continue file data PDU

.idea/runConfigurations/Check.xml

@@ -0,0 +1,19 @@
+<component name="ProjectRunConfigurationManager">
+  <configuration default="false" name="Check" type="CargoCommandRunConfiguration" factoryName="Cargo Command">
+    <option name="command" value="check --all-features" />
+    <option name="workingDirectory" value="file://$PROJECT_DIR$" />
+    <option name="emulateTerminal" value="false" />
+    <option name="channel" value="DEFAULT" />
+    <option name="requiredFeatures" value="true" />
+    <option name="allFeatures" value="true" />
+    <option name="withSudo" value="false" />
+    <option name="buildTarget" value="REMOTE" />
+    <option name="backtrace" value="SHORT" />
+    <envs />
+    <option name="isRedirectInput" value="false" />
+    <option name="redirectInputPath" value="" />
+    <method v="2">
+      <option name="CARGO.BUILD_TASK_PROVIDER" enabled="true" />
+    </method>
+  </configuration>
+</component>

src/cfdp/pdu/file_data.rs

@@ -1,4 +1,4 @@
-use crate::cfdp::pdu::{write_file_size, PduError, PduHeader};
+use crate::cfdp::pdu::{read_fss_field, write_fss_field, PduError, PduHeader};
 use crate::cfdp::{CrcFlag, LargeFileFlag, PduType, SegmentMetadataFlag};
 use crate::{ByteConversionError, SizeMissmatch};
 use num_enum::{IntoPrimitive, TryFromPrimitive};
@@ -23,12 +23,12 @@ pub struct SegmentMetadata<'seg_meta> {
     metadata: Option<&'seg_meta [u8]>,
 }
 
-impl SegmentMetadata<'_> {
+impl<'seg_meta> SegmentMetadata<'seg_meta> {
     pub fn written_len(&self) -> usize {
         1 + self.seg_metadata_len as usize
     }
 
-    pub fn write_to_bytes(&self, buf: &mut [u8]) -> Result<usize, ByteConversionError> {
+    pub(crate) fn write_to_bytes(&self, buf: &mut [u8]) -> Result<usize, ByteConversionError> {
         if buf.len() < self.written_len() {
             return Err(ByteConversionError::ToSliceTooSmall(SizeMissmatch {
                 found: buf.len(),
@@ -41,6 +41,27 @@ impl SegmentMetadata<'_> {
         }
         Ok(self.written_len())
     }
+
+    pub(crate) fn from_bytes(buf: &'seg_meta [u8]) -> Result<Self, ByteConversionError> {
+        if buf.is_empty() {
+            return Err(ByteConversionError::FromSliceTooSmall(SizeMissmatch {
+                found: buf.len(),
+                expected: 2,
+            }));
+        }
+        let mut metadata = None;
+        let seg_metadata_len = (buf[0] & 0b111111) as usize;
+        if seg_metadata_len > 0 {
+            metadata = Some(&buf[1..1 + seg_metadata_len]);
+        }
+        Ok(Self {
+            // Can't fail, only 2 bits
+            record_continuation_state: RecordContinuationState::try_from((buf[0] >> 6) & 0b11)
+                .unwrap(),
+            seg_metadata_len: seg_metadata_len as u8,
+            metadata,
+        })
+    }
 }
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]
@@ -81,30 +102,33 @@ impl<'seg_meta, 'file_data> FileDataPdu<'seg_meta, 'file_data> {
         if segment_metadata.is_some() {
             pdu_header.seg_metadata_flag = SegmentMetadataFlag::Present;
         }
-        Self {
+        let mut pdu = Self {
             pdu_header,
             segment_metadata,
             offset,
             file_data,
-        }
+        };
+        pdu.pdu_header.pdu_datafield_len = pdu.calc_pdu_datafield_len() as u16;
+        pdu
     }
 
