fs: fix read() typesig

config.toml

@@ -0,0 +1,2 @@
+[[rule]]
+priority = 0

src/config.rs

@@ -255,7 +255,7 @@ pub enum Expression {
 pub struct Rule {
     priority: u8,
 
-    #[serde(default, skip_serializing_if = "is_default")]
+    #[serde(default, rename = "if", skip_serializing_if = "is_default")]
     if_: Expression,
 
     #[serde(default, skip_serializing_if = "is_default")]
@@ -265,7 +265,7 @@ pub struct Rule {
 }
 
 #[derive(Serialize, Deserialize, Default, Debug, Clone, PartialEq)]
-#[serde(transparent, default, rename_all = "kebab-case")]
+#[serde(default, rename_all = "kebab-case")]
 pub struct DaemonConfig {
     #[serde(rename = "rule")]
     rules: Vec<Rule>,

src/cpu.rs

@@ -1,33 +1,9 @@
 use anyhow::{Context, bail};
 use yansi::Paint as _;
 
-use std::{fmt, fs, path::Path, string::ToString};
+use std::{fmt, string::ToString};
 
-fn exists(path: impl AsRef<Path>) -> bool {
+use crate::fs;
-    let path = path.as_ref();
-
-    path.exists()
-}
-
-// Not doing any anyhow stuff here as all the calls of this ignore errors.
-fn read_u64(path: impl AsRef<Path>) -> anyhow::Result<u64> {
-    let path = path.as_ref();
-
-    let content = fs::read_to_string(path)?;
-
-    Ok(content.trim().parse()?)
-}
-
-fn write(path: impl AsRef<Path>, value: &str) -> anyhow::Result<()> {
-    let path = path.as_ref();
-
-    fs::write(path, value).with_context(|| {
-        format!(
-            "failed to write '{value}' to '{path}'",
-            path = path.display(),
-        )
-    })
-}
 
 #[derive(Debug, Clone, Copy)]
 pub struct Cpu {
@@ -96,11 +72,11 @@ impl Cpu {
     pub fn rescan(&mut self) -> anyhow::Result<()> {
         let Self { number, .. } = self;
 
-        if !exists(format!("/sys/devices/system/cpu/cpu{number}")) {
+        if !fs::exists(format!("/sys/devices/system/cpu/cpu{number}")) {
             bail!("{self} does not exist");
         }
 
-        let has_cpufreq = exists(format!("/sys/devices/system/cpu/cpu{number}/cpufreq"));
+        let has_cpufreq = fs::exists(format!("/sys/devices/system/cpu/cpu{number}/cpufreq"));
 
         self.has_cpufreq = has_cpufreq;
 
@@ -110,7 +86,7 @@ impl Cpu {
     pub fn get_available_governors(&self) -> Vec<String> {
         let Self { number, .. } = self;
 
-        let Ok(content) = fs::read_to_string(format!(
+        let Some(Ok(content)) = fs::read(format!(
             "/sys/devices/system/cpu/cpu{number}/cpufreq/scaling_available_governors"
         )) else {
             return Vec::new();
@@ -137,7 +113,7 @@ impl Cpu {
             );
         }
 
-        write(
+        fs::write(
             format!("/sys/devices/system/cpu/cpu{number}/cpufreq/scaling_governor"),
             governor,
         )
@@ -151,7 +127,7 @@ impl Cpu {
     pub fn get_available_epps(&self) -> Vec<String> {
         let Self { number, .. } = self;
 
-        let Ok(content) = fs::read_to_string(format!(
+        let Some(Ok(content)) = fs::read(format!(
             "/sys/devices/system/cpu/cpu{number}/cpufreq/energy_performance_available_preferences"
         )) else {
             return Vec::new();
@@ -175,7 +151,7 @@ impl Cpu {
             );
         }
 
-        write(
+        fs::write(
             format!("/sys/devices/system/cpu/cpu{number}/cpufreq/energy_performance_preference"),
             epp,
         )
@@ -226,7 +202,7 @@ impl Cpu {
             );
         }
 
-        write(
+        fs::write(
             format!("/sys/devices/system/cpu/cpu{number}/cpufreq/energy_performance_bias"),
             epb,
         )
@@ -244,7 +220,7 @@ impl Cpu {
         let frequency_khz = frequency_mhz * 1000;
         let frequency_khz = frequency_khz.to_string();
 
