platform: Improve OOM killer for iOS

service/oomkiller/config.go

@@ -0,0 +1,51 @@
+package oomkiller
+
+import (
+	"time"
+
+	"github.com/sagernet/sing-box/option"
+	E "github.com/sagernet/sing/common/exceptions"
+)
+
+func buildTimerConfig(options option.OOMKillerServiceOptions, memoryLimit uint64, useAvailable bool) (timerConfig, error) {
+	safetyMargin := uint64(defaultSafetyMargin)
+	if options.SafetyMargin != nil && options.SafetyMargin.Value() > 0 {
+		safetyMargin = options.SafetyMargin.Value()
+	}
+
+	minInterval := defaultMinInterval
+	if options.MinInterval != 0 {
+		minInterval = time.Duration(options.MinInterval.Build())
+		if minInterval <= 0 {
+			return timerConfig{}, E.New("min_interval must be greater than 0")
+		}
+	}
+
+	maxInterval := defaultMaxInterval
+	if options.MaxInterval != 0 {
+		maxInterval = time.Duration(options.MaxInterval.Build())
+		if maxInterval <= 0 {
+			return timerConfig{}, E.New("max_interval must be greater than 0")
+		}
+	}
+	if maxInterval < minInterval {
+		return timerConfig{}, E.New("max_interval must be greater than or equal to min_interval")
+	}
+
+	checksBeforeLimit := defaultChecksBeforeLimit
+	if options.ChecksBeforeLimit != 0 {
+		checksBeforeLimit = options.ChecksBeforeLimit
+		if checksBeforeLimit <= 0 {
+			return timerConfig{}, E.New("checks_before_limit must be greater than 0")
+		}
+	}
+
+	return timerConfig{
+		memoryLimit:       memoryLimit,
+		safetyMargin:      safetyMargin,
+		minInterval:       minInterval,
+		maxInterval:       maxInterval,
+		checksBeforeLimit: checksBeforeLimit,
+		useAvailable:      useAvailable,
+	}, nil
+}