-    pub fn written_len(&self) -> usize {
+    fn calc_pdu_datafield_len(&self) -> usize {
-        let mut len = self.pdu_header.header_len();
+        let mut len = core::mem::size_of::<u32>();
-        if self.segment_metadata.is_some() {
-            len += self.segment_metadata.as_ref().unwrap().written_len()
-        }
-        // Regular file size
-        len += core::mem::size_of::<u32>();
         if self.pdu_header.pdu_conf.file_flag == LargeFileFlag::Large {
             len += core::mem::size_of::<u32>();
         }
+        if self.segment_metadata.is_some() {
+            len += self.segment_metadata.as_ref().unwrap().written_len()
+        }
         len += self.file_data.len();
         if self.pdu_header.pdu_conf.crc_flag == CrcFlag::WithCrc {
             len += 2;
         }
         len
     }
+    pub fn written_len(&self) -> usize {
+        self.pdu_header.header_len() + self.calc_pdu_datafield_len()
+    }
 
     pub fn offset(&self) -> u64 {
         self.offset
@@ -114,7 +138,7 @@ impl<'seg_meta, 'file_data> FileDataPdu<'seg_meta, 'file_data> {
         self.file_data
     }
 
-    pub fn seg_metadata(&self) -> Option<&SegmentMetadata> {
+    pub fn segment_metadata(&self) -> Option<&SegmentMetadata> {
         self.segment_metadata.as_ref()
     }
 
@@ -134,15 +158,51 @@ impl<'seg_meta, 'file_data> FileDataPdu<'seg_meta, 'file_data> {
                 .unwrap()
                 .write_to_bytes(&mut buf[current_idx..])?;
         }
-        write_file_size(
+        current_idx += write_fss_field(
-            &mut current_idx,
             self.pdu_header.common_pdu_conf().file_flag,
             self.offset,
-            buf,
+            &mut buf[current_idx..],
         )?;
         buf[current_idx..current_idx + self.file_data.len()].copy_from_slice(self.file_data);
+        current_idx += self.file_data.len();
         Ok(current_idx)
     }
+
+    pub fn from_bytes<'longest: 'seg_meta + 'file_data>(
+        buf: &'longest [u8],
+    ) -> Result<Self, PduError> {
+        let (pdu_header, mut current_idx) = PduHeader::from_bytes(buf)?;
+        let full_len_without_crc = pdu_header.verify_length_and_checksum(buf)?;
+        let mut min_expected_len = current_idx + core::mem::size_of::<u32>();
+        min_expected_len = core::cmp::max(min_expected_len, pdu_header.pdu_len());
+        if buf.len() < min_expected_len {
+            return Err(ByteConversionError::FromSliceTooSmall(SizeMissmatch {
+                found: buf.len(),
+                expected: min_expected_len,
+            })
+            .into());
+        }
+        let mut segment_metadata = None;
+        if pdu_header.seg_metadata_flag == SegmentMetadataFlag::Present {
+            segment_metadata = Some(SegmentMetadata::from_bytes(&buf[current_idx..])?);
+            current_idx += segment_metadata.as_ref().unwrap().written_len();
+        }
+        let (fss, offset) = read_fss_field(pdu_header.pdu_conf.file_flag, &buf[current_idx..]);
+        current_idx += fss;
+        if current_idx > full_len_without_crc {
+            return Err(ByteConversionError::FromSliceTooSmall(SizeMissmatch {
+                found: current_idx,
+                expected: full_len_without_crc,
+            })
+            .into());
+        }
+        Ok(Self {
+            pdu_header,
+            segment_metadata,
+            offset,
+            file_data: &buf[current_idx..full_len_without_crc],
+        })
+    }
 }
 
