26.0.1

.idea/.gitignore

@@ -0,0 +1,10 @@
+# Default ignored files
+/shelf/
+/workspace.xml
+# Markdown personal settings
+/markdown.xml
+# Ignored default folder with query files
+/queries/
+# Datasource local storage ignored files
+/dataSources/
+/dataSources.local.xml

.idea/cdrustanoia.iml

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="EMPTY_MODULE" version="4">
+  <component name="NewModuleRootManager">
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/crates/capi-types/src" isTestSource="false" />
+      <sourceFolder url="file://$MODULE_DIR$/crates/cdda-interface/src" isTestSource="false" />
+      <sourceFolder url="file://$MODULE_DIR$/crates/cdda-paranoia/src" isTestSource="false" />
+      <sourceFolder url="file://$MODULE_DIR$/crates/cli/src" isTestSource="false" />
+      <sourceFolder url="file://$MODULE_DIR$/crates/cli/tests" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/crates/core/src" isTestSource="false" />
+      <sourceFolder url="file://$MODULE_DIR$/crates/core/tests" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/crates/core/examples" isTestSource="false" />
+      <excludeFolder url="file://$MODULE_DIR$/target" />
+    </content>
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>

.idea/modules.xml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectModuleManager">
+    <modules>
+      <module fileurl="file://$PROJECT_DIR$/.idea/cdrustanoia.iml" filepath="$PROJECT_DIR$/.idea/cdrustanoia.iml" />
+    </modules>
+  </component>
+</project>

.idea/vcs.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="" vcs="Git" />
+  </component>
+</project>

Cargo.lock

@@ -10,7 +10,7 @@ checksum = "3ded4057c258ba199e2d26386d3af3780957ecaee6c4ef4041c6b4b8b97c0b06"
 
 [[package]]
 name = "cdda_interface"
-version = "0.1.0"
+version = "26.0.1"
 dependencies = [
  "cdrustanoia_capi_types",
  "cdrustanoia_core",
@@ -19,7 +19,7 @@ dependencies = [
 
 [[package]]
 name = "cdda_paranoia"
-version = "0.1.0"
+version = "26.0.1"
 dependencies = [
  "cdda_interface",
  "cdrustanoia_capi_types",
@@ -29,14 +29,14 @@ dependencies = [
 
 [[package]]
 name = "cdrustanoia_capi_types"
-version = "0.1.0"
+version = "26.0.1"
 dependencies = [
  "libc",
 ]
 
 [[package]]
 name = "cdrustanoia_cli"
-version = "0.1.0"
+version = "26.0.1"
 dependencies = [
  "cdrustanoia_core",
  "libc",
@@ -45,7 +45,7 @@ dependencies = [
 
 [[package]]
 name = "cdrustanoia_core"
-version = "0.1.0"
+version = "26.0.1"
 dependencies = [
  "libc",
  "tempfile",

Cargo.toml

@@ -9,7 +9,7 @@ members = [
 ]
 
 [workspace.package]
-version = "0.1.0"
+version = "26.0.1"
 edition = "2021"
 license = "LGPL-2.1-or-later"
 
@@ -20,4 +20,5 @@ cdrustanoia_capi_types = { path = "crates/capi-types" }
 
 [profile.release]
 lto = true
+opt-level = 3
 codegen-units = 1

README.md

@@ -58,6 +58,20 @@ cdrustanoia -r -- "-3" out.raw
 Use `cdrustanoia --help` for the full option and span documentation.  The man
 page is the original cdparanoia man page.
 
+## Benchmarks
+
+The core crate contains a small synthetic benchmark for the paranoia read path
+and the sample index:
+
+```sh
+cargo run --release -p cdrustanoia_core --example bench_paranoia -- 5000
+```
+
+It reports index setup/query times, a comparison with the old `HashMap`
+index, and overall synthetic read throughput.  The image backend is
+memory-backed, so the absolute numbers are useful for regression tracking
+rather than as a prediction of physical drive speed.
+
 ## C API
 
 The two C libraries export the traditional symbols and use the original

crates/cdda-interface/src/lib.rs

@@ -17,6 +17,13 @@ pub struct BackendHolder {
     pub drive: Box<dyn Drive>,
 }
 
+fn ffi_guard<T>(default: T, f: impl FnOnce() -> T) -> T {
+    match std::panic::catch_unwind(std::panic::AssertUnwindSafe(f)) {
+        Ok(value) => value,
+        Err(_) => default,
+    }
+}
+
 unsafe fn cstr(s: &str) -> *mut c_char {
     let clean: String = s.chars().filter(|c| *c != '\0').collect();
     match CString::new(clean) {
@@ -212,6 +219,16 @@ pub unsafe extern "C" fn cdda_identify(
     device: *const c_char,
     messagedest: c_int,
     messages: *mut *mut c_char,
+) -> *mut CdromDrive {
+    ffi_guard(ptr::null_mut(), || {
+        cdda_identify_impl(device, messagedest, messages)
+    })
+}
+
+unsafe fn cdda_identify_impl(
+    device: *const c_char,
+    messagedest: c_int,
+    messages: *mut *mut c_char,
 ) -> *mut CdromDrive {
     if !messages.is_null() {
         *messages = ptr::null_mut();
@@ -234,6 +251,16 @@ pub unsafe extern "C" fn cdda_identify_cooked(
     device: *const c_char,
     messagedest: c_int,
     messages: *mut *mut c_char,
+) -> *mut CdromDrive {
+    ffi_guard(ptr::null_mut(), || {
+        cdda_identify_cooked_impl(device, messagedest, messages)
+    })
+}
+
+unsafe fn cdda_identify_cooked_impl(
+    device: *const c_char,
+    messagedest: c_int,
+    messages: *mut *mut c_char,
 ) -> *mut CdromDrive {
     if !messages.is_null() {
         *messages = ptr::null_mut();
@@ -257,6 +284,17 @@ pub unsafe extern "C" fn cdda_identify_scsi(
     ioctl_device: *const c_char,
     messagedest: c_int,
     messages: *mut *mut c_char,
+) -> *mut CdromDrive {
+    ffi_guard(ptr::null_mut(), || {
+        cdda_identify_scsi_impl(generic_device, ioctl_device, messagedest, messages)
+    })
+}
+
+unsafe fn cdda_identify_scsi_impl(
+    generic_device: *const c_char,
+    ioctl_device: *const c_char,
+    messagedest: c_int,
+    messages: *mut *mut c_char,
 ) -> *mut CdromDrive {
     if !messages.is_null() {
         *messages = ptr::null_mut();
@@ -289,6 +327,15 @@ pub unsafe extern "C" fn cdda_identify_scsi(
 pub unsafe extern "C" fn cdda_find_a_cdrom(
     messagedest: c_int,
     messages: *mut *mut c_char,
+) -> *mut CdromDrive {
+    ffi_guard(ptr::null_mut(), || {
+        cdda_find_a_cdrom_impl(messagedest, messages)
+    })
+}
+
+unsafe fn cdda_find_a_cdrom_impl(
+    messagedest: c_int,
+    messages: *mut *mut c_char,
 ) -> *mut CdromDrive {
     if !messages.is_null() {
         *messages = ptr::null_mut();
@@ -301,6 +348,10 @@ pub unsafe extern "C" fn cdda_find_a_cdrom(
 
 #[no_mangle]
 pub unsafe extern "C" fn cdda_open(d: *mut CdromDrive) -> c_int {
+    ffi_guard(-100, || cdda_open_impl(d))
+}
+
+unsafe fn cdda_open_impl(d: *mut CdromDrive) -> c_int {
     if d.is_null() {
         return -100;
     }
@@ -343,6 +394,10 @@ pub unsafe extern "C" fn cdda_open(d: *mut CdromDrive) -> c_int {
 
 #[no_mangle]
 pub unsafe extern "C" fn cdda_close(d: *mut CdromDrive) -> c_int {
+    ffi_guard(0, || cdda_close_impl(d))
+}
+
+unsafe fn cdda_close_impl(d: *mut CdromDrive) -> c_int {
     if d.is_null() {
         return 0;
     }
@@ -357,6 +412,18 @@ pub unsafe extern "C" fn cdda_read_timed(
     beginsector: c_long,
     sectors: c_long,
     ms: *mut c_int,
+) -> c_long {
+    ffi_guard(-1, || {
+        cdda_read_timed_impl(d, buffer, beginsector, sectors, ms)
+    })
+}
+
+unsafe fn cdda_read_timed_impl(
+    d: *mut CdromDrive,
+    buffer: *mut c_void,
+    beginsector: c_long,
+    sectors: c_long,
+    ms: *mut c_int,
 ) -> c_long {
     if !ms.is_null() {
         *ms = -1;
@@ -422,6 +489,10 @@ pub unsafe extern "C" fn cdda_read(
 
