expected);
+        crate::tests::mock_get_sysvar_syscall(&data);
+
+        let got = EpochSchedule::get().unwrap();
+        assert_eq!(got, expected);
+    }
+}

sysvar/src/fees.rs

@@ -64,7 +64,7 @@ impl SysvarSerialize for Fees {}
 
 #[cfg(test)]
 mod tests {
-    use super::*;
+    use {super::*, serial_test::serial};
 
     #[test]
     fn test_clone() {
@@ -76,4 +76,50 @@ mod tests {
         let cloned_fees = fees.clone();
         assert_eq!(cloned_fees, fees);
     }
+
+    struct MockFeesSyscall;
+    impl crate::program_stubs::SyscallStubs for MockFeesSyscall {
+        fn sol_get_fees_sysvar(&self, var_addr: *mut u8) -> u64 {
+            let fees = Fees {
+                fee_calculator: FeeCalculator {
+                    lamports_per_signature: 42,
+                },
+            };
+            unsafe {
+                std::ptr::copy_nonoverlapping(
+                    &fees as *const _ as *const u8,
+                    var_addr,
+                    core::mem::size_of::<Fees>(),
+                );
+            }
+            solana_program_entrypoint::SUCCESS
+        }
+    }
+
+    #[test]
+    #[serial]
+    fn test_fees_get_deprecated_syscall_path() {
+        let _ = crate::program_stubs::set_syscall_stubs(Box::new(MockFeesSyscall));
+        let got = Fees::get().unwrap();
+        assert_eq!(got.fee_calculator.lamports_per_signature, 42);
+    }
+
+    struct FailFeesSyscall;
+    impl crate::program_stubs::SyscallStubs for FailFeesSyscall {
+        fn sol_get_fees_sysvar(&self, _var_addr: *mut u8) -> u64 {
+            9999
+        }
+    }
+
+    #[test]
+    #[serial]
+    fn test_fees_get_deprecated_non_success_maps_to_unsupported() {
+        let prev = crate::program_stubs::set_syscall_stubs(Box::new(FailFeesSyscall));
+        let got = Fees::get();
+        assert_eq!(
+            got,
+            Err(solana_program_error::ProgramError::UnsupportedSysvar)
+        );
+        let _ = crate::program_stubs::set_syscall_stubs(prev);
+    }
 }

sysvar/src/last_restart_slot.rs

@@ -45,8 +45,26 @@ pub use {
 };
 
 impl Sysvar for LastRestartSlot {
-    impl_sysvar_get!(sol_get_last_restart_slot);
+    impl_sysvar_get!(id());
 }
 
 #[cfg(feature = "bincode")]
 impl SysvarSerialize for LastRestartSlot {}
+
+#[cfg(test)]
+mod tests {
+    use {super::*, crate::tests::to_bytes, serial_test::serial};
+
+    #[test]
+    #[serial]
+    fn test_last_restart_slot_get_uses_sysvar_syscall() {
+        let expected = LastRestartSlot {
+            last_restart_slot: 9999,
+        };
+        let data = to_bytes(&expected);
+        crate::tests::mock_get_sysvar_syscall(&data);
+
+        let got = LastRestartSlot::get().unwrap();
+        assert_eq!(got, expected);
+    }
+}

