block: bdrv_get_full_backing_filename's ret. val.
Make bdrv_get_full_backing_filename() return an allocated string instead
of placing the result in a caller-provided buffer.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-id: 20190201192935.18394-12-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
diff --git a/block.c b/block.c
index 466d788..a2203f0 100644
--- a/block.c
+++ b/block.c
@@ -338,28 +338,16 @@
}
}
-void bdrv_get_full_backing_filename(BlockDriverState *bs, char *dest, size_t sz,
- Error **errp)
+char *bdrv_get_full_backing_filename(BlockDriverState *bs, Error **errp)
{
char *backed;
- char *full_name;
- Error *local_error = NULL;
bdrv_refresh_filename(bs);
backed = bs->exact_filename[0] ? bs->exact_filename : bs->filename;
-
- full_name = bdrv_get_full_backing_filename_from_filename(backed,
- bs->backing_file,
- &local_error);
- if (full_name) {
- pstrcpy(dest, sz, full_name);
- g_free(full_name);
- } else if (local_error) {
- error_propagate(errp, local_error);
- } else if (sz > 0) {
- *dest = '\0';
- }
+ return bdrv_get_full_backing_filename_from_filename(backed,
+ bs->backing_file,
+ errp);
}
void bdrv_register(BlockDriver *bdrv)
@@ -2387,7 +2375,7 @@
int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options,
const char *bdref_key, Error **errp)
{
- char *backing_filename = g_malloc0(PATH_MAX);
+ char *backing_filename = NULL;
char *bdref_key_dot;
const char *reference = NULL;
int ret = 0;
@@ -2422,7 +2410,7 @@
*/
reference = qdict_get_try_str(parent_options, bdref_key);
if (reference || qdict_haskey(options, "file.filename")) {
- backing_filename[0] = '\0';
+ /* keep backing_filename NULL */
} else if (bs->backing_file[0] == '\0' && qdict_size(options) == 0) {
qobject_unref(options);
goto free_exit;
@@ -2437,8 +2425,7 @@
implicit_backing = !strcmp(bs->auto_backing_file, bs->backing_file);
}
- bdrv_get_full_backing_filename(bs, backing_filename, PATH_MAX,
- &local_err);
+ backing_filename = bdrv_get_full_backing_filename(bs, &local_err);
if (local_err) {
ret = -EINVAL;
error_propagate(errp, local_err);
@@ -2459,9 +2446,8 @@
qdict_put_str(options, "driver", bs->backing_format);
}
- backing_hd = bdrv_open_inherit(*backing_filename ? backing_filename : NULL,
- reference, options, 0, bs, &child_backing,
- errp);
+ backing_hd = bdrv_open_inherit(backing_filename, reference, options, 0, bs,
+ &child_backing, errp);
if (!backing_hd) {
bs->open_flags |= BDRV_O_NO_BACKING;
error_prepend(errp, "Could not open backing file: ");
@@ -4648,7 +4634,6 @@
int is_protocol = 0;
BlockDriverState *curr_bs = NULL;
BlockDriverState *retval = NULL;
- Error *local_error = NULL;
if (!bs || !bs->drv || !backing_file) {
return NULL;
@@ -4668,21 +4653,22 @@
/* If either of the filename paths is actually a protocol, then
* compare unmodified paths; otherwise make paths relative */
if (is_protocol || path_has_protocol(curr_bs->backing_file)) {
+ char *backing_file_full_ret;
+
if (strcmp(backing_file, curr_bs->backing_file) == 0) {
retval = curr_bs->backing->bs;
break;
}
/* Also check against the full backing filename for the image */
- bdrv_get_full_backing_filename(curr_bs, backing_file_full, PATH_MAX,
- &local_error);
- if (local_error == NULL) {
- if (strcmp(backing_file, backing_file_full) == 0) {
+ backing_file_full_ret = bdrv_get_full_backing_filename(curr_bs,
+ NULL);
+ if (backing_file_full_ret) {
+ bool equal = strcmp(backing_file, backing_file_full_ret) == 0;
+ g_free(backing_file_full_ret);
+ if (equal) {
retval = curr_bs->backing->bs;
break;
}
- } else {
- error_free(local_error);
- local_error = NULL;
}
} else {
/* If not an absolute filename path, make it relative to the current
diff --git a/block/qapi.c b/block/qapi.c
index 4623de1..6002a76 100644
--- a/block/qapi.c
+++ b/block/qapi.c
@@ -296,18 +296,10 @@
backing_filename = bs->backing_file;
if (backing_filename[0] != '\0') {
- char *backing_filename2 = g_malloc0(PATH_MAX);
+ char *backing_filename2;
info->backing_filename = g_strdup(backing_filename);
info->has_backing_filename = true;
- bdrv_get_full_backing_filename(bs, backing_filename2, PATH_MAX, &err);
- if (err) {
- /* Can't reconstruct the full backing filename, so we must omit
- * this field and apply a Best Effort to this query. */
- g_free(backing_filename2);
- backing_filename2 = NULL;
- error_free(err);
- err = NULL;
- }
+ backing_filename2 = bdrv_get_full_backing_filename(bs, NULL);
/* Always report the full_backing_filename if present, even if it's the
* same as backing_filename. That they are same is useful info. */
diff --git a/include/block/block.h b/include/block/block.h
index 5f16503..42cc38f 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -487,8 +487,7 @@
void bdrv_get_backing_filename(BlockDriverState *bs,
char *filename, int filename_size);
-void bdrv_get_full_backing_filename(BlockDriverState *bs,
- char *dest, size_t sz, Error **errp);
+char *bdrv_get_full_backing_filename(BlockDriverState *bs, Error **errp);
char *bdrv_get_full_backing_filename_from_filename(const char *backed,
const char *backing,
Error **errp);
