func CountsWithContext()

in patches/gopsutil/v3/cpu/cpu_linux.go [309:400]

• 83 lines of code
• 29 McCabe index (conditional complexity)

func CountsWithContext(ctx context.Context, logical bool) (int, error) {
	if logical {
		ret := 0
		// https://github.com/giampaolo/psutil/blob/d01a9eaa35a8aadf6c519839e987a49d8be2d891/psutil/_pslinux.py#L599
		procCpuinfo := common.HostProc("cpuinfo")
		lines, err := common.ReadLines(procCpuinfo)
		if err == nil {
			for _, line := range lines {
				line = strings.ToLower(line)
				if strings.HasPrefix(line, "processor") {
					_, err = strconv.Atoi(strings.TrimSpace(line[strings.IndexByte(line, ':')+1:]))
					if err == nil {
						ret++
					}
				}
			}
		}
		if ret == 0 {
			procStat := common.HostProc("stat")
			lines, err = common.ReadLines(procStat)
			if err != nil {
				return 0, err
			}
			for _, line := range lines {
				if len(line) >= 4 && strings.HasPrefix(line, "cpu") && '0' <= line[3] && line[3] <= '9' { // `^cpu\d` regexp matching
					ret++
				}
			}
		}
		return ret, nil
	}
	// physical cores
	// https://github.com/giampaolo/psutil/blob/8415355c8badc9c94418b19bdf26e622f06f0cce/psutil/_pslinux.py#L615-L628
	threadSiblingsLists := make(map[string]bool)
	// These 2 files are the same but */core_cpus_list is newer while */thread_siblings_list is deprecated and may disappear in the future.
	// https://www.kernel.org/doc/Documentation/admin-guide/cputopology.rst
	// https://github.com/giampaolo/psutil/pull/1727#issuecomment-707624964
	// https://lkml.org/lkml/2019/2/26/41
	for _, glob := range []string{"devices/system/cpu/cpu[0-9]*/topology/core_cpus_list", "devices/system/cpu/cpu[0-9]*/topology/thread_siblings_list"} {
		if files, err := filepath.Glob(common.HostSys(glob)); err == nil {
			for _, file := range files {
				lines, err := common.ReadLines(file)
				if err != nil || len(lines) != 1 {
					continue
				}
				threadSiblingsLists[lines[0]] = true
			}
			ret := len(threadSiblingsLists)
			if ret != 0 {
				return ret, nil
			}
		}
	}
	// https://github.com/giampaolo/psutil/blob/122174a10b75c9beebe15f6c07dcf3afbe3b120d/psutil/_pslinux.py#L631-L652
	filename := common.HostProc("cpuinfo")
	lines, err := common.ReadLines(filename)
	if err != nil {
		return 0, err
	}
	mapping := make(map[int]int)
	currentInfo := make(map[string]int)
	for _, line := range lines {
		line = strings.ToLower(strings.TrimSpace(line))
		if line == "" {
			// new section
			id, okID := currentInfo["physical id"]
			cores, okCores := currentInfo["cpu cores"]
			if okID && okCores {
				mapping[id] = cores
			}
			currentInfo = make(map[string]int)
			continue
		}
		fields := strings.Split(line, ":")
		if len(fields) < 2 {
			continue
		}
		fields[0] = strings.TrimSpace(fields[0])
		if fields[0] == "physical id" || fields[0] == "cpu cores" {
			val, err := strconv.Atoi(strings.TrimSpace(fields[1]))
			if err != nil {
				continue
			}
			currentInfo[fields[0]] = val
		}
	}
	ret := 0
	for _, v := range mapping {
		ret += v
	}
	return ret, nil
}