This will make sure no error will be missed as long as callers always
check for qemu_fclose() return value. For reference, this is the
complete list of qemu_fclose() callers:
- exec_close(): already fixed to check for negative values, not -1
- migrate_fd_cleanup(): already fixed to consider only negative values
as error, not any non-zero value
- exec_accept_incoming_migration(): no return value check (yet)
- fd_accept_incoming_migration(): no return value check (yet)
- tcp_accept_incoming_migration(): no return value check (yet)
- unix_accept_incoming_migration(): no return value check (yet)
- do_savevm(): no return value check (yet)
- load_vmstate(): no return value check (yet)
Signed-off-by: Eduardo Habkost <ehabk...@redhat.com>
---
savevm.c | 46 +++++++++++++++++++++++++++++++++++++++++++---
1 files changed, 43 insertions(+), 3 deletions(-)
diff --git a/savevm.c b/savevm.c
index dc3311b..3c746a6 100644
--- a/savevm.c
+++ b/savevm.c
@@ -436,6 +436,21 @@ void qemu_file_set_error(QEMUFile *f, int ret)
f->last_error = ret;
}
+/** Sets last_error conditionally
+ *
+ * Sets last_error only if ret is negative _and_ no error
+ * was set before.
+ */
+static void qemu_file_set_if_error(QEMUFile *f, int ret)
+{
+ if (ret < 0 && !f->last_error)
+ qemu_file_set_error(f, ret);
+}
+
+/** Flushes QEMUFile buffer
+ *
+ * In case of error, last_error is set.
+ */
void qemu_fflush(QEMUFile *f)
{
if (!f->put_buffer)
@@ -480,12 +495,37 @@ static void qemu_fill_buffer(QEMUFile *f)
qemu_file_set_error(f, len);
}
-int qemu_fclose(QEMUFile *f)
+/** Calls close function and set last_error if needed
+ *
+ * Internal function. qemu_fflush() must be called before this.
+ *
+ * Returns f->close() return value, or 0 if close function is not set.
+ */
+static int qemu_close(QEMUFile *f)
{
int ret = 0;
- qemu_fflush(f);
- if (f->close)
+ if (f->close) {
ret = f->close(f->opaque);
+ qemu_file_set_if_error(f, ret);
+ }
+ return ret;
+}
+
+/** Closes the file
+ *
+ * Returns negative error value if any error happened on previous operations or
+ * while closing the file. Returns 0 or positive number on success.
+ *
+ * The meaning of return value on success depends on the specific backend
+ * being used.
+ */
+int qemu_fclose(QEMUFile *f)
+{
+ int ret;
+ qemu_fflush(f);
+ ret = qemu_close(f);
+ if (f->last_error)
+ ret = f->last_error;
g_free(f);
return ret;
}
--
1.7.3.2