 #[cfg(test)]
@@ -163,5 +223,63 @@ mod tests {
         let fd_pdu = FileDataPdu::new_no_seg_metadata(pdu_header, 10, &file_data);
         assert_eq!(fd_pdu.file_data(), file_data);
         assert_eq!(fd_pdu.offset(), 10);
+        assert!(fd_pdu.segment_metadata().is_none());
+        assert_eq!(
+            fd_pdu.written_len(),
+            fd_pdu.pdu_header.header_len() + core::mem::size_of::<u32>() + 4
+        );
+    }
+
+    #[test]
+    fn test_serialization() {
+        let src_id = UbfU8::new(1);
+        let dest_id = UbfU8::new(2);
+        let transaction_seq_num = UbfU8::new(3);
+        let common_conf =
+            CommonPduConfig::new_with_defaults(src_id, dest_id, transaction_seq_num).unwrap();
+        let pdu_header = PduHeader::new_for_file_data_default(common_conf, 0);
+        let file_data: [u8; 4] = [1, 2, 3, 4];
+        let fd_pdu = FileDataPdu::new_no_seg_metadata(pdu_header, 10, &file_data);
+        let mut buf: [u8; 32] = [0; 32];
+        let res = fd_pdu.write_to_bytes(&mut buf);
+        assert!(res.is_ok());
+        let written = res.unwrap();
+        assert_eq!(
+            written,
+            fd_pdu.pdu_header.header_len() + core::mem::size_of::<u32>() + 4
+        );
+        let mut current_idx = fd_pdu.pdu_header.header_len();
+        let file_size = u32::from_be_bytes(
+            buf[fd_pdu.pdu_header.header_len()..fd_pdu.pdu_header.header_len() + 4]
+                .try_into()
+                .unwrap(),
+        );
+        current_idx += 4;
+        assert_eq!(file_size, 10);
+        assert_eq!(buf[current_idx], 1);
+        current_idx += 1;
+        assert_eq!(buf[current_idx], 2);
+        current_idx += 1;
+        assert_eq!(buf[current_idx], 3);
+        current_idx += 1;
+        assert_eq!(buf[current_idx], 4);
+    }
+
+    #[test]
+    fn test_deserialization() {
+        let src_id = UbfU8::new(1);
+        let dest_id = UbfU8::new(2);
+        let transaction_seq_num = UbfU8::new(3);
+        let common_conf =
+            CommonPduConfig::new_with_defaults(src_id, dest_id, transaction_seq_num).unwrap();
+        let pdu_header = PduHeader::new_for_file_data_default(common_conf, 0);
+        let file_data: [u8; 4] = [1, 2, 3, 4];
+        let fd_pdu = FileDataPdu::new_no_seg_metadata(pdu_header, 10, &file_data);
+        let mut buf: [u8; 32] = [0; 32];
+        fd_pdu.write_to_bytes(&mut buf).unwrap();
+        let fd_pdu_read_back = FileDataPdu::from_bytes(&buf);
+        assert!(fd_pdu_read_back.is_ok());
+        let fd_pdu_read_back = fd_pdu_read_back.unwrap();
+        assert_eq!(fd_pdu_read_back, fd_pdu);
     }
 }