 #[no_mangle]
 pub unsafe extern "C" fn cdda_speed_set(d: *mut CdromDrive, speed: c_int) -> c_int {
+    ffi_guard(-405, || cdda_speed_set_impl(d, speed))
+}
+
+unsafe fn cdda_speed_set_impl(d: *mut CdromDrive, speed: c_int) -> c_int {
     match holder(d) {
         Some(h) => {
             let ret = h.drive.speed_set(speed);
@@ -569,3 +640,81 @@ pub unsafe extern "C" fn cdda_track_bitmap(
 // Keep the c_long import used on all targets.
 #[allow(dead_code)]
 fn _typecheck(_: c_long) {}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use cdrustanoia_core::device::{DiscToc, InterfaceKind, ReadError, TimedRead};
+
+    struct PanicDrive {
+        toc: DiscToc,
+    }
+
+    impl Drive for PanicDrive {
+        fn toc(&self) -> &DiscToc {
+            &self.toc
+        }
+        fn toc_mut(&mut self) -> &mut DiscToc {
+            &mut self.toc
+        }
+        fn opened(&self) -> bool {
+            false
+        }
+        fn open_disc(&mut self) -> Result<(), String> {
+            panic!("intentional test panic");
+        }
+        fn read_audio(
+            &mut self,
+            _buffer: Option<&mut [u8]>,
+            _begin: i64,
+            _sectors: i64,
+        ) -> Result<usize, ReadError> {
+            Err(ReadError::closed())
+        }
+        fn read_timed(
+            &mut self,
+            _buffer: Option<&mut [u8]>,
+            _begin: i64,
+            _sectors: i64,
+        ) -> TimedRead {
+            TimedRead {
+                result: Err(ReadError::closed()),
+                milliseconds: -1,
+            }
+        }
+        fn speed_set(&mut self, _speed: i32) -> i32 {
+            -405
+        }
+        fn close(&mut self) {}
+        fn drive_model(&self) -> &str {
+            "panic drive"
+        }
+        fn bigendianp(&self) -> i32 {
+            0
+        }
+        fn set_bigendianp(&mut self, _value: i32) {}
+        fn nsectors(&self) -> i64 {
+            1
+        }
+        fn set_nsectors(&mut self, _value: i64) {}
+        fn interface(&self) -> InterfaceKind {
+            InterfaceKind::SgIo
+        }
+    }
+
+    #[test]
+    fn c_api_catches_panics() {
+        unsafe {
+            let d = make_drive(
+                "panic",
+                None,
+                Box::new(PanicDrive {
+                    toc: DiscToc::default(),
+                }),
+            );
+            assert!(!d.is_null());
+            assert_eq!(cdda_open(d), -100);
+            assert_eq!(cdda_close(d), 0);
+        }
+    }
+}

crates/cdda-paranoia/src/lib.rs

@@ -19,6 +19,13 @@ use std::time::Instant;
 
 pub type ParanoiaCallback = Option<unsafe extern "C" fn(c_long, c_int)>;
 
+fn ffi_guard<T>(default: T, f: impl FnOnce() -> T) -> T {
+    match std::panic::catch_unwind(std::panic::AssertUnwindSafe(f)) {
+        Ok(value) => value,
+        Err(_) => default,
+    }
+}
+
 struct CAbiDrive {
     d: *mut CdromDrive,
     toc: DiscToc,
@@ -190,6 +197,10 @@ pub unsafe extern "C" fn paranoia_version() -> *const c_char {
 
 #[no_mangle]
 pub unsafe extern "C" fn paranoia_init(d: *mut CdromDrive) -> *mut c_void {
+    ffi_guard(ptr::null_mut(), || paranoia_init_impl(d))
+}
+
+unsafe fn paranoia_init_impl(d: *mut CdromDrive) -> *mut c_void {
     if d.is_null() {
         return ptr::null_mut();
     }
@@ -201,6 +212,10 @@ pub unsafe extern "C" fn paranoia_init(d: *mut CdromDrive) -> *mut c_void {
 
 #[no_mangle]
 pub unsafe extern "C" fn paranoia_free(p: *mut c_void) {
+    ffi_guard((), || paranoia_free_impl(p))
+}
+
+unsafe fn paranoia_free_impl(p: *mut c_void) {
     if !p.is_null() {
         drop(Box::from_raw(p as *mut Paranoia));
     }
@@ -246,6 +261,16 @@ pub unsafe extern "C" fn paranoia_read_limited(
     p: *mut c_void,
     callback: ParanoiaCallback,
     max_retries: c_int,
+) -> *mut i16 {
+    ffi_guard(ptr::null_mut(), || {
+        paranoia_read_limited_impl(p, callback, max_retries)
+    })
+}
+
+unsafe fn paranoia_read_limited_impl(
+    p: *mut c_void,
+    callback: ParanoiaCallback,
+    max_retries: c_int,
 ) -> *mut i16 {
     let p = match p_ref(p) {
         Some(p) => p,

crates/cli/src/lib.rs

@@ -22,19 +22,20 @@ use std::os::unix::fs::OpenOptionsExt;
 use std::os::unix::io::FromRawFd;
 use std::path::Path;
 
-const MANUAL: &str = r#"cdparanoia III release 10.2 (September 11, 2008)
+const MANUAL: &str = r#"cdrustanoia 26.0.1 (2026-11-03)
+based on the great cdparanoia by Monty <monty@xiph.org> and Xiph.Org
 
-(C) 2008 Monty <monty@xiph.org> and Xiph.Org
+(C) 2026 Martin Wohlert <martin.wohlert@b-root-force.de>
+
+Report bugs to martin.wohlert@b-root-force.de
 
-Report bugs to paranoia@xiph.org
-http://www.xiph.org/paranoia/
 USAGE:
-  cdparanoia [options] <span> [outfile]
+  cdrustanoia [options] <span> [outfile]
 
 OPTIONS:
   -A --analyze-drive              : run and log a complete analysis of drive
                                     caching, timing and reading behavior;
-                                    verifies that cdparanoia is correctly
+                                    verifies that cdrustanoia is correctly
                                     modelling a sprcific drive's cache and
                                     read behavior. Implies -vQL
   -v --verbose                    : extra verbose operation
@@ -42,10 +43,10 @@ OPTIONS:
   -e --stderr-progress            : force output of progress information to
                                     stderr (for wrapper scripts)
   -l --log-summary [<file>]       : save result summary to file, default
-                                    filename cdparanoia.log
+                                    filename cdrustanoia.log
   -L --log-debug   [<file>]       : save detailed device autosense and
                                     debugging output to file, default
-                                    filename cdparanoia.log
+                                    filename cdrustanoia.log
   -V --version                    : print version info and quit
   -Q --query                      : autosense drive, query disc and quit
   -B --batch                      : 'batch' mode (saves each track to a
@@ -77,7 +78,7 @@ OPTIONS:
                                     force use of the old SG kernel
                                     interface. -g cannot be used with -k.
   -S --force-read-speed <n>       : read from device at specified speed; by
-                                    default, cdparanoia sets drive to full
+                                    default, cdrustanoia sets drive to full
                                     speed.
   -t --toc-offset <n>             : Add <n> sectors to the values reported
                                     when addressing tracks. May be negative
@@ -154,16 +155,14 @@ the shell...
 A few examples, protected from the shell:
   A) query only with exhaustive search for a drive and full reporting
      of autosense:
-       cdparanoia -vsQ
+       cdrustanoia -vsQ
 
   B) extract up to and including track 3, putting each track in a seperate
      file:
-       cdparanoia -B -- "-3"
+       cdrustanoia -B -- "-3"
 
   C) extract from track 1, time 0:30.12 to 1:10.00:
-       cdparanoia "1[:30.12]-1[1:10]"
-
-Submit bug reports to paranoia@xiph.org
+       cdrustanoia "1[:30.12]-1[1:10]"
 
 "#;
 
@@ -283,17 +282,6 @@ fn display_toc(d: &dyn Drive, log: &mut Log) {
     log.report(format_args!(" "));
 }
 
