meson: add option for building with json-c

Also disable it immediately for the mingw build because it's not
available there.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>

libvirt.spec.in

@@ -1367,6 +1367,7 @@ export SOURCE_DATE_EPOCH=$(stat --printf='%Y' %{_specdir}/libvirt.spec)
            -Dapparmor_profiles=disabled \
            -Dsecdriver_apparmor=disabled \
            -Dudev=enabled \
+           -Djson_c=disabled \
            -Dyajl=enabled \
            %{?arg_sanlock} \
            -Dlibpcap=enabled \
@@ -1439,6 +1440,7 @@ export SOURCE_DATE_EPOCH=$(stat --printf='%Y' %{_specdir}/libvirt.spec)
   -Dfuse=disabled \
   -Dglusterfs=disabled \
   -Dhost_validate=disabled \
+  -Djson_c=disabled \
   -Dlibiscsi=disabled \
   -Dnbdkit=disabled \
   -Dnbdkit_config_default=disabled \

meson.build

@@ -1023,6 +1023,13 @@ glusterfs_dep = dependency('glusterfs-api', version: '>=' + glusterfs_version, r
 gnutls_version = '3.6.0'
 gnutls_dep = dependency('gnutls', version: '>=' + gnutls_version)
 
+json_c_version = '0.14'
+json_c_dep = dependency('json-c', version: '>=' + json_c_version, required: get_option('json_c'))
+if json_c_dep.found()
+  conf.set('WITH_JSON_C', 1)
+  conf.set('WITH_JSON', 1)
+endif
+
 # Check for BSD kvm (kernel memory interface)
 if host_machine.system() == 'freebsd'
   libkvm_dep = cc.find_library('kvm')
@@ -2342,6 +2349,7 @@ libs_summary = {
   'fuse': fuse_dep.found(),
   'glusterfs': glusterfs_dep.found(),
   'libbsd': libbsd_dep.found(),
+  'json-c': json_c_dep.found(),
   'libiscsi': libiscsi_dep.found(),
   'libkvm': libkvm_dep.found(),
   'libnbd': libnbd_dep.found(),

meson_options.txt

@@ -28,6 +28,7 @@ option('capng', type: 'feature', value: 'auto', description: 'cap-ng support')
 option('curl', type: 'feature', value: 'auto', description: 'curl support')
 option('fuse', type: 'feature', value: 'auto', description: 'fuse support')
 option('glusterfs', type: 'feature', value: 'auto', description: 'glusterfs support')
+option('json_c', type: 'feature', value: 'auto', description: 'JSON-C support')
 option('libiscsi', type: 'feature', value: 'auto', description: 'libiscsi support')
 option('libnl', type: 'feature', value: 'auto', description: 'libnl support')
 option('libpcap', type: 'feature', value: 'auto', description: 'libpcap support')