scanner: make plugin interface ffi-safe with handle-based registry

Signed-off-by: NotAShelf <raf@notashelf.dev>
Change-Id: I8e4790db3cc29f84f4e0d7d8eff36c2c6a6a6964

scanners/scanner-power/src/lib.rs

@@ -1,4 +1,3 @@
-#![allow(improper_ctypes)]
 use pscand_core::helpers::PowerHelper;
 use pscand_core::scanner::{MetricValue, Scanner};
 use std::collections::HashMap;
@@ -6,9 +5,9 @@ use std::time::Duration;
 
 struct PowerScanner;
 
-#[unsafe(no_mangle)]
-pub extern "C" fn pscand_scanner() -> Box<dyn Scanner> {
-    Box::new(PowerScanner)
+#[no_mangle]
+pub extern "C" fn pscand_scanner() -> *mut std::os::raw::c_void {
+    Box::into_raw(Box::new(PowerScanner)) as *mut std::os::raw::c_void
 }
 
 impl Default for PowerScanner {
@@ -52,7 +51,7 @@ impl Scanner for PowerScanner {
             );
             metrics.insert(
                 "battery_status".to_string(),
-                MetricValue::from_str(&battery.status),
+                MetricValue::from_string(&battery.status),
             );
         }
 
@@ -61,7 +60,7 @@ impl Scanner for PowerScanner {
                 if let Some(status) = info.get("status") {
                     metrics.insert(
                         format!("supply_{}_status", name),
-                        MetricValue::from_str(status),
+                        MetricValue::from_string(status),
                     );
                 }
                 if let Some(online) = info.get("online") {
@@ -82,7 +81,10 @@ impl Scanner for PowerScanner {
         }
 
         if let Ok(state) = PowerHelper::suspend_state() {
-            metrics.insert("suspend_state".to_string(), MetricValue::from_str(&state));
+            metrics.insert(
+                "suspend_state".to_string(),
+                MetricValue::from_string(&state),
+            );
         }
 
         Ok(metrics)

scanners/scanner-proc/src/lib.rs

@@ -5,9 +5,9 @@ use std::time::Duration;
 
 struct ProcScanner;
 
-#[unsafe(no_mangle)]
-pub extern "C" fn pscand_scanner() -> Box<dyn Scanner> {
-    Box::new(ProcScanner)
+#[no_mangle]
+pub extern "C" fn pscand_scanner() -> *mut std::os::raw::c_void {
+    Box::into_raw(Box::new(ProcScanner)) as *mut std::os::raw::c_void
 }
 
 impl Default for ProcScanner {
@@ -72,7 +72,7 @@ impl Scanner for ProcScanner {
                 }
                 metrics.insert(
                     "zombie_processes".to_string(),
-                    MetricValue::from_str(zombie_info.join(",")),
+                    MetricValue::from_string(zombie_info.join(",")),
                 );
             }
         }
@@ -81,7 +81,7 @@ impl Scanner for ProcScanner {
             for (i, proc) in top_mem.iter().enumerate() {
                 metrics.insert(
                     format!("top_mem_{}_name", i + 1),
-                    MetricValue::from_str(&proc.name),
+                    MetricValue::from_string(&proc.name),
                 );
                 metrics.insert(
                     format!("top_mem_{}_mb", i + 1),

scanners/scanner-sensor/src/lib.rs

@@ -1,4 +1,3 @@
-#![allow(improper_ctypes)]
 use pscand_core::helpers::SensorHelper;
 use pscand_core::scanner::{MetricValue, Scanner};
 use pscand_core::Result;
@@ -7,9 +6,9 @@ use std::time::Duration;
 
 struct SensorScanner;
 
-#[unsafe(no_mangle)]
-pub extern "C" fn pscand_scanner() -> Box<dyn Scanner> {
-    Box::new(SensorScanner)
+#[no_mangle]
+pub extern "C" fn pscand_scanner() -> *mut std::os::raw::c_void {
+    Box::into_raw(Box::new(SensorScanner)) as *mut std::os::raw::c_void
 }
 
 impl Default for SensorScanner {

scanners/scanner-system/src/lib.rs

@@ -1,23 +1,17 @@
-#![allow(improper_ctypes)]
 use pscand_core::helpers::{ResourceHelper, SystemHelper};
 use pscand_core::scanner::{MetricValue, Scanner};
 use pscand_core::Result;
 use std::collections::HashMap;
 use std::time::Duration;
 
+#[derive(Default)]
 struct SystemScanner {
     _prev_cpu: Option<HashMap<String, f64>>,
 }
 
-impl Default for SystemScanner {
-    fn default() -> Self {
-        Self { _prev_cpu: None }
-    }
-}
-
-#[unsafe(no_mangle)]
-pub extern "C" fn pscand_scanner() -> Box<dyn Scanner> {
-    Box::new(SystemScanner::default())
+#[no_mangle]
+pub extern "C" fn pscand_scanner() -> *mut std::os::raw::c_void {
+    Box::into_raw(Box::new(SystemScanner::default())) as *mut std::os::raw::c_void
 }
 
 impl Scanner for SystemScanner {