Stream large files during unpacking

src/cli/self_update.rs

@@ -413,6 +413,7 @@ pub fn install(
 
 fn rustc_or_cargo_exists_in_path() -> Result<()> {
     // Ignore rustc and cargo if present in $HOME/.cargo/bin or a few other directories
+    #[allow(clippy::ptr_arg)]
     fn ignore_paths(path: &PathBuf) -> bool {
         !path
             .components()

src/cli/self_update/windows.rs

@@ -180,6 +180,7 @@ fn _apply_new_path(new_path: Option<Vec<u16>>) -> Result<()> {
     }
 
     // Tell other processes to update their environment
+    #[allow(clippy::unnecessary_cast)]
     unsafe {
         SendMessageTimeoutA(
             HWND_BROADCAST,

src/cli/topical_doc.rs

@@ -22,7 +22,7 @@ fn index_html(doc: &DocData<'_>, wpath: &Path) -> Option<PathBuf> {
     }
 }
 
-fn dir_into_vec(dir: &PathBuf) -> Result<Vec<OsString>> {
+fn dir_into_vec(dir: &Path) -> Result<Vec<OsString>> {
     let entries = fs::read_dir(dir).chain_err(|| format!("Opening directory {:?}", dir))?;
     let mut v = Vec::new();
     for entry in entries {

src/config.rs

@@ -110,12 +110,12 @@ impl<'a> OverrideCfg<'a> {
                         || file.toolchain.components.is_some()
                         || file.toolchain.profile.is_some()
                     {
-                        return Err(ErrorKind::CannotSpecifyPathAndOptions(path.into()).into());
+                        return Err(ErrorKind::CannotSpecifyPathAndOptions(path).into());
                     }
                     Some(Toolchain::from_path(cfg, cfg_path, &path)?)
                 }
                 (Some(channel), Some(path)) => {
-                    return Err(ErrorKind::CannotSpecifyChannelAndPath(channel, path.into()).into())
+                    return Err(ErrorKind::CannotSpecifyChannelAndPath(channel, path).into())
                 }
                 (None, None) => None,
             },
@@ -172,8 +172,7 @@ impl PgpPublicKey {
             Ok(ret)
         }
         use pgp::types::KeyTrait;
-        let mut ret = Vec::new();
-        ret.push(format!("from {}", self));
+        let mut ret = vec![format!("from {}", self)];
         let key = self.key();
         let keyid = format_hex(&key.key_id().to_vec(), "-", 4)?;
         let algo = key.algorithm();

src/diskio/immediate.rs

@@ -2,27 +2,204 @@
 ///
 /// Use for diagnosing bugs or working around any unexpected issues with the
 /// threaded code paths.
-use super::{perform, Executor, Item};
+use std::{
+    fmt::Debug,
+    fs::{File, OpenOptions},
+    io::{self, Write},
+    path::Path,
+    sync::{Arc, Mutex},
+    time::Instant,
+};
+
+use super::{CompletedIo, Executor, Item};
+
+#[derive(Debug)]
+pub struct _IncrementalFileState {
+    completed_chunks: Vec<usize>,
+    err: Option<io::Result<()>>,
+    item: Option<Item>,
+    finished: bool,
+}
+
+pub(super) type IncrementalFileState = Arc<Mutex<Option<_IncrementalFileState>>>;
+
+#[derive(Default, Debug)]
+pub struct ImmediateUnpacker {
+    incremental_state: IncrementalFileState,
+}
 
-#[derive(Default)]
-pub struct ImmediateUnpacker {}
 impl ImmediateUnpacker {
     pub fn new() -> Self {
-        Self {}
+        Self {
+            ..Default::default()
+        }
+    }
+
+    fn deque(&self) -> Box<dyn Iterator<Item = CompletedIo>> {
+        let mut guard = self.incremental_state.lock().unwrap();
+        // incremental file in progress
+        if let Some(ref mut state) = *guard {
+            // Case 1: pending errors
+            if state.finished {
+                let mut item = state.item.take().unwrap();
+                if state.err.is_some() {
+                    let err = state.err.take().unwrap();
+                    item.result = err;
+                }
+                item.finish = item
+                    .start
+                    .map(|s| Instant::now().saturating_duration_since(s));
+                if state.finished {
+                    *guard = None;
+                }
+                Box::new(Some(CompletedIo::Item(item)).into_iter())
+            } else {
+                // Case 2: pending chunks (which might be empty)
+                let mut completed_chunks = vec![];
+                completed_chunks.append(&mut state.completed_chunks);
+                Box::new(completed_chunks.into_iter().map(CompletedIo::Chunk))
+            }
+        } else {
+            Box::new(None.into_iter())
+        }
     }
 }
 