-        write(
+        fs::write(
             format!("/sys/devices/system/cpu/cpu{number}/cpufreq/scaling_min_freq"),
             &frequency_khz,
         )
@@ -256,7 +232,7 @@ impl Cpu {
     fn validate_frequency_minimum(&self, new_frequency_mhz: u64) -> anyhow::Result<()> {
         let Self { number, .. } = self;
 
-        let Ok(minimum_frequency_khz) = read_u64(format!(
+        let Ok(minimum_frequency_khz) = fs::read_u64(format!(
             "/sys/devices/system/cpu/cpu{number}/cpufreq/scaling_min_freq"
         )) else {
             // Just let it pass if we can't find anything.
@@ -282,7 +258,7 @@ impl Cpu {
         let frequency_khz = frequency_mhz * 1000;
         let frequency_khz = frequency_khz.to_string();
 
-        write(
+        fs::write(
             format!("/sys/devices/system/cpu/cpu{number}/cpufreq/scaling_max_freq"),
             &frequency_khz,
         )
@@ -294,7 +270,7 @@ impl Cpu {
     fn validate_frequency_maximum(&self, new_frequency_mhz: u64) -> anyhow::Result<()> {
         let Self { number, .. } = self;
 
-        let Ok(maximum_frequency_khz) = read_u64(format!(
+        let Ok(maximum_frequency_khz) = fs::read_u64(format!(
             "/sys/devices/system/cpu/cpu{number}/cpufreq/scaling_min_freq"
         )) else {
             // Just let it pass if we can't find anything.
@@ -331,16 +307,16 @@ impl Cpu {
         let generic_boost_path = "/sys/devices/system/cpu/cpufreq/boost";
 
         // Try each boost control path in order of specificity
-        if write(intel_boost_path_negated, value_boost_negated).is_ok() {
+        if fs::write(intel_boost_path_negated, value_boost_negated).is_ok() {
             return Ok(());
         }
-        if write(amd_boost_path, value_boost).is_ok() {
+        if fs::write(amd_boost_path, value_boost).is_ok() {
             return Ok(());
         }
-        if write(msr_boost_path, value_boost).is_ok() {
+        if fs::write(msr_boost_path, value_boost).is_ok() {
             return Ok(());
         }
-        if write(generic_boost_path, value_boost).is_ok() {
+        if fs::write(generic_boost_path, value_boost).is_ok() {
             return Ok(());
         }
 
@@ -348,7 +324,7 @@ impl Cpu {
         if Self::all()?.iter().any(|cpu| {
             let Cpu { number, .. } = cpu;
 
-            write(
+            fs::write(
                 format!("/sys/devices/system/cpu/cpu{number}/cpufreq/boost"),
                 value_boost,
             )

src/daemon.rs

@@ -1,9 +1,15 @@
 use std::{
     collections::VecDeque,
     ops,
+    sync::{
+        Arc,
+        atomic::{AtomicBool, Ordering},
+    },
     time::{Duration, Instant},
 };
 
+use anyhow::Context;
+
 use crate::config;
 
 /// Calculate the idle time multiplier based on system idle time.
@@ -33,13 +39,17 @@ struct Daemon {
     /// Last time when there was user activity.
     last_user_activity: Instant,
 
+    /// The last computed polling interval.
+    last_polling_interval: Option<Duration>,
+
+    /// Whether if we are charging right now.
+    charging: bool,
+
     /// CPU usage and temperature log.
     cpu_log: VecDeque<CpuLog>,
 
     /// Power supply status log.
     power_supply_log: VecDeque<PowerSupplyLog>,
-
-    charging: bool,
 }
 
 struct CpuLog {
@@ -167,7 +177,7 @@ impl Daemon {
 }
 
 impl Daemon {
-    fn polling_interval(&self) -> Duration {
+    fn polling_interval(&mut self) -> Duration {
         let mut interval = Duration::from_secs(5);
 
         // We are on battery, so we must be more conservative with our polling.
@@ -185,6 +195,8 @@ impl Daemon {
                     }
                 }
 
+                // If we can't deterine the discharge rate, that means that
+                // we were very recently started. Which is user activity.
                 None => {
                     interval *= 2;
                 }
@@ -213,10 +225,38 @@ impl Daemon {
             }
         }
 
