From e7ccd1a71eb9fe3425d92a0070eb6c6b60286cd4 Mon Sep 17 00:00:00 2001
From: Dmitry Savintsev <dsavints@gmail.com>
Date: Tue, 10 Jan 2023 15:34:44 +0100
Subject: [PATCH] include and use clap only if needed

Signed-off-by: Dmitry Savintsev <dsavints@gmail.com>
---
 cargo-generate.toml                |  3 +++
 pre-script.rhai                    |  2 ++
 {{project-name}}-common/src/lib.rs |  2 +-
 {{project-name}}/Cargo.toml        |  4 +++-
 {{project-name}}/src/main.rs       | 26 +++++++++++---------------
 5 files changed, 20 insertions(+), 17 deletions(-)
 create mode 100644 pre-script.rhai

diff --git a/cargo-generate.toml b/cargo-generate.toml
index b4c4e31..a977b33 100644
--- a/cargo-generate.toml
+++ b/cargo-generate.toml
@@ -73,3 +73,6 @@ regex = "^[a-z_]+$"
 type = "string"
 prompt = "Which lsm hook? (e.g file_open, task_alloc) You can find a list of hooks in include/linux/lsm_hooks.h in the kernel source tree."
 regex = "^[a-z_]+$"
+
+[hooks]
+pre = ["pre-script.rhai"]
diff --git a/pre-script.rhai b/pre-script.rhai
new file mode 100644
index 0000000..65fa2b5
--- /dev/null
+++ b/pre-script.rhai
@@ -0,0 +1,2 @@
+let program_types_with_opts = ["classifier", "cgroup_skb", "cgroup_sockopt", "cgroup_sysctl",  "sock_ops", "uprobe", "uretprobe", "xdp"];
+variable::set("program_types_with_opts", program_types_with_opts);
diff --git a/{{project-name}}-common/src/lib.rs b/{{project-name}}-common/src/lib.rs
index 4100b5e..1bc3620 100644
--- a/{{project-name}}-common/src/lib.rs
+++ b/{{project-name}}-common/src/lib.rs
@@ -12,4 +12,4 @@ pub struct SockKey {
 
 #[cfg(feature = "user")]
 unsafe impl aya::Pod for SockKey {}
-{%- endif -%}
+{%- endif %}
diff --git a/{{project-name}}/Cargo.toml b/{{project-name}}/Cargo.toml
index 14f7f80..18be02f 100644
--- a/{{project-name}}/Cargo.toml
+++ b/{{project-name}}/Cargo.toml
@@ -6,10 +6,12 @@ publish = false
 
 [dependencies]
 aya = { version = ">=0.11", features=["async_tokio"] }
+{% if program_types_with_opts contains program_type -%}
+clap = { version = "4.0", features = ["derive"] }
+{% endif -%}
 aya-log = "0.1"
 {{project-name}}-common = { path = "../{{project-name}}-common", features=["user"] }
 anyhow = "1.0.42"
-clap = { version = "4.0", features = ["derive"] }
 env_logger = "0.10"
 {%- if program_type == "uprobe" %}
 libc = "0.2"
diff --git a/{{project-name}}/src/main.rs b/{{project-name}}/src/main.rs
index 07a95fc..ebb3ad8 100644
--- a/{{project-name}}/src/main.rs
+++ b/{{project-name}}/src/main.rs
@@ -1,4 +1,3 @@
-use aya::{include_bytes_aligned, Bpf};
 {% case program_type -%}
 {%- when "kprobe", "kretprobe" -%}
 use aya::programs::KProbe;
@@ -41,38 +40,35 @@ use aya::programs::SocketFilter;
 {%- when "raw_tracepoint" -%}
 use aya::programs::RawTracePoint;
 {%- endcase %}
+use aya::{include_bytes_aligned, Bpf};
 use aya_log::BpfLogger;
+{% if program_types_with_opts contains program_type -%}
 use clap::Parser;
+{% endif -%}
 use log::{info, warn};
 use tokio::signal;
 
-{% case program_type %}
-{%- when
-    "xdp", "classifier", "sock_ops", "cgroup_skb", "cgroup_sysctl", "cgroup_sockopt", "uprobe", "uretprobe" -%}
+{% if program_types_with_opts contains program_type -%}
 #[derive(Debug, Parser)]
 struct Opt {
-    {% if program_type == "xdp" or program_type == "classifier" -%}
+{%- if program_type == "xdp" or program_type == "classifier" %}
     #[clap(short, long, default_value = "eth0")]
     iface: String,
-    {%- elsif program_type == "sock_ops" or program_type == "cgroup_skb" or program_type == "cgroup_sysctl" or program_type == "cgroup_sockopt" -%}
+{% elsif program_type == "sock_ops" or program_type == "cgroup_skb" or program_type == "cgroup_sysctl" or program_type == "cgroup_sockopt" %}
     #[clap(short, long, default_value = "/sys/fs/cgroup/unified")]
     cgroup_path: String,
-    {%- elsif program_type == "uprobe" or program_type == "uretprobe" -%}
+{% elsif program_type == "uprobe" or program_type == "uretprobe" %}
     #[clap(short, long)]
     pid: Option<i32>
-    {%- endif %}
+{% endif -%}
 }
-{%- endcase %}
 
+{% endif -%}
 #[tokio::main]
 async fn main() -> Result<(), anyhow::Error> {
-    {% case program_type %}
-    {%- when
-        "xdp", "classifier", "sock_ops", "cgroup_skb", "cgroup_sysctl", "cgroup_sockopt", "uprobe", "uretprobe" -%}
+{%- if program_types_with_opts contains program_type %}
     let opt = Opt::parse();
-
-    {%- endcase %}
-
+{% endif %}
     env_logger::init();
 
     // This will include your eBPF object file as raw bytes at compile-time and load it at