-fn read_sector(
-    p: &mut Paranoia,
-    progress: &mut Progress,
-    log: &mut Log,
-    max_retries: i32,
-) -> Option<Vec<i16>> {
-    let mut callback = |pos: i64, func: i32| progress.callback(pos, func, log);
-    p.read_limited(&mut callback, max_retries)
-        .map(|s| s.to_vec())
-}
-
 fn samples_as_bytes(samples: &[i16]) -> &[u8] {
     unsafe {
         std::slice::from_raw_parts(
@@ -708,7 +696,11 @@ of the machine.\n\nMore information about /dev/cdrom:"
 
         progress.skipped_flag = false;
         while cursor <= batch_last {
-            let sector = match read_sector(&mut p, &mut progress, &mut log, args.max_retries) {
+            let sector = {
+                let mut callback = |pos: i64, func: i32| progress.callback(pos, func, &mut log);
+                p.read_limited(&mut callback, args.max_retries)
+            };
+            let data = match sector {
                 Some(s) => s,
                 None => {
                     progress.skipped_flag = true;
@@ -725,23 +717,32 @@ of the machine.\n\nMore information about /dev/cdrom:"
             progress.skipped_flag = false;
             cursor += 1;
 
-            let mut data = sector;
             if target_big != host_big {
-                for s in &mut data {
+                for s in data.iter_mut() {
                     *s = swap16(*s);
                 }
             }
             progress.callback(cursor * 1176 - 1, -2, &mut log);
 
-            let data_bytes = samples_as_bytes(&data);
+            let data_bytes = samples_as_bytes(data);
             if let Err(e) = out.write_all(&data_bytes[offset_skip.min(data_bytes.len())..]) {
                 log.report(format_args!("Error writing output: {}", e));
                 return 1;
             }
             offset_skip = 0;
 
+            if target_big != host_big {
+                for s in data.iter_mut() {
+                    *s = swap16(*s);
+                }
+            }
+
             if sample_offset != 0 && cursor > batch_last {
-                let extra = match read_sector(&mut p, &mut progress, &mut log, args.max_retries) {
+                let extra = {
+                    let mut callback = |pos: i64, func: i32| progress.callback(pos, func, &mut log);
+                    p.read_limited(&mut callback, args.max_retries)
+                };
+                let extra = match extra {
                     Some(s) => s,
                     None => {
                         progress.skipped_flag = true;
@@ -756,14 +757,18 @@ of the machine.\n\nMore information about /dev/cdrom:"
                     break;
                 }
                 progress.skipped_flag = false;
-                let mut extra = extra;
                 if target_big != host_big {
-                    for s in &mut extra {
+                    for s in extra.iter_mut() {
                         *s = swap16(*s);
                     }
                 }
-                let eb = samples_as_bytes(&extra);
+                let eb = samples_as_bytes(extra);
                 offset_buffer[..eb.len().min(2352)].copy_from_slice(&eb[..eb.len().min(2352)]);
+                if target_big != host_big {
+                    for s in extra.iter_mut() {
+                        *s = swap16(*s);
+                    }
+                }
                 offset_buffer_used = (sample_offset as usize * 4).min(2352);
                 progress.callback(cursor * 1176, -2, &mut log);
                 if let Err(e) = out.write_all(&offset_buffer[..offset_buffer_used]) {

crates/core/Cargo.toml

@@ -3,6 +3,7 @@ name = "cdrustanoia_core"
 version.workspace = true
 edition.workspace = true
 license = "LGPL-2.1-or-later"
+publish = false
 
 [dependencies]
 libc.workspace = true

crates/core/examples/bench_paranoia.rs

@@ -0,0 +1,168 @@
+//! Small benchmark harness for the paranoia read path and sample index.
+//!
+//! Run with:
+//!   cargo run --release --example bench_paranoia
+//!   cargo run --release --example bench_paranoia -- 5000
+
+use cdrustanoia_core::device::image::ImageDrive;
+use cdrustanoia_core::device::samples_to_bytes;
+use cdrustanoia_core::paranoia::sort::SortIndex;
+use cdrustanoia_core::paranoia::{Paranoia, PARANOIA_MODE_FULL};
+use std::collections::HashMap;
+use std::time::Instant;
+
+fn make_samples(sectors: usize) -> Vec<i16> {
+    let mut out = Vec::with_capacity(sectors * 1176);
+    let mut x = 0x1234_5678_9abc_def0u64;
+    for i in 0..sectors * 1176 {
+        x ^= x << 13;
+        x ^= x >> 7;
+        x ^= x << 17;
+        let v = if i % 5000 < 700 {
+            0
+        } else {
+            (x as i16).wrapping_add((i as i16).wrapping_mul(11))
+        };
+        out.push(v);
+    }
+    out
+}
+
+fn bench_index(samples: &[i16]) {
+    let mut index = SortIndex::new(samples.len());
+    let started = Instant::now();
+    index.setup(samples, 0, 0, samples.len() as i64);
+    let setup = started.elapsed();
+
+    let mut found = 0usize;
+    let started = Instant::now();
+    for i in 0..10_000i64 {
+        let post = (i * 7919) % samples.len() as i64;
+        let value = samples[post as usize];
+        if index.getmatch(samples, post, 512, value).is_some() {
+            found += 1;
+            while index.nextmatch(samples).is_some() {
+                found += 1;
+            }
+        }
+    }
+    let queries = started.elapsed();
+    println!(
+        "SortIndex: setup={:?} 10k queries={:?} matches={} ({} samples)",
+        setup,
+        queries,
+        found,
+        samples.len()
+    );
+}
+
+struct OldIndex {
+    buckets: HashMap<i16, Vec<u32>>,
+    size: usize,
+    cursor: Option<(i16, usize, usize)>,
+}
+
+impl OldIndex {
+    fn new() -> Self {
+        Self {
+            buckets: HashMap::new(),
+            size: 0,
+            cursor: None,
+        }
+    }
+    fn setup(&mut self, samples: &[i16]) {
+        self.buckets.clear();
+        self.size = samples.len();
+        for (i, &sample) in samples.iter().enumerate() {
+            self.buckets.entry(sample).or_default().push(i as u32);
+        }
+    }
+    fn getmatch(&mut self, post: i64, overlap: i64, value: i16) -> Option<usize> {
+        let post = post.clamp(0, self.size as i64);
+        let lo = (post - overlap).max(0) as usize;
+        let hi = ((post + overlap).min(self.size as i64)).max(0) as usize;
+        self.cursor = None;
+        let positions = self.buckets.get(&value)?;
+        let idx = positions.partition_point(|p| (*p as usize) < lo);
+        if idx >= positions.len() {
+            return None;
+        }
+        let pos = positions[idx] as usize;
+        if pos >= hi {
+            return None;
+        }
+        self.cursor = Some((value, idx + 1, hi));
+        Some(pos)
+    }
+    fn nextmatch(&mut self) -> Option<usize> {
+        let (value, idx, hi) = self.cursor?;
+        let positions = self.buckets.get(&value)?;
+        if idx >= positions.len() {
+            self.cursor = None;
+            return None;
+        }
+        let pos = positions[idx] as usize;
+        if pos >= hi {
+            self.cursor = None;
+            return None;
+        }
+        self.cursor = Some((value, idx + 1, hi));
+        Some(pos)
+    }
+}
+
+fn bench_old_index(samples: &[i16]) {
+    let mut index = OldIndex::new();
+    let started = Instant::now();
+    index.setup(samples);
+    let setup = started.elapsed();
+    let mut found = 0usize;
+    let started = Instant::now();
+    for i in 0..10_000i64 {
+        let post = (i * 7919) % samples.len() as i64;
+        let value = samples[post as usize];
+        if index.getmatch(post, 512, value).is_some() {
+            found += 1;
+            while index.nextmatch().is_some() {
+                found += 1;
+            }
+        }
+    }
+    let queries = started.elapsed();
+    println!(
+        "Old HashMap index: setup={:?} 10k queries={:?} matches={}",
+        setup, queries, found
+    );
+}
+
+fn main() {
+    let sectors: usize = std::env::args()
+        .nth(1)
+        .and_then(|s| s.parse().ok())
+        .unwrap_or(2000);
+    let samples = make_samples(sectors);
+    bench_index(&samples);
+    bench_old_index(&samples);
+
+    let bytes = samples_to_bytes(&samples);
+    let drive = ImageDrive::from_bytes(bytes);
+    let mut p = Paranoia::new(Box::new(drive));
+    p.modeset(PARANOIA_MODE_FULL);
+    let mut cb = |_: i64, _: i32| {};
+    let started = Instant::now();
+    let mut got = 0usize;
+    for _ in 0..sectors {
+        let sector = p.read(&mut cb).expect("read sector");
+        got += sector.len();
+    }
+    let elapsed = started.elapsed();
+    let bytes_read = (got * 2) as f64;
+    println!(
+        "Read: {} sectors, {} samples, {:?}, {:.1} MB/s",
+        sectors,
+        got,
+        elapsed,
+        bytes_read / elapsed.as_secs_f64() / 1_000_000.0
+    );
+    assert_eq!(got, sectors * 1176);
+}