-        todo!("implement rest from daemon_old.rs")
+        let interval = match self.last_polling_interval {
+            Some(last_interval) => Duration::from_secs_f64(
+                // 30% of current computed interval, 70% of last interval.
+                interval.as_secs_f64() * 0.3 + last_interval.as_secs_f64() * 0.7,
+            ),
+
+            None => interval,
+        };
+
+        let interval = Duration::from_secs_f64(interval.as_secs_f64().clamp(1.0, 30.0));
+
+        self.last_polling_interval = Some(interval);
+
+        interval
     }
 }
 
 pub fn run(config: config::DaemonConfig) -> anyhow::Result<()> {
+    log::info!("starting daemon...");
+
+    let cancelled = Arc::new(AtomicBool::new(false));
+
+    let cancelled_ = Arc::clone(&cancelled);
+    ctrlc::set_handler(move || {
+        log::info!("received shutdown signal");
+        cancelled_.store(true, Ordering::SeqCst);
+    })
+    .context("failed to set Ctrl-C handler")?;
+
+    while !cancelled.load(Ordering::SeqCst) {}
+
+    log::info!("exiting...");
+
     Ok(())
 }

src/daemon_old.rs

@@ -12,143 +12,6 @@ use std::sync::Arc;
 use std::sync::atomic::{AtomicBool, Ordering};
 use std::time::{Duration, Instant};
 
