Make obvious that interrupt request was received

git-features/src/interruptible.rs

@@ -5,16 +5,33 @@ use std::{
 
 #[cfg(feature = "interrupt-handler")]
 mod _impl {
-    pub fn init_interrupt_handler() {
-        ctrlc::set_handler(|| {
-            super::IS_INTERRUPTED.store(true, std::sync::atomic::Ordering::Relaxed);
+    use std::{
+        io,
+        sync::atomic::{AtomicUsize, Ordering},
+    };
+
+    pub fn init_interrupt_handler(mut message_channel: impl io::Write + Send + 'static) {
+        ctrlc::set_handler(move || {
+            const MESSAGES: &[&'static str] = &[
+                "interrupt requested", 
+                "please wait…", 
+                "the program will respond soon…", 
+                "if the program doesn't respond quickly enough, please let us know here: https://github.com/Byron/gitoxide/issues"
+            ];
+            static CURRENT_MESSAGE: AtomicUsize = AtomicUsize::new(0);
+            if !super::is_interrupted() {
+                CURRENT_MESSAGE.store(0, Ordering::Relaxed);
+            }
+            let msg_idx =CURRENT_MESSAGE.fetch_add(1, Ordering::Relaxed);
+            super::IS_INTERRUPTED.store(true, Ordering::Relaxed);
+            writeln!(message_channel, "{}", MESSAGES[msg_idx % MESSAGES.len()]).ok();
         })
         .expect("it is up to the application to ensure only one interrupt handler is installed, and this function is called only once.")
     }
 }
 #[cfg(not(feature = "interrupt-handler"))]
 mod _impl {
-    pub fn init_interrupt_handler() {}
+    pub fn init_interrupt_handler(mut message_channel: impl io::Write + Send + 'static) {}
 }
 pub use _impl::init_interrupt_handler;
 

git-odb/src/pack/tree/from_offsets.rs

@@ -1,5 +1,8 @@
 use crate::{pack, pack::index::access::PackOffset, pack::tree::Tree};
-use git_features::progress::{self, Progress};
+use git_features::{
+    interruptible::is_interrupted,
+    progress::{self, Progress},
+};
 use quick_error::quick_error;
 use std::{
     fs, io,
@@ -26,6 +29,9 @@ quick_error! {
             source(err)
             from()
         }
+        Interrupted {
+            display("Interrupted by user")
+        }
     }
 }
 
@@ -70,7 +76,7 @@ impl<T> Tree<T> {
 
         let mut previous_cursor_position = None::<u64>;
 
-        for data in data_sorted_by_offsets {
+        for (idx, data) in data_sorted_by_offsets.enumerate() {
             let pack_offset = get_pack_offset(&data);
             if let Some(previous_offset) = previous_cursor_position {
                 Self::advance_cursor_to_pack_offset(&mut r, pack_offset, previous_offset)?;
@@ -99,6 +105,9 @@ impl<T> Tree<T> {
                 }
             };
             progress.inc();
+            if idx % 10_000 == 0 && is_interrupted() {
+                return Err(Error::Interrupted);
+            }
         }
 
         progress.show_throughput(then);

src/plumbing/lean.rs

@@ -173,7 +173,7 @@ fn prepare(
 pub fn main() -> Result<()> {
     pub use options::*;
     let cli: Args = crate::shared::from_env();
-    git_features::interruptible::init_interrupt_handler();
+    git_features::interruptible::init_interrupt_handler(std::io::stderr());
     let thread_limit = cli.threads;
     let verbose = cli.verbose;
     match cli.subcommand {

src/plumbing/pretty.rs

@@ -277,7 +277,7 @@ pub fn main() -> Result<()> {
         format,
         cmd,
     } = Args::parse();
-    git_features::interruptible::init_interrupt_handler();
+    git_features::interruptible::init_interrupt_handler(std::io::stderr());
 
     match cmd {
         Subcommands::IndexFromPack {

src/porcelain/lean.rs

@@ -30,7 +30,7 @@ use gitoxide_core as core;
 pub fn main() -> Result<()> {
     pub use options::*;
     let cli: Args = crate::shared::from_env();
-    git_features::interruptible::init_interrupt_handler();
+    git_features::interruptible::init_interrupt_handler(std::io::stderr());
 
     match cli.subcommand {
         SubCommands::Init(_) => core::repository::init(),

src/porcelain/pretty.rs

@@ -27,7 +27,7 @@ mod options {
 pub fn main() -> Result<()> {
     use options::*;
     let args = Args::parse();
-    git_features::interruptible::init_interrupt_handler();
+    git_features::interruptible::init_interrupt_handler(std::io::stderr());
     match args.cmd {
         Subcommands::Init => core::repository::init(),
     }?;