From 92ba1401e0f81ea170803045c1ae366bf5d9d87e Mon Sep 17 00:00:00 2001 From: Laszlo Ersek Date: Tue, 20 May 2014 13:39:42 +0200 Subject: dump: simplify write_start_flat_header() 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(-) (limited to 'dump.c') diff --git a/dump.c b/dump.c index ac4505ec8..6dec8d2cf 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; } -- cgit v1.2.3