librc: make rc_proc_getent available for all operating systems

This looks up an option on the kernel command line. For now, itworks on
linux and returns NULL on the bsds, but we are definitely open to
patches for that side.

src/librc/librc-misc.c

@@ -128,10 +128,10 @@ rc_getline(char **line, size_t *len, FILE *fp)
 }
 librc_hidden_def(rc_getline)
 
-#ifdef __linux__
 char *
 rc_proc_getent(const char *ent)
 {
+#ifdef __linux__
 	FILE *fp;
 	char *proc, *p, *value = NULL;
 	size_t i, len;
@@ -171,9 +171,11 @@ rc_proc_getent(const char *ent)
 	free(proc);
 
 	return value;
+#else
+	return NULL;
+#endif
 }
 librc_hidden_def(rc_proc_getent)
-#endif
 
 RC_STRINGLIST *
 rc_config_list(const char *file)

src/librc/librc.h

@@ -87,9 +87,7 @@ librc_hidden_proto(rc_find_pids)
 librc_hidden_proto(rc_getfile)
 librc_hidden_proto(rc_getline)
 librc_hidden_proto(rc_newer_than)
-#ifdef __linux__
 librc_hidden_proto(rc_proc_getent)
-#endif
 librc_hidden_proto(rc_older_than)
 librc_hidden_proto(rc_runlevel_exists)
 librc_hidden_proto(rc_runlevel_get)

src/librc/rc.h.in

@@ -360,12 +360,10 @@ bool rc_newer_than(const char *, const char *, time_t *, char *);
  * @return true if source is older than target, otherwise false */
 bool rc_older_than(const char *, const char *, time_t *, char *);
 
-#ifdef __linux__
 /*! Read variables/values from /proc/cmdline
  * @param value
  * @return pointer to the value, otherwise NULL */
 char *rc_proc_getent(const char *);
-#endif
 
 /*! Update the cached dependency tree if it's older than any init script,
  * its configuration file or an external configuration file the init script