Re: [Qemu-devel] [RFC PATCH V3 2/5] qapi: add event helper functions

[Wenchao Xia]

于 2014/3/21 6:53, Eric Blake 写道:
On 03/18/2014 11:16 PM, Wenchao Xia wrote:
This file hold some functions that do not need to be generated.
s/hold/holds/
Signed-off-by: Wenchao Xia<wenchaoq...@gmail.com>
---
  include/qapi/qmp-event.h |   25 ++++++++++++++++
  qapi/Makefile.objs       |    1 +
  qapi/qmp-event.c         |   71 ++++++++++++++++++++++++++++++++++++++++++++++
  3 files changed, 97 insertions(+), 0 deletions(-)
  create mode 100644 include/qapi/qmp-event.h
  create mode 100644 qapi/qmp-event.c

diff --git a/include/qapi/qmp-event.h b/include/qapi/qmp-event.h
new file mode 100644
index 0000000..fdf1a7f
--- /dev/null
+++ b/include/qapi/qmp-event.h
@@ -0,0 +1,25 @@
+/*
+ * QMP Event related
+ *
+ * Authors:
+ *  Wenchao Xia<wenchaoq...@gmail.com>
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
+ * See the COPYING.LIB file in the top-level directory.
For the [L]GPL to work, someone must assert copyright.
  Will fix.

+++ b/qapi/qmp-event.c
@@ -0,0 +1,71 @@
+/*
+ * QMP Event related
+ *
+ * Authors:
+ *  Wenchao Xia<wenchaoq...@gmail.com>
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
+ * See the COPYING.LIB file in the top-level directory.
Again, missing an actual use of the word "Copyright".

+
+typedef struct QMPEventFunctions {
+    QMPEventFuncEmit emit;
+} QMPEventFunctions;
+
+QMPEventFunctions qmp_event_functions;
+
+void qmp_event_set_func_emit(QMPEventFuncEmit emit)
+{
+    qmp_event_functions.emit = emit;
+}
+
+QMPEventFuncEmit qmp_event_get_func_emit(void)
+{
+    return qmp_event_functions.emit;
+}
Is this struct a bit overkill, or do you extend it to include other
fields later?
  No other fields will be added in this series, it allow different emit 
function hooked.
Do you mean remove it and put it into generated qapi-event.c?



+    err = qemu_gettimeofday(&tv);
+    if (err<  0) {
+        /* Put -1 to indicate failure of getting host time */
+        tv.tv_sec = tv.tv_usec = -1;
Believe it or not, this is NOT portable.  Let's consider what happens
when tv_sec is int64_t and tv_usec is uint32_t.  Assignments happen
right to left, so tv_usec gets the unsigned value 0xffffffff, then since
all uint32_t values fit in int64_t, integer promotion says that the
value is 0-extended (not sign-extended), and tv_sec is NOT assigned -1.
  Solution: break this into two separate statements:

tv.tv_sec = -1;
tv.tv_usec = -1;
  Good catch, thanks!


+    }
+
+    obj = qobject_from_jsonf("{ 'seconds': %" PRId64 ", "
+                                "'microseconds': %" PRId64 " }",
+                                (int64_t) tv.tv_sec, (int64_t) tv.tv_usec);
Indentation is odd, but that's cosmetic.
  Will fix.