svn commit: r337952 - head/sys/kern

[Kyle Evans]

Author: kevans
Date: Fri Aug 17 03:42:57 2018
New Revision: 337952
URL: https://svnweb.freebsd.org/changeset/base/337952

Log:
  subr_prf: Don't write kern.boot_tag if it's empty
  
  This change allows one to set kern.boot_tag="" and not get a blank line
  preceding other boot messages. While this isn't super critical- blank lines
  are easy to filter out both mentally and in processing dmesg later- it
  allows for a mode of operation that matches previous behavior.
  
  I intend to MFC this whole series to stable/11 by the end of the month with
  boot_tag empty by default to make this effectively a nop in the stable
  branch.

Modified:
  head/sys/kern/subr_prf.c

Modified: head/sys/kern/subr_prf.c
==============================================================================
--- head/sys/kern/subr_prf.c	Fri Aug 17 03:05:09 2018	(r337951)
+++ head/sys/kern/subr_prf.c	Fri Aug 17 03:42:57 2018	(r337952)
@@ -1048,7 +1048,7 @@ msgbufinit(void *ptr, int size)
 	if (msgbufmapped && oldp != msgbufp)
 		msgbuf_copy(oldp, msgbufp);
 	msgbufmapped = true;
-	if (print_boot_tag)
+	if (print_boot_tag && *current_boot_tag != '\0')
 		printf("%s\n", current_boot_tag);
 	oldp = msgbufp;
 }