Shuffle GPT_read() code into a nice switch{}, eliminating

unnecesary read of primary GPT when only the secondary GPT
is requested.

No intentional functional change.

diff --git a/sbin/fdisk/gpt.c b/sbin/fdisk/gpt.c
index 113ec56..e145bb0 100644 (file)
--- a/sbin/fdisk/gpt.c
+++ b/sbin/fdisk/gpt.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: gpt.c,v 1.14 2021/05/10 17:16:01 krw Exp $    */
+/*     $OpenBSD: gpt.c,v 1.15 2021/05/15 00:01:21 krw Exp $    */
 /*
  * Copyright (c) 2015 Markus Muller <mmu@grummel.net>
  * Copyright (c) 2015 Kenneth R Westerback <krw@openbsd.org>
@@ -196,25 +196,30 @@ GPT_read(int which)
 {
        int valid;
 
-       valid = GPT_get_header(GPTSECTOR);
-       if (valid == 0)
-               valid = GPT_get_partition_table(gh.gh_part_lba);
-       if (which == PRIMARYGPT || (which == ANYGPT && valid == 0))
+       switch (which) {
+       case PRIMARYGPT:
+               valid = GPT_get_header(GPTSECTOR);
+               break;
+       case SECONDARYGPT:
+               valid = GPT_get_header(DL_GETDSIZE(&dl) - 1);
+               break;
+       case ANYGPT:
+               valid = GPT_get_header(GPTSECTOR);
+               if (valid != 0 || GPT_get_partition_table(gh.gh_part_lba) != 0)
+                       valid = GPT_get_header(DL_GETDSIZE(&dl) - 1);
+               break;
+       default:
                return;
+       }
 
-       /* No valid GPT found. Zap any artifacts. */
-       memset(&gh, 0, sizeof(gh));
-       memset(&gp, 0, sizeof(gp));
-
-       valid = GPT_get_header(DL_GETDSIZE(&dl) - 1);
        if (valid == 0)
                valid = GPT_get_partition_table(gh.gh_part_lba);
-       if (which == SECONDARYGPT || valid == 0)
-               return;
 
-       /* No valid GPT found. Zap any artifacts. */
-       memset(&gh, 0, sizeof(gh));
-       memset(&gp, 0, sizeof(gp));
+       if (valid != 0) {
+               /* No valid GPT found. Zap any artifacts. */
+               memset(&gh, 0, sizeof(gh));
+               memset(&gp, 0, sizeof(gp));
+       }
 }
 
 void