Re: [Qemu-devel] [PATCH V2 1/3] qemu-iotests: add unix socket help program

[Wenchao Xia <xiawenc@linux.vnet.ibm.com>]

于 2013-8-30 19:33, Luiz Capitulino 写道:
> On Fri, 30 Aug 2013 10:42:27 +0800
> Wenchao Xia <xiawenc@linux.vnet.ibm.com> wrote:
>
>> 于 2013-8-29 22:50, Luiz Capitulino 写道:
>>> On Tue, 27 Aug 2013 10:52:09 +0800
>>> Wenchao Xia <xiawenc@linux.vnet.ibm.com> wrote:
>>>
>>>> This program can do a sendmsg call to transfer fd with unix
>>>> socket, which is not supported in python2.
>>>>
>>>> The built binary will not be deleted in clean, but it is a
>>>> existing issue in ./tests, which should be solved in another
>>>> patch.
>>>
>>> Review comments in addition to Eric's.
>>>
>>>>
>>>> Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
>>>> ---
>>>>    configure                              |    2 +-
>>>>    tests/Makefile                         |    4 +-
>>>>    tests/qemu-iotests/socket_scm_helper.c |  119 ++++++++++++++++++++++++++++++++
>>>>    3 files changed, 123 insertions(+), 2 deletions(-)
>>>>    create mode 100644 tests/qemu-iotests/socket_scm_helper.c
>>>>
>>>> diff --git a/configure b/configure
>>>> index 0a55c20..5080c38 100755
>>>> --- a/configure
>>>> +++ b/configure
>>>> @@ -4544,7 +4544,7 @@ if [ "$dtc_internal" = "yes" ]; then
>>>>    fi
>>>>
>>>>    # build tree in object directory in case the source is not in the current directory
>>>> -DIRS="tests tests/tcg tests/tcg/cris tests/tcg/lm32 tests/libqos tests/qapi-schema tests/tcg/xtensa"
>>>> +DIRS="tests tests/tcg tests/tcg/cris tests/tcg/lm32 tests/libqos tests/qapi-schema tests/tcg/xtensa tests/qemu-iotests"
>>>>    DIRS="$DIRS pc-bios/optionrom pc-bios/spapr-rtas pc-bios/s390-ccw"
>>>>    DIRS="$DIRS roms/seabios roms/vgabios"
>>>>    DIRS="$DIRS qapi-generated"
>>>> diff --git a/tests/Makefile b/tests/Makefile
>>>> index baba9e9..d2f3fcb 100644
>>>> --- a/tests/Makefile
>>>> +++ b/tests/Makefile
>>>> @@ -172,6 +172,8 @@ tests/boot-order-test$(EXESUF): tests/boot-order-test.o $(libqos-obj-y)
>>>>    tests/tmp105-test$(EXESUF): tests/tmp105-test.o $(libqos-omap-obj-y)
>>>>    tests/i440fx-test$(EXESUF): tests/i440fx-test.o $(libqos-pc-obj-y)
>>>>    tests/fw_cfg-test$(EXESUF): tests/fw_cfg-test.o $(libqos-pc-obj-y)
>>>> +tests/qemu-iotests/socket_scm_helper$(EXESUF): tests/qemu-iotests/socket_scm_helper.o
>>>> +	$(call LINK, $^)
>>>>
>>>>    # QTest rules
>>>>
>>>> @@ -250,7 +252,7 @@ check-report.html: check-report.xml
>>>>    # Other tests
>>>>
>>>>    .PHONY: check-tests/qemu-iotests-quick.sh
>>>> -check-tests/qemu-iotests-quick.sh: tests/qemu-iotests-quick.sh qemu-img$(EXESUF) qemu-io$(EXESUF)
>>>> +check-tests/qemu-iotests-quick.sh: tests/qemu-iotests-quick.sh qemu-img$(EXESUF) qemu-io$(EXESUF) tests/qemu-iotests/socket_scm_helper$(EXESUF)
>>>>    	$<
>>>>
>>>>    .PHONY: check-tests/test-qapi.py
>>>> diff --git a/tests/qemu-iotests/socket_scm_helper.c b/tests/qemu-iotests/socket_scm_helper.c
>>>> new file mode 100644
>>>> index 0000000..1955a3e
>>>> --- /dev/null
>>>> +++ b/tests/qemu-iotests/socket_scm_helper.c
>>>> @@ -0,0 +1,119 @@
>>>> +/*
>>>> + * SCM_RIGHT with unix socket help program for test
>>>> + *
>>>> + * Copyright IBM, Inc. 2013
>>>> + *
>>>> + * Authors:
>>>> + *  Wenchao Xia    <xiawenc@linux.vnet.ibm.com>
>>>> + *
>>>> + * This work is licensed under the terms of the GNU LGPL, version 2 or later.
>>>> + * See the COPYING.LIB file in the top-level directory.
>>>> + */
>>>> +
>>>> +#include <stdio.h>
>>>> +#include <errno.h>
>>>> +#include <sys/socket.h>
>>>> +#include <sys/un.h>
>>>> +#include <stdlib.h>
>>>> +
>>>> +/* #define SOCKET_SCM_DEBUG */
>>>> +
>>>> +static int send_fd(int fd, int fd_to_send, const char *data, size_t len)
>>>> +{
>>>> +    struct msghdr msg;
>>>> +    struct iovec iov[1];
>>>> +    int ret;
>>>> +    char control[CMSG_SPACE(sizeof(int))];
>>>> +    struct cmsghdr *cmsg;
>>>> +
>>>> +    if (fd < 0) {
>>>> +        fprintf(stderr, "Socket fd is invalid.\n");
>>>> +        return -1;
>>>> +    }
>>>> +    if (fd_to_send < 0) {
>>>> +        fprintf(stderr, "Fd to send is invalid.\n");
>>>> +        return -1;
>>>> +    }
>>>> +    if (data == NULL || len <= 0) {
>>>> +        fprintf(stderr, "Data buffer must be valid.\n");
>>>> +        return -1;
>>>> +    }
>>>
>>> I haven't looked at the test itself yet, but my idea for the helper was
>>> to have something like "pass-fd < file > < qmp-socket >". So, what the
>>> helper does is to open 'file' and pass its fd to 'qmp-socket'. Seems
>>> simpler to me.
>>>
>>     OK, will use that style. Do you think the data parameter should be
>> kept? I added it to let test framework choose one char, which can avoid
>> break the qmp protocol.
>
> If you're passing a QMP command there then it can stay.
>
   OK, I'll remove it, since the python script didn't passing a QMP
command now, but a char which was chosen by script and didn't break the
QMP protocol in the wire.