crates/core/src/device/image.rs

@@ -192,7 +192,13 @@ impl ImageDrive {
 
     fn read_words(&mut self, begin_sector: i64, sectors: i64) -> Vec<i16> {
         let words = sectors.max(0) * CD_FRAMEWORDS;
-        let mut out = Vec::with_capacity(words as usize);
+        let mut out = vec![0i16; words as usize];
+        self.read_words_into(begin_sector, sectors, &mut out);
+        out
+    }
+
+    fn read_words_into(&mut self, begin_sector: i64, sectors: i64, out: &mut [i16]) {
+        let words = sectors.max(0) * CD_FRAMEWORDS;
         let mut jitter = 0i64;
         if self.faults.jitter_words > 0 {
             self.read_count = self.read_count.wrapping_add(1);
@@ -211,10 +217,9 @@ impl ImageDrive {
             }
         }
         let start = begin_sector * CD_FRAMEWORDS + jitter;
-        for w in 0..words {
-            out.push(self.mapped_sample(start + w).unwrap_or(0));
+        for (w, slot) in out.iter_mut().enumerate().take(words as usize) {
+            *slot = self.mapped_sample(start + w as i64).unwrap_or(0);
         }
-        out
     }
 }
 
@@ -281,6 +286,32 @@ impl Drive for ImageDrive {
         self.last_begin = begin;
         Ok(sectors as usize)
     }
+    fn read_audio_samples(
+        &mut self,
+        buffer: &mut [i16],
+        begin: i64,
+        sectors: i64,
+    ) -> Result<usize, ReadError> {
+        if !self.opened {
+            return Err(ReadError::closed());
+        }
+        if sectors <= 0 {
+            return Ok(0);
+        }
+        let mut sectors = sectors;
+        if self.faults.max_read_sectors > 0 {
+            sectors = sectors.min(self.faults.max_read_sectors);
+        }
+        let out_len = (sectors * CD_FRAMEWORDS) as usize;
+        self.read_words_into(begin, sectors, buffer);
+        if super::host_big_endian() {
+            for sample in buffer.iter_mut().take(out_len) {
+                *sample = super::swap16(*sample);
+            }
+        }
+        self.last_begin = begin;
+        Ok(sectors as usize)
+    }
     fn read_timed(&mut self, buffer: Option<&mut [u8]>, begin: i64, sectors: i64) -> TimedRead {
         let start = Instant::now();
         let previous_begin = self.last_begin;

crates/core/src/device/linux.rs

@@ -178,6 +178,7 @@ pub struct LinuxDrive {
     fua: bool,
     read_cmd: ReadCommand,
     enable_mode: EnableMode,
+    last_milliseconds: i32,
 }
 
 impl LinuxDrive {
@@ -199,6 +200,7 @@ impl LinuxDrive {
             fua: false,
             read_cmd: ReadCommand::D8,
             enable_mode: EnableMode::Dummy,
+            last_milliseconds: 0,
         };
         d.inquiry()?;
         d.check_atapi();
@@ -238,6 +240,7 @@ impl LinuxDrive {
             fua: false,
             read_cmd: ReadCommand::Read28,
             enable_mode: EnableMode::Dummy,
+            last_milliseconds: 0,
         };
         Ok(d)
     }
@@ -561,7 +564,9 @@ impl LinuxDrive {
             duration: 0,
             info: 0,
         };
+        let started = Instant::now();
         let rc = unsafe { libc::ioctl(self.fd, SG_IO, &mut hdr as *mut SgIoHdr) };
+        self.last_milliseconds = started.elapsed().as_millis() as i32;
         if rc < 0 {
             return Err(ScsiError::io(io::Error::last_os_error()));
         }
@@ -819,7 +824,9 @@ impl LinuxDrive {
                 nframes: requested as c_int,
                 buf: buf.as_mut_ptr(),
             };
+            let started = Instant::now();
             let rc = unsafe { libc::ioctl(self.fd, CDROMREADAUDIO, &mut arg as *mut _) };
+            self.last_milliseconds = started.elapsed().as_millis() as i32;
             if rc == 0 {
                 return Ok(requested as usize);
             }
@@ -1211,12 +1218,11 @@ impl Drive for LinuxDrive {
         self.read_raw(buffer, begin, sectors)
     }
     fn read_timed(&mut self, buffer: Option<&mut [u8]>, begin: i64, sectors: i64) -> TimedRead {
-        let started = Instant::now();
+        self.last_milliseconds = -1;
         let result = self.read_audio(buffer, begin, sectors);
-        let elapsed = started.elapsed().as_millis() as i32;
         TimedRead {
             result,
-            milliseconds: elapsed,
+            milliseconds: self.last_milliseconds,
         }
     }
     fn speed_set(&mut self, speed: i32) -> i32 {

crates/core/src/device/mod.rs

@@ -275,6 +275,31 @@ pub trait Drive {
         begin: i64,
         sectors: i64,
     ) -> Result<usize, ReadError>;
+
+    /// Read audio directly into a host-endian `i16` buffer.
+    ///
+    /// This is a byte-view over the same memory; it lets the paranoia engine
+    /// read straight into the `CBlock` vector without an intermediate
+    /// `Vec<u8>` plus `bytes_to_samples()` copy.  Implementations of
+    /// `read_audio()` already promise host endian PCM data.
+    fn read_audio_samples(
+        &mut self,
+        buffer: &mut [i16],
+        begin: i64,
+        sectors: i64,
+    ) -> Result<usize, ReadError> {
+        // SAFETY: `i16` has no padding and the byte view covers exactly the
+        // initialized elements of `buffer`.  The view lives only for this
+        // call, and all bytes are written by the backend before it returns.
+        let bytes = unsafe {
+            std::slice::from_raw_parts_mut(
+                buffer.as_mut_ptr().cast::<u8>(),
+                std::mem::size_of_val(buffer),
+            )
+        };
+        self.read_audio(Some(bytes), begin, sectors)
+    }
+
     /// Low-level read without host-endian conversion, matching the original
     /// `cdrom_drive::read_audio` function pointer.
     fn read_audio_raw(

crates/core/src/lib.rs

@@ -15,8 +15,8 @@ pub mod callback;
 pub mod device;
 pub mod paranoia;
 
-pub const VERSIONNUM: &str = "10.2";
-pub const VERSION: &str = "cdparanoia III release 10.2 (September 11, 2008)";
+pub const VERSIONNUM: &str = "26.0.1";
+pub const VERSION: &str = "cdrustanoia 26.0.1 (2026-11-03)";
 
 pub fn paranoia_version() -> &'static str {
     VERSIONNUM

crates/core/src/paranoia/block.rs

@@ -1,12 +1,14 @@
 //! c_block/v_fragment/root data structures and vector operations.
 
+use std::sync::Arc;
+
 pub const FLAGS_EDGE: u8 = 0x1;
 pub const FLAGS_UNREAD: u8 = 0x2;
 pub const FLAGS_VERIFIED: u8 = 0x4;
 
 #[derive(Clone, Debug)]
 pub struct CBlock {
-    pub vector: Vec<i16>,
+    pub vector: Arc<Vec<i16>>,
     pub flags: Option<Vec<u8>>,
     pub begin: i64,
     pub size: i64,
@@ -22,7 +24,7 @@ impl Default for CBlock {
 impl CBlock {
     pub fn new() -> Self {
         Self {
-            vector: Vec::new(),
+            vector: Arc::new(Vec::new()),
             flags: None,
             begin: 0,
             size: 0,
@@ -33,7 +35,7 @@ impl CBlock {
     pub fn from_parts(vector: Vec<i16>, begin: i64, lastsector: bool) -> Self {
         let size = vector.len() as i64;
         Self {
-            vector,
+            vector: Arc::new(vector),
             flags: None,
             begin,
             size,
@@ -62,7 +64,7 @@ impl CBlock {
             return;
         }
         let pos = pos as usize;
-        self.vector.splice(pos..pos, data.iter().copied());
+        Arc::make_mut(&mut self.vector).splice(pos..pos, data.iter().copied());
         self.size += data.len() as i64;
         if let Some(flags) = self.flags.as_mut() {
             let n = data.len();
@@ -87,7 +89,7 @@ impl CBlock {
         }
         let pos = cutpos as usize;
         let n = cutsize as usize;
-        self.vector.drain(pos..pos + n);
+        Arc::make_mut(&mut self.vector).drain(pos..pos + n);
         self.size -= cutsize;
         if let Some(flags) = self.flags.as_mut() {
             let pos = pos.min(flags.len());
@@ -109,11 +111,11 @@ impl CBlock {
         }
         let p = pos as usize;
         let n = size as usize;
-        self.vector[p..p + n].copy_from_slice(&data[..n]);
+        Arc::make_mut(&mut self.vector)[p..p + n].copy_from_slice(&data[..n]);
     }
 
     pub fn append(&mut self, data: &[i16]) {
-        self.vector.extend_from_slice(data);
+        Arc::make_mut(&mut self.vector).extend_from_slice(data);
         self.size += data.len() as i64;
         if let Some(flags) = self.flags.as_mut() {
             flags.extend(std::iter::repeat_n(0, data.len()));
@@ -125,7 +127,7 @@ impl CBlock {
             return;
         }
         let n = (cut as usize).min(self.vector.len());
-        self.vector.drain(..n);
+        Arc::make_mut(&mut self.vector).drain(..n);
         self.size -= n as i64;
         self.begin += n as i64;
         if let Some(flags) = self.flags.as_mut() {
@@ -148,7 +150,10 @@ impl CBlock {
 