sysvar/src/lib.rs

@@ -161,6 +161,9 @@ pub trait SysvarSerialize:
 /// Implements the [`Sysvar::get`] method for both SBF and host targets.
 #[macro_export]
 macro_rules! impl_sysvar_get {
+    // DEPRECATED: This variant is only for the deprecated Fees sysvar and should be
+    // removed once Fees is no longer in use. It uses the old-style direct syscall
+    // approach instead of the new sol_get_sysvar syscall.
     ($syscall_name:ident) => {
         fn get() -> Result<Self, $crate::__private::ProgramError> {
             let mut var = Self::default();
@@ -179,6 +182,24 @@ macro_rules! impl_sysvar_get {
             }
         }
     };
+    ($sysvar_id:expr) => {
+        fn get() -> Result<Self, $crate::__private::ProgramError> {
+            // Allocate uninitialized memory for the sysvar struct
+            let mut uninit = core::mem::MaybeUninit::<Self>::uninit();
+            let size = core::mem::size_of::<Self>() as u64;
+            // Safety: we build a mutable slice pointing to the uninitialized
+            // buffer.  The `get_sysvar` syscall will fill exactly `size`
+            // bytes, after which the buffer is fully initialised.
+            let dst = unsafe {
+                core::slice::from_raw_parts_mut(uninit.as_mut_ptr() as *mut u8, size as usize)
+            };
+            // Attempt to load the sysvar data using the provided sysvar id.
+            $crate::get_sysvar(dst, &$sysvar_id, 0, size)?;
+            // Safety: `get_sysvar` succeeded and initialised the buffer.
+            let var = unsafe { uninit.assume_init() };
+            Ok(var)
+        }
+    };
 }
 
 /// Handler for retrieving a slice of sysvar data from the `sol_get_sysvar`
@@ -269,6 +290,19 @@ mod tests {
         }));
     }
 
+    /// Convert a value to its in-memory byte representation.
+    ///
+    /// Safety: This relies on the type's plain old data layout. Intended for tests.
+    pub fn to_bytes<T>(value: &T) -> Vec<u8> {
+        unsafe {
+            let size = core::mem::size_of::<T>();
+            let ptr = (value as *const T) as *const u8;
+            let mut data = vec![0u8; size];
+            std::ptr::copy_nonoverlapping(ptr, data.as_mut_ptr(), size);
+            data
+        }
+    }
+
     #[test]
     fn test_sysvar_account_info_to_from() {
         let test_sysvar = TestSysvar::default();

sysvar/src/program_stubs.rs

@@ -155,32 +155,6 @@ pub(crate) fn sol_get_sysvar(
         .sol_get_sysvar(sysvar_id_addr, var_addr, offset, length)
 }
 
-pub(crate) fn sol_get_clock_sysvar(var_addr: *mut u8) -> u64 {
-    SYSCALL_STUBS.read().unwrap().sol_get_clock_sysvar(var_addr)
-}
-
-pub(crate) fn sol_get_epoch_schedule_sysvar(var_addr: *mut u8) -> u64 {
-    SYSCALL_STUBS
-        .read()
-        .unwrap()
-        .sol_get_epoch_schedule_sysvar(var_addr)
-}
-
-pub(crate) fn sol_get_fees_sysvar(var_addr: *mut u8) -> u64 {
-    SYSCALL_STUBS.read().unwrap().sol_get_fees_sysvar(var_addr)
-}
-
-pub(crate) fn sol_get_rent_sysvar(var_addr: *mut u8) -> u64 {
-    SYSCALL_STUBS.read().unwrap().sol_get_rent_sysvar(var_addr)
-}
-
-pub(crate) fn sol_get_last_restart_slot(var_addr: *mut u8) -> u64 {
-    SYSCALL_STUBS
-        .read()
-        .unwrap()
-        .sol_get_last_restart_slot(var_addr)
-}
-
 pub fn sol_get_epoch_stake(vote_address: *const u8) -> u64 {
     SYSCALL_STUBS
         .read()
@@ -211,9 +185,6 @@ pub fn sol_get_stack_height() -> u64 {
     SYSCALL_STUBS.read().unwrap().sol_get_stack_height()
 }
 
-pub(crate) fn sol_get_epoch_rewards_sysvar(var_addr: *mut u8) -> u64 {
-    SYSCALL_STUBS
-        .read()
-        .unwrap()
-        .sol_get_epoch_rewards_sysvar(var_addr)
+pub(crate) fn sol_get_fees_sysvar(var_addr: *mut u8) -> u64 {
+    SYSCALL_STUBS.read().unwrap().sol_get_fees_sysvar(var_addr)
 }