qemu-io: Let command functions return error code
This is basically what everything else in the qemu code base does, so we
can do it here, too.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20180509194302.21585-3-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
diff --git a/include/qemu-io.h b/include/qemu-io.h
index 06cdfbf..7433239 100644
--- a/include/qemu-io.h
+++ b/include/qemu-io.h
@@ -22,7 +22,12 @@
#define CMD_FLAG_GLOBAL ((int)0x80000000) /* don't iterate "args" */
-typedef void (*cfunc_t)(BlockBackend *blk, int argc, char **argv);
+/* Implement a qemu-io command.
+ * Operate on @blk using @argc/@argv as the command's arguments, and
+ * return 0 on success or negative errno on failure.
+ */
+typedef int (*cfunc_t)(BlockBackend *blk, int argc, char **argv);
+
typedef void (*helpfunc_t)(void);
typedef struct cmdinfo {
@@ -41,7 +46,7 @@
extern bool qemuio_misalign;
-void qemuio_command(BlockBackend *blk, const char *cmd);
+int qemuio_command(BlockBackend *blk, const char *cmd);
void qemuio_add_command(const cmdinfo_t *ci);
void qemuio_command_usage(const cmdinfo_t *ci);
