thermald: use Redox /scheme/sys/msr for CPU temperature reads

local/recipes/system/thermald/source/src/main.rs

@@ -189,27 +189,55 @@ fn zone_name_for_entry(entry: &fs::DirEntry) -> Option<String> {
 }
 
 fn read_msr(cpu: u32, msr: u32) -> Option<u64> {
-    let path = format!("/dev/cpu/{cpu}/msr");
-    let mut file = fs::File::open(&path).ok()?;
-    let mut buf = [0u8; 8];
-    use std::io::{Read, Seek, SeekFrom};
-    file.seek(SeekFrom::Start(msr as u64)).ok()?;
-    file.read_exact(&mut buf).ok()?;
-    Some(u64::from_le_bytes(buf))
+    #[cfg(target_os = "redox")]
+    {
+        let path = format!("/scheme/sys/msr/{}/0x{:x}", cpu, msr);
+        let mut file = fs::File::open(&path).ok()?;
+        let mut buf = [0u8; 8];
+        use std::io::Read;
+        file.read_exact(&mut buf).ok()?;
+        Some(u64::from_le_bytes(buf))
+    }
+    #[cfg(not(target_os = "redox"))]
+    {
+        let path = format!("/dev/cpu/{cpu}/msr");
+        let mut file = fs::File::open(&path).ok()?;
+        let mut buf = [0u8; 8];
+        use std::io::{Read, Seek, SeekFrom};
+        file.seek(SeekFrom::Start(msr as u64)).ok()?;
+        file.read_exact(&mut buf).ok()?;
+        Some(u64::from_le_bytes(buf))
+    }
 }
 
 fn cpu_count() -> u32 {
-    let mut count = 0u32;
-    if let Ok(entries) = fs::read_dir("/dev/cpu") {
-        for entry in entries.filter_map(Result::ok) {
-            if let Ok(name) = entry.file_name().into_string() {
-                if name.parse::<u32>().is_ok() {
-                    count += 1;
+    #[cfg(target_os = "redox")]
+    {
+        if let Ok(data) = fs::read_to_string("/scheme/sys/cpu") {
+            for line in data.lines() {
+                if let Some(rest) = line.strip_prefix("CPUs: ") {
+                    if let Ok(n) = rest.trim().parse::<u32>() {
+                        return n.max(1);
+                    }
                 }
             }
         }
+        1
+    }
+    #[cfg(not(target_os = "redox"))]
+    {
+        let mut count = 0u32;
+        if let Ok(entries) = fs::read_dir("/dev/cpu") {
+            for entry in entries.filter_map(Result::ok) {
+                if let Ok(name) = entry.file_name().into_string() {
+                    if name.parse::<u32>().is_ok() {
+                        count += 1;
+                    }
+                }
+            }
+        }
+        count.max(1)
     }
-    count.max(1)
 }
 
 fn read_cpu_temperature(cpu: u32) -> Option<f64> {