Fix confusion between killer and prey

"who" is the entity doing the killing, "whom" is the target.
Follow-up for 4ccde410a3.

src/machine/machine-dbus.c

@@ -123,7 +123,7 @@ int bus_machine_method_kill(sd_bus_message *message, void *userdata, sd_bus_erro
         Machine *m = ASSERT_PTR(userdata);
         const char *swho;
         int32_t signo;
-        KillWho who;
+        KillWhom whom;
         int r;
 
         assert(message);
@@ -133,10 +133,10 @@ int bus_machine_method_kill(sd_bus_message *message, void *userdata, sd_bus_erro
                 return r;
 
         if (isempty(swho))
-                who = KILL_ALL;
+                whom = KILL_ALL;
         else {
-                who = kill_who_from_string(swho);
-                if (who < 0)
+                whom = kill_whom_from_string(swho);
+                if (whom < 0)
                         return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid kill parameter '%s'", swho);
         }
 
@@ -160,7 +160,7 @@ int bus_machine_method_kill(sd_bus_message *message, void *userdata, sd_bus_erro
         if (r == 0)
                 return 1; /* Will call us back */
 
-        r = machine_kill(m, who, signo);
+        r = machine_kill(m, whom, signo);
         if (r < 0)
                 return r;
 
@@ -1293,7 +1293,7 @@ static const sd_bus_vtable machine_vtable[] = {
                       bus_machine_method_terminate,
                       SD_BUS_VTABLE_UNPRIVILEGED),
         SD_BUS_METHOD_WITH_ARGS("Kill",
-                                SD_BUS_ARGS("s", who, "i", signal),
+                                SD_BUS_ARGS("s", whom, "i", signal),
                                 SD_BUS_NO_RESULT,
                                 bus_machine_method_kill,
                                 SD_BUS_VTABLE_UNPRIVILEGED),

src/machine/machine.c

@@ -609,7 +609,7 @@ MachineState machine_get_state(Machine *s) {
         return MACHINE_RUNNING;
 }
 
-int machine_kill(Machine *m, KillWho who, int signo) {
+int machine_kill(Machine *m, KillWhom whom, int signo) {
         assert(m);
 
         if (!IN_SET(m->class, MACHINE_VM, MACHINE_CONTAINER))
@@ -618,7 +618,7 @@ int machine_kill(Machine *m, KillWho who, int signo) {
         if (!m->unit)
                 return -ESRCH;
 
-        if (who == KILL_LEADER) /* If we shall simply kill the leader, do so directly */
+        if (whom == KILL_LEADER) /* If we shall simply kill the leader, do so directly */
                 return pidref_kill(&m->leader, signo);
 
         /* Otherwise, make PID 1 do it for us, for the entire cgroup */
@@ -920,9 +920,9 @@ static const char* const machine_state_table[_MACHINE_STATE_MAX] = {
 
 DEFINE_STRING_TABLE_LOOKUP(machine_state, MachineState);
 
-static const char* const kill_who_table[_KILL_WHO_MAX] = {
+static const char* const kill_whom_table[_KILL_WHOM_MAX] = {
         [KILL_LEADER] = "leader",
         [KILL_ALL] = "all"
 };
 
-DEFINE_STRING_TABLE_LOOKUP(kill_who, KillWho);
+DEFINE_STRING_TABLE_LOOKUP(kill_whom, KillWhom);

src/machine/machine.h

@@ -2,7 +2,7 @@
 #pragma once
 
 typedef struct Machine Machine;
-typedef enum KillWho KillWho;
+typedef enum KillWhom KillWhom;
 
 #include "list.h"
 #include "machined.h"
@@ -26,11 +26,11 @@ typedef enum MachineClass {
         _MACHINE_CLASS_INVALID = -EINVAL,
 } MachineClass;
 
-enum KillWho {
+enum KillWhom {
         KILL_LEADER,
         KILL_ALL,
-        _KILL_WHO_MAX,
-        _KILL_WHO_INVALID = -EINVAL,
+        _KILL_WHOM_MAX,
+        _KILL_WHOM_INVALID = -EINVAL,
 };
 
 struct Machine {
@@ -81,7 +81,7 @@ int machine_stop(Machine *m);
 int machine_finalize(Machine *m);
 int machine_save(Machine *m);
 int machine_load(Machine *m);
-int machine_kill(Machine *m, KillWho who, int signo);
+int machine_kill(Machine *m, KillWhom whom, int signo);
 
 DEFINE_TRIVIAL_CLEANUP_FUNC(Machine*, machine_free);
 
@@ -95,8 +95,8 @@ MachineClass machine_class_from_string(const char *s) _pure_;
 const char* machine_state_to_string(MachineState t) _const_;
 MachineState machine_state_from_string(const char *s) _pure_;
 
-const char *kill_who_to_string(KillWho k) _const_;
-KillWho kill_who_from_string(const char *s) _pure_;
+const char *kill_whom_to_string(KillWhom k) _const_;
+KillWhom kill_whom_from_string(const char *s) _pure_;
 
 int machine_openpt(Machine *m, int flags, char **ret_slave);
 int machine_open_terminal(Machine *m, const char *path, int mode);

src/machine/test-machine-tables.c

@@ -7,7 +7,7 @@
 int main(int argc, char **argv) {
         test_setup_logging(LOG_DEBUG);
 
-        test_table(kill_who, KILL_WHO);
+        test_table(kill_whom, KILL_WHOM);
         test_table(machine_class, MACHINE_CLASS);
         test_table(machine_state, MACHINE_STATE);