-/// Parameters for computing optimal polling interval
-struct IntervalParams {
-    /// Base polling interval in seconds
-    base_interval: u64,
-    /// Minimum allowed polling interval in seconds
-    min_interval: u64,
-    /// Maximum allowed polling interval in seconds
-    max_interval: u64,
-    /// How rapidly CPU usage is changing
-    cpu_volatility: f32,
-    /// How rapidly temperature is changing
-    temp_volatility: f32,
-    /// Battery discharge rate in %/hour if available
-    battery_discharge_rate: Option<f32>,
-    /// Time since last detected user activity
-    last_user_activity: Duration,
-    /// Whether the system appears to be idle
-    is_system_idle: bool,
-    /// Whether the system is running on battery power
-    on_battery: bool,
-}
-
-/// Calculate the idle time multiplier based on system idle duration
-///
-/// Returns a multiplier between 1.0 and 5.0 (capped):
-/// - For idle times < 2 minutes: Linear interpolation from 1.0 to 2.0
-/// - For idle times >= 2 minutes: Logarithmic scaling (1.0 + log2(minutes))
-fn idle_multiplier(idle_secs: u64) -> f32 {
-    if idle_secs == 0 {
-        return 1.0; // No idle time, no multiplier effect
-    }
-
-    let idle_factor = if idle_secs < 120 {
-        // Less than 2 minutes (0 to 119 seconds)
-        // Linear interpolation from 1.0 (at 0s) to 2.0 (at 120s)
-        1.0 + (idle_secs as f32) / 120.0
-    } else {
-        // 2 minutes (120 seconds) or more
-        let idle_time_minutes = idle_secs / 60;
-        // Logarithmic scaling: 1.0 + log2(minutes)
-        1.0 + (idle_time_minutes as f32).log2().max(0.5)
-    };
-
-    // Cap the multiplier to avoid excessive intervals
-    idle_factor.min(5.0) // max factor of 5x
-}
-
-/// Calculate optimal polling interval based on system conditions and history
-///
-/// Returns Ok with the calculated interval, or Err if the configuration is invalid
-fn compute_new(params: &IntervalParams, system_history: &SystemHistory) -> anyhow::Result<u64> {
-    // Use the centralized validation function
-    validate_poll_intervals(params.min_interval, params.max_interval)?;
-
-    // Start with base interval
-    let mut adjusted_interval = params.base_interval;
-
-    // If we're on battery, we want to be more aggressive about saving power
-    if params.on_battery {
-        // Apply a multiplier based on battery discharge rate
-        if let Some(discharge_rate) = params.battery_discharge_rate {
-            if discharge_rate > 20.0 {
-                // High discharge rate - increase polling interval significantly (3x)
-                adjusted_interval = adjusted_interval.saturating_mul(3);
-            } else if discharge_rate > 10.0 {
-                // Moderate discharge - double polling interval (2x)
-                adjusted_interval = adjusted_interval.saturating_mul(2);
-            } else {
-                // Low discharge rate - increase by 50% (multiply by 3/2)
-                adjusted_interval = adjusted_interval.saturating_mul(3).saturating_div(2);
-            }
-        } else {
-            // If we don't know discharge rate, use a conservative multiplier (2x)
-            adjusted_interval = adjusted_interval.saturating_mul(2);
-        }
-    }
-
-    // Adjust for system idleness
-    if params.is_system_idle {
-        let idle_time_seconds = params.last_user_activity.as_secs();
-
-        // Apply adjustment only if the system has been idle for a non-zero duration
-        if idle_time_seconds > 0 {
-            let idle_factor = idle_multiplier(idle_time_seconds);
-
-            log::debug!(
-                "System idle for {} seconds (approx. {} minutes), applying idle factor: {:.2}x",
-                idle_time_seconds,
-                (idle_time_seconds as f32 / 60.0).round(),
-                idle_factor
-            );
-
-            // Convert f32 multiplier to integer-safe math
-            // Multiply by a large number first, then divide to maintain precision
-            // Use 1000 as the scaling factor to preserve up to 3 decimal places
-            let scaling_factor = 1000;
-            let scaled_factor = (idle_factor * scaling_factor as f32) as u64;
-            adjusted_interval = adjusted_interval
-                .saturating_mul(scaled_factor)
-                .saturating_div(scaling_factor);
-        }
-        // If idle_time_seconds is 0, no factor is applied by this block
-    }
-
-    // Adjust for CPU/temperature volatility
-    if params.cpu_volatility > 10.0 || params.temp_volatility > 2.0 {
-        // For division by 2 (halving the interval), we can safely use integer division
-        adjusted_interval = (adjusted_interval / 2).max(1);
-    }
-
-    // Enforce a minimum of 1 second to prevent busy loops, regardless of params.min_interval
-    let min_safe_interval = params.min_interval.max(1);
-    let new_interval = adjusted_interval.clamp(min_safe_interval, params.max_interval);
-
-    // Blend the new interval with the cached value if available
-    let blended_interval = if let Some(cached) = system_history.last_computed_interval {
-        // Use a weighted average: 70% previous value, 30% new value
-        // This smooths out drastic changes in polling frequency
-        const PREVIOUS_VALUE_WEIGHT: u128 = 7; // 70%
-        const NEW_VALUE_WEIGHT: u128 = 3; // 30%
-        const TOTAL_WEIGHT: u128 = PREVIOUS_VALUE_WEIGHT + NEW_VALUE_WEIGHT; // 10
-
-        // XXX: Use u128 arithmetic to avoid overflow with large interval values
-        let result = (u128::from(cached) * PREVIOUS_VALUE_WEIGHT
-            + u128::from(new_interval) * NEW_VALUE_WEIGHT)
-            / TOTAL_WEIGHT;
-
-        result as u64
-    } else {
-        new_interval
-    };
-
-    // Blended result still needs to respect the configured bounds
-    // Again enforce minimum of 1 second regardless of params.min_interval
-    Ok(blended_interval.clamp(min_safe_interval, params.max_interval))
-}
-
 /// Tracks historical system data for "advanced" adaptive polling
 #[derive(Debug)]
 struct SystemHistory {
@@ -174,23 +37,6 @@ struct SystemHistory {
     last_computed_interval: Option<u64>,
 }
 