src/cfdp/pdu/metadata.rs

@@ -1,5 +1,5 @@
 use crate::cfdp::lv::Lv;
-use crate::cfdp::pdu::{write_file_size, FileDirectiveType, PduError, PduHeader};
+use crate::cfdp::pdu::{read_fss_field, write_fss_field, FileDirectiveType, PduError, PduHeader};
 use crate::cfdp::tlv::Tlv;
 use crate::cfdp::{ChecksumType, CrcFlag, LargeFileFlag, PduType};
 use crate::{ByteConversionError, SizeMissmatch, CRC_CCITT_FALSE};
@@ -131,26 +131,15 @@ impl<'src_name, 'dest_name, 'opts> MetadataPdu<'src_name, 'dest_name, 'opts> {
         options: Option<&'opts [u8]>,
     ) -> Self {
         pdu_header.pdu_type = PduType::FileDirective;
-        let is_large_file = pdu_header.common_pdu_conf().file_flag == LargeFileFlag::Large;
+        let mut pdu = Self {
-        let has_crc = pdu_header.common_pdu_conf().crc_flag == CrcFlag::WithCrc;
-        pdu_header.pdu_datafield_len =
-            2 + 4 + src_file_name.len_full() as u16 + dest_file_name.len_full() as u16;
-        if is_large_file {
-            pdu_header.pdu_datafield_len += 4;
-        }
-        if has_crc {
-            pdu_header.pdu_datafield_len += 2;
-        }
-        if let Some(opts) = options {
-            pdu_header.pdu_datafield_len += opts.len() as u16;
-        }
-        Self {
             pdu_header,
             metadata_params,
             src_file_name,
             dest_file_name,
             options,
-        }
+        };
+        pdu.pdu_header.pdu_datafield_len = pdu.calc_pdu_datafield_len() as u16;
+        pdu
     }
 
     pub fn src_file_name(&self) -> Lv<'src_name> {
@@ -177,7 +166,12 @@ impl<'src_name, 'dest_name, 'opts> MetadataPdu<'src_name, 'dest_name, 'opts> {
 
     pub fn written_len(&self) -> usize {
         // One directive type octet, and one byte of the parameter field.
-        let mut len = self.pdu_header.header_len() + 2;
+        self.pdu_header.header_len() + self.calc_pdu_datafield_len()
+    }
+
+    fn calc_pdu_datafield_len(&self) -> usize {
+        // One directve type octet and one byte of the directive parameter field.
+        let mut len = 2;
         if self.pdu_header.common_pdu_conf().file_flag == LargeFileFlag::Large {
             len += 8;
         } else {
@@ -214,11 +208,10 @@ impl<'src_name, 'dest_name, 'opts> MetadataPdu<'src_name, 'dest_name, 'opts> {
         buf[current_idx] = ((self.metadata_params.closure_requested as u8) << 7)
             | (self.metadata_params.checksum_type as u8);
         current_idx += 1;
-        write_file_size(
+        current_idx += write_fss_field(
-            &mut current_idx,
             self.pdu_header.common_pdu_conf().file_flag,
             self.metadata_params.file_size,
-            buf,
+            &mut buf[current_idx..],
         )?;
         current_idx += self
             .src_file_name
@@ -241,7 +234,7 @@ impl<'src_name, 'dest_name, 'opts> MetadataPdu<'src_name, 'dest_name, 'opts> {
 
