pe: remove allocation from iteration of mvid; fix some unused warnings; remove unused num_resources from ResoureceEntryIterator

Author: m4b

src/pe/clr.rs

@@ -1,10 +1,5 @@
-use alloc::borrow::Cow;
-use alloc::string::String;
-use alloc::vec::Vec;
 use core::fmt;
 use core::iter::FusedIterator;
-use core::ops::Not;
-use log::debug;
 use scroll::{Pread, Pwrite, SizeWith};
 
 use crate::error;
@@ -13,8 +8,6 @@ use crate::pe::options;
 use crate::pe::section_table;
 use crate::pe::utils;
 
-use super::import::Bitfield;
-
 /// [`ClrData::signature`]: Indicates a valid signature gathered from first 4-bytes of [`Cor20Header::metadata`] (`'BSJB'`)
 pub const DOTNET_SIGNATURE: u32 = 0x424A5342;
 
@@ -147,12 +140,9 @@ impl<'a> ClrData<'a> {
     ///
     /// If this is [`None`] and the [`crate::pe::debug::ReproInfo`] presents, you should use that instead.
     pub fn mvid(&self) -> error::Result<Option<&'a [u8]>> {
-        Ok(self
-            .sections()
-            .collect::<Result<Vec<_>, _>>()?
-            .iter()
-            .find(|x| x.name == "#GUID")
-            .map(|x| {
+        for stream in self.sections() {
+            let x = stream?;
+            if x.name == "#GUID" {
                 let offset = (x.offset as usize)
                     .checked_sub(self.offset_of_metadata)
                     .ok_or_else(|| {
@@ -161,11 +151,14 @@ impl<'a> ClrData<'a> {
                             x.offset, self.offset_of_metadata
                         ))
                     })?;
-                self.metadata_data
+                return self
+                    .metadata_data
                     .pread_with::<&[u8]>(offset, x.size as usize)
                     .map_err(Into::<error::Error>::into)
-            })
-            .transpose()?)
+                    .map(Some);
+            }
+        }
+        Ok(None)
     }
 }
 

src/pe/exception.rs

@@ -54,6 +54,7 @@ use crate::pe::section_table;
 use crate::pe::utils;
 
 /// **N**o handlers.
+#[allow(unused)]
 const UNW_FLAG_NHANDLER: u8 = 0x00;
 /// The function has an exception handler that should be called when looking for functions that need
 /// to examine exceptions.
@@ -1140,21 +1141,21 @@ mod tests {
     const UNWIND_INFO_C_SCOPE_TABLE: &[u8] = &[
         // UNWIND_INFO_HDR
         0x09, 0x0F, 0x06, 0x00,
-    
+
         // UNWIND_CODEs
         0x0F, 0x64,             // UWOP_SAVE_NONVOL (Offset=6, Reg=0x0F)
         0x09, 0x00,
         0x0F, 0x34,             // UWOP_SAVE_NONVOL (Offset=3, Reg=0x0F)
         0x08, 0x00,
         0x0F, 0x52,             // UWOP_ALLOC_SMALL (Size = (2 * 8) + 8 = 24 bytes)
         0x0B, 0x70,             // UWOP_PUSH_NONVOL (Reg=0x0B)
-    
+
         // Exception handler RVA
         0xC0, 0x1F, 0x00, 0x00, // __C_specific_handler
-    
+
         // Scope count
         0x02, 0x00, 0x00, 0x00, // Scope table count = 2
-    
+
         // First C_SCOPE_TABLE entry
         0x01, 0x15, 0x00, 0x00, // BeginAddress   = 0x00001501
         0x06, 0x16, 0x00, 0x00, // EndAddress     = 0x00001606
@@ -1172,21 +1173,21 @@ mod tests {
     const UNWIND_INFO_C_SCOPE_TABLE_INVALID: &[u8] = &[
         // UNWIND_INFO_HDR
         0x09, 0x0F, 0x06, 0x00,
-    
+
         // UNWIND_CODEs
         0x0F, 0x64,             // UWOP_SAVE_NONVOL (Offset=6, Reg=0x0F)
         0x09, 0x00,
         0x0F, 0x34,             // UWOP_SAVE_NONVOL (Offset=3, Reg=0x0F)
         0x08, 0x00,
         0x0F, 0x52,             // UWOP_ALLOC_SMALL (Size = (2 * 8) + 8 = 24 bytes)
         0x0B, 0x70,             // UWOP_PUSH_NONVOL (Reg=0x0B)
-    
+
         // Exception handler RVA
         0xC0, 0x1F, 0x00, 0x00, // __C_specific_handler
-    
+
         // Scope count
         0x02, 0x00, 0x00, 0x00, // Scope table count = 2
-    
+
         // First C_SCOPE_TABLE entry
         0x01, 0x15, 0x00, 0x00, // BeginAddress   = 0x00001501
         0x06, 0x16, 0x00, 0x00, // EndAddress     = 0x00001606

