Fixed-size VHD images don't have a header, only a footer. To be able
to still detect them right, support probing via the file name, too.
Without this change, images get detected as raw:
$ qemu-img create -f vpc -o subformat=fixed test.vhd 2G
Formatting 'test.vhd', fmt=vpc size=2147483648 subformat=fixed
$ qemu-img info test.vhd
image: test.vhd
file format: raw
virtual size: 2 GiB (2147992064 bytes)
disk size: 8 KiB
With this change:
$ qemu-img info test.vhd
image: test.vhd
file format: vpc
virtual size: 2 GiB (2147991552 bytes)
disk size: 8 KiB
Resolves: https://bugs.launchpad.net/qemu/+bug/1819182
Signed-off-by: Thomas Huth <thuth@redhat.com>
---
I've marked the subject with RFC since I'm not quite sure whether this
is really a good idea... please let me know what you think about it...
block/vpc.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/block/vpc.c b/block/vpc.c
index 17a705b482..be561e4b39 100644
--- a/block/vpc.c
+++ b/block/vpc.c
@@ -191,8 +191,18 @@ static uint32_t vpc_checksum(void *p, size_t size)
static int vpc_probe(const uint8_t *buf, int buf_size, const char *filename)
{
- if (buf_size >= 8 && !strncmp((char *)buf, "conectix", 8))
+ if (buf_size >= 8 && !strncmp((char *)buf, "conectix", 8)) {
return 100;
+ }
+
+ /* It could be a fixed-size image without header -> check extension, too */
+ if (filename) {
+ int len = strlen(filename);
+ if (len > 4 && !strcasecmp(&filename[len - 4], ".vhd")) {
+ return 10;
+ }
+ }
+
return 0;
}