-impl Default for SystemHistory {
-    fn default() -> Self {
-        Self {
-            cpu_usage_history: VecDeque::new(),
-            temperature_history: VecDeque::new(),
-            last_user_activity: Instant::now(),
-            last_battery_percentage: None,
-            last_battery_timestamp: None,
-            battery_discharge_rate: None,
-            state_durations: std::collections::HashMap::new(),
-            last_state_change: Instant::now(),
-            current_state: SystemState::default(),
-            last_computed_interval: None,
-        }
-    }
-}
-
 impl SystemHistory {
     /// Update system history with new report data
     fn update(&mut self, report: &SystemReport) {
@@ -354,45 +200,6 @@ impl SystemHistory {
             self.cpu_usage_history.iter().sum::<f32>() / self.cpu_usage_history.len() as f32;
         recent_avg < 10.0 && self.get_cpu_volatility() < 5.0
     }
-
-    /// Calculate optimal polling interval based on system conditions
-    fn calculate_optimal_interval(
-        &self,
-        config: &AppConfig,
-        on_battery: bool,
-    ) -> anyhow::Result<u64> {
-        let params = IntervalParams {
-            base_interval: config.daemon.poll_interval_sec,
-            min_interval: config.daemon.min_poll_interval_sec,
-            max_interval: config.daemon.max_poll_interval_sec,
-            cpu_volatility: self.get_cpu_volatility(),
-            temp_volatility: self.get_temperature_volatility(),
-            battery_discharge_rate: self.battery_discharge_rate,
-            last_user_activity: self.last_user_activity.elapsed(),
-            is_system_idle: self.is_system_idle(),
-            on_battery,
-        };
-
-        compute_new(&params, self)
-    }
-}
-
-/// Validates that poll interval configuration is consistent
-/// Returns Ok if configuration is valid, Err with a descriptive message if invalid
-fn validate_poll_intervals(min_interval: u64, max_interval: u64) -> anyhow::Result<()> {
-    if min_interval < 1 {
-        bail!("min_interval must be ≥ 1");
-    }
-    if max_interval < 1 {
-        bail!("max_interval must be ≥ 1");
-    }
-    if max_interval >= min_interval {
-        Ok(())
-    } else {
-        bail!(
-            "Invalid interval configuration: max_interval ({max_interval}) is less than min_interval ({min_interval})"
-        );
-    }
 }
 
 /// Run the daemon
@@ -561,36 +368,6 @@ pub fn run_daemon(config: AppConfig) -> anyhow::Result<()> {
     Ok(())
 }
 
-/// Write current system stats to a file for --stats to read
-fn write_stats_file(path: &str, report: &SystemReport) -> Result<(), std::io::Error> {
-    let mut file = File::create(path)?;
-
-    writeln!(file, "timestamp={:?}", report.timestamp)?;
-
-    // CPU info
-    writeln!(file, "governor={:?}", report.cpu_global.current_governor)?;
-    writeln!(file, "turbo={:?}", report.cpu_global.turbo_status)?;
-    if let Some(temp) = report.cpu_global.average_temperature_celsius {
-        writeln!(file, "cpu_temp={temp:.1}")?;
-    }
-
-    // Battery info
-    if !report.batteries.is_empty() {
-        let battery = &report.batteries[0];
-        writeln!(file, "ac_power={}", battery.ac_connected)?;
-        if let Some(cap) = battery.capacity_percent {
-            writeln!(file, "battery_percent={cap}")?;
-        }
-    }
-
-    // System load
-    writeln!(file, "load_1m={:.2}", report.system_load.load_avg_1min)?;
-    writeln!(file, "load_5m={:.2}", report.system_load.load_avg_5min)?;
-    writeln!(file, "load_15m={:.2}", report.system_load.load_avg_15min)?;
-
-    Ok(())
-}
-
 /// Simplified system state used for determining when to adjust polling interval
 #[derive(Debug, PartialEq, Eq, Clone, Hash, Default)]
 enum SystemState {

src/fs.rs

@@ -0,0 +1,55 @@
+use std::{fs, io, path::Path};
+
+use anyhow::Context;
+
+pub fn exists(path: impl AsRef<Path>) -> bool {
+    let path = path.as_ref();
+
+    path.exists()
+}
+
+pub fn read_dir(path: impl AsRef<Path>) -> anyhow::Result<fs::ReadDir> {
+    let path = path.as_ref();
+
+    fs::read_dir(path)
+        .with_context(|| format!("failed to read directory '{path}'", path = path.display()))
+}
+
+pub fn read(path: impl AsRef<Path>) -> Option<anyhow::Result<String>> {
+    let path = path.as_ref();
+
+    match fs::read_to_string(path) {
+        Ok(string) => Some(Ok(string)),
+
+        Err(error) if error.kind() == io::ErrorKind::NotFound => None,
+
+        Err(error) => Some(
+            Err(error).with_context(|| format!("failed to read '{path}", path = path.display())),
+        ),
+    }
+}
+
+pub fn read_u64(path: impl AsRef<Path>) -> anyhow::Result<u64> {
+    let path = path.as_ref();
+
+    let content = fs::read_to_string(path)
+        .with_context(|| format!("failed to read '{path}'", path = path.display()))?;
+
+    Ok(content.trim().parse().with_context(|| {
+        format!(
+            "failed to parse contents of '{path}' as a unsigned number",
+            path = path.display(),
+        )
+    })?)
+}
+
+pub fn write(path: impl AsRef<Path>, value: &str) -> anyhow::Result<()> {
+    let path = path.as_ref();
+
+    fs::write(path, value).with_context(|| {
+        format!(
+            "failed to write '{value}' to '{path}'",
+            path = path.display(),
+        )
+    })
+}

