build: decouple Cargo.toml: split crate and workspace definitions

TL;DR: cargo clippy|check|... now runs on whole workspace by default.

## Steps

- add new workspace member `cloud-hypervisor`
- move `./src` to new workspace member
- move `./tests` to new workspace member
- move relevant parts from Cargo.toml to new workspace member
- kept necessary parts in main Cargo.toml, such as profile
  configurations

## About

The main Cargo.toml historically mixes workspace and crate definitions
for cloud-hypervisor and ch-remote. This makes it hard to read and
requires `--workspace` to run cargo clippy or cargo test on all
workspace members, which is counter-intuitive.

This patch separates the workspace from the crate definition in the main
Cargo.toml file. After this, cargo clippy, cargo test, etc., work on the
whole workspace naturally, giving a smoother developer experience. The
Cargo.toml without a package definition is also called a virtual
workspace or virtual manifest by Cargo [0].

Backporting is not a concern: CHV no longer backports, but the affected
files are rarely modified anyway.

[0] https://doc.rust-lang.org/cargo/reference/workspaces.html#virtual-workspace

Signed-off-by: Philipp Schuster <philipp.schuster@cyberus-technology.de>
On-behalf-of: SAP philipp.schuster@sap.com

cloud-hypervisor/Cargo.toml

@@ -0,0 +1,69 @@
+[package]
+authors = ["The Cloud Hypervisor Authors"]
+build = "build.rs"
+default-run = "cloud-hypervisor"
+description = "Open source Virtual Machine Monitor (VMM) that runs on top of KVM & MSHV"
+edition = "2024"
+homepage = "https://github.com/cloud-hypervisor/cloud-hypervisor"
+license = "Apache-2.0 AND BSD-3-Clause"
+name = "cloud-hypervisor"
+version = "49.0.0"
+# Minimum buildable version:
+# Keep in sync with version in .github/workflows/build.yaml
+# Policy on MSRV (see #4318):
+# Can only be bumped if satisfying any of the following:
+# a.) A dependency requires it,
+# b.) If we want to use a new feature and that MSRV is at least 6 months old,
+# c.) There is a security issue that is addressed by the toolchain update.
+rust-version = "1.89.0"
+
+[dependencies]
+anyhow = { workspace = true }
+api_client = { path = "../api_client" }
+clap = { workspace = true, features = ["string"] }
+dhat = { workspace = true, optional = true }
+env_logger = { workspace = true }
+epoll = { workspace = true }
+event_monitor = { path = "../event_monitor" }
+hypervisor = { path = "../hypervisor" }
+libc = { workspace = true }
+log = { workspace = true, features = ["std"] }
+option_parser = { path = "../option_parser" }
+seccompiler = { workspace = true }
+serde_json = { workspace = true }
+signal-hook = { workspace = true }
+thiserror = { workspace = true }
+tpm = { path = "../tpm" }
+tracer = { path = "../tracer" }
+vm-memory = { workspace = true }
+vmm = { path = "../vmm" }
+vmm-sys-util = { workspace = true }
+zbus = { version = "5.7.1", optional = true }
+
+[dev-dependencies]
+dirs = { workspace = true }
+net_util = { path = "../net_util" }
+serde_json = { workspace = true }
+test_infra = { path = "../test_infra" }
+wait-timeout = { workspace = true }
+
+# Please adjust `vmm::feature_list()` accordingly when changing the
+# feature list below
+[features]
+dbus_api = ["vmm/dbus_api", "zbus"]
+default = ["io_uring", "kvm"]
+dhat-heap = ["dhat", "vmm/dhat-heap"]       # For heap profiling
+fw_cfg = ["vmm/fw_cfg"]
+guest_debug = ["vmm/guest_debug"]
+igvm = ["mshv", "vmm/igvm"]
+io_uring = ["vmm/io_uring"]
+ivshmem = ["vmm/ivshmem"]
+kvm = ["vmm/kvm"]
+mshv = ["vmm/mshv"]
+pvmemcontrol = ["vmm/pvmemcontrol"]
+sev_snp = ["igvm", "mshv", "vmm/sev_snp"]
+tdx = ["vmm/tdx"]
+tracing = ["tracer/tracing", "vmm/tracing"]
+
+[lints]
+workspace = true

