From 1e297b34baab956c09003283b8b8b6900bd6cbdf Mon Sep 17 00:00:00 2001
From: Tomohiro Kusumi <kusumi.tomohiro@gmail.com>
Date: Thu, 3 Nov 2016 23:37:09 +0900
Subject: [PATCH] sbin/mount_hammer: Fix/cleanup test_volumes()

The requirement of this function is basically the same as
__verify_volume() in sbin/hammer/ondisk.c, so make it
__verify_volume() based.

Note that this function doesn't necessarily print the real
reason mount(2) failed, as shown in a comment. This function
just takes a wild guess with sanity checks on volume header.
The real reason is likely to be in dmesg. This originally
didn't exist, but was added by 1a607e3e in 2009.
---
 sbin/mount_hammer/mount_hammer.c | 48 ++++++++++++++++++++++++++--------------
 1 file changed, 32 insertions(+), 16 deletions(-)

diff --git a/sbin/mount_hammer/mount_hammer.c b/sbin/mount_hammer/mount_hammer.c
index fb39474720..ea17b64fce 100644
--- a/sbin/mount_hammer/mount_hammer.c
+++ b/sbin/mount_hammer/mount_hammer.c
@@ -240,17 +240,44 @@ free_volumes(struct hammer_mount_info *info)
 	free(info->volumes);
 }
 
+/*
+ * This function is based on __verify_volume() in sbin/hammer/ondisk.c.
+ */
+static
+void
+__verify_volume(hammer_volume_ondisk_t ondisk,
+	const char *vol_name, int vol_count)
+{
+	if (ondisk->vol_signature != HAMMER_FSBUF_VOLUME) {
+		errx(1, "%s: Invalid volume signature %016jx",
+			vol_name, ondisk->vol_signature);
+	}
+	if (ondisk->vol_count != vol_count) {
+		errx(1, "%s: Invalid volume count %d, "
+			"volume header says %d volumes",
+			vol_name, vol_count, ondisk->vol_count);
+	}
+	if (ondisk->vol_rootvol != HAMMER_ROOT_VOLNO) {
+		errx(1, "%s: Invalid root volume# %d",
+			vol_name, ondisk->vol_rootvol);
+	}
+}
+
+/*
+ * This function prints a possible reason that mount(2) failed,
+ * which isn't really necessary as the real reason is likely to
+ * be in dmesg anyway, but was originally added by 1a607e3e.
+ */
 static
 void
 test_volumes(struct hammer_mount_info *info)
 {
 	int i, fd;
-	const char *vol;
 	char buf[2048]; /* sizeof(*ondisk) is 1928 */
 	hammer_volume_ondisk_t ondisk = (hammer_volume_ondisk_t)buf;
 
 	for (i = 0; i < info->nvolumes; i++) {
-		vol = info->volumes[i];
+		const char *vol = info->volumes[i];
 		fd = open(vol, O_RDONLY);
 		if (fd < 0) {
 			fprintf(stderr, "%s: Failed to open\n", vol);
@@ -259,23 +286,12 @@ test_volumes(struct hammer_mount_info *info)
 
 		bzero(buf, sizeof(buf));
 		if (pread(fd, buf, sizeof(buf), 0) != sizeof(buf)) {
-			fprintf(stderr,
-				"%s: Failed to read volume header\n", vol);
+			fprintf(stderr, "%s: Failed to read volume header\n",
+				vol);
 			goto next;
 		}
 
-		if (ondisk->vol_signature != HAMMER_FSBUF_VOLUME) {
-			fprintf(stderr,
-				"%s: Invalid volume signature %016jx\n",
-				vol, ondisk->vol_signature);
-			goto next;
-		}
-		if (ondisk->vol_count != info->nvolumes) {
-			fprintf(stderr,
-				"%s: Volume header says %d volumes\n",
-				vol, ondisk->vol_count);
-			goto next;
-		}
+		__verify_volume(ondisk, vol, info->nvolumes);
 next:
 		close(fd);
 	}
-- 
2.11.4.GIT