storage: prepare for refactoring

virStorageFileGetMetadataFromFD is the only caller of
virStorageFileGetMetadataFromBuf; and it doesn't care about the
difference between a return of 0 (total success) or 1
(metadata was inconsistent, but pointer was populated as best
as possible); only about a return of -1 (could not read metadata
or out of memory).  Changing the return type, and normalizing
the variable names used, will make merging the functions easier
in the next commit.

* src/util/virstoragefile.c (virStorageFileGetMetadataFromBuf):
Change return value, and rename some variables.
(virStorageFileGetMetadataFromFD): Rename some variables.
This commit is contained in:
Eric Blake 2013-02-09 06:41:01 -07:00
parent 5e4946d4d9
commit b7df4f92d6

View File

@ -657,13 +657,15 @@ cleanup:
}
static int
static virStorageFileMetadataPtr
virStorageFileGetMetadataFromBuf(int format,
const char *path,
unsigned char *buf,
size_t buflen,
size_t len,
virStorageFileMetadata *meta)
{
virStorageFileMetadata *ret = NULL;
VIR_DEBUG("path=%s format=%d", path, format);
/* XXX we should consider moving virStorageBackendUpdateVolInfo
@ -671,14 +673,13 @@ virStorageFileGetMetadataFromBuf(int format,
*/
if (format <= VIR_STORAGE_FILE_NONE ||
format >= VIR_STORAGE_FILE_LAST ||
!fileTypeInfo[format].magic) {
return 0;
}
!fileTypeInfo[format].magic)
goto done;
/* Optionally extract capacity from file */
if (fileTypeInfo[format].sizeOffset != -1) {
if ((fileTypeInfo[format].sizeOffset + 8) > buflen)
return 1;
if ((fileTypeInfo[format].sizeOffset + 8) > len)
goto done;
if (fileTypeInfo[format].endian == LV_LITTLE_ENDIAN)
meta->capacity = virReadBufInt64LE(buf +
@ -689,7 +690,7 @@ virStorageFileGetMetadataFromBuf(int format,
/* Avoid unlikely, but theoretically possible overflow */
if (meta->capacity > (ULLONG_MAX /
fileTypeInfo[format].sizeMultiplier))
return 1;
goto done;
meta->capacity *= fileTypeInfo[format].sizeMultiplier;
}
@ -704,14 +705,14 @@ virStorageFileGetMetadataFromBuf(int format,
if (fileTypeInfo[format].getBackingStore != NULL) {
char *backing;
int backingFormat;
int ret = fileTypeInfo[format].getBackingStore(&backing,
int store = fileTypeInfo[format].getBackingStore(&backing,
&backingFormat,
buf, buflen);
if (ret == BACKING_STORE_INVALID)
return 1;
buf, len);
if (store == BACKING_STORE_INVALID)
goto done;
if (ret == BACKING_STORE_ERROR)
return -1;
if (store == BACKING_STORE_ERROR)
goto cleanup;
meta->backingStoreIsFile = false;
if (backing != NULL) {
@ -719,7 +720,7 @@ virStorageFileGetMetadataFromBuf(int format,
if (meta->backingStore == NULL) {
virReportOOMError();
VIR_FREE(backing);
return -1;
goto cleanup;
}
if (virBackingStoreIsFile(backing)) {
meta->backingStoreIsFile = true;
@ -744,7 +745,10 @@ virStorageFileGetMetadataFromBuf(int format,
}
}
return 0;
done:
ret = meta;
cleanup:
return ret;
}
@ -858,7 +862,7 @@ virStorageFileGetMetadataFromFD(const char *path,
int format)
{
virStorageFileMetadata *meta = NULL;
unsigned char *head = NULL;
unsigned char *buf = NULL;
ssize_t len = STORAGE_MAX_HEAD;
virStorageFileMetadata *ret = NULL;
struct stat sb;
@ -884,18 +888,18 @@ virStorageFileGetMetadataFromFD(const char *path,
goto cleanup;
}
if (VIR_ALLOC_N(head, len) < 0) {
if (VIR_ALLOC_N(buf, len) < 0) {
virReportOOMError();
goto cleanup;
}
if ((len = read(fd, head, len)) < 0) {
if ((len = read(fd, buf, len)) < 0) {
virReportSystemError(errno, _("cannot read header '%s'"), path);
goto cleanup;
}
if (format == VIR_STORAGE_FILE_AUTO)
format = virStorageFileProbeFormatFromBuf(path, head, len);
format = virStorageFileProbeFormatFromBuf(path, buf, len);
if (format <= VIR_STORAGE_FILE_NONE ||
format >= VIR_STORAGE_FILE_LAST) {
@ -904,14 +908,14 @@ virStorageFileGetMetadataFromFD(const char *path,
goto cleanup;
}
if (virStorageFileGetMetadataFromBuf(format, path, head, len, meta) < 0)
if (!virStorageFileGetMetadataFromBuf(format, path, buf, len, meta))
goto cleanup;
ret = meta;
meta = NULL;
cleanup:
virStorageFileFreeMetadata(meta);
VIR_FREE(head);
VIR_FREE(buf);
return ret;
}