From a940f525a8aa92a87c3f4159510d73f1baa2e0b2 Mon Sep 17 00:00:00 2001
From: Sebastien Boeuf <sebastien.boeuf@intel.com>
Date: Thu, 25 Aug 2022 10:26:59 +0200
Subject: [PATCH] vmm: Move SerialBuffer to its own crate

We want to be able to reuse the SerialBuffer from the virtio-devices
crate, particularly from the virtio-console implementation. That's why
we move the SerialBuffer definition to its own crate so that it can be
accessed from both vmm and virtio-devices crates, without creating any
cyclic dependency.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
---
 Cargo.lock                                           | 6 ++++++
 Cargo.toml                                           | 1 +
 serial_buffer/Cargo.toml                             | 5 +++++
 vmm/src/serial_buffer.rs => serial_buffer/src/lib.rs | 4 ++--
 vmm/Cargo.toml                                       | 1 +
 vmm/src/lib.rs                                       | 1 -
 vmm/src/serial_manager.rs                            | 2 +-
 7 files changed, 16 insertions(+), 4 deletions(-)
 create mode 100644 serial_buffer/Cargo.toml
 rename vmm/src/serial_buffer.rs => serial_buffer/src/lib.rs (96%)

diff --git a/Cargo.lock b/Cargo.lock
index 8ce8491de..b3f199fc0 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1011,6 +1011,10 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "serial_buffer"
+version = "0.1.0"
+
 [[package]]
 name = "signal-hook"
 version = "0.3.14"
@@ -1344,6 +1348,7 @@ dependencies = [
  "seccompiler",
  "serde",
  "serde_json",
+ "serial_buffer",
  "thiserror",
  "versionize",
  "versionize_derive",
@@ -1459,6 +1464,7 @@ dependencies = [
  "seccompiler",
  "serde",
  "serde_json",
+ "serial_buffer",
  "signal-hook",
  "thiserror",
  "uuid",
diff --git a/Cargo.toml b/Cargo.toml
index c4fede0cd..948f09dae 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -79,6 +79,7 @@ members = [
     "performance-metrics",
     "qcow",
     "rate_limiter",
+    "serial_buffer",
     "test_infra",
     "vfio_user",
     "vhdx",
diff --git a/serial_buffer/Cargo.toml b/serial_buffer/Cargo.toml
new file mode 100644
index 000000000..f5329eb2d
--- /dev/null
+++ b/serial_buffer/Cargo.toml
@@ -0,0 +1,5 @@
+[package]
+name = "serial_buffer"
+version = "0.1.0"
+authors = ["The Cloud Hypervisor Authors"]
+edition = "2021"
\ No newline at end of file
diff --git a/vmm/src/serial_buffer.rs b/serial_buffer/src/lib.rs
similarity index 96%
rename from vmm/src/serial_buffer.rs
rename to serial_buffer/src/lib.rs
index fbf7cb753..f01f31aa7 100644
--- a/vmm/src/serial_buffer.rs
+++ b/serial_buffer/src/lib.rs
@@ -16,14 +16,14 @@ const MAX_BUFFER_SIZE: usize = 1 << 20;
 
 // Circular buffer implementation for serial output.
 // Read from head; push to tail
-pub(crate) struct SerialBuffer {
+pub struct SerialBuffer {
     buffer: VecDeque<u8>,
     out: Box<dyn Write + Send>,
     write_out: Arc<AtomicBool>,
 }
 
 impl SerialBuffer {
-    pub(crate) fn new(out: Box<dyn Write + Send>, write_out: Arc<AtomicBool>) -> Self {
+    pub fn new(out: Box<dyn Write + Send>, write_out: Arc<AtomicBool>) -> Self {
         Self {
             buffer: VecDeque::new(),
             out,
diff --git a/vmm/Cargo.toml b/vmm/Cargo.toml
index 068e70da7..f37534dd9 100644
--- a/vmm/Cargo.toml
+++ b/vmm/Cargo.toml
@@ -41,6 +41,7 @@ qcow = { path = "../qcow" }
 seccompiler = "0.2.0"
 serde = { version = "1.0.144", features = ["rc", "derive"] }
 serde_json = "1.0.85"
+serial_buffer = { path = "../serial_buffer" }
 signal-hook = "0.3.14"
 thiserror = "1.0.32"
 uuid = "1.1.2"
diff --git a/vmm/src/lib.rs b/vmm/src/lib.rs
index 02285dfc6..9656f3bfc 100644
--- a/vmm/src/lib.rs
+++ b/vmm/src/lib.rs
@@ -70,7 +70,6 @@ pub mod memory_manager;
 pub mod migration;
 mod pci_segment;
 pub mod seccomp_filters;
-mod serial_buffer;
 mod serial_manager;
 mod sigwinch_listener;
 pub mod vm;
diff --git a/vmm/src/serial_manager.rs b/vmm/src/serial_manager.rs
index d694c2eab..d5be4c725 100644
--- a/vmm/src/serial_manager.rs
+++ b/vmm/src/serial_manager.rs
@@ -5,12 +5,12 @@
 
 use crate::config::ConsoleOutputMode;
 use crate::device_manager::PtyPair;
-use crate::serial_buffer::SerialBuffer;
 #[cfg(target_arch = "aarch64")]
 use devices::legacy::Pl011;
 #[cfg(target_arch = "x86_64")]
 use devices::legacy::Serial;
 use libc::EFD_NONBLOCK;
+use serial_buffer::SerialBuffer;
 use std::fs::File;
 use std::io::Read;
 use std::os::unix::io::{AsRawFd, FromRawFd};