 impl Executor for ImmediateUnpacker {
-    fn dispatch(&self, mut item: Item) -> Box<dyn Iterator<Item = Item> + '_> {
-        perform(&mut item);
-        Box::new(Some(item).into_iter())
+    fn dispatch(&self, mut item: Item) -> Box<dyn Iterator<Item = CompletedIo> + '_> {
+        item.result = match &mut item.kind {
+            super::Kind::Directory => super::create_dir(&item.full_path),
+            super::Kind::File(ref contents) => {
+                super::write_file(&item.full_path, &contents, item.mode)
+            }
+            super::Kind::IncrementalFile(_incremental_file) => {
+                return {
+                    // If there is a pending error, return it, otherwise stash the
+                    // Item for eventual return when the file is finished.
+                    let mut guard = self.incremental_state.lock().unwrap();
+                    if let Some(ref mut state) = *guard {
+                        if state.err.is_some() {
+                            let err = state.err.take().unwrap();
+                            item.result = err;
+                            item.finish = item
+                                .start
+                                .map(|s| Instant::now().saturating_duration_since(s));
+                            *guard = None;
+                            Box::new(Some(CompletedIo::Item(item)).into_iter())
+                        } else {
+                            state.item = Some(item);
+                            Box::new(None.into_iter())
+                        }
+                    } else {
+                        unreachable!();
+                    }
+                };
+            }
+        };
+        item.finish = item
+            .start
+            .map(|s| Instant::now().saturating_duration_since(s));
+        Box::new(Some(CompletedIo::Item(item)).into_iter())
+    }
+
+    fn join(&mut self) -> Box<dyn Iterator<Item = CompletedIo>> {
+        self.deque()
     }
 
-    fn join(&mut self) -> Box<dyn Iterator<Item = Item>> {
-        Box::new(None.into_iter())
+    fn completed(&self) -> Box<dyn Iterator<Item = CompletedIo>> {
+        self.deque()
     }
 
-    fn completed(&self) -> Box<dyn Iterator<Item = Item>> {
-        Box::new(None.into_iter())
+    fn incremental_file_state(&self) -> super::IncrementalFileState {
+        let mut state = self.incremental_state.lock().unwrap();
+        if state.is_some() {
+            unreachable!();
+        } else {
+            *state = Some(_IncrementalFileState {
+                completed_chunks: vec![],
+                err: None,
+                item: None,
+                finished: false,
+            });
+            super::IncrementalFileState::Immediate(self.incremental_state.clone())
+        }
+    }
+}
+
+/// The non-shared state for writing a file incrementally
+#[derive(Debug)]
+pub(super) struct IncrementalFileWriter {
+    state: IncrementalFileState,
+    file: Option<File>,
+    path_display: String,
+}
+
+impl IncrementalFileWriter {
+    #[allow(unused_variables)]
+    pub fn new<P: AsRef<Path>>(
+        path: P,
+        mode: u32,
+        state: IncrementalFileState,
+    ) -> std::result::Result<Self, io::Error> {
+        let mut opts = OpenOptions::new();
+        #[cfg(unix)]
+        {
+            use std::os::unix::fs::OpenOptionsExt;
+            opts.mode(mode);
+        }
+        let path = path.as_ref();
+        let path_display = format!("{}", path.display());
+        let file = Some({
+            trace_scoped!("creat", "name": path_display);
+            opts.write(true).create(true).truncate(true).open(path)?
+        });
+        Ok(IncrementalFileWriter {
+            file,
+            state,
+            path_display,
+        })
+    }
+
+    pub fn chunk_submit(&mut self, chunk: Vec<u8>) -> bool {
+        if (self.state.lock().unwrap()).is_none() {
+            return false;
+        }
+        match self.write(chunk) {
+            Ok(v) => v,
+            Err(e) => {
+                let mut state = self.state.lock().unwrap();
+                if let Some(ref mut state) = *state {
+                    state.err.replace(Err(e));
+                    state.finished = true;
+                    false
+                } else {
+                    false
+                }
+            }
+        }
+    }
+
+    fn write(&mut self, chunk: Vec<u8>) -> std::result::Result<bool, io::Error> {
+        let mut state = self.state.lock().unwrap();
+        if let Some(ref mut state) = *state {
+            if let Some(ref mut file) = (&mut self.file).as_mut() {
+                // Length 0 vector is used for clean EOF signalling.
+                if chunk.is_empty() {
+                    trace_scoped!("close", "name:": self.path_display);
+                    drop(std::mem::take(&mut self.file));
+                    state.finished = true;
+                } else {
+                    trace_scoped!("write_segment", "name": self.path_display, "len": chunk.len());
+                    file.write_all(&chunk)?;
+
+                    state.completed_chunks.push(chunk.len());
+                }
+                Ok(true)
+            } else {
+                Ok(false)
+            }
+        } else {
+            unreachable!();
+        }
     }
 }