Signed-off-by: Devin Nakamura <devin...@gmail.com>
---
block.c | 41 +++++++++++++++++++++++++++++++++++++++++
block.h | 2 ++
2 files changed, 43 insertions(+), 0 deletions(-)
diff --git a/block.c b/block.c
index aff1d34..76bd2e9 100644
--- a/block.c
+++ b/block.c
@@ -3349,3 +3349,44 @@ int bdrv_map(BlockDriverState *bs, uint64_t guest_offset,
return drv->bdrv_map(bs, guest_offset, host_offset,
contiguous_bytes);
}
+
+/**
+ * Copies out the header of a conversion target
+ *
+ * Saves the current header for the image in a temporary file and overwrites
+ * it with the header for the new format (at the moment the header is
+ * assumed to be 1 sector)
+ *
+ * A filename can be specified by using filename. On entry if
+ * filename = NULL , or filename points to an empty string, a random file
+ * name will be generated.
+ *
+ * If a random filename was generated it will be returned to the user by
+ * copying it to the location pointed at by filename. Filename must already
+ * be allocated to a size of at least PATH_MAX
+ *
+ * @param bs Usualy opened with bdrv_open_conversion_target()
+ * @param filename[in,out] On entry is the optional filename to be used. On
+ * exit it will be the filename used (assuming
+ * filename != NULL at entry)
+ * @return Returns non-zero on failure
+ */
+int bdrv_copy_header(BlockDriverState *bs, char *filename)
+{
+ BlockDriver *drv = bs->drv;
+ char tmp_filename[PATH_MAX] = "";
+
+ if (!drv) {
+ return -ENOMEDIUM;
+ }
+ if (!drv->bdrv_copy_header) {
+ return -ENOTSUP;
+ }
+ if (!filename) {
+ filename = tmp_filename;
+ }
+ if (!filename[0]) {
+ get_tmp_filename(filename, PATH_MAX);
+ }
+ return drv->bdrv_copy_header(bs, filename);
+}
diff --git a/block.h b/block.h
index 558b9b8..2fc546a 100644
--- a/block.h
+++ b/block.h
@@ -268,6 +268,8 @@ int bdrv_get_mapping(BlockDriverState *bs, uint64_t
guest_offset,
uint64_t *host_offset, uint64_t *contiguous_bytes);
int bdrv_map(BlockDriverState *bs, uint64_t guest_offset,
uint64_t host_offset, uint64_t contiguous_bytes);
+int bdrv_copy_header(BlockDriverState *bs, char *filename);
+
typedef enum {
BLKDBG_L1_UPDATE,
--
1.7.6.rc1
