Commit cb7cf0e3 authored by Ryota Ozaki's avatar Ryota Ozaki Committed by Kevin Wolf
Browse files

qemu-nbd: Improve error reporting 



- 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: default avatarRyota Ozaki <ozaki.ryota@gmail.com>
Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
parent 3abbc4d9

qemu-nbd.c

+24 −10
Original line number Diff line number Diff line
@@ -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);