Anthony PERARD
2012-Feb-20 17:28 UTC
[PATCH V2] libxl_qmp: Handle unexpected end-of-socket
When read() return 0, the current code just tries again. But this leads to an
infinite loop if QEMU died too soon.
Also, retry select if a signal was caught.
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
---
change with v1:
- remove the introduced goto in favor of a "continue".
tools/libxl/libxl_qmp.c | 5 ++++-
1 files changed, 4 insertions(+), 1 deletions(-)
diff --git a/tools/libxl/libxl_qmp.c b/tools/libxl/libxl_qmp.c
index e0642e3..a974afe 100644
--- a/tools/libxl/libxl_qmp.c
+++ b/tools/libxl/libxl_qmp.c
@@ -390,13 +390,16 @@ static int qmp_next(libxl__gc *gc, libxl__qmp_handler
*qmp)
LIBXL__LOG(qmp->ctx, LIBXL__LOG_ERROR, "timeout");
return -1;
} else if (ret < 0) {
+ if (errno == EINTR)
+ continue;
LIBXL__LOG_ERRNO(qmp->ctx, LIBXL__LOG_ERROR, "Select
error");
return -1;
}
rd = read(qmp->qmp_fd, qmp->buffer, QMP_RECEIVE_BUFFER_SIZE);
if (rd == 0) {
- continue;
+ LIBXL__LOG(qmp->ctx, LIBXL__LOG_ERROR, "Unexpected end of
socket");
+ return -1;
} else if (rd < 0) {
LIBXL__LOG_ERRNO(qmp->ctx, LIBXL__LOG_ERROR, "Socket read
error");
return rd;
--
tg: (75f1fb7..) fix/qmp-end-of-socket (depends on: master)
Ian Jackson
2012-Feb-20 17:53 UTC
Re: [PATCH V2] libxl_qmp: Handle unexpected end-of-socket
Anthony PERARD writes ("[Xen-devel] [PATCH V2] libxl_qmp: Handle unexpected
end-of-socket"):> When read() return 0, the current code just tries again. But this leads to
an
> infinite loop if QEMU died too soon.
>
> Also, retry select if a signal was caught.
>
> Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>