src/systemctl/systemctl-whoami.c

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2
   3 #include "format-util.h"
   4 #include "parse-util.h"
   5 #include "systemctl.h"
   6 #include "systemctl-util.h"
   7 #include "systemctl-whoami.h"
   8
   9 int verb_whoami(int argc, char *argv[], void *userdata) {
  10         sd_bus *bus;
  11         int r, ret = 0;
  12
  13         r = acquire_bus(BUS_FULL, &bus);
  14         if (r < 0)
  15                 return r;
  16
  17         if (argc <= 1) {
  18                 _cleanup_free_ char *unit = NULL;
  19
  20                 if (arg_transport != BUS_TRANSPORT_LOCAL)
  21                         return log_error_errno(SYNTHETIC_ERRNO(EREMOTE),
  22                                                "Refusing to look up our local PID on remote host.");
  23
  24                 /* Our own process can never go away while querying, hence no need to go through pidfd. */
  25
  26                 r = get_unit_by_pid(bus, 0, &unit, /* ret_path = */ NULL);
  27                 if (r < 0)
  28                         return r;
  29
  30                 puts(unit);
  31                 return 0;
  32         }
  33
  34         STRV_FOREACH(pidstr, strv_skip(argv, 1)) {
  35                 _cleanup_free_ char *unit = NULL;
  36                 pid_t pid;
  37
  38                 r = parse_pid(*pidstr, &pid);
  39                 if (r < 0)
  40                         return log_error_errno(r, "Invalid PID specified: %s", *pidstr);
  41
  42                 r = lookup_unit_by_pidref(bus, pid, &unit, /* ret_path = */ NULL);
  43                 if (r < 0)
  44                         RET_GATHER(ret, r);
  45                 else
  46                         puts(unit);
  47         }
  48
  49         return ret;
  50 }