update user config to allow for nil sshcfg while also simplifying

the code would previously get the current user (current execution's context)
whereas the cfg.User value already takes the ConnectionURI's set username which
should be sufficient as a default value check.

libvirt/uri/ssh.go

@@ -5,7 +5,6 @@ import (
  "log"
  "net"
  "os"
- "os/user"
  "path/filepath"
  "strings"
 
@@ -275,20 +274,16 @@ func (u *ConnectionURI) dialHost(target string, sshcfg *ssh_config.Config, depth
  }
  }
 
- if cfg.User == "" {
+ // cfg.User value defaults to u.User.Username()
+ if sshcfg != nil {
  sshu, err := sshcfg.Get(target, "User")
- log.Printf("[DEBUG] SSH User for target '%v' is '%v'", target, sshu)
  if err != nil {
- log.Printf("[DEBUG] ssh user: using current login")
- u, err := user.Current()
- if err != nil {
- return nil, fmt.Errorf("unable to get username: %w", err)
- }
- sshu = u.Username
+ log.Printf("[DEBUG] ssh user for target '%v' is overriden to '%v'", target, sshu)
+ cfg.User = sshu
  }
- cfg.User = sshu
  }
 
+
  cfg.Auth = u.parseAuthMethods(target, sshcfg)
  if len(cfg.Auth) < 1 {
  return nil, fmt.Errorf("could not configure SSH authentication methods")