From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1OAPGj-0007Jo-E7 for qemu-devel@nongnu.org; Fri, 07 May 2010 11:15:13 -0400 Received: from [140.186.70.92] (port=54652 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1OAPGZ-0007FA-Ib for qemu-devel@nongnu.org; Fri, 07 May 2010 11:15:12 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69) (envelope-from ) id 1OAPGP-0006tq-KQ for qemu-devel@nongnu.org; Fri, 07 May 2010 11:15:03 -0400 Received: from mx1.redhat.com ([209.132.183.28]:23485) by eggs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1OAPGM-0006tU-Ir for qemu-devel@nongnu.org; Fri, 07 May 2010 11:14:53 -0400 From: Kevin Wolf Date: Fri, 7 May 2010 17:13:58 +0200 Message-Id: <1273245247-24827-3-git-send-email-kwolf@redhat.com> In-Reply-To: <1273245247-24827-1-git-send-email-kwolf@redhat.com> References: <1273245247-24827-1-git-send-email-kwolf@redhat.com> Subject: [Qemu-devel] [PATCH 02/11] qemu-nbd: Improve error reporting List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: aliguori@linux.vnet.ibm.com Cc: kwolf@redhat.com, qemu-devel@nongnu.org From: Ryota Ozaki - use err(3) instead of errx(3) if errno is available to report why failed - let fail prior to daemon(3) if opening a nbd file is likely to fail after daemonizing to avoid silent failure exit - add missing 'ret = 1' when unix_socket_outgoing failed Signed-off-by: Ryota Ozaki Signed-off-by: Kevin Wolf --- qemu-nbd.c | 34 ++++++++++++++++++++++++---------- 1 files changed, 24 insertions(+), 10 deletions(-) diff --git a/qemu-nbd.c b/qemu-nbd.c index 25aa913..4e607cf 100644 --- a/qemu-nbd.c +++ b/qemu-nbd.c @@ -112,9 +112,12 @@ static int find_partition(BlockDriverState *bs, int partition, uint8_t data[512]; int i; int ext_partnum = 4; + int ret; - if (bdrv_read(bs, 0, data, 1)) - errx(EXIT_FAILURE, "error while reading"); + if ((ret = bdrv_read(bs, 0, data, 1)) < 0) { + errno = -ret; + err(EXIT_FAILURE, "error while reading"); + } if (data[510] != 0x55 || data[511] != 0xaa) { errno = -EINVAL; @@ -132,8 +135,10 @@ static int find_partition(BlockDriverState *bs, int partition, uint8_t data1[512]; int j; - if (bdrv_read(bs, mbr[i].start_sector_abs, data1, 1)) - errx(EXIT_FAILURE, "error while reading"); + if ((ret = bdrv_read(bs, mbr[i].start_sector_abs, data1, 1)) < 0) { + errno = -ret; + err(EXIT_FAILURE, "error while reading"); + } for (j = 0; j < 4; j++) { read_partition(&data1[446 + 16 * j], &ext[j]); @@ -316,7 +321,7 @@ int main(int argc, char **argv) if (disconnect) { fd = open(argv[optind], O_RDWR); if (fd == -1) - errx(EXIT_FAILURE, "Cannot open %s", argv[optind]); + err(EXIT_FAILURE, "Cannot open %s", argv[optind]); nbd_disconnect(fd); @@ -333,23 +338,30 @@ int main(int argc, char **argv) if (bs == NULL) return 1; - if (bdrv_open(bs, argv[optind], flags, NULL) < 0) - return 1; + if ((ret = bdrv_open(bs, argv[optind], flags, NULL)) < 0) { + errno = -ret; + err(EXIT_FAILURE, "Failed to bdrv_open '%s'", argv[optind]); + } fd_size = bs->total_sectors * 512; if (partition != -1 && find_partition(bs, partition, &dev_offset, &fd_size)) - errx(EXIT_FAILURE, "Could not find partition %d", partition); + err(EXIT_FAILURE, "Could not find partition %d", partition); if (device) { pid_t pid; int sock; + /* want to fail before daemonizing */ + if (access(device, R_OK|W_OK) == -1) { + err(EXIT_FAILURE, "Could not access '%s'", device); + } + if (!verbose) { /* detach client and server */ if (daemon(0, 0) == -1) { - errx(EXIT_FAILURE, "Failed to daemonize"); + err(EXIT_FAILURE, "Failed to daemonize"); } } @@ -372,8 +384,10 @@ int main(int argc, char **argv) do { sock = unix_socket_outgoing(socket); if (sock == -1) { - if (errno != ENOENT && errno != ECONNREFUSED) + if (errno != ENOENT && errno != ECONNREFUSED) { + ret = 1; goto out; + } sleep(1); /* wait children */ } } while (sock == -1); -- 1.6.6.1