     pub fn from_bytes<'longest: 'src_name + 'dest_name + 'opts>(
         buf: &'longest [u8],
-    ) -> Result<MetadataPdu<'src_name, 'dest_name, 'opts>, PduError> {
+    ) -> Result<Self, PduError> {
         let (pdu_header, mut current_idx) = PduHeader::from_bytes(buf)?;
         let full_len_without_crc = pdu_header.verify_length_and_checksum(buf)?;
         let is_large_file = pdu_header.pdu_conf.file_flag == LargeFileFlag::Large;
@@ -268,22 +261,15 @@ impl<'src_name, 'dest_name, 'opts> MetadataPdu<'src_name, 'dest_name, 'opts> {
             )));
         }
         current_idx += 1;
-
+        let (fss_len, file_size) =
-        let file_size = if pdu_header.pdu_conf.file_flag == LargeFileFlag::Large {
+            read_fss_field(pdu_header.pdu_conf.file_flag, &buf[current_idx + 1..]);
-            u64::from_be_bytes(buf[current_idx + 1..current_idx + 9].try_into().unwrap())
-        } else {
-            u32::from_be_bytes(buf[current_idx + 1..current_idx + 5].try_into().unwrap()) as u64
-        };
         let metadata_params = MetadataGenericParams {
             closure_requested: ((buf[current_idx] >> 6) & 0b1) != 0,
             checksum_type: ChecksumType::try_from(buf[current_idx] & 0b1111)
                 .map_err(|_| PduError::InvalidChecksumType(buf[current_idx] & 0b1111))?,
             file_size,
         };
-        current_idx += 5;
+        current_idx += 1 + fss_len;
-        if is_large_file {
-            current_idx += 4;
-        }
         let src_file_name = Lv::from_bytes(&buf[current_idx..])?;
         current_idx += src_file_name.len_full();
         let dest_file_name = Lv::from_bytes(&buf[current_idx..])?;
@@ -343,7 +329,7 @@ pub mod tests {
         MetadataPdu<'static, 'static, 'opts>,
     ) {
         let pdu_header = PduHeader::new_no_file_data(common_pdu_conf(crc_flag, fss), 0);
-        let metadata_params = MetadataGenericParams::new(false, ChecksumType::Crc32, 10);
+        let metadata_params = MetadataGenericParams::new(false, ChecksumType::Crc32, 0x1010);
         let src_filename = Lv::new_from_str(SRC_FILENAME).expect("Generating string LV failed");
         let dest_filename =
             Lv::new_from_str(DEST_FILENAME).expect("Generating destination LV failed");
@@ -399,7 +385,7 @@ pub mod tests {
         assert_eq!(buf[7], FileDirectiveType::MetadataPdu as u8);
         assert_eq!(buf[8] >> 6, false as u8);
         assert_eq!(buf[8] & 0b1111, ChecksumType::Crc32 as u8);
-        assert_eq!(u32::from_be_bytes(buf[9..13].try_into().unwrap()), 10);
+        assert_eq!(u32::from_be_bytes(buf[9..13].try_into().unwrap()), 0x1010);
         let mut current_idx = 13;
         let src_name_from_raw =
             Lv::from_bytes(&buf[current_idx..]).expect("Creating source name LV failed");

src/cfdp/pdu/mod.rs

@@ -468,25 +468,35 @@ impl PduHeader {
     }
 }
 
-pub(crate) fn write_file_size(
+pub(crate) fn write_fss_field(
-    current_idx: &mut usize,
+    file_flag: LargeFileFlag,
-    fss: LargeFileFlag,
     file_size: u64,
     buf: &mut [u8],
-) -> Result<(), PduError> {
+) -> Result<usize, PduError> {
-    if fss == LargeFileFlag::Large {
+    Ok(if file_flag == LargeFileFlag::Large {
-        buf[*current_idx..*current_idx + core::mem::size_of::<u64>()]
+        buf[..core::mem::size_of::<u64>()].copy_from_slice(&file_size.to_be_bytes());
-            .copy_from_slice(&file_size.to_be_bytes());
+        core::mem::size_of::<u64>()
-        *current_idx += core::mem::size_of::<u64>()
     } else {
         if file_size > u32::MAX as u64 {
             return Err(PduError::FileSizeTooLarge(file_size));
         }
-        buf[*current_idx..*current_idx + core::mem::size_of::<u32>()]
+        buf[..core::mem::size_of::<u32>()].copy_from_slice(&(file_size as u32).to_be_bytes());
-            .copy_from_slice(&(file_size as u32).to_be_bytes());
+        core::mem::size_of::<u32>()
-        *current_idx += core::mem::size_of::<u32>()
+    })
+}
+
+pub(crate) fn read_fss_field(file_flag: LargeFileFlag, buf: &[u8]) -> (usize, u64) {
+    if file_flag == LargeFileFlag::Large {
+        (
+            core::mem::size_of::<u64>(),
+            u64::from_be_bytes(buf[..core::mem::size_of::<u64>()].try_into().unwrap()),
+        )
+    } else {
+        (
+            core::mem::size_of::<u32>(),
+            u32::from_be_bytes(buf[..core::mem::size_of::<u32>()].try_into().unwrap()).into(),
+        )
     }
-    Ok(())
 }
 
 #[cfg(test)]