Add support for FreeBSD.

This implementation requires to mount the Linux compatibility /proc
filesystem in /compat/linux/proc. Check the FreeBSD handbook for
details.

sigar_freebsd.go

@@ -0,0 +1,133 @@
+// Copied and modified from sigar_linux.go.
+
+package gosigar
+
+import (
+ "bufio"
+ "bytes"
+ "io"
+ "io/ioutil"
+ "strconv"
+ "strings"
+ "unsafe"
+)
+
+/*
+#include <sys/param.h>
+#include <sys/mount.h>
+#include <sys/ucred.h>
+#include <sys/types.h>
+#include <sys/sysctl.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <time.h>
+*/
+import "C"
+
+func init() {
+ system.ticks = uint64(C.sysconf(C._SC_CLK_TCK))
+
+ Procd = "/compat/linux/proc"
+
+ getLinuxBootTime()
+}
+
+func getMountTableFileName() string {
+ return Procd + "/mtab"
+}
+
+func (self *Uptime) Get() error {
+ ts := C.struct_timespec{}
+
+ if _, err := C.clock_gettime(C.CLOCK_UPTIME, &ts); err != nil {
+ return err
+ }
+
+ self.Length = float64(ts.tv_sec) + 1e-9*float64(ts.tv_nsec)
+
+ return nil
+}
+
+func (self *FDUsage) Get() error {
+ val := C.uint32_t(0)
+ sc := C.size_t(4)
+
+ name := C.CString("kern.openfiles")
+ _, err := C.sysctlbyname(name, unsafe.Pointer(&val), &sc, nil, 0)
+ C.free(unsafe.Pointer(name))
+ if err != nil {
+ return err
+ }
+ self.Open = uint64(val)
+
+ name = C.CString("kern.maxfiles")
+ _, err = C.sysctlbyname(name, unsafe.Pointer(&val), &sc, nil, 0)
+ C.free(unsafe.Pointer(name))
+ if err != nil {
+ return err
+ }
+ self.Max = uint64(val)
+
+ self.Unused = self.Max - self.Open
+
+ return nil
+}
+
+func (self *ProcFDUsage) Get(pid int) error {
+ err := readFile(procFileNameNative(pid, "rlimit"), func(line string) bool {
+ if strings.HasPrefix(line, "nofile ") {
+ fields := strings.Fields(line)
+ if len(fields) == 3 {
+ self.SoftLimit, _ = strconv.ParseUint(fields[1], 10, 64)
+ self.HardLimit, _ = strconv.ParseUint(fields[2], 10, 64)
+ }
+ return false
+ }
+ return true
+ })
+ if err != nil {
+ return err
+ }
+ fds, err := ioutil.ReadDir(procFileName(pid, "fd"))
+ if err != nil {
+ return err
+ }
+ self.Open = uint64(len(fds))
+ return nil
+}
+
+func parseCpuStat(self *Cpu, line string) error {
+ fields := strings.Fields(line)
+
+ self.User, _ = strtoull(fields[1])
+ self.Nice, _ = strtoull(fields[2])
+ self.Sys, _ = strtoull(fields[3])
+ self.Idle, _ = strtoull(fields[4])
+ return nil
+}
+
+func readFile(file string, handler func(string) bool) error {
+ contents, err := ioutil.ReadFile(file)
+ if err != nil {
+ return err
+ }
+
+ reader := bufio.NewReader(bytes.NewBuffer(contents))
+
+ for {
+ line, _, err := reader.ReadLine()
+ if err == io.EOF {
+ break
+ }
+ if !handler(string(line)) {
+ break
+ }
+ }
+
+ return nil
+}
+
+func procFileNameNative(pid int, name string) string {
+ return "/proc/" + strconv.Itoa(pid) + "/" + name
+}