Split the part which actually refreshes the BlockDriverState.filename
field off of bdrv_refresh_filename() into a more generic function
bdrv_filename(), which first calls bdrv_refresh_filename() and then
stores a qemu-usable filename into the given buffer instead of
BlockDriverState.filename.
Since bdrv_refresh_filename() therefore no longer refreshes that field,
some calls to that function have to be replaced by calls to
bdrv_filename() "manually" refreshing the BDS filename field (this is
only temporary).
Additionally, a wrapper function bdrv_filename_alloc() is added which
allocates a buffer of size PATH_MAX, call bdrv_filename() on that buffer
and returns it, since needing a temporary buffer for the filename is a
rather common pattern.
Signed-off-by: Max Reitz <mre...@redhat.com>
---
block.c | 39 ++++++++++++++++++++++++++++++++-------
block/blkverify.c | 3 ++-
block/quorum.c | 2 +-
include/block/block.h | 2 ++
4 files changed, 37 insertions(+), 9 deletions(-)
diff --git a/block.c b/block.c
index 1572785..d2a3e8d 100644
--- a/block.c
+++ b/block.c
@@ -1559,7 +1559,7 @@ static int bdrv_open_inherit(BlockDriverState **pbs,
const char *filename,
}
}
- bdrv_refresh_filename(bs);
+ bdrv_filename(bs, bs->filename, sizeof(bs->filename));
/* For snapshot=on, create a temporary qcow2 overlay. bs points to the
* temporary snapshot afterwards. */
@@ -4153,9 +4153,6 @@ static bool append_open_options(QDict *d,
BlockDriverState *bs)
* - full_open_options: Options which, when given when opening a block device
* (without a filename), result in a BDS (mostly)
* equalling the given one
- * - filename: If exact_filename is set, it is copied here. Otherwise,
- * full_open_options is converted to a JSON object, prefixed with
- * "json:" (for use through the JSON pseudo protocol) and put
here.
*/
void bdrv_refresh_filename(BlockDriverState *bs)
{
@@ -4242,15 +4239,43 @@ void bdrv_refresh_filename(BlockDriverState *bs)
bs->full_open_options = opts;
}
+}
+
+/* First refreshes exact_filename and full_open_options by calling
+ * bdrv_refresh_filename(). Then, if exact_filename is set, it is copied into
+ * the target buffer. Otherwise, full_open_options is converted to a JSON
+ * object, prefixed with "json:" (for use through the JSON pseudo protocol) and
+ * put there.
+ *
+ * If sz > 0, the string put into the buffer will always be null-terminated.
+ *
+ * Returns @dest.
+ */
+char *bdrv_filename(BlockDriverState *bs, char *dest, size_t sz)
+{
+ bdrv_refresh_filename(bs);
+
+ if (sz > INT_MAX) {
+ sz = INT_MAX;
+ }
if (bs->exact_filename[0]) {
- pstrcpy(bs->filename, sizeof(bs->filename), bs->exact_filename);
+ pstrcpy(dest, sz, bs->exact_filename);
} else if (bs->full_open_options) {
QString *json = qobject_to_json(QOBJECT(bs->full_open_options));
- snprintf(bs->filename, sizeof(bs->filename), "json:%s",
- qstring_get_str(json));
+ snprintf(dest, sz, "json:%s", qstring_get_str(json));
QDECREF(json);
}
+
+ return dest;
+}
+
+/* Wrapper around bdrv_filename() using g_malloc(PATH_MAX) for the destination
+ * buffer.
+ */
+char *bdrv_filename_alloc(BlockDriverState *bs)
+{
+ return bdrv_filename(bs, g_malloc(PATH_MAX), PATH_MAX);
}
/* This accessor function purpose is to allow the device models to access the
diff --git a/block/blkverify.c b/block/blkverify.c
index d277e63..cb9ce02 100644
--- a/block/blkverify.c
+++ b/block/blkverify.c
@@ -309,7 +309,8 @@ static void blkverify_refresh_filename(BlockDriverState *bs)
BDRVBlkverifyState *s = bs->opaque;
/* bs->file has already been refreshed */
- bdrv_refresh_filename(s->test_file);
+ bdrv_filename(s->test_file, s->test_file->filename,
+ sizeof(s->test_file->filename));
if (bs->file->full_open_options && s->test_file->full_open_options) {
QDict *opts = qdict_new();
diff --git a/block/quorum.c b/block/quorum.c
index 2f6c45f..00d1fb0 100644
--- a/block/quorum.c
+++ b/block/quorum.c
@@ -1003,7 +1003,7 @@ static void quorum_refresh_filename(BlockDriverState *bs)
int i;
for (i = 0; i < s->num_children; i++) {
- bdrv_refresh_filename(s->bs[i]);
+ bdrv_filename(s->bs[i], s->bs[i]->filename,
sizeof(s->bs[i]->filename));
if (!s->bs[i]->full_open_options) {
return;
}
diff --git a/include/block/block.h b/include/block/block.h
index a78e4f1..4be6c18 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -267,6 +267,8 @@ BlockDriverState *bdrv_find_backing_image(BlockDriverState
*bs,
const char *backing_file);
int bdrv_get_backing_file_depth(BlockDriverState *bs);
void bdrv_refresh_filename(BlockDriverState *bs);
+char *bdrv_filename(BlockDriverState *bs, char *dest, size_t sz);
+char *bdrv_filename_alloc(BlockDriverState *bs);
int bdrv_truncate(BlockDriverState *bs, int64_t offset);
int64_t bdrv_nb_sectors(BlockDriverState *bs);
int64_t bdrv_getlength(BlockDriverState *bs);
--
2.4.3