 #[derive(Clone, Debug)]
 pub struct VFragment {
-    pub vector: Vec<i16>,
+    /// Shared backing data.  Cache blocks and all fragments carved from them
+    /// reference the same allocation; no per-fragment copy is made.
+    pub data: Arc<Vec<i16>>,
+    pub offset: usize,
     pub begin: i64,
     pub size: i64,
     pub lastsector: bool,
@@ -158,6 +163,10 @@ impl VFragment {
     pub fn end(&self) -> i64 {
         self.begin + self.size
     }
+
+    pub fn vector(&self) -> &[i16] {
+        &self.data[self.offset..self.offset + self.size as usize]
+    }
 }
 
 #[derive(Clone, Debug, Default)]

crates/core/src/paranoia/mod.rs

@@ -8,6 +8,7 @@ use crate::device::{Drive, CD_FRAMESIZE_RAW, CD_FRAMEWORDS};
 use block::*;
 use sort::SortIndex;
 use std::collections::VecDeque;
+use std::sync::Arc;
 
 pub const MIN_WORDS_OVERLAP: i64 = 64;
 pub const MIN_WORDS_SEARCH: i64 = 64;
@@ -61,6 +62,8 @@ pub struct Paranoia {
     pub dynoverlap: i64,
     pub dyndrift: i64,
     stage2_adjust_pending: bool,
+    sample_pool: Vec<Vec<i16>>,
+    flag_pool: Vec<Vec<u8>>,
 }
 
 // ---------------------------------------------------------------------------
@@ -329,7 +332,7 @@ fn try_sort_sync(
     // Search for a matching sample within dynoverlap.
     let search_post = post - a_begin;
     if sort
-        .getmatch(search_post, *dynoverlap, b.vector[b_idx as usize])
+        .getmatch(a_vector, search_post, *dynoverlap, b.vector[b_idx as usize])
         .is_some()
     {
         loop {
@@ -356,7 +359,7 @@ fn try_sort_sync(
                 *end = bend;
                 return true;
             }
-            if !sort.advance() {
+            if !sort.advance(a_vector) {
                 break;
             }
         }
@@ -732,7 +735,7 @@ fn iterate_stage2(
     callback(v.begin, PARANOIA_CB_VERIFY);
 
     let mut fbv = v.begin.max(root.begin - *dynoverlap);
-    while fbv < v.end() && v.vector[(fbv - v.begin) as usize] == 0 {
+    while fbv < v.end() && v.vector()[(fbv - v.begin) as usize] == 0 {
         fbv += 1;
     }
     if fbv == v.end() {
@@ -744,7 +747,7 @@ fn iterate_stage2(
         .min(v.end());
     let searchend = (fev + *dynoverlap).min(root.end());
     let searchbegin = (fbv - *dynoverlap).max(root.begin);
-    sort.setup(&v.vector, v.begin, fbv, fev);
+    sort.setup(v.vector(), v.begin, fbv, fev);
 
     let mut j = searchbegin;
     while j < searchend {
@@ -759,7 +762,7 @@ fn iterate_stage2(
         let mut offset = 0;
         if try_sort_sync(
             sort,
-            &v.vector,
+            v.vector(),
             v.begin,
             v.size,
             None,
@@ -827,7 +830,7 @@ fn silence_match(
         return false;
     }
     let mut j = 0;
-    while j < end && v.vector[j as usize] == 0 {
+    while j < end && v.vector()[j as usize] == 0 {
         j += 1;
     }
     if j < MIN_SILENCE_BOUNDARY {
@@ -849,7 +852,7 @@ fn silence_match(
         if v.end() > root.end() {
             let voff = begin - v.begin;
             root.remove(begin - root.begin, root.size - (begin - root.begin));
-            root.append(&v.vector[voff as usize..]);
+            root.append(&v.vector()[voff as usize..]);
         }
         add_stage2_value(stage2, 0, stage2_pending);
     } else if j < begin {
@@ -859,7 +862,7 @@ fn silence_match(
                 *silence_begin - root.begin,
                 root.size - (*silence_begin - root.begin),
             );
-            root.append(&v.vector[voff as usize..]);
+            root.append(&v.vector()[voff as usize..]);
         }
         add_stage2_value(stage2, end - begin, stage2_pending);
     } else {
@@ -907,7 +910,7 @@ fn stage2_each(
     callback: &mut dyn FnMut(i64, i32),
 ) -> MergeOutcome {
     let dyno = *dynoverlap / 2 * 2;
-    if v.size <= 0 || v.vector.is_empty() {
+    if v.size <= 0 || v.vector().is_empty() {
         return MergeOutcome::Discarded;
     }
 
@@ -931,7 +934,11 @@ fn stage2_each(
     while begin + offset > 0 && begin > 0 {
         let begin_l = begin + offset;
         if scratch.is_none() {
-            scratch = Some(CBlock::from_parts(v.vector.clone(), v.begin, v.lastsector));
+            scratch = Some(CBlock::from_parts(
+                v.vector().to_vec(),
+                v.begin,
+                v.lastsector,
+            ));
         }
         let (mut match_a, mut match_b, mut match_c) = (0, 0, 0);
         {
@@ -1021,7 +1028,11 @@ fn stage2_each(
         let begin_l = begin + offset;
         let end_l = end + offset;
         if scratch.is_none() {
-            scratch = Some(CBlock::from_parts(v.vector.clone(), v.begin, v.lastsector));
+            scratch = Some(CBlock::from_parts(
+                v.vector().to_vec(),
+                v.begin,
+                v.lastsector,
+            ));
         }
         let (mut match_a, mut match_b, mut match_c) = (0, 0, 0);
         {
@@ -1130,7 +1141,7 @@ fn stage2_each(
         }
         let data: Vec<i16> = match scratch.as_ref() {
             Some(l) => l.vector[(end + offset) as usize..size_b as usize].to_vec(),
-            None => v.vector[(end + offset) as usize..size_b as usize].to_vec(),
+            None => v.vector()[(end + offset) as usize..size_b as usize].to_vec(),
         };
         if !data.is_empty() {
             root.append(&data);
@@ -1183,6 +1194,8 @@ impl Paranoia {
             dynoverlap: MAX_SECTOR_OVERLAP * CD_FRAMEWORDS,
             dyndrift: 0,
             stage2_adjust_pending: false,
+            sample_pool: Vec::new(),
+            flag_pool: Vec::new(),
         };
         p.firstlast();
         p
@@ -1212,6 +1225,41 @@ impl Paranoia {
         ret
     }
 
