Commit cb6b1a3f authored by Eric Blake's avatar Eric Blake
Browse files

nbd/client: Use error_prepend() correctly 

When using error prepend(), it is necessary to end with a space
in the format string; otherwise, messages come out incorrectly,
such as when connecting to a socket that hangs up immediately:

can't open device nbd://localhost:10809/

: Failed to read dataUnexpected end-of-file before all bytes were read

Originally botched in commit e44ed99d, then several more instances
added in the meantime.

Pre-existing and not fixed here: we are inconsistent on capitalization;
some of our messages start with lower case, and others start with upper,
although the use of error_prepend() is much nicer to read when all
fragments consistently start with lower.

CC: qemu-stable@nongnu.org
Signed-off-by: default avatarEric Blake <eblake@redhat.com>
Message-Id: <20171113152424.25381-1-eblake@redhat.com>
Reviewed-by: default avatarVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: default avatarMarkus Armbruster <armbru@redhat.com>
parent 08ace1d7

nbd/client.c

+26 −24
Original line number Diff line number Diff line
@@ -79,12 +79,12 @@ static int nbd_send_option_request(QIOChannel *ioc, uint32_t opt, 
    stl_be_p(&req.length, len);



    if (nbd_write(ioc, &req, sizeof(req), errp) < 0) {

        error_prepend(errp, "Failed to send option request header");

        error_prepend(errp, "Failed to send option request header: ");

        return -1;

    }



    if (len && nbd_write(ioc, (char *) data, len, errp) < 0) {

        error_prepend(errp, "Failed to send option request data");

        error_prepend(errp, "Failed to send option request data: ");

        return -1;

    }
@@ -113,7 +113,7 @@ static int nbd_receive_option_reply(QIOChannel *ioc, uint32_t opt, 
{

    QEMU_BUILD_BUG_ON(sizeof(*reply) != 20);

    if (nbd_read(ioc, reply, sizeof(*reply), errp) < 0) {

        error_prepend(errp, "failed to read option reply");

        error_prepend(errp, "failed to read option reply: ");

        nbd_send_opt_abort(ioc);

        return -1;

    }
@@ -166,7 +166,7 @@ static int nbd_handle_reply_err(QIOChannel *ioc, nbd_opt_reply *reply, 
        msg = g_malloc(reply->length + 1);

        if (nbd_read(ioc, msg, reply->length, errp) < 0) {

            error_prepend(errp, "failed to read option error 0x%" PRIx32

                          " (%s) message",

                          " (%s) message: ",

                          reply->type, nbd_rep_lookup(reply->type));

            goto cleanup;

        }
@@ -277,7 +277,7 @@ static int nbd_receive_list(QIOChannel *ioc, const char *want, bool *match, 
        return -1;

    }

    if (nbd_read(ioc, &namelen, sizeof(namelen), errp) < 0) {

        error_prepend(errp, "failed to read option name length");

        error_prepend(errp, "failed to read option name length: ");

        nbd_send_opt_abort(ioc);

        return -1;

    }
@@ -290,7 +290,8 @@ static int nbd_receive_list(QIOChannel *ioc, const char *want, bool *match, 
    }

    if (namelen != strlen(want)) {

        if (nbd_drop(ioc, len, errp) < 0) {

            error_prepend(errp, "failed to skip export name with wrong length");

            error_prepend(errp,

                          "failed to skip export name with wrong length: ");

            nbd_send_opt_abort(ioc);

            return -1;

        }
@@ -299,14 +300,14 @@ static int nbd_receive_list(QIOChannel *ioc, const char *want, bool *match, 


    assert(namelen < sizeof(name));

    if (nbd_read(ioc, name, namelen, errp) < 0) {

        error_prepend(errp, "failed to read export name");

        error_prepend(errp, "failed to read export name: ");

        nbd_send_opt_abort(ioc);

        return -1;

    }

    name[namelen] = '\0';

    len -= namelen;

    if (nbd_drop(ioc, len, errp) < 0) {

        error_prepend(errp, "failed to read export description");

        error_prepend(errp, "failed to read export description: ");

        nbd_send_opt_abort(ioc);

        return -1;

    }
@@ -390,7 +391,7 @@ static int nbd_opt_go(QIOChannel *ioc, const char *wantname, 
            return -1;

        }

        if (nbd_read(ioc, &type, sizeof(type), errp) < 0) {

            error_prepend(errp, "failed to read info type");

            error_prepend(errp, "failed to read info type: ");

            nbd_send_opt_abort(ioc);

            return -1;

        }
@@ -405,13 +406,13 @@ static int nbd_opt_go(QIOChannel *ioc, const char *wantname, 
                return -1;

            }

            if (nbd_read(ioc, &info->size, sizeof(info->size), errp) < 0) {

                error_prepend(errp, "failed to read info size");

                error_prepend(errp, "failed to read info size: ");

                nbd_send_opt_abort(ioc);

                return -1;

            }

            be64_to_cpus(&info->size);

            if (nbd_read(ioc, &info->flags, sizeof(info->flags), errp) < 0) {

                error_prepend(errp, "failed to read info flags");

                error_prepend(errp, "failed to read info flags: ");

                nbd_send_opt_abort(ioc);

                return -1;

