From e2ee6784a92d84fa6418b7becdd9f0f75e35e6cb Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?R=C3=BCdiger=20Klaehn?= <rklaehn@protonmail.com>
Date: Thu, 5 Oct 2023 22:57:41 +0300
Subject: [PATCH] feat(iroh): use reflink if possible (#1581)

reflink-copy is a clone of the abandoned reflink crate. Last time there
were some failures on android, so let's see if it works now...

## Description

<!-- A summary of what this pull request achieves and a rough list of
changes. -->

## Notes & open questions

<!-- Any notes, remarks or open questions you have to make about the PR.
-->

## Change checklist

- [ ] Self-review.
- [ ] Documentation updates if relevant.
- [ ] Tests if relevant.
---
 Cargo.lock              | 18 ++++++++++++++++++
 iroh/Cargo.toml         |  3 ++-
 iroh/src/baomap/flat.rs | 12 ++++++++++--
 3 files changed, 30 insertions(+), 3 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index c4a965067b..cd26159303 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1909,6 +1909,12 @@ dependencies = [
  "cfg-if",
 ]
 
+[[package]]
+name = "ioctl-sys"
+version = "0.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8bd11f3a29434026f5ff98c730b668ba74b1033637b8817940b54d040696133c"
+
 [[package]]
 name = "ipconfig"
 version = "0.3.2"
@@ -1970,6 +1976,7 @@ dependencies = [
  "quinn",
  "rand",
  "range-collections",
+ "reflink-copy",
  "regex",
  "rustyline",
  "serde",
@@ -3587,6 +3594,17 @@ dependencies = [
  "syn 2.0.37",
 ]
 
+[[package]]
+name = "reflink-copy"
+version = "0.1.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f9e3947399fd46f412918bafde71ec68f9b3505f11ef082eeb80bc7fdf4d7caf"
+dependencies = [
+ "cfg-if",
+ "ioctl-sys",
+ "windows 0.51.1",
+]
+
 [[package]]
 name = "regex"
 version = "1.9.5"
diff --git a/iroh/Cargo.toml b/iroh/Cargo.toml
index dcad064451..11130733b9 100644
--- a/iroh/Cargo.toml
+++ b/iroh/Cargo.toml
@@ -67,13 +67,14 @@ colored = { version = "2.0.4", optional = true }
 
 # Examples
 ed25519-dalek = { version = "2.0.0", features = ["serde", "rand_core"], optional = true }
+reflink-copy = { version = "0.1.8", optional = true }
 
 [features]
 default = ["cli", "metrics"]
 cli = ["clap", "config", "console", "dirs-next", "indicatif", "multibase", "quic-rpc/quinn-transport", "tokio/rt-multi-thread", "tracing-subscriber", "flat-db", "mem-db", "iroh-collection", "shell-words", "shellexpand", "rustyline", "colored", "toml", "human-time", "comfy-table"]
 metrics = ["iroh-metrics"]
 mem-db = []
-flat-db = []
+flat-db = ["reflink-copy"]
 iroh-collection = []
 test = []
 example-sync = ["cli"]
diff --git a/iroh/src/baomap/flat.rs b/iroh/src/baomap/flat.rs
index 184a80b429..ebf36116f4 100644
--- a/iroh/src/baomap/flat.rs
+++ b/iroh/src/baomap/flat.rs
@@ -883,7 +883,11 @@ impl Store {
                 let temp_path = self.temp_path();
                 // copy the data, since it is not stable
                 progress.try_send(ImportProgress::CopyProgress { id, offset: 0 })?;
-                std::fs::copy(&path, &temp_path)?;
+                if reflink_copy::reflink_or_copy(&path, &temp_path)?.is_none() {
+                    tracing::debug!("reflinked {} to {}", path.display(), temp_path.display());
+                } else {
+                    tracing::debug!("copied {} to {}", path.display(), temp_path.display());
+                }
                 ImportFile::TempFile(temp_path)
             }
         };
@@ -1165,7 +1169,11 @@ impl Store {
             tracing::debug!("copying {} to {}", source.display(), target.display());
             progress(0)?;
             // todo: progress
-            std::fs::copy(&source, &target)?;
+            if reflink_copy::reflink_or_copy(&source, &target)?.is_none() {
+                tracing::debug!("reflinked {} to {}", source.display(), target.display());
+            } else {
+                tracing::debug!("copied {} to {}", source.display(), target.display());
+            }
             progress(size)?;
             let mut state = self.0.state.write().unwrap();
             let Some(entry) = state.complete.get_mut(&hash) else {