treewide: move application-specific crates to crates/

Signed-off-by: NotAShelf <raf@notashelf.dev>
Change-Id: I47d36cb7d1dec5ab0c892190015cfc576a6a6964

crates/pscand-macros/Cargo.toml

@@ -0,0 +1,14 @@
+[package]
+name = "pscand-macros"
+version.workspace = true
+edition.workspace = true
+license.workspace = true
+authors.workspace = true
+
+[lib]
+proc-macro = true
+
+[dependencies]
+proc-macro2 = "1"
+quote = "1"
+syn = { version = "2", features = ["full"] }

crates/pscand-macros/src/lib.rs

@@ -0,0 +1,64 @@
+use proc_macro::TokenStream;
+use quote::quote;
+use syn::{parse_macro_input, ItemFn};
+
+#[proc_macro_attribute]
+pub fn scanner(name: TokenStream, input: TokenStream) -> TokenStream {
+    let name_str = parse_macro_input!(name as syn::LitStr).value();
+    let input = parse_macro_input!(input as ItemFn);
+
+    let _fn_name = input.sig.ident.clone();
+    let body = &input.block;
+
+    let result = quote! {
+        #[no_mangle]
+        pub extern "C" fn pscand_scanner() -> *mut std::os::raw::c_void {
+            struct ScannerImpl;
+
+            impl pscand_core::Scanner for ScannerImpl {
+                fn name(&self) -> &'static str {
+                    #name_str
+                }
+
+                fn interval(&self) -> std::time::Duration {
+                    std::time::Duration::from_secs(1)
+                }
+
+                fn init(&mut self, _config: &toml::Value) -> pscand_core::Result<()> {
+                    Ok(())
+                }
+
+                fn collect(&self) -> pscand_core::Result<std::collections::HashMap<String, pscand_core::MetricValue>> {
+                    #body
+                }
+
+                fn cleanup(&mut self) -> pscand_core::Result<()> {
+                    Ok(())
+                }
+            }
+
+            let handle = unsafe { pscand_core::register_scanner(Box::new(ScannerImpl)) };
+            handle as *mut std::os::raw::c_void
+        }
+    };
+
+    result.into()
+}
+
+#[proc_macro]
+pub fn register_scanner(input: TokenStream) -> TokenStream {
+    let input = parse_macro_input!(input as ItemFn);
+    let fn_name = input.sig.ident.clone();
+
+    let result = quote! {
+        #input
+
+        #[no_mangle]
+        pub extern "C" fn pscand_scanner() -> *mut std::os::raw::c_void {
+            let handle = unsafe { pscand_core::register_scanner(Box::new(#fn_name())) };
+            handle as *mut std::os::raw::c_void
+        }
+    };
+
+    result.into()
+}