src/pe/resource.rs

@@ -34,19 +34,14 @@ pub(crate) struct Utf16String<'a>(&'a [u8]);
 
 impl<'a> Utf16String<'a> {
     /// Converts underlying bytes into an owned [String].
-    pub fn to_string(&self) -> Option<String> {
+    pub(crate) fn to_string(&self) -> Option<String> {
         to_utf16_string(self.0)
     }
 
     /// Returns the underlying bytes length. This includes null terminator.
-    pub fn len(&self) -> usize {
+    pub(crate) fn len(&self) -> usize {
         self.0.len()
     }
-
-    /// Returns the underlying bytes.
-    pub fn bytes(&self) -> &'a [u8] {
-        self.0
-    }
 }
 
 impl<'a> ctx::TryFromCtx<'a, scroll::Endian> for Utf16String<'a> {
@@ -190,20 +185,13 @@ impl<'a> ImageResourceDirectory {
     ) -> error::Result<ResourceEntryIterator<'a>> {
         let bytes = bytes.pread_with::<&[u8]>(offset, self.entries_size())?;
 
-        Ok(ResourceEntryIterator {
-            num_resources: self.count() as usize,
-            data: bytes,
-        })
+        Ok(ResourceEntryIterator { data: bytes })
     }
 }
 
 /// Iterator over [`ResourceData`]
 #[derive(Debug, Copy, Clone)]
 pub struct ResourceEntryIterator<'a> {
-    /// Total number of ID entries and named entries
-    ///
-    /// Must be equals to [`ImageResourceDirectory::number_of_named_entries`] + [`ImageResourceDirectory::number_of_id_entries`]
-    num_resources: usize,
     /// Raw data of resource direcrory without [`ImageResourceDirectory`] and scoped to [`RESOURCE_ENTRY_SIZE`] * [`Self::num_resources`]
     data: &'a [u8],
 }
@@ -474,7 +462,6 @@ impl<'a> ResourceData<'a> {
                 ))
             })?;
 
-        let count = image_resource_directory.count() as usize;
         let offset = core::mem::size_of::<ImageResourceDirectory>();
         let size = image_resource_directory.entries_size();
         if offset > data.len() {
@@ -486,7 +473,6 @@ impl<'a> ResourceData<'a> {
             error::Error::Malformed(format!("Resource entry offset ({offset:#x}) out of bounds"))
         })?;
         let iterator = ResourceEntryIterator {
-            num_resources: count,
             data: iterator_data,
         };
         let version_info =
@@ -519,7 +505,6 @@ impl<'a> ResourceData<'a> {
         let size = self.image_resource_directory.entries_size();
         // Safety: Panic-free is guaranteed here by Self::parse_with_opts
         ResourceEntryIterator {
-            num_resources: self.count() as usize,
             data: &self.data[offset..offset + size],
         }
     }