            }
@@ -428,7 +429,7 @@ static int nbd_opt_go(QIOChannel *ioc, const char *wantname, 
            }

            if (nbd_read(ioc, &info->min_block, sizeof(info->min_block),

                         errp) < 0) {

                error_prepend(errp, "failed to read info minimum block size");

                error_prepend(errp, "failed to read info minimum block size: ");

                nbd_send_opt_abort(ioc);

                return -1;

            }
@@ -441,7 +442,8 @@ static int nbd_opt_go(QIOChannel *ioc, const char *wantname, 
            }

            if (nbd_read(ioc, &info->opt_block, sizeof(info->opt_block),

                         errp) < 0) {

                error_prepend(errp, "failed to read info preferred block size");

                error_prepend(errp,

                              "failed to read info preferred block size: ");

                nbd_send_opt_abort(ioc);

                return -1;

            }
@@ -455,7 +457,7 @@ static int nbd_opt_go(QIOChannel *ioc, const char *wantname, 
            }

            if (nbd_read(ioc, &info->max_block, sizeof(info->max_block),

                         errp) < 0) {

                error_prepend(errp, "failed to read info maximum block size");

                error_prepend(errp, "failed to read info maximum block size: ");

                nbd_send_opt_abort(ioc);

                return -1;

            }
@@ -467,7 +469,7 @@ static int nbd_opt_go(QIOChannel *ioc, const char *wantname, 
        default:

            trace_nbd_opt_go_info_unknown(type, nbd_info_lookup(type));

            if (nbd_drop(ioc, len, errp) < 0) {

                error_prepend(errp, "Failed to read info payload");

                error_prepend(errp, "Failed to read info payload: ");

                nbd_send_opt_abort(ioc);

                return -1;

            }
@@ -618,7 +620,7 @@ int nbd_receive_negotiate(QIOChannel *ioc, const char *name, 
    }



    if (nbd_read(ioc, buf, 8, errp) < 0) {

        error_prepend(errp, "Failed to read data");

        error_prepend(errp, "Failed to read data: ");

        goto fail;

    }
@@ -637,7 +639,7 @@ int nbd_receive_negotiate(QIOChannel *ioc, const char *name, 
    }



    if (nbd_read(ioc, &magic, sizeof(magic), errp) < 0) {

        error_prepend(errp, "Failed to read magic");

        error_prepend(errp, "Failed to read magic: ");

        goto fail;

    }

    magic = be64_to_cpu(magic);
@@ -649,7 +651,7 @@ int nbd_receive_negotiate(QIOChannel *ioc, const char *name, 
        bool fixedNewStyle = false;



        if (nbd_read(ioc, &globalflags, sizeof(globalflags), errp) < 0) {

            error_prepend(errp, "Failed to read server flags");

            error_prepend(errp, "Failed to read server flags: ");

            goto fail;

        }

        globalflags = be16_to_cpu(globalflags);
@@ -665,7 +667,7 @@ int nbd_receive_negotiate(QIOChannel *ioc, const char *name, 
        /* client requested flags */

        clientflags = cpu_to_be32(clientflags);

        if (nbd_write(ioc, &clientflags, sizeof(clientflags), errp) < 0) {

            error_prepend(errp, "Failed to send clientflags field");

            error_prepend(errp, "Failed to send clientflags field: ");

            goto fail;

        }

        if (tlscreds) {
@@ -727,13 +729,13 @@ int nbd_receive_negotiate(QIOChannel *ioc, const char *name, 


        /* Read the response */

        if (nbd_read(ioc, &info->size, sizeof(info->size), errp) < 0) {

            error_prepend(errp, "Failed to read export length");

            error_prepend(errp, "Failed to read export length: ");

            goto fail;

        }

        be64_to_cpus(&info->size);



        if (nbd_read(ioc, &info->flags, sizeof(info->flags), errp) < 0) {

            error_prepend(errp, "Failed to read export flags");

            error_prepend(errp, "Failed to read export flags: ");

            goto fail;

        }

        be16_to_cpus(&info->flags);
@@ -750,13 +752,13 @@ int nbd_receive_negotiate(QIOChannel *ioc, const char *name, 
        }



        if (nbd_read(ioc, &info->size, sizeof(info->size), errp) < 0) {

            error_prepend(errp, "Failed to read export length");

            error_prepend(errp, "Failed to read export length: ");

            goto fail;

        }

        be64_to_cpus(&info->size);



        if (nbd_read(ioc, &oldflags, sizeof(oldflags), errp) < 0) {

            error_prepend(errp, "Failed to read export flags");

            error_prepend(errp, "Failed to read export flags: ");

            goto fail;

        }

        be32_to_cpus(&oldflags);
@@ -772,7 +774,7 @@ int nbd_receive_negotiate(QIOChannel *ioc, const char *name, 


    trace_nbd_receive_negotiate_size_flags(info->size, info->flags);

    if (zeroes && nbd_drop(ioc, 124, errp) < 0) {

        error_prepend(errp, "Failed to read reserved block");

        error_prepend(errp, "Failed to read reserved block: ");

        goto fail;

    }

    rc = 0;