exit-status: remove ExitStatus typedef

Do not make up our own type for ExitStatus, but use the type used by POSIX for
this, which is "int".  In particular as we never used that type outside of the
definition of exit_status_to_string() where we internally cast the paramter to
(int) every single time we used it.

Hence, let's simplify things, drop the type and use the kernel type directly.

src/basic/exit-status.c

@@ -24,12 +24,12 @@
 #include "macro.h"
 #include "set.h"
 
-const char* exit_status_to_string(ExitStatus status, ExitStatusLevel level) {
+const char* exit_status_to_string(int status, ExitStatusLevel level) {
 
         /* We cast to int here, so that -Wenum doesn't complain that
          * EXIT_SUCCESS/EXIT_FAILURE aren't in the enum */
 
-        switch ((int) status) {
+        switch (status) {
 
         case EXIT_SUCCESS:
                 return "SUCCESS";
@@ -39,7 +39,7 @@ const char* exit_status_to_string(ExitStatus status, ExitStatusLevel level) {
         }
 
         if (IN_SET(level, EXIT_STATUS_SYSTEMD, EXIT_STATUS_LSB)) {
-                switch ((int) status) {
+                switch (status) {
 
                 case EXIT_CHDIR:
                         return "CHDIR";
@@ -152,7 +152,7 @@ const char* exit_status_to_string(ExitStatus status, ExitStatusLevel level) {
         }
 
         if (level == EXIT_STATUS_LSB) {
-                switch ((int) status) {
+                switch (status) {
 
                 case EXIT_INVALIDARGUMENT:
                         return "INVALIDARGUMENT";
@@ -177,7 +177,6 @@ const char* exit_status_to_string(ExitStatus status, ExitStatusLevel level) {
         return NULL;
 }
 
-
 bool is_clean_exit(int code, int status, ExitStatusSet *success_status) {
 
         if (code == CLD_EXITED)

src/basic/exit-status.h

@@ -31,7 +31,7 @@
  * https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/iniscrptact.html
  */
 
-typedef enum ExitStatus {
+enum {
         /* EXIT_SUCCESS defined by libc */
         /* EXIT_FAILURE defined by libc */
         EXIT_INVALIDARGUMENT = 2,
@@ -82,7 +82,7 @@ typedef enum ExitStatus {
         EXIT_MAKE_STARTER,
         EXIT_CHOWN,
         EXIT_SMACK_PROCESS_LABEL,
-} ExitStatus;
+};
 
 typedef enum ExitStatusLevel {
         EXIT_STATUS_MINIMAL,   /* only cover libc EXIT_STATUS/EXIT_FAILURE */
@@ -96,7 +96,7 @@ typedef struct ExitStatusSet {
         Set *signal;
 } ExitStatusSet;
 
-const char* exit_status_to_string(ExitStatus status, ExitStatusLevel level) _const_;
+const char* exit_status_to_string(int status, ExitStatusLevel level) _const_;
 
 bool is_clean_exit(int code, int status, ExitStatusSet *success_status);
 bool is_clean_exit_lsb(int code, int status, ExitStatusSet *success_status);