meson: optionally build seccomp if it supports notify

Signed-off-by: Peter Hunt <[email protected]>

hack/seccomp-notify.sh

@@ -1,4 +1,8 @@
 #!/bin/bash
-if $(printf '#include <linux/seccomp.h>\nvoid main(){struct seccomp_notif_sizes s;}' | cc