From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:44779) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Wujs3-0005i8-Ey for qemu-devel@nongnu.org; Wed, 11 Jun 2014 10:51:34 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Wujrr-00086Y-JM for qemu-devel@nongnu.org; Wed, 11 Jun 2014 10:51:23 -0400 Received: from mx1.redhat.com ([209.132.183.28]:38078) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Wujrr-00086N-Ad for qemu-devel@nongnu.org; Wed, 11 Jun 2014 10:51:11 -0400 From: Luiz Capitulino Date: Wed, 11 Jun 2014 10:50:47 -0400 Message-Id: <1402498262-20521-3-git-send-email-lcapitulino@redhat.com> In-Reply-To: <1402498262-20521-1-git-send-email-lcapitulino@redhat.com> References: <1402498262-20521-1-git-send-email-lcapitulino@redhat.com> Subject: [Qemu-devel] [PULL 02/17] dump: simplify write_start_flat_header() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: peter.maydell@linaro.org Cc: qemu-devel@nongnu.org, anthony@codemonkey.ws From: Laszlo Ersek Currently, the function - defines and populates an auto variable of type MakedumpfileHeader - allocates and zeroes a buffer of size MAX_SIZE_MDF_HEADER (4096) - copies the former into the latter (covering an initial portion of the latter) Fill in the MakedumpfileHeader structure in its final place (the alignment is OK because the structure lives at the address returned by g_malloc0()). Approximately-suggested-by: Luiz Capitulino Signed-off-by: Laszlo Ersek Reviewed-by: Paolo Bonzini Signed-off-by: Luiz Capitulino --- dump.c | 20 +++++++++----------- 1 file changed, 9 insertions(+), 11 deletions(-) diff --git a/dump.c b/dump.c index ac4505e..6dec8d2 100644 --- a/dump.c +++ b/dump.c @@ -711,27 +711,25 @@ static int create_vmcore(DumpState *s) static int write_start_flat_header(int fd) { - uint8_t *buf; - MakedumpfileHeader mh; + MakedumpfileHeader *mh; int ret = 0; - memset(&mh, 0, sizeof(mh)); - memcpy(mh.signature, MAKEDUMPFILE_SIGNATURE, - MIN(sizeof mh.signature, sizeof MAKEDUMPFILE_SIGNATURE)); + QEMU_BUILD_BUG_ON(sizeof *mh > MAX_SIZE_MDF_HEADER); + mh = g_malloc0(MAX_SIZE_MDF_HEADER); - mh.type = cpu_to_be64(TYPE_FLAT_HEADER); - mh.version = cpu_to_be64(VERSION_FLAT_HEADER); + memcpy(mh->signature, MAKEDUMPFILE_SIGNATURE, + MIN(sizeof mh->signature, sizeof MAKEDUMPFILE_SIGNATURE)); - buf = g_malloc0(MAX_SIZE_MDF_HEADER); - memcpy(buf, &mh, sizeof(mh)); + mh->type = cpu_to_be64(TYPE_FLAT_HEADER); + mh->version = cpu_to_be64(VERSION_FLAT_HEADER); size_t written_size; - written_size = qemu_write_full(fd, buf, MAX_SIZE_MDF_HEADER); + written_size = qemu_write_full(fd, mh, MAX_SIZE_MDF_HEADER); if (written_size != MAX_SIZE_MDF_HEADER) { ret = -1; } - g_free(buf); + g_free(mh); return ret; } -- 1.9.3