libgo/go/os/user/getgrouplist_unix.go

   1 // Copyright 2016 The Go Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style
   3 // license that can be found in the LICENSE file.
   4
   5 //go:build (dragonfly || freebsd || hurd || (!android && linux) || netbsd || openbsd || (solaris && !illumos)) && cgo && !osusergo
   6
   7 package user
   8
   9 import (
  10         "fmt"
  11         "syscall"
  12 )
  13
  14 //extern-sysinfo getgrouplist
  15 func getGroupList(name *byte, userGID syscall.Gid_t, gids *syscall.Gid_t, n *int32) int32
  16
  17 // groupRetry retries getGroupList with much larger size for n. The result is
  18 // stored in gids.
  19 func groupRetry(username string, name []byte, userGID syscall.Gid_t, gids *[]syscall.Gid_t, n *int32) error {
  20         // More than initial buffer, but now n contains the correct size.
  21         if *n > maxGroups {
  22                 return fmt.Errorf("user: %q is a member of more than %d groups", username, maxGroups)
  23         }
  24         *gids = make([]syscall.Gid_t, *n)
  25         rv := getGroupList(&name[0], userGID, &(*gids)[0], n)
  26         if rv == -1 {
  27                 return fmt.Errorf("user: list groups for %s failed", username)
  28         }
  29         return nil
  30 }