cloud-hypervisor/build.rs

@@ -0,0 +1,32 @@
+// Copyright © 2020 Intel Corporation
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+use std::env;
+use std::process::Command;
+
+fn main() {
+    let mut version = "v".to_owned() + env!("CARGO_PKG_VERSION");
+
+    if let Ok(git_out) = Command::new("git").args(["describe", "--dirty"]).output()
+        && git_out.status.success()
+        && let Ok(git_out_str) = String::from_utf8(git_out.stdout)
+    {
+        version = git_out_str;
+        // Pop the trailing newline.
+        version.pop();
+    }
+
+    // Append CH_EXTRA_VERSION to version if it is set.
+    if let Ok(extra_version) = env::var("CH_EXTRA_VERSION") {
+        println!("cargo:rerun-if-env-changed=CH_EXTRA_VERSION");
+        version.push_str(&format!("-{extra_version}"));
+    }
+
+    // This println!() has a special behavior, as it will set the environment
+    // variable BUILD_VERSION, so that it can be reused from the binary.
+    // Particularly, this is used from src/main.rs to display the exact
+    // version.
+    println!("cargo:rustc-env=BUILD_VERSION={version}");
+}

cloud-hypervisor/src/lib.rs

@@ -0,0 +1,46 @@
+// Copyright © 2025 Cyberus Technology GmbH
+//
+// SPDX-License-Identifier: Apache-2.0
+
+use std::error::Error;
+
+use log::error;
+
+/// Prints a chain of errors to the user in a consistent manner.
+/// The user will see a clear chain of errors, followed by debug output
+/// for opening issues.
+pub fn cli_print_error_chain<'a>(
+    top_error: &'a (dyn Error + 'static),
+    component: &str,
+    // Function optionally returning the display representation of an error.
+    display_modifier: impl Fn(
+        /* level */ usize,
+        /*indention */ usize,
+        &'a (dyn Error + 'static),
+    ) -> Option<String>,
+) {
+    // Debug info.
+    error!("Fatal error: {top_error:?}");
+
+    eprint!("Error: {component} exited with the following ");
+    if top_error.source().is_none() {
+        eprintln!("error:");
+        eprintln!("  {top_error}");
+    } else {
+        eprintln!("chain of errors:");
+        std::iter::successors(Some(top_error), |sub_error| {
+            // Dereference necessary to mitigate rustc compiler bug.
+            // See <https://github.com/rust-lang/rust/issues/141673>
+            (*sub_error).source()
+        })
+        .enumerate()
+        .for_each(|(level, error)| {
+            // Special case: handling of HTTP Server responses in ch-remote
+            if let Some(message) = display_modifier(level, 2, error) {
+                eprintln!("{message}");
+            } else {
+                eprintln!("  {level}: {error}");
+            }
+        });
+    }
+}

cloud-hypervisor/src/test_util.rs

@@ -0,0 +1,24 @@
+// Copyright © 2025 Cyberus Technology GmbH
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+//! Test utilities.
+
+use std::cmp::Ordering;
+
+use clap::Arg;
+
+/// Ensures that all [`Arg`]s are sorted alphabetically.
+pub fn assert_args_sorted<'a, F: Fn() -> R, R: Iterator<Item = &'a Arg>>(get_base_iter: F) {
+    let iter = get_base_iter().zip(get_base_iter().skip(1));
+    for (arg, next) in iter {
+        assert_ne!(
+            arg.get_id().cmp(next.get_id()),
+            Ordering::Greater,
+            "args not alphabetically sorted: arg={}, next={}",
+            arg.get_id(),
+            next.get_id()
+        );
+    }
+}