+    fn take_sample_buf(&mut self, len: usize) -> Vec<i16> {
+        let mut buf = self.sample_pool.pop().unwrap_or_default();
+        buf.clear();
+        buf.resize(len, 0);
+        buf
+    }
+
+    fn take_flag_buf(&mut self, len: usize) -> Vec<u8> {
+        let mut buf = self.flag_pool.pop().unwrap_or_default();
+        buf.clear();
+        buf.resize(len, 0);
+        buf
+    }
+
+    fn recycle_block(&mut self, mut block: CBlock) {
+        if let Some(mut flags) = block.flags.take() {
+            if self.flag_pool.len() < 2 {
+                flags.clear();
+                self.flag_pool.push(flags);
+            }
+        }
+        if let Ok(mut vector) = Arc::try_unwrap(block.vector) {
+            if self.sample_pool.len() < 2 {
+                vector.clear();
+                self.sample_pool.push(vector);
+            }
+        }
+    }
+
+    fn recycle_root(&mut self) {
+        if let Some(block) = self.root.vector.take() {
+            self.recycle_block(block);
+        }
+    }
+
     fn firstlast(&mut self) {
         let tracks = self.d.tracks();
         let curtrack = self.d.sector_gettrack(self.cursor);
@@ -1249,7 +1297,7 @@ impl Paranoia {
         if self.d.sector_gettrack(sector) < 0 {
             return -1;
         }
-        self.root.vector = None;
+        self.recycle_root();
         self.root.lastsector = false;
         self.root.returned_limit = 0;
         self.root.silence_flag = false;
@@ -1264,19 +1312,23 @@ impl Paranoia {
         self.root.returned_limit = 0;
         self.dyndrift = 0;
         self.root.lastsector = false;
-        self.root.vector = None;
+        self.recycle_root();
         self.root.silence_flag = false;
         self.resetcache();
     }
 
     fn resetcache(&mut self) {
-        self.cache.clear();
         self.fragments.clear();
+        while let Some(block) = self.cache.pop_front() {
+            self.recycle_block(block);
+        }
     }
 
     fn recover_cache(&mut self) {
         while self.cache.len() > self.cache_limit {
-            self.cache.pop_back();
+            if let Some(block) = self.cache.pop_back() {
+                self.recycle_block(block);
+            }
         }
     }
 
@@ -1338,7 +1390,7 @@ impl Paranoia {
         beginword: i64,
         _endword: i64,
         callback: &mut dyn FnMut(i64, i32),
-    ) -> Option<CBlock> {
+    ) -> bool {
         let totaltoread = self.cdcache_size;
         let sectatonce = self.d.nsectors().max(1);
         let driftcomp = (self.dyndrift as f64 / CD_FRAMEWORDS as f64 + 0.5) as i64;
@@ -1370,14 +1422,15 @@ impl Paranoia {
 
         let mut new = CBlock::new();
         new.flags = if self.enable & (PARANOIA_MODE_OVERLAP | PARANOIA_MODE_VERIFY) != 0 {
-            Some(vec![0u8; (totaltoread * CD_FRAMEWORDS) as usize])
+            Some(self.take_flag_buf((totaltoread * CD_FRAMEWORDS) as usize))
         } else {
             None
         };
         self.cache.push_front(new);
         self.recover_cache();
 
-        let mut raw = vec![0u8; (totaltoread * CD_FRAMESIZE_RAW as i64) as usize];
+        let word_count = (totaltoread * CD_FRAMEWORDS) as usize;
+        let mut samples = self.take_sample_buf(word_count);
         let mut sofar = 0i64;
         let mut firstread = -1i64;
         let mut anyflag = false;
@@ -1402,12 +1455,12 @@ impl Paranoia {
                 if firstread < 0 {
                     firstread = adjread;
                 }
-                let start = (sofar * CD_FRAMESIZE_RAW as i64) as usize;
-                let end = start + (secread * CD_FRAMESIZE_RAW as i64) as usize;
-                let end = end.min(raw.len());
+                let start = (sofar * CD_FRAMEWORDS) as usize;
+                let end = start + (secread * CD_FRAMEWORDS) as usize;
+                let end = end.min(samples.len());
                 let result = self
                     .d
-                    .read_audio(Some(&mut raw[start..end]), adjread, secread);
+                    .read_audio_samples(&mut samples[start..end], adjread, secread);
                 let thisread = match result {
                     Ok(n) => {
                         let mut n = n as i64;
@@ -1418,8 +1471,10 @@ impl Paranoia {
                     }
                     Err(e) => {
                         if e.errno == libc::ENOMEDIUM {
-                            self.cache.pop_front();
-                            return None;
+                            if let Some(block) = self.cache.pop_front() {
+                                self.recycle_block(block);
+                            }
+                            return false;
                         }
                         0
                     }
@@ -1428,15 +1483,13 @@ impl Paranoia {
                     if thisread >= 0 {
                         callback((adjread + thisread) * CD_FRAMEWORDS, PARANOIA_CB_READERR);
                     }
-                    let start = (sofar + thisread) as usize * CD_FRAMESIZE_RAW;
-                    let end = (sofar + secread) as usize * CD_FRAMESIZE_RAW;
-                    if start < raw.len() {
-                        let end = end.min(raw.len());
-                        raw[start..end].fill(0);
+                    let start = ((sofar + thisread) * CD_FRAMEWORDS) as usize;
+                    let end = ((sofar + secread) * CD_FRAMEWORDS) as usize;
+                    if start < samples.len() {
+                        let end = end.min(samples.len());
+                        samples[start..end].fill(0);
                     }
                     if let Some(flags) = self.cache.front_mut().and_then(|c| c.flags.as_mut()) {
-                        let start = ((sofar + thisread) * CD_FRAMEWORDS) as usize;
-                        let end = ((sofar + secread) * CD_FRAMEWORDS) as usize;
                         if start < flags.len() {
                             let end = end.min(flags.len());
                             flags[start..end].fill(FLAGS_UNREAD);
@@ -1476,23 +1529,20 @@ impl Paranoia {
 
         if anyflag {
             let words = (sofar * CD_FRAMEWORDS) as usize;
-            let bytes = (sofar * CD_FRAMESIZE_RAW as i64) as usize;
-            raw.truncate(bytes);
-            let samples = crate::device::bytes_to_samples(&raw);
-            let mut flags = self.cache.front().and_then(|c| c.flags.clone());
-            if let Some(f) = flags.as_mut() {
-                f.truncate(words);
+            samples.truncate(words);
+            let block = self.cache.front_mut().unwrap();
+            if let Some(flags) = block.flags.as_mut() {
+                flags.truncate(words);
             }
-            let mut new = self.cache.pop_front().unwrap();
-            new.vector = samples;
-            new.flags = flags;
-            new.begin = firstread * CD_FRAMEWORDS - self.dyndrift;
-            new.size = words as i64;
-            self.cache.push_front(new);
-            Some(self.cache.front().unwrap().clone())
+            block.vector = Arc::new(samples);
+            block.begin = firstread * CD_FRAMEWORDS - self.dyndrift;
+            block.size = words as i64;
+            true
         } else {
-            self.cache.pop_front();
-            None
+            if let Some(block) = self.cache.pop_front() {
+                self.recycle_block(block);
+            }
+            false
         }
     }
 
@@ -1535,9 +1585,9 @@ impl Paranoia {
             let frag_end = new.begin + (end + OVERLAP_ADJ).min(new.size);
             let lastsector = end + OVERLAP_ADJ >= new.size && new.lastsector;
             let start_idx = (frag_begin - new.begin) as usize;
-            let end_idx = (frag_end - new.begin) as usize;
             self.fragments.push(Some(VFragment {
-                vector: new.vector[start_idx..end_idx].to_vec(),
+                data: Arc::clone(&new.vector),
+                offset: start_idx,
                 begin: frag_begin,
                 size: frag_end - frag_begin,
                 lastsector,
@@ -1586,7 +1636,7 @@ impl Paranoia {
                 }
                 if let Some(id) = initialized {
                     let v = self.fragments[id].take().unwrap();
-                    let c = CBlock::from_parts(v.vector, v.begin, v.lastsector);
+                    let c = CBlock::from_parts(v.vector().to_vec(), v.begin, v.lastsector);
                     self.root.lastsector = v.lastsector;
                     self.root.returned_limit = beginword;
                     self.root.silence_flag = false;
@@ -1726,7 +1776,8 @@ impl Paranoia {
                     if v.begin < av {
                         // Drop fragments that would move before absolute zero.
                         *v = VFragment {
-                            vector: Vec::new(),
+                            data: Arc::new(Vec::new()),
+                            offset: 0,
                             begin: 0,
                             size: -1,
                             lastsector: false,
@@ -1754,29 +1805,38 @@ impl Paranoia {
     }
 
     fn trim(&mut self, beginword: i64) {
+        let mut free_root = false;
         if let Some(root) = self.root.vector.as_mut() {
             let target = beginword - MAX_SECTOR_OVERLAP * CD_FRAMEWORDS;
             let rbegin = root.begin;
             let rend = root.end();
             if rbegin > beginword {
-                self.root.vector = None;
-                self.root.returned_limit = -1;
-                self.root.lastsector = false;
-                return;
-            }
-            if rbegin + MAX_SECTOR_OVERLAP * CD_FRAMEWORDS < beginword {
+                free_root = true;
+            } else if rbegin + MAX_SECTOR_OVERLAP * CD_FRAMEWORDS < beginword {
                 if target + MIN_WORDS_OVERLAP > rend {
-                    self.root.vector = None;
-                    self.root.returned_limit = -1;
-                    self.root.lastsector = false;
-                    return;
+                    free_root = true;
+                } else {
+                    let offset = target - rbegin;
+                    root.remove_front(offset);
                 }
-                let offset = target - rbegin;
-                root.remove_front(offset);
             }
         }
+        if free_root {
+            self.recycle_root();
+            self.root.returned_limit = -1;
+            self.root.lastsector = false;
+            return;
+        }
         let cutoff = beginword - MAX_SECTOR_OVERLAP * CD_FRAMEWORDS;
-        self.cache.retain(|c| c.end() >= cutoff);
+        let mut kept = VecDeque::with_capacity(self.cache.len());
+        while let Some(block) = self.cache.pop_front() {
+            if block.end() >= cutoff {
+                kept.push_back(block);
+            } else {
+                self.recycle_block(block);
+            }
+        }
+        self.cache = kept;
     }
 
