[Qemu-devel] [PATCH 4/4] block/vdi: Improved return values from vdi_open and other small fixes

[Stefan Weil]

vdi_open returned -1 in case of any error, but it should return an
error code (negative value of errno or BDRV_WRONG_FORMAT).

vdi_open did not check for a bad signature. This check was only in vdi_probe.

The signature is a 32 bit value and needs up to 8 hex digits for printing.

Signed-off-by: Stefan Weil <address@hidden>
---
 block/vdi.c |   25 ++++++++++++++++++++-----
 1 file changed, 20 insertions(+), 5 deletions(-)

diff --git a/block/vdi.c b/block/vdi.c
index c8330b7..7c7699f 100644
--- a/block/vdi.c
+++ b/block/vdi.c
@@ -246,7 +246,7 @@ static void vdi_header_print(VdiHeader *header)
 {
     char uuid[37];
     logout("text        %s", header->text);
-    logout("signature   0x%04x\n", header->signature);
+    logout("signature   0x%08x\n", header->signature);
     logout("header size 0x%04x\n", header->header_size);
     logout("image type  0x%04x\n", header->image_type);
     logout("image flags 0x%04x\n", header->image_flags);
@@ -369,10 +369,12 @@ static int vdi_open(BlockDriverState *bs, int flags)
     BDRVVdiState *s = bs->opaque;
     VdiHeader header;
     size_t bmap_size;
+    int ret;
 
     logout("\n");
 
-    if (bdrv_read(bs->file, 0, (uint8_t *)&header, 1) < 0) {
+    ret = bdrv_read(bs->file, 0, (uint8_t *)&header, 1);
+    if (ret < 0) {
         goto fail;
     }
 
@@ -390,33 +392,45 @@ static int vdi_open(BlockDriverState *bs, int flags)
         header.disk_size &= ~(SECTOR_SIZE - 1);
     }
 
-    if (header.version != VDI_VERSION_1_1) {
+    if (header.signature != VDI_SIGNATURE) {
+        logout("bad vdi signature %08x\n", header.signature);
+        ret = BDRV_WRONG_FORMAT;
+        goto fail;
+    } else if (header.version != VDI_VERSION_1_1) {
         logout("unsupported version %u.%u\n",
                header.version >> 16, header.version & 0xffff);
+        ret = -ENOTSUP;
         goto fail;
     } else if (header.offset_bmap % SECTOR_SIZE != 0) {
         /* We only support block maps which start on a sector boundary. */
         logout("unsupported block map offset 0x%x B\n", header.offset_bmap);
+        ret = -ENOTSUP;
         goto fail;
     } else if (header.offset_data % SECTOR_SIZE != 0) {
         /* We only support data blocks which start on a sector boundary. */
         logout("unsupported data offset 0x%x B\n", header.offset_data);
+        ret = -ENOTSUP;
         goto fail;
     } else if (header.sector_size != SECTOR_SIZE) {
         logout("unsupported sector size %u B\n", header.sector_size);
+        ret = -ENOTSUP;
         goto fail;
     } else if (header.block_size != 1 * MiB) {
         logout("unsupported block size %u B\n", header.block_size);
+        ret = -ENOTSUP;
         goto fail;
     } else if (header.disk_size >
                (uint64_t)header.blocks_in_image * header.block_size) {
         logout("unsupported disk size %" PRIu64 " B\n", header.disk_size);
+        ret = -ENOTSUP;
         goto fail;
     } else if (!uuid_is_null(header.uuid_link)) {
         logout("link uuid != 0, unsupported\n");
+        ret = -ENOTSUP;
         goto fail;
     } else if (!uuid_is_null(header.uuid_parent)) {
         logout("parent uuid != 0, unsupported\n");
+        ret = -ENOTSUP;
         goto fail;
     }
 
@@ -432,7 +446,8 @@ static int vdi_open(BlockDriverState *bs, int flags)
     if (bmap_size > 0) {
         s->bmap = g_malloc(bmap_size * SECTOR_SIZE);
     }
-    if (bdrv_read(bs->file, s->bmap_sector, (uint8_t *)s->bmap, bmap_size) < 
0) {
+    ret = bdrv_read(bs->file, s->bmap_sector, (uint8_t *)s->bmap, bmap_size);
+    if (ret < 0) {
         goto fail_free_bmap;
     }
 
@@ -448,7 +463,7 @@ static int vdi_open(BlockDriverState *bs, int flags)
     g_free(s->bmap);
 
  fail:
-    return -1;
+    return ret;
 }
 
 static int vdi_reopen_prepare(BDRVReopenState *state,
-- 
1.7.10.4