CHANGELOG.md

@@ -11,6 +11,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 ## Added
 
 - Add `WritablePduPacket` trait which is a common trait of all CFDP PDU implementations.
+- Add `CfdpPdu` trait which exposes fields and attributes common to all CFDP PDUs.
 
 ## Fixed
 
@@ -21,6 +22,9 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 - Renamed `SerializablePusPacket` to `WritablePusPacket`.
 - Renamed `WritablePduPacket.written_len` and `SerializablePusPacket.len_packed` to `len_written`.
+- Introduce custom implementation of `PartialEq` for `CommonPduConfig` which only compares the
+  values for the source entity ID, destination entity ID and transaction sequence number field to
+  allow those fields to have different widths.
 
 # [v0.7.0-beta.2] 2023-09-26
 

src/cfdp/pdu/eof.rs

@@ -8,7 +8,7 @@ use crate::ByteConversionError;
 #[cfg(feature = "serde")]
 use serde::{Deserialize, Serialize};
 
-use super::WritablePduPacket;
+use super::{CfdpPdu, WritablePduPacket};
 
 /// Finished PDU abstraction.
 ///
@@ -111,6 +111,16 @@ impl EofPdu {
     }
 }
 
+impl CfdpPdu for EofPdu {
+    fn pdu_header(&self) -> &PduHeader {
+        &self.pdu_header
+    }
+
+    fn file_directive_type(&self) -> Option<FileDirectiveType> {
+        Some(FileDirectiveType::EofPdu)
+    }
+}
+
 impl WritablePduPacket for EofPdu {
     fn write_to_bytes(&self, buf: &mut [u8]) -> Result<usize, PduError> {
         let expected_len = self.len_written();

src/cfdp/pdu/file_data.rs

@@ -8,7 +8,7 @@ use num_enum::{IntoPrimitive, TryFromPrimitive};
 #[cfg(feature = "serde")]
 use serde::{Deserialize, Serialize};
 
-use super::WritablePduPacket;
+use super::{CfdpPdu, FileDirectiveType, WritablePduPacket};
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, TryFromPrimitive, IntoPrimitive)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
@@ -191,6 +191,15 @@ impl<'seg_meta, 'file_data> FileDataPdu<'seg_meta, 'file_data> {
         })
     }
 }
+impl CfdpPdu for FileDataPdu<'_, '_> {
+    fn pdu_header(&self) -> &PduHeader {
+        &self.pdu_header
+    }
+
+    fn file_directive_type(&self) -> Option<FileDirectiveType> {
+        None
+    }
+}
 
 impl WritablePduPacket for FileDataPdu<'_, '_> {
     fn write_to_bytes(&self, buf: &mut [u8]) -> Result<usize, PduError> {

src/cfdp/pdu/finished.rs

@@ -8,7 +8,7 @@ use num_enum::{IntoPrimitive, TryFromPrimitive};
 #[cfg(feature = "serde")]
 use serde::{Deserialize, Serialize};
 
-use super::WritablePduPacket;
+use super::{CfdpPdu, WritablePduPacket};
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, TryFromPrimitive, IntoPrimitive)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
@@ -98,9 +98,6 @@ impl<'fs_responses> FinishedPdu<'fs_responses> {
         finished_pdu.pdu_header.pdu_datafield_len = finished_pdu.calc_pdu_datafield_len() as u16;
         finished_pdu
     }
-    pub fn pdu_header(&self) -> &PduHeader {
-        &self.pdu_header
-    }
 
     pub fn condition_code(&self) -> ConditionCode {
         self.condition_code
@@ -214,6 +211,16 @@ impl<'fs_responses> FinishedPdu<'fs_responses> {
     }
 }
 
+impl CfdpPdu for FinishedPdu<'_> {
+    fn pdu_header(&self) -> &PduHeader {
+        &self.pdu_header
+    }
+
+    fn file_directive_type(&self) -> Option<FileDirectiveType> {
+        Some(FileDirectiveType::FinishedPdu)
+    }
+}
+
 impl WritablePduPacket for FinishedPdu<'_> {
     fn write_to_bytes(&self, buf: &mut [u8]) -> Result<usize, PduError> {
         let expected_len = self.len_written();

src/cfdp/pdu/metadata.rs

@@ -11,7 +11,7 @@ use alloc::vec::Vec;
 #[cfg(feature = "serde")]
 use serde::{Deserialize, Serialize};
 
-use super::WritablePduPacket;
+use super::{CfdpPdu, WritablePduPacket};
 
