Re: [Libguestfs] [libnbd PATCH v4 16/25] info: Expose extended-headers support through nbdinfo

Add another bit of overall server information, as well as a '--has extended-headers' silent query. For now, the testsuite is written assuming that when nbdkit finally adds extended headers support, it will also add a --no-eh kill switch comparable to its existing --no-sr switch. Signed-off-by: Eric Blake <eblake(a)redhat.com&gt; --- v4: s/can/has/ [Rich] --- info/nbdinfo.pod | 9 +++++++++ info/can.c | 9 +++++++++ info/info-can.sh | 27 +++++++++++++++++++++++++++ info/info-packets.sh | 17 ++++++++++++++++- info/main.c | 7 ++++++- 5 files changed, 67 insertions(+), 2 deletions(-) diff --git a/info/nbdinfo.pod b/info/nbdinfo.pod index 72193c24..2bdd573f 100644 --- a/info/nbdinfo.pod +++ b/info/nbdinfo.pod @@ -86,6 +86,7 @@ the I<--json> parameter: "protocol": "newstyle-fixed", "TLS": false, "structured": true, + "extended": false, "exports": [ { "export-name": "", @@ -165,6 +166,11 @@ Test if the NBD URI connection is using TLS. Test if server has support for structured replies (a prerequisite for supporting block status commands). +=item nbdinfo --has extended-headers URI + +Test if server supports extended headers (a prerequisite for +supporting 64-bit commands; implies structured replies as well). + =item nbdinfo --is rotational URI Test if the server export is backed by something which behaves like a @@ -367,6 +373,8 @@ When using I<--list>, the default is I<--no-content> (since downloading from each export is expensive). To enable content probing use I<--list --content>. +=item B<--has extended-headers> + =item B<--has structured-reply> Test properties of the NBD server connection. The command does not @@ -377,6 +385,7 @@ indicate an error querying the flag). For further information see the L<NBD protocol|https://github.com/NetworkBlockDevice/nbd/blob/master/doc/proto.... and the following libnbd functions: +L<nbd_get_extended_headers_negotiated(3)>, L<nbd_get_structured_replies_negotiated(3)>. =item B<--is read-only> diff --git a/info/can.c b/info/can.c index 8514fd5a..8547ef04 100644 --- a/info/can.c +++ b/info/can.c @@ -50,6 +50,15 @@ do_can (void) strcasecmp (can, "structured_replies") == 0) feature = nbd_get_structured_replies_negotiated (nbd); + else if (strcasecmp (can, "eh") == 0 || + strcasecmp (can, "extended header") == 0 || + strcasecmp (can, "extended-header") == 0 || + strcasecmp (can, "extended_header") == 0 || + strcasecmp (can, "extended headers") == 0 || + strcasecmp (can, "extended-headers") == 0 || + strcasecmp (can, "extended_headers") == 0) + feature = nbd_get_extended_headers_negotiated (nbd); + else if (strcasecmp (can, "readonly") == 0 || strcasecmp (can, "read-only") == 0 || strcasecmp (can, "read_only") == 0) diff --git a/info/info-can.sh b/info/info-can.sh index 13ef1032..5d9f2e89 100755 --- a/info/info-can.sh +++ b/info/info-can.sh @@ -61,6 +61,33 @@ esac EOF test $st = 2 +# --has extended-headers cannot be positively tested until nbdkit gains +# --no-eh support. Otherwise, it is similar to --has structured-reply. + +no_eh= +if nbdkit --no-eh --help >/dev/null 2>/dev/null; then + no_eh=--no-eh + nbdkit -v -U - sh - \ + --run '$VG nbdinfo --has extended-headers "nbd+unix:///?socket=$unixsocket"' <<'EOF' +case "$1" in + get_size) echo 1024 ;; + pread) ;; + *) exit 2 ;; +esac +EOF +fi + +st=0 +nbdkit -v -U - $no_eh sh - \ + --run '$VG nbdinfo --has extended-headers "nbd+unix:///?socket=$unixsocket"' <<'EOF' || st=$? +case "$1" in + get_size) echo 1024 ;; + pread) ;; + *) exit 2 ;; +esac +EOF +test $st = 2 + # --can cache and --can fua require special handling because in # nbdkit-sh-plugin we must print "native" or "none". Also the can_fua # flag is only sent if the export is writable (hence can_write below). diff --git a/info/info-packets.sh b/info/info-packets.sh index 2460052e..410faef8 100755 --- a/info/info-packets.sh +++ b/info/info-packets.sh @@ -27,12 +27,27 @@ requires nbdkit --no-sr memory --version out=info-packets.out cleanup_fn rm -f $out +# Older nbdkit does not support extended headers; --no-eh is a reliable +# witness of whether nbdkit is new enough. + +no_eh= +if nbdkit --no-eh --help >/dev/null 2>/dev/null; then + no_eh=--no-eh +fi + nbdkit --no-sr -U - memory size=1M \ --run '$VG nbdinfo "nbd+unix:///?socket=$unixsocket"' > $out cat $out grep "protocol: .*using simple packets" $out -nbdkit -U - memory size=1M \ +nbdkit $no_eh -U - memory size=1M \ --run '$VG nbdinfo "nbd+unix:///?socket=$unixsocket"' > $out cat $out grep "protocol: .*using structured packets" $out + +if test x != "x$no_eh"; then + nbdkit -U - memory size=1M \ + --run '$VG nbdinfo "nbd+unix:///?socket=$unixsocket"' > $out + cat $out + grep "protocol: .*using extended packets" $out +fi diff --git a/info/main.c b/info/main.c index dbcc5a14..572dd536 100644 --- a/info/main.c +++ b/info/main.c @@ -306,11 +306,13 @@ main (int argc, char *argv[]) const char *protocol; int tls_negotiated; int sr_negotiated; + int eh_negotiated; /* Print per-connection fields. */ protocol = nbd_get_protocol (nbd); tls_negotiated = nbd_get_tls_negotiated (nbd); sr_negotiated = nbd_get_structured_replies_negotiated (nbd); + eh_negotiated = nbd_get_extended_headers_negotiated (nbd); if (!json_output) { if (protocol) { @@ -318,8 +320,9 @@ main (int argc, char *argv[]) fprintf (fp, "protocol: %s", protocol); if (tls_negotiated >= 0) fprintf (fp, " %s TLS", tls_negotiated ? "with" : "without"); - if (sr_negotiated >= 0) + if (eh_negotiated >= 0 && sr_negotiated >= 0) fprintf (fp, ", using %s packets", + eh_negotiated ? "extended" : sr_negotiated ? "structured" : "simple");

fprintf (fp, "\n"); ansi_restore (fp); @@ -337,6 +340,8 @@ main (int argc, char *argv[]) fprintf (fp, "\"TLS\": %s,\n", tls_negotiated ? "true" : "false"); if (sr_negotiated >= 0) fprintf (fp, "\"structured\": %s,\n", sr_negotiated ? "true" : "false"); + if (eh_negotiated >= 0) + fprintf (fp, "\"extended\": %s,\n", eh_negotiated ? "true" : "false"); } if (!list_all) --