src/main.rs

@@ -1,10 +1,14 @@
+mod cpu;
+mod power_supply;
+mod system;
+
+mod fs;
+
 mod config;
 // mod core;
-mod cpu;
 mod daemon;
 // mod engine;
 // mod monitor;
-mod power_supply;
 
 use anyhow::Context;
 use clap::Parser as _;

src/power_supply.rs

@@ -1,22 +1,12 @@
-use anyhow::{Context, bail};
+use anyhow::{Context, anyhow, bail};
 use yansi::Paint as _;
 
 use std::{
-    fmt, fs,
+    fmt,
     path::{Path, PathBuf},
 };
 
-// TODO: Migrate to central utils file. Same exists in cpu.rs.
+use crate::fs;
-fn write(path: impl AsRef<Path>, value: &str) -> anyhow::Result<()> {
-    let path = path.as_ref();
-
-    fs::write(path, value).with_context(|| {
-        format!(
-            "failed to write '{value}' to '{path}'",
-            path = path.display(),
-        )
-    })
-}
 
 /// Represents a pattern of path suffixes used to control charge thresholds
 /// for different device vendors.
@@ -136,7 +126,8 @@ impl PowerSupply {
     fn get_type(&self) -> anyhow::Result<String> {
         let type_path = self.path.join("type");
 
-        let type_ = fs::read_to_string(&type_path)
+        let type_ = fs::read(&type_path)
+            .with_context(|| format!("'{path}' doesn't exist", path = type_path.display()))?
             .with_context(|| format!("failed to read '{path}'", path = type_path.display()))?;
 
         Ok(type_)
@@ -180,9 +171,9 @@ impl PowerSupply {
     }
 
     pub fn set_charge_threshold_start(&self, charge_threshold_start: u8) -> anyhow::Result<()> {
-        write(
+        fs::write(
             &self.charge_threshold_path_start().ok_or_else(|| {
-                anyhow::anyhow!(
+                anyhow!(
                     "power supply '{name}' does not support changing charge threshold levels",
                     name = self.name,
                 )
@@ -197,9 +188,9 @@ impl PowerSupply {
     }
 
     pub fn set_charge_threshold_end(&self, charge_threshold_end: u8) -> anyhow::Result<()> {
-        write(
+        fs::write(
             &self.charge_threshold_path_end().ok_or_else(|| {
-                anyhow::anyhow!(
+                anyhow!(
                     "power supply '{name}' does not support changing charge threshold levels",
                     name = self.name,
                 )
@@ -216,7 +207,7 @@ impl PowerSupply {
     pub fn get_available_platform_profiles() -> Vec<String> {
         let path = "/sys/firmware/acpi/platform_profile_choices";
 
-        let Ok(content) = fs::read_to_string(path) else {
+        let Some(Ok(content)) = fs::read(path) else {
             return Vec::new();
         };
 
@@ -245,7 +236,7 @@ impl PowerSupply {
             );
         }
 
-        write("/sys/firmware/acpi/platform_profile", profile)
+        fs::write("/sys/firmware/acpi/platform_profile", profile)
             .context("this probably means that your system does not support changing ACPI profiles")
     }
 }

src/system.rs

@@ -0,0 +1,14 @@
+pub struct System {
+    pub is_desktop: bool,
+}
+
+impl System {
+    pub fn new() -> anyhow::Result<Self> {
+        let mut system = Self { is_desktop: false };
+        system.rescan()?;
+
+        Ok(system)
+    }
+
+    pub fn rescan(&mut self) -> anyhow::Result<()> {}
+}