 #[derive(Default, Debug, Copy, Clone, PartialEq, Eq)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
@@ -193,10 +193,6 @@ impl<'src_name, 'dest_name, 'opts> MetadataPdu<'src_name, 'dest_name, 'opts> {
         len
     }
 
-    pub fn pdu_header(&self) -> &PduHeader {
-        &self.pdu_header
-    }
-
     pub fn from_bytes<'longest: 'src_name + 'dest_name + 'opts>(
         buf: &'longest [u8],
     ) -> Result<Self, PduError> {
@@ -250,6 +246,16 @@ impl<'src_name, 'dest_name, 'opts> MetadataPdu<'src_name, 'dest_name, 'opts> {
     }
 }
 
+impl CfdpPdu for MetadataPdu<'_, '_, '_> {
+    fn pdu_header(&self) -> &PduHeader {
+        &self.pdu_header
+    }
+
+    fn file_directive_type(&self) -> Option<FileDirectiveType> {
+        Some(FileDirectiveType::MetadataPdu)
+    }
+}
+
 impl WritablePduPacket for MetadataPdu<'_, '_, '_> {
     fn write_to_bytes(&self, buf: &mut [u8]) -> Result<usize, PduError> {
         let expected_len = self.len_written();
@@ -300,12 +306,15 @@ pub mod tests {
         build_metadata_opts_from_slice, build_metadata_opts_from_vec, MetadataGenericParams,
         MetadataPdu,
     };
-    use crate::cfdp::pdu::tests::{common_pdu_conf, verify_raw_header};
+    use crate::cfdp::pdu::tests::{
-    use crate::cfdp::pdu::WritablePduPacket;
+        common_pdu_conf, verify_raw_header, TEST_DEST_ID, TEST_SEQ_NUM, TEST_SRC_ID,
+    };
+    use crate::cfdp::pdu::{CfdpPdu, WritablePduPacket};
     use crate::cfdp::pdu::{FileDirectiveType, PduHeader};
     use crate::cfdp::tlv::{Tlv, TlvType};
     use crate::cfdp::{
-        ChecksumType, CrcFlag, LargeFileFlag, PduType, SegmentMetadataFlag, SegmentationControl,
+        ChecksumType, CrcFlag, Direction, LargeFileFlag, PduType, SegmentMetadataFlag,
+        SegmentationControl, TransmissionMode,
     };
     use std::vec;
 
@@ -351,6 +360,21 @@ pub mod tests {
         assert_eq!(metadata_pdu.src_file_name(), src_filename);
         assert_eq!(metadata_pdu.dest_file_name(), dest_filename);
         assert_eq!(metadata_pdu.options(), None);
+        assert_eq!(metadata_pdu.crc_flag(), CrcFlag::NoCrc);
+        assert_eq!(metadata_pdu.file_flag(), LargeFileFlag::Normal);
+        assert_eq!(metadata_pdu.pdu_type(), PduType::FileDirective);
+        assert_eq!(
+            metadata_pdu.file_directive_type(),
+            Some(FileDirectiveType::MetadataPdu)
+        );
+        assert_eq!(
+            metadata_pdu.transmission_mode(),
+            TransmissionMode::Acknowledged
+        );
+        assert_eq!(metadata_pdu.direction(), Direction::TowardsReceiver);
+        assert_eq!(metadata_pdu.source_id(), TEST_SRC_ID.into());
+        assert_eq!(metadata_pdu.dest_id(), TEST_DEST_ID.into());
+        assert_eq!(metadata_pdu.transaction_seq_num(), TEST_SEQ_NUM.into());
     }
 
     #[test]
@@ -414,6 +438,7 @@ pub mod tests {
     fn test_with_crc_flag() {
         let (src_filename, dest_filename, metadata_pdu) =
             generic_metadata_pdu(CrcFlag::WithCrc, LargeFileFlag::Normal, None);
+        assert_eq!(metadata_pdu.crc_flag(), CrcFlag::WithCrc);
         let mut buf: [u8; 64] = [0; 64];
         let write_res = metadata_pdu.write_to_bytes(&mut buf);
         assert!(write_res.is_ok());

