util/json: Use json_object_get_uint64() with uint64 support

[justinrernst]

If HAVE_JSON_U64=1, utils/json.c:display_hex() can call json_object_get_int64() on a struct json_object created with json_object_new_uint64(). In the context of 'ndctl list --regions --human', this results in a static value of 0x7fffffffffffffff being displayed for iset_id, as seen in #217.

Correct hex values are observed with the use of json_object_get_uint64(). To support builds against older json-c, use a new static inline function util_json_get_u64() to fallback to json_object_get_int64() if HAVE_JSON_U64=0.

Link: #217
Fixes: 691cd24 ("json: Add support for json_object_new_uint64()")

We observed the 0x7fffffffffffffff value while testing NVDIMMS with RHEL9.2 and RHEL9.3, ndctl version 71.1

# cat /etc/os-release
NAME="Red Hat Enterprise Linux"
VERSION="9.3 (Plow)"
ID="rhel"
ID_LIKE="fedora"
VERSION_ID="9.3"
PLATFORM_ID="platform:el9"
PRETTY_NAME="Red Hat Enterprise Linux 9.3 (Plow)"
ANSI_COLOR="0;31"
LOGO="fedora-logo-icon"
CPE_NAME="cpe:/o:redhat:enterprise_linux:9::baseos"
HOME_URL="https://www.redhat.com/"
DOCUMENTATION_URL="https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/9"
BUG_REPORT_URL="https://bugzilla.redhat.com/"

REDHAT_BUGZILLA_PRODUCT="Red Hat Enterprise Linux 9"
REDHAT_BUGZILLA_PRODUCT_VERSION=9.3
REDHAT_SUPPORT_PRODUCT="Red Hat Enterprise Linux"
REDHAT_SUPPORT_PRODUCT_VERSION="9.3"
# ndctl --version
71.1
# ndctl list -Ru
[
  {
    "dev":"region1",
    "size":"1518.00 GiB (1629.94 GB)",
    "align":"96.00 MiB (100.66 MB)",
    "available_size":"1518.00 GiB (1629.94 GB)",
    "max_available_extent":"1518.00 GiB (1629.94 GB)",
    "type":"pmem",
    "iset_id":"0x7fffffffffffffff",
    "persistence_domain":"memory_controller"
  },
  {
    "dev":"region3",
    "size":"1518.00 GiB (1629.94 GB)",
    "align":"96.00 MiB (100.66 MB)",
    "available_size":"1518.00 GiB (1629.94 GB)",
    "max_available_extent":"1518.00 GiB (1629.94 GB)",
    "type":"pmem",
    "iset_id":"0x7fffffffffffffff",
    "persistence_domain":"memory_controller"
  },
  {
    "dev":"region0",
    "size":"1518.00 GiB (1629.94 GB)",
    "align":"96.00 MiB (100.66 MB)",
    "available_size":"1518.00 GiB (1629.94 GB)",
    "max_available_extent":"1518.00 GiB (1629.94 GB)",
    "type":"pmem",
    "iset_id":"0x7fffffffffffffff",
    "persistence_domain":"memory_controller"
  },
  {
    "dev":"region2",
    "size":"1518.00 GiB (1629.94 GB)",
    "align":"96.00 MiB (100.66 MB)",
    "available_size":"1518.00 GiB (1629.94 GB)",
    "max_available_extent":"1518.00 GiB (1629.94 GB)",
    "type":"pmem",
    "iset_id":"0x7fffffffffffffff",
    "persistence_domain":"memory_controller"
  }
]

[stellarhopper]

@justinrernst This looks good but would you mind sending this as a patch to the mailing list with a proper signoff etc.? (See https://github.com/pmem/ndctl/blob/main/CONTRIBUTING.md )

[justinrernst]

@stellarhopper No problem. Sent!