>>
>>>> +
>>>> +    memset(&msg, 0, sizeof(msg));
>>>> +    memset(control, 0, sizeof(control));
>>>> +
>>>> +    iov[0].iov_base = (void *)data;
>>>> +    iov[0].iov_len = len;
>>>> +
>>>> +    msg.msg_iov = iov;
>>>> +    msg.msg_iovlen = 1;
>>>> +
>>>> +    msg.msg_control = control;
>>>> +    msg.msg_controllen = sizeof(control);
>>>> +
>>>> +    cmsg = CMSG_FIRSTHDR(&msg);
>>>> +
>>>> +    cmsg->cmsg_len = CMSG_LEN(sizeof(int));
>>>> +    cmsg->cmsg_level = SOL_SOCKET;
>>>> +    cmsg->cmsg_type = SCM_RIGHTS;
>>>> +    memcpy(CMSG_DATA(cmsg), &fd, sizeof(int));
>>>> +
>>>> +    do {
>>>> +        ret = sendmsg(fd, &msg, 0);
>>>> +    } while (ret < 0 && errno == EINTR);
>>>> +
>>>> +    if (ret < 0) {
>>>> +        fprintf(stderr, "Failed to send msg, reason: %s.\n", strerror(errno));
>>>> +    }
>>>> +
>>>> +    return ret;
>>>> +}
>>>> +
>>>> +/*
>>>> + * To make things simple, the caller need to specify:
>>>> + * 1. socket fd.
>>>> + * 2. fd to send.
>>>> + * 3. msg to send.
>>>> + */
>>>> +int main(int argc, char **argv, char **envp)
>>>> +{
>>>> +    int sock, fd, ret, buflen;
>>>> +    const char *buf;
>>>> +#ifdef SOCKET_SCM_DEBUG
>>>> +    int i;
>>>> +    for (i = 0; i < argc; i++) {
>>>> +        fprintf(stderr, "Parameter %d: %s.\n", i, argv[i]);
>>>> +    }
>>>> +#endif
>>>> +
>>>> +    if (argc < 4) {
>>>> +        fprintf(stderr,
>>>> +                "Invalid parameter, use it as:\n"
>>>> +                "%s SOCKET_FD FD_TO_SEND MSG.\n",
>>>> +                argv[0]);
>>>> +        return 1;
>>>> +    }
>>>
>>> Some like "usage: %s < socket-fd > < fd-to-send > < msg >\n" is more
>>> readable, IMO.
>>>
>>     It is better, will use that.
>>
>>>> +
>>>> +    errno = 0;
>>>> +    sock = strtol(argv[1], NULL, 10);
>>>> +    if (errno) {
>>>> +        fprintf(stderr, "Failed in strtol for socket fd, reason: %s.\n",
>>>> +                strerror(errno));
>>>> +        return 1;
>>>> +    }
>>>
>>> Apart from what Eric suggested, you could move this to a function.
>>>
>>     OK.
>>
>>>> +    fd = strtol(argv[2], NULL, 10);
>>>> +    if (errno) {
>>>> +        fprintf(stderr, "Failed in strtol for fd to send, reason: %s.\n",
>>>> +                strerror(errno));
>>>> +        return 1;
>>>> +    }
>>>> +
>>>> +    buf = argv[3];
>>>> +    buflen = strlen(buf);
>>>> +
>>>> +    ret = send_fd(sock, fd, buf, buflen);
>>>> +    if (ret < 0) {
>>>> +        return 1;
>>>> +    }
>>>> +    return 0;
>>>> +}
>>>
>>
>>
>


-- 
Best Regards

Wenchao Xia