Re: [PATCH v2 03/13] storage file: add qcow2 data-file path parsing from header
On Sat, Sep 07, 2024 at 17:15:21 +0300, Nikolai Barybin via Devel wrote:
Signed-off-by: Nikolai Barybin <nikolai.barybin(a)virtuozzo.com>
---
src/storage_file/storage_file_probe.c | 53 +++++++++++++++++++++++++--
1 file changed, 49 insertions(+), 4 deletions(-)
diff --git a/src/storage_file/storage_file_probe.c
b/src/storage_file/storage_file_probe.c
index 4792b9fdff..21430d18aa 100644
--- a/src/storage_file/storage_file_probe.c
+++ b/src/storage_file/storage_file_probe.c
@@ -106,6 +106,7 @@ qcow2GetClusterSize(const char *buf,
size_t buf_size);
static int qcowXGetBackingStore(char **, int *,
const char *, size_t);
+static int qcowXGetDataFile(char **, char *, int, size_t);
data file is a qcow2 only feature so calling this 'qcowX' makes no sense
as it won't be reused.
static int qcow2GetFeatures(virBitmap **features, int format,
char *buf, ssize_t len);
static int vmdk4GetBackingStore(char **, int *,
@@ -393,7 +395,8 @@ cowGetBackingStore(char **res,
static int
qcow2GetExtensions(const char *buf,
size_t buf_size,
- int *backingFormat)
+ int *backingFormat,
+ char **dataFilePath)
{
size_t offset;
size_t extension_start;
@@ -488,6 +491,17 @@ qcow2GetExtensions(const char *buf,
break;
}
+ case QCOW2_HDR_EXTENSION_DATA_FILE_NAME: {
+ g_autofree char *tmp = NULL;
'tmp' is unused.
+ if (!dataFilePath)
+ break;
+
+ *(char **)dataFilePath = g_new0(char, len + 1);
No need for that amount of typecasts since 'dataFilePath' is aready 'char
**'
+ memcpy(*(char **)dataFilePath, buf + offset, len);
same here.
+ (*((char **)dataFilePath))[len] = '\0';
This is not needed as g_new0 allocates a zeroed-out buffer.
+ break;
+ }
+
case QCOW2_HDR_EXTENSION_END:
return 0;
}
@@ -554,9 +568,34 @@ qcowXGetBackingStore(char **res,
memcpy(*res, buf + offset, size);
(*res)[size] = '\0';
- if (qcow2GetExtensions(buf, buf_size, format) < 0)
+ if (qcow2GetExtensions(buf, buf_size, format, NULL) < 0)
+ return 0;
+
+ return 0;
+}
+
+
+static int
+qcowXGetDataFile(char **res,
+ char *buf,
+ int format,
+ size_t buf_size)
+{
+ virBitmap *features = NULL;
+ char *filename = NULL;
+ *res = NULL;
+
+ if (buf_size < QCOW2v3_HDR_FEATURES_INCOMPATIBLE + 8)
return 0;
+ ignore_value(qcow2GetFeatures(&features, format, buf, buf_size));
'qcowXGetDataFile' gets called one block before 'qcow2GetFeatures' would
be called via
'fileTypeInfo[meta->format].getFeatures(&meta->features,'
but here you do it again. Restrucutre the code so that iut doesn't need
to do this twice.
+ if (features && virBitmapIsBitSet(features,
VIR_STORAGE_FILE_FEATURE_DATA_FILE)) {
+ if (qcow2GetExtensions(buf, buf_size, NULL, &filename) < 0)
So 'filename' will be filled with an allocated buffer ...
+ return 0;
+
+ *res = g_strdup(filename);
... you'll dup it (which is wasteful) and then leak the original.
+ }
+
return 0;
}
@@ -963,6 +1002,12 @@ virStorageFileProbeGetMetadata(virStorageSource *meta,
meta->backingStoreRawFormat = format;
}
+ VIR_FREE(meta->dataFileRaw);
+ if (fileTypeInfo[meta->format].getDataFile != NULL) {
+ fileTypeInfo[meta->format].getDataFile(&meta->dataFileRaw,
+ buf, meta->format, len);
+ }
+
g_clear_pointer(&meta->features, virBitmapFree);
if (fileTypeInfo[meta->format].getFeatures != NULL &&
fileTypeInfo[meta->format].getFeatures(&meta->features,
meta->format, buf, len) < 0)
--
2.43.5