Merge Read/Seek stream input traits

src/elf_stream.rs

@@ -13,7 +13,7 @@ use crate::file::{parse_ident, Class};
 use crate::gnu_symver::{
     SymbolVersionTable, VerDefIterator, VerNeedIterator, VersionIndex, VersionIndexTable,
 };
-use crate::io_traits::{Read, Seek, SeekFrom};
+use crate::io_traits::{InputStream, SeekFrom};
 use crate::note::NoteIterator;
 use crate::parse::{ParseAt, ParseError};
 use crate::relocation::{RelIterator, RelaIterator};
@@ -28,7 +28,7 @@ use crate::file::FileHeader;
 /// This type encapsulates the stream-oriented interface for parsing ELF objects from
 /// a `Read + Seek`.
 #[derive(Debug)]
-pub struct ElfStream<E: EndianParse, S: Read + Seek> {
+pub struct ElfStream<E: EndianParse, S: InputStream> {
     pub ehdr: FileHeader<E>,
     shdrs: Vec<SectionHeader>,
     phdrs: Vec<ProgramHeader>,
@@ -40,7 +40,7 @@ pub struct ElfStream<E: EndianParse, S: Read + Seek> {
 /// Returns a [ParseError] if the data bytes for the section table cannot be read.
 /// i.e. if the ELF [FileHeader]'s e_shnum, e_shoff, e_shentsize are invalid and point
 /// to a range in the file data that does not actually exist, or if any of the headers failed to parse.
-fn parse_section_headers<E: EndianParse, S: Read + Seek>(
+fn parse_section_headers<E: EndianParse, S: InputStream>(
     ehdr: &FileHeader<E>,
     reader: &mut CachingReader<S>,
 ) -> Result<Vec<SectionHeader>, ParseError> {
@@ -78,7 +78,7 @@ fn parse_section_headers<E: EndianParse, S: Read + Seek>(
     Ok(shdr_vec)
 }
 
-fn parse_program_headers<E: EndianParse, S: Read + Seek>(
+fn parse_program_headers<E: EndianParse, S: InputStream>(
     ehdr: &FileHeader<E>,
     reader: &mut CachingReader<S>,
 ) -> Result<Vec<ProgramHeader>, ParseError> {
@@ -117,7 +117,7 @@ fn parse_program_headers<E: EndianParse, S: Read + Seek>(
     Ok(phdrs_vec)
 }
 
-impl<E: EndianParse, S: Read + Seek> ElfStream<E, S> {
+impl<E: EndianParse, S: InputStream> ElfStream<E, S> {
     /// Do a minimal amount of parsing work to open an [ElfStream] handle from a Read+Seek containing an ELF object.
     ///
     /// This parses the ELF [FileHeader], [SectionHeader] table, and [ProgramHeader] (segments) table.
@@ -680,13 +680,13 @@ impl<E: EndianParse, S: Read + Seek> ElfStream<E, S> {
 }
 
 #[derive(Debug)]
-struct CachingReader<R: Read + Seek> {
+struct CachingReader<R: InputStream> {
     reader: R,
     stream_len: u64,
     bufs: BufferMap<(usize, usize), Box<[u8]>>,
 }
 
-impl<R: Read + Seek> CachingReader<R> {
+impl<R: InputStream> CachingReader<R> {
     fn new(mut reader: R) -> Result<Self, ParseError> {
         // Cache the size of the stream so that we can err (rather than OOM) on invalid
         // huge read requests.

src/io_traits.rs

@@ -14,31 +14,19 @@ pub enum SeekFrom {
     Current(i64),
 }
 
-pub trait Read {
+pub trait InputStream {
-    fn read(&mut self, buf: &mut [u8]) -> Result<usize, StreamError>;
-
     fn read_exact(&mut self, buf: &mut [u8]) -> Result<(), StreamError>;
-}
 
-pub trait Seek {
     fn seek(&mut self, pos: SeekFrom) -> Result<u64, StreamError>;
 }
 
 #[cfg(feature = "std")]
-impl<R: std::io::Read> Read for R {
+impl<R: std::io::Read> InputStream for R {
-    #[inline]
-    fn read(&mut self, buf: &mut [u8]) -> Result<usize, StreamError> {
-        std::io::Read::read(self, buf)
-    }
-
     #[inline]
     fn read_exact(&mut self, buf: &mut [u8]) -> Result<(), StreamError> {
         std::io::Read::read_exact(self, buf)
     }
-}
 
-#[cfg(feature = "std")]
-impl<S: std::io::Seek> Seek for S {
     #[inline]
     fn seek(&mut self, pos: SeekFrom) -> Result<u64, StreamError> {
         std::io::Seek::seek(self, pos.into())
@@ -58,7 +46,7 @@ impl From<SeekFrom> for std::io::SeekFrom {
 
 #[cfg(not(feature = "std"))]
 impl From<StreamError> for crate::ParseError {
-    fn from(e: StreamError) -> Self {
+    fn from(_e: StreamError) -> Self {
         todo!()
     }
 }
@@ -67,7 +55,7 @@ impl From<StreamError> for crate::ParseError {
 mod no_std_stream_tests {
     use crate::{abi, endian::AnyEndian, ElfStream};
 
-    use super::{Read, Seek, SeekFrom, StreamError};
+    use super::{InputStream, SeekFrom, StreamError};
 
     pub struct NoStdStream {
         pos: usize,
@@ -81,11 +69,7 @@ mod no_std_stream_tests {
         }
     }
 
-    impl Read for NoStdStream {
+    impl InputStream for NoStdStream {
-        fn read(&mut self, _buf: &mut [u8]) -> Result<usize, StreamError> {
-            unimplemented!()
-        }
-
         fn read_exact(&mut self, buf: &mut [u8]) -> Result<(), StreamError> {
             if self.pos + buf.len() > self.data.len() {
                 unimplemented!();
@@ -94,9 +78,7 @@ mod no_std_stream_tests {
             self.pos += buf.len();
             Ok(())
         }
-    }
 
-    impl Seek for NoStdStream {
         fn seek(&mut self, pos: SeekFrom) -> Result<u64, StreamError> {
             match pos {
                 SeekFrom::End(offset) => {