Linux support

internal/procstatm/procstatm.go

@@ -0,0 +1,37 @@
+package procstatm
+
+import (
+	"fmt"
+	"os"
+)
+
+// Statm provides statistics of memory.
+type Statm struct {
+	Size     uint
+	Resident uint
+	Share    uint
+	Text     uint
+	Lib      uint
+	Data     uint
+	Darty    uint
+}
+
+var zero = Statm{}
+
+// Get gets Statm for process (pid).
+// pid should be process id (integer) or string ("self" or so).
+func Get(pid interface{}) (Statm, error) {
+	name := fmt.Sprintf("/proc/%s/statm", pid)
+	f, err := os.Open(name)
+	if err != nil {
+		return zero, err
+	}
+	defer f.Close()
+	m := Statm{}
+	_, err = fmt.Fscanf(f, "%d %d %d %d %d %d %d",
+		&m.Size, &m.Resident, &m.Share, &m.Text, &m.Lib, &m.Data, &m.Darty)
+	if err != nil {
+		return zero, fmt.Errorf("failed to scan %s: %w", name, err)
+	}
+	return m, nil
+}

phymem.go

@@ -1,4 +1,5 @@
 // +build !windows
+// +build !linux
 
 package phymem
 

phymem_linux.go

@@ -0,0 +1,15 @@
+package phymem
+
+import "github.com/koron-go/phymem/internal/procstatm"
+
+// for test.
+const providedCurrent = true
+
+// Current get physical memory which used by current process.
+func Current() (uint, error) {
+	m, err := procstatm.Get("self")
+	if err != nil {
+		return 0, err
+	}
+	return m.Resident * 4096, nil
+}