     fn end_case(&mut self, endword: i64) {
@@ -1856,7 +1916,8 @@ impl Paranoia {
             gend = (gend + OVERLAP_ADJ).min(cend);
             if self.root.is_empty() {
                 let c = &self.cache[idx];
-                self.root.vector = Some(CBlock::from_parts(c.vector.clone(), cbegin, false));
+                self.root.vector =
+                    Some(CBlock::from_parts(c.vector.as_ref().clone(), cbegin, false));
             } else {
                 let c = &self.cache[idx];
                 let data: Vec<i16> =
@@ -1904,7 +1965,8 @@ impl Paranoia {
                 if let Some(root) = self.root.vector.as_mut() {
                     if root.begin > beginword {
                         let add = (root.begin - beginword) as usize;
-                        root.vector.splice(0..0, std::iter::repeat_n(0i16, add));
+                        Arc::make_mut(&mut root.vector)
+                            .splice(0..0, std::iter::repeat_n(0i16, add));
                         root.size += add as i64;
                         root.begin = beginword;
                     }
@@ -1938,63 +2000,63 @@ impl Paranoia {
             let satisfied = !(self.root.begin() == -1
                 || self.root.begin() > beginword
                 || self.root.end() < endword + MAX_SECTOR_OVERLAP * CD_FRAMEWORDS);
-            if std::env::var_os("CDR_NEG").is_some() {
-                eprintln!(
-                    "neg loop cursor={} root={:?}..{:?} need={} satisfied={} retry={}",
-                    self.cursor,
-                    self.root.begin(),
-                    self.root.end(),
-                    need_more,
-                    satisfied,
-                    retry_count
-                );
-            }
             if satisfied {
                 break;
             }
 
-            let new = self.read_c_block(beginword, endword, callback);
-            if std::env::var_os("CDR_NEG").is_some() {
-                eprintln!(
-                    "  new={:?} frags={}",
-                    new.as_ref().map(|b| (b.begin, b.size)),
-                    self.fragments.iter().filter(|f| f.is_some()).count()
-                );
-            }
-            if let Some(mut new) = new {
+            if self.read_c_block(beginword, endword, callback) {
                 if self.enable & (PARANOIA_MODE_OVERLAP | PARANOIA_MODE_VERIFY) != 0 {
                     if self.enable & PARANOIA_MODE_VERIFY != 0 {
-                        // stage1() expects the new block at the head.
+                        // stage1() expects the new block at the head and
+                        // leaves it there when it returns.
                         self.stage1(callback);
                     } else {
-                        let mut begin = 0i64;
-                        while begin < new.size {
-                            while begin < new.size
-                                && new.flags.as_ref().unwrap()[begin as usize] & FLAGS_EDGE != 0
-                            {
-                                begin += 1;
+                        // Build fragments from the block already at the
+                        // cache head.  Collect first so the cache borrow is
+                        // released before touching self.fragments.
+                        let mut new_frags = Vec::new();
+                        {
+                            let new = self.cache.front().unwrap();
+                            if let Some(flags) = new.flags.as_ref() {
+                                let mut begin = 0i64;
+                                while begin < new.size {
+                                    while begin < new.size
+                                        && flags[begin as usize] & FLAGS_EDGE != 0
+                                    {
+                                        begin += 1;
+                                    }
+                                    let mut end = begin + 1;
+                                    while end < new.size && flags[end as usize] & FLAGS_EDGE == 0 {
+                                        end += 1;
+                                    }
+                                    let frag_begin = new.begin + begin;
+                                    let frag_end = new.begin + end;
+                                    let lastsector = new.lastsector && new.begin + end == new.end();
+                                    new_frags.push(VFragment {
+                                        data: Arc::clone(&new.vector),
+                                        offset: begin as usize,
+                                        begin: frag_begin,
+                                        size: frag_end - frag_begin,
+                                        lastsector,
+                                    });
+                                    begin = end;
+                                }
+                            } else {
+                                new_frags.push(VFragment {
+                                    data: Arc::clone(&new.vector),
+                                    offset: 0,
+                                    begin: new.begin,
+                                    size: new.size,
+                                    lastsector: new.lastsector,
+                                });
                             }
-                            let mut end = begin + 1;
-                            while end < new.size
-                                && new.flags.as_ref().unwrap()[end as usize] & FLAGS_EDGE == 0
-                            {
-                                end += 1;
-                            }
-                            let frag_begin = new.begin + begin;
-                            let frag_end = new.begin + end;
-                            let lastsector = new.lastsector && new.begin + end == new.end();
-                            self.fragments.push(Some(VFragment {
-                                vector: new.vector[begin as usize..end as usize].to_vec(),
-                                begin: frag_begin,
-                                size: frag_end - frag_begin,
-                                lastsector,
-                            }));
-                            begin = end;
                         }
+                        self.fragments.extend(new_frags.into_iter().map(Some));
                     }
                 } else {
+                    let new = self.cache.pop_front().unwrap();
                     self.root.vector = Some(CBlock {
-                        vector: std::mem::take(&mut new.vector),
+                        vector: new.vector,
                         flags: None,
                         begin: new.begin,
                         size: new.size,
@@ -2038,6 +2100,7 @@ impl Paranoia {
         if end > root.vector.len() {
             return None;
         }
-        Some(&mut root.vector[start..end])
+        let vector = Arc::make_mut(&mut root.vector);
+        Some(&mut vector[start..end])
     }
 }

crates/core/src/paranoia/sort.rs

@@ -1,87 +1,315 @@
-//! Sample-value index, a safe Rust equivalent of isort.c.
+//! Sample-value index for paranoia.
+//!
+//! This is a Rust equivalent of the original `isort.c`, with two strategies:
+//!
+//! * small search ranges (stage 2) use a direct linear scan, avoiding the
+//!   cost of building an index for a few hundred samples;
+//! * large ranges (stage 1) use a compact CSR-style index with one bucket
+//!   per 16-bit sample value.
+//!
+//! The CSR index has no per-value `Vec` allocations and no hashing, which is
+//! important because stage 1 indexes up to 1200 CD sectors at a time.
 
-use std::collections::HashMap;
+const BUCKETS: usize = 65536;
+const LINEAR_THRESHOLD: usize = 4096;
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+enum Mode {
+    Empty,
+    Linear,
+    Csr,
+}
+
+#[derive(Clone, Copy, Debug)]
+enum Cursor {
+    Linear {
+        value: i16,
+        next: usize,
+        hi: usize,
+        current: usize,
+    },
+    Csr {
+        key: usize,
+        next: usize,
+        hi: usize,
+        current: usize,
+    },
+}
 
 pub struct SortIndex {
-    buckets: HashMap<i16, Vec<u32>>,
+    mode: Mode,
     pub begin: i64,
     pub size: usize,
-    cursor: Option<(i16, usize, usize)>, // value, next bucket index, hi
+    index_lo: usize,
+    index_hi: usize,
+
+    // CSR payload: positions grouped by sample value.
+    positions: Vec<u32>,
+    starts: Vec<u32>,
+    write: Vec<u32>,
+
+    cursor: Option<Cursor>,
 }
 
 impl SortIndex {
     pub fn new(_maxsize: usize) -> Self {
         Self {
-            buckets: HashMap::new(),
+            mode: Mode::Empty,
             begin: 0,
             size: 0,
+            index_lo: 0,
+            index_hi: 0,
+            positions: Vec::new(),
+            starts: Vec::new(),
+            write: Vec::new(),
             cursor: None,
         }
     }
 
