1 files changed, 86 insertions, 18 deletions

diff --git a/vendor/github.com/tklauser/numcpus/numcpus_linux.go b/vendor/github.com/tklauser/numcpus/numcpus_linux.go
index 1a30525..7b991da 100644
--- a/vendor/github.com/tklauser/numcpus/numcpus_linux.go
+++ b/vendor/github.com/tklauser/numcpus/numcpus_linux.go
@@ -15,7 +15,7 @@
 package numcpus
 
 import (
-	"io/ioutil"
+	"fmt"
 	"os"
 	"path/filepath"
 	"strconv"
@@ -24,7 +24,14 @@ import (
 	"golang.org/x/sys/unix"
 )
 
-const sysfsCPUBasePath = "/sys/devices/system/cpu"
+const (
+	sysfsCPUBasePath = "/sys/devices/system/cpu"
+
+	offline  = "offline"
+	online   = "online"
+	possible = "possible"
+	present  = "present"
+)
 
 func getFromCPUAffinity() (int, error) {
 	var cpuSet unix.CPUSet
@@ -34,38 +41,83 @@ func getFromCPUAffinity() (int, error) {
 	return cpuSet.Count(), nil
 }
 
-func readCPURange(file string) (int, error) {
-	buf, err := ioutil.ReadFile(filepath.Join(sysfsCPUBasePath, file))
+func readCPURangeWith[T any](file string, f func(cpus string) (T, error)) (T, error) {
+	var zero T
+	buf, err := os.ReadFile(filepath.Join(sysfsCPUBasePath, file))
 	if err != nil {
-		return 0, err
+		return zero, err
 	}
-	return parseCPURange(strings.Trim(string(buf), "\n "))
+	return f(strings.Trim(string(buf), "\n "))
 }
 
-func parseCPURange(cpus string) (int, error) {
+func countCPURange(cpus string) (int, error) {
+	// Treat empty file as valid. This might be the case if there are no offline CPUs in which
+	// case /sys/devices/system/cpu/offline is empty.
+	if cpus == "" {
+		return 0, nil
+	}
+
 	n := int(0)
 	for _, cpuRange := range strings.Split(cpus, ",") {
-		if len(cpuRange) == 0 {
-			continue
+		if cpuRange == "" {
+			return 0, fmt.Errorf("empty CPU range in CPU string %q", cpus)
 		}
-		rangeOp := strings.SplitN(cpuRange, "-", 2)
-		first, err := strconv.ParseUint(rangeOp[0], 10, 32)
+		from, to, found := strings.Cut(cpuRange, "-")
+		first, err := strconv.ParseUint(from, 10, 32)
 		if err != nil {
 			return 0, err
 		}
-		if len(rangeOp) == 1 {
+		if !found {
 			n++
 			continue
 		}
-		last, err := strconv.ParseUint(rangeOp[1], 10, 32)
+		last, err := strconv.ParseUint(to, 10, 32)
 		if err != nil {
 			return 0, err
 		}
+		if last < first {
+			return 0, fmt.Errorf("last CPU in range (%d) less than first (%d)", last, first)
+		}
 		n += int(last - first + 1)
 	}
 	return n, nil
 }
 
+func listCPURange(cpus string) ([]int, error) {
+	// See comment in countCPURange.
+	if cpus == "" {
+		return []int{}, nil
+	}
+
+	list := []int{}
+	for _, cpuRange := range strings.Split(cpus, ",") {
+		if cpuRange == "" {
+			return nil, fmt.Errorf("empty CPU range in CPU string %q", cpus)
+		}
+		from, to, found := strings.Cut(cpuRange, "-")
+		first, err := strconv.ParseUint(from, 10, 32)
+		if err != nil {
+			return nil, err
+		}
+		if !found {
+			// range containing a single element
+			list = append(list, int(first))
+			continue
+		}
+		last, err := strconv.ParseUint(to, 10, 32)
+		if err != nil {
+			return nil, err
+		}
+		if last < first {
+			return nil, fmt.Errorf("last CPU in range (%d) less than first (%d)", last, first)
+		}
+		for cpu := int(first); cpu <= int(last); cpu++ {
+			list = append(list, cpu)
+		}
+	}
+	return list, nil
+}
+
 func getConfigured() (int, error) {
 	d, err := os.Open(sysfsCPUBasePath)
 	if err != nil {
@@ -89,7 +141,7 @@ func getConfigured() (int, error) {
 }
 
 func getKernelMax() (int, error) {
-	buf, err := ioutil.ReadFile(filepath.Join(sysfsCPUBasePath, "kernel_max"))
+	buf, err := os.ReadFile(filepath.Join(sysfsCPUBasePath, "kernel_max"))
 	if err != nil {
 		return 0, err
 	}
@@ -101,20 +153,36 @@ func getKernelMax() (int, error) {
 }
 
 func getOffline() (int, error) {
-	return readCPURange("offline")
+	return readCPURangeWith(offline, countCPURange)
 }
 
 func getOnline() (int, error) {
 	if n, err := getFromCPUAffinity(); err == nil {
 		return n, nil
 	}
-	return readCPURange("online")
+	return readCPURangeWith(online, countCPURange)
 }
 
 func getPossible() (int, error) {
-	return readCPURange("possible")
+	return readCPURangeWith(possible, countCPURange)
 }
 
 func getPresent() (int, error) {
-	return readCPURange("present")
+	return readCPURangeWith(present, countCPURange)
+}
+
+func listOffline() ([]int, error) {
+	return readCPURangeWith(offline, listCPURange)
+}
+
+func listOnline() ([]int, error) {
+	return readCPURangeWith(online, listCPURange)
+}
+
+func listPossible() ([]int, error) {
+	return readCPURangeWith(possible, listCPURange)
+}
+
+func listPresent() ([]int, error) {
+	return readCPURangeWith(present, listCPURange)
 }