src/cfdp/pdu/mod.rs

@@ -165,8 +165,51 @@ pub trait WritablePduPacket {
     }
 }
 
+/// Abstraction trait for fields and properties common for all PDUs.
+pub trait CfdpPdu {
+    fn pdu_header(&self) -> &PduHeader;
+
+    fn source_id(&self) -> UnsignedByteField {
+        self.pdu_header().common_pdu_conf().source_entity_id
+    }
+
+    fn dest_id(&self) -> UnsignedByteField {
+        self.pdu_header().common_pdu_conf().dest_entity_id
+    }
+
+    fn transaction_seq_num(&self) -> UnsignedByteField {
+        self.pdu_header().common_pdu_conf().transaction_seq_num
+    }
+
+    fn transmission_mode(&self) -> TransmissionMode {
+        self.pdu_header().common_pdu_conf().trans_mode
+    }
+    fn direction(&self) -> Direction {
+        self.pdu_header().common_pdu_conf().direction
+    }
+
+    fn crc_flag(&self) -> CrcFlag {
+        self.pdu_header().common_pdu_conf().crc_flag
+    }
+
+    fn file_flag(&self) -> LargeFileFlag {
+        self.pdu_header().common_pdu_conf().file_flag
+    }
+
+    fn pdu_type(&self) -> PduType {
+        self.pdu_header().pdu_type()
+    }
+
+    fn file_directive_type(&self) -> Option<FileDirectiveType>;
+}
+
 /// Common configuration fields for a PDU.
-#[derive(Debug, Copy, Clone, PartialEq, Eq)]
+///
+/// Please note that this structure has a custom implementation of [PartialEq] which only
+/// compares the values for source entity ID, destination entity ID and transaction sequence
+/// number. This permits that those fields can have different widths, as long as the value is the
+/// same.
+#[derive(Debug, Copy, Clone, Eq)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub struct CommonPduConfig {
     source_entity_id: UnsignedByteField,
@@ -287,6 +330,18 @@ impl Default for CommonPduConfig {
     }
 }
 
+impl PartialEq for CommonPduConfig {
+    fn eq(&self, other: &Self) -> bool {
+        self.source_entity_id.value() == other.source_entity_id.value()
+            && self.dest_entity_id.value() == other.dest_entity_id.value()
+            && self.transaction_seq_num.value() == other.transaction_seq_num.value()
+            && self.trans_mode == other.trans_mode
+            && self.file_flag == other.file_flag
+            && self.crc_flag == other.crc_flag
+            && self.direction == other.direction
+    }
+}
+
 pub const FIXED_HEADER_LEN: usize = 4;
 
 /// Abstraction for the PDU header common to all CFDP PDUs.
@@ -627,17 +682,18 @@ mod tests {
         TransmissionMode, CFDP_VERSION_2,
     };
     use crate::util::{
-        UbfU8, UnsignedByteField, UnsignedByteFieldU16, UnsignedByteFieldU8, UnsignedEnum,
+        UbfU8, UnsignedByteField, UnsignedByteFieldU16, UnsignedByteFieldU8, UnsignedEnum, UbfU16,
     };
     use crate::ByteConversionError;
     use std::format;
 
+    pub(crate) const TEST_SRC_ID: UbfU8 = UbfU8::new(5);
+    pub(crate) const TEST_DEST_ID: UbfU8 = UbfU8::new(10);
+    pub(crate) const TEST_SEQ_NUM: UbfU8 = UbfU8::new(20);
+
     pub(crate) fn common_pdu_conf(crc_flag: CrcFlag, fss: LargeFileFlag) -> CommonPduConfig {
-        let src_id = UbfU8::new(5);
-        let dest_id = UbfU8::new(10);
-        let transaction_seq_num = UbfU8::new(20);
         let mut pdu_conf =
-            CommonPduConfig::new_with_byte_fields(src_id, dest_id, transaction_seq_num)
+            CommonPduConfig::new_with_byte_fields(TEST_SRC_ID, TEST_DEST_ID, TEST_SEQ_NUM)
                 .expect("Generating common PDU config");
         pdu_conf.crc_flag = crc_flag;
         pdu_conf.file_flag = fss;
@@ -728,6 +784,15 @@ mod tests {
         assert_eq!(pdu_header.header_len(), 7);
     }
 
+    #[test]
+    fn test_common_pdu_conf_partial_eq() {
+        let common_pdu_cfg_0 = CommonPduConfig::new_with_byte_fields(UbfU8::new(1), UbfU8::new(2), UbfU8::new(3))
+            .expect("common config creation failed");
+        let common_pdu_cfg_1 = CommonPduConfig::new_with_byte_fields(UbfU16::new(1), UbfU16::new(2), UbfU16::new(3))
+            .expect("common config creation failed");
+        assert_eq!(common_pdu_cfg_0, common_pdu_cfg_1);
+    }
+
     #[test]
     fn test_basic_state_default() {
         let default_conf = CommonPduConfig::default();