     pub fn setup(&mut self, samples: &[i16], begin_abs: i64, sortlo: i64, sorthi: i64) {
-        self.buckets.clear();
         self.begin = begin_abs;
         self.size = samples.len();
         self.cursor = None;
         let lo = ((sortlo - begin_abs).max(0) as usize).min(samples.len());
         let hi = ((sorthi - begin_abs).max(0) as usize).min(samples.len());
+        self.index_lo = lo;
+        self.index_hi = hi;
+
         if lo >= hi {
+            self.mode = Mode::Empty;
             return;
         }
-        for (i, sample) in samples.iter().enumerate().take(hi).skip(lo) {
-            self.buckets.entry(*sample).or_default().push(i as u32);
+
+        if hi - lo <= LINEAR_THRESHOLD {
+            self.mode = Mode::Linear;
+            return;
+        }
+
+        self.mode = Mode::Csr;
+        if self.starts.is_empty() {
+            self.starts = vec![0u32; BUCKETS + 1];
+            self.write = vec![0u32; BUCKETS];
+        } else {
+            self.starts.fill(0);
+        }
+        let range_len = hi - lo;
+        self.positions.resize(range_len, 0);
+
+        for &sample in &samples[lo..hi] {
+            self.starts[(sample as u16) as usize + 1] += 1;
+        }
+        for i in 1..=BUCKETS {
+            self.starts[i] += self.starts[i - 1];
+        }
+        self.write.copy_from_slice(&self.starts[..BUCKETS]);
+
+        for (offset, &sample) in samples[lo..hi].iter().enumerate() {
+            let key = (sample as u16) as usize;
+            let slot = self.write[key] as usize;
+            self.positions[slot] = (lo + offset) as u32;
+            self.write[key] += 1;
         }
     }
 
     /// Equivalent of sort_getmatch(). Returns the first matching relative
     /// position, and leaves a cursor for sort_nextmatch().
-    pub fn getmatch(&mut self, post: i64, overlap: i64, value: i16) -> Option<usize> {
+    pub fn getmatch(
+        &mut self,
+        samples: &[i16],
+        post: i64,
+        overlap: i64,
+        value: i16,
+    ) -> Option<usize> {
+        self.cursor = None;
         let post = post.clamp(0, self.size as i64);
         let lo = (post - overlap).max(0) as usize;
         let hi = ((post + overlap).min(self.size as i64)).max(0) as usize;
-        self.cursor = None;
-        let positions = self.buckets.get(&value)?;
-        let idx = positions.partition_point(|p| (*p as usize) < lo);
-        if idx >= positions.len() {
-            return None;
+
+        match self.mode {
+            Mode::Empty => None,
+            Mode::Linear => {
+                let start = lo.max(self.index_lo);
+                let end = hi.min(self.index_hi);
+                if start >= end {
+                    return None;
+                }
+                if let Some(offset) = samples[start..end]
+                    .iter()
+                    .position(|&sample| sample == value)
+                {
+                    let pos = start + offset;
+                    self.cursor = Some(Cursor::Linear {
+                        value,
+                        next: pos + 1,
+                        hi: end,
+                        current: pos,
+                    });
+                    return Some(pos);
+                }
+                None
+            }
+            Mode::Csr => {
+                let key = (value as u16) as usize;
+                let start = self.starts[key] as usize;
+                let end = self.starts[key + 1] as usize;
+                let idx =
+                    start + self.positions[start..end].partition_point(|p| (*p as usize) < lo);
+                if idx >= end {
+                    return None;
+                }
+                let pos = self.positions[idx] as usize;
+                if pos >= hi {
+                    return None;
+                }
+                self.cursor = Some(Cursor::Csr {
+                    key,
+                    next: idx + 1,
+                    hi,
+                    current: pos,
+                });
+                Some(pos)
+            }
         }
-        let pos = positions[idx] as usize;
-        if pos >= hi {
-            return None;
-        }
-        self.cursor = Some((value, idx + 1, hi));
-        Some(pos)
     }
 
-    pub fn nextmatch(&mut self) -> Option<usize> {
-        let (value, idx, hi) = self.cursor?;
-        let positions = self.buckets.get(&value)?;
-        if idx >= positions.len() {
-            self.cursor = None;
-            return None;
+    pub fn nextmatch(&mut self, samples: &[i16]) -> Option<usize> {
+        match self.cursor.take()? {
+            Cursor::Linear {
+                value, next, hi, ..
+            } => {
+                if next >= hi {
+                    return None;
+                }
+                if let Some(offset) = samples[next..hi].iter().position(|&sample| sample == value) {
+                    let pos = next + offset;
+                    self.cursor = Some(Cursor::Linear {
+                        value,
+                        next: pos + 1,
+                        hi,
+                        current: pos,
+                    });
+                    return Some(pos);
+                }
+                None
+            }
+            Cursor::Csr { key, next, hi, .. } => {
+                let end = self.starts[key + 1] as usize;
+                if next >= end {
+                    return None;
+                }
+                let pos = self.positions[next] as usize;
+                if pos >= hi {
+                    return None;
+                }
+                self.cursor = Some(Cursor::Csr {
+                    key,
+                    next: next + 1,
+                    hi,
+                    current: pos,
+                });
+                Some(pos)
+            }
         }
-        let pos = positions[idx] as usize;
-        if pos >= hi {
-            self.cursor = None;
-            return None;
-        }
-        self.cursor = Some((value, idx + 1, hi));
-        Some(pos)
     }
 
     /// Position most recently returned by getmatch()/advance().
     pub fn cursor_position(&self) -> Option<i64> {
-        let (value, idx, _hi) = self.cursor?;
-        let positions = self.buckets.get(&value)?;
-        if idx == 0 || idx > positions.len() {
-            return None;
+        match self.cursor? {
+            Cursor::Linear { current, .. } | Cursor::Csr { current, .. } => Some(current as i64),
         }
-        Some(positions[idx - 1] as i64)
     }
 
     /// Advance to the next match. Returns false when exhausted.
-    pub fn advance(&mut self) -> bool {
-        self.nextmatch().is_some()
+    pub fn advance(&mut self, samples: &[i16]) -> bool {
+        self.nextmatch(samples).is_some()
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn naive_matches(
+        samples: &[i16],
+        index_lo: usize,
+        index_hi: usize,
+        post: i64,
+        overlap: i64,
+        value: i16,
+    ) -> Vec<usize> {
+        let post = post.clamp(0, samples.len() as i64);
+        let lo = (post - overlap).max(0) as usize;
+        let hi = ((post + overlap).min(samples.len() as i64)).max(0) as usize;
+        (lo.max(index_lo)..hi.min(index_hi))
+            .filter(|&i| samples[i] == value)
+            .collect()
+    }
+
+    fn collect_matches(
+        index: &mut SortIndex,
+        samples: &[i16],
+        post: i64,
+        overlap: i64,
+        value: i16,
+    ) -> Vec<usize> {
+        let mut out = Vec::new();
+        if let Some(first) = index.getmatch(samples, post, overlap, value) {
+            out.push(first);
+            while let Some(next) = index.nextmatch(samples) {
+                out.push(next);
+            }
+        }
+        out
+    }
+
+    #[test]
+    fn adaptive_index_matches_naive_search() {
+        let mut x = 0x1234_5678u64;
+        let mut samples = Vec::with_capacity(12000);
+        for i in 0..12000 {
+            x ^= x << 13;
+            x ^= x >> 7;
+            x ^= x << 17;
+            let value = if i % 7 == 0 {
+                0
+            } else {
+                ((x as i32) % 9 - 4) as i16
+            };
+            samples.push(value);
+        }
+
+        let mut index = SortIndex::new(samples.len());
+        for (lo, hi) in [(0usize, samples.len()), (300, 900), (1000, 1400)] {
+            index.setup(&samples, 0, lo as i64, hi as i64);
+            let expected_mode = if hi - lo <= LINEAR_THRESHOLD {
+                Mode::Linear
+            } else {
+                Mode::Csr
+            };
+            assert_eq!(index.mode, expected_mode);
+            for post in [0i64, 1, 500, 1500, 9000, 11999] {
+                for overlap in [0i64, 1, 64, 512] {
+                    for value in -4i16..=4 {
+                        let expected = naive_matches(&samples, lo, hi, post, overlap, value);
+                        let got = collect_matches(&mut index, &samples, post, overlap, value);
+                        assert_eq!(
+                            got, expected,
+                            "lo={lo} hi={hi} post={post} overlap={overlap} value={value}"
+                        );
+                    }
+                }
+            }
+        }
+    }
+
+    #[test]
+    fn duplicate_bucket_is_ordered() {
+        let samples = vec![0i16; 20000];
+        let mut index = SortIndex::new(samples.len());
+        index.setup(&samples, 0, 0, samples.len() as i64);
+        assert_eq!(index.mode, Mode::Csr);
+        let got = collect_matches(&mut index, &samples, 10000, 200, 0);
+        let expected = (9800..10200).collect::<Vec<_>>();
+        assert_eq!(got, expected);
     }
 }