chore: replace fmmap with memmap2.

`fmmap` stopped to build with nightly Rust and seems to be unmaintained.

Cargo.toml

@@ -53,7 +53,6 @@ ecdsa = "0.16.9"
 enable-ansi-support = "0.2.1"
 env_logger = "0.11.6"
 figment = "0.10.19"
-fmmap = "0.3.3"
 globwalk = "0.9.1"
 goldenfile = "1.8.0"
 home = "0.5.11"
@@ -69,6 +68,7 @@ log = "0.4.25"
 magic = "0.16.2"
 md2 = "0.10.2"
 md-5 = "0.10.6"
+memmap2 = "0.9.5"
 memchr = "2.7.4"
 memx = "0.1.32"
 nom = "7.1.3"

lib/Cargo.toml

@@ -219,7 +219,7 @@ der-parser = { workspace = true, optional = true, features = ["bigint"] }
 digest = { workspace = true, optional = true }
 dsa = { workspace = true, optional = true }
 ecdsa = { workspace = true, optional = true }
-fmmap = { workspace = true }
+memmap2 = { workspace = true }
 indexmap = { workspace = true, features = ["serde"] }
 intaglio = { workspace = true }
 itertools = { workspace = true }

lib/src/scanner/mod.rs

@@ -18,8 +18,8 @@ use std::time::Duration;
 use std::{cmp, fs, thread};
 
 use bitvec::prelude::*;
-use fmmap::{MmapFile, MmapFileExt};
 use indexmap::IndexMap;
+use memmap2::{Mmap, MmapOptions};
 use protobuf::{CodedInputStream, MessageDyn};
 use rustc_hash::{FxHashMap, FxHashSet};
 use thiserror::Error;
@@ -68,7 +68,7 @@ pub enum ScanError {
         /// Path of the file being scanned.
         path: PathBuf,
         /// Error that occurred.
-        source: fmmap::error::Error,
+        source: std::io::Error,
     },
     /// Could not deserialize the protobuf message for some YARA module.
     #[error("can not deserialize protobuf message for YARA module `{module}`: {err}")]
@@ -97,15 +97,15 @@ static INIT_HEARTBEAT: Once = Once::new();
 pub enum ScannedData<'a> {
     Slice(&'a [u8]),
     Vec(Vec<u8>),
-    Mmap(MmapFile),
+    Mmap(Mmap),
 }
 
 impl AsRef<[u8]> for ScannedData<'_> {
     fn as_ref(&self) -> &[u8] {
         match self {
             ScannedData::Slice(s) => s,
             ScannedData::Vec(v) => v.as_ref(),
-            ScannedData::Mmap(m) => m.as_slice(),
+            ScannedData::Mmap(m) => m.as_ref(),
         }
     }
 }
@@ -569,9 +569,14 @@ impl<'r> Scanner<'r> {
             })?;
             ScannedData::Vec(buffered_file)
         } else {
-            mapped_file = MmapFile::open(path).map_err(|err| {
-                ScanError::MapError { path: path.to_path_buf(), source: err }
-            })?;
+            mapped_file = unsafe {
+                MmapOptions::new().map(&file).map_err(|err| {
+                    ScanError::MapError {
+                        path: path.to_path_buf(),
+                        source: err,
+                    }
+                })
+            }?;
             ScannedData::Mmap(mapped_file)
         };