moby/pkg/system/meminfo_linux.go
Daniel Nephin 4f0d95fa6e Add canonical import comment
Signed-off-by: Daniel Nephin <dnephin@docker.com>
2018-02-05 16:51:57 -05:00

65 lines
1.4 KiB
Go

package system // import "github.com/docker/docker/pkg/system"
import (
"bufio"
"io"
"os"
"strconv"
"strings"
"github.com/docker/go-units"
)
// ReadMemInfo retrieves memory statistics of the host system and returns a
// MemInfo type.
func ReadMemInfo() (*MemInfo, error) {
file, err := os.Open("/proc/meminfo")
if err != nil {
return nil, err
}
defer file.Close()
return parseMemInfo(file)
}
// parseMemInfo parses the /proc/meminfo file into
// a MemInfo object given an io.Reader to the file.
// Throws error if there are problems reading from the file
func parseMemInfo(reader io.Reader) (*MemInfo, error) {
meminfo := &MemInfo{}
scanner := bufio.NewScanner(reader)
for scanner.Scan() {
// Expected format: ["MemTotal:", "1234", "kB"]
parts := strings.Fields(scanner.Text())
// Sanity checks: Skip malformed entries.
if len(parts) < 3 || parts[2] != "kB" {
continue
}
// Convert to bytes.
size, err := strconv.Atoi(parts[1])
if err != nil {
continue
}
bytes := int64(size) * units.KiB
switch parts[0] {
case "MemTotal:":
meminfo.MemTotal = bytes
case "MemFree:":
meminfo.MemFree = bytes
case "SwapTotal:":
meminfo.SwapTotal = bytes
case "SwapFree:":
meminfo.SwapFree = bytes
}
}
// Handle errors that may have occurred during the reading of the file.
if err := scanner.Err(); err != nil {
return nil, err
}
return meminfo, nil
}