Re: [PATCH] btrfs-progs: print-tree: fix chunk/block group flags output

On Tue, Oct 12, 2021 at 10:17:19AM +0800, Qu Wenruo wrote:

[BUG]
Commit ("btrfs-progs: use raid table for profile names in
print-tree.c") introduced one bug in block group and chunk flags output
and changed the behavior:

	item 1 key (FIRST_CHUNK_TREE CHUNK_ITEM 13631488) itemoff 16105 itemsize 80
		length 8388608 owner 2 stripe_len 65536 type SINGLE
		...
	item 2 key (FIRST_CHUNK_TREE CHUNK_ITEM 22020096) itemoff 15993 itemsize 112
		length 8388608 owner 2 stripe_len 65536 type DUP
		...
	item 3 key (FIRST_CHUNK_TREE CHUNK_ITEM 30408704) itemoff 15881 itemsize 112
		length 268435456 owner 2 stripe_len 65536 type DUP
		...

Note that, the flag string only contains the profile (SINGLE/DUP/etc...)
no type (DATA/METADATA/SYSTEM).

And we have new "SINGLE" string, even that profile has no extra bit to
indicate that.

[CAUSE]
The "SINGLE" part is caused by the raid array which has a name for
SINGLE profile, even it doesn't have corresponding bit.

The missing type string is caused by a code bug:

		strcpy(buf, name);
		while (*tmp) {
			*tmp = toupper(*tmp);
			tmp++;
		}
		strcpy(ret, buf);

The last strcpy() call overrides the existing string in @ret.

[FIX]
- Enhance string handling using strn*()/snprintf()

- Add extra "UKNOWN.0x%llx" output for unknown profiles

- Call proper strncat() to merge type and profile

- Add extra handling for "SINGLE" to keep the old output

Signed-off-by: Qu Wenruo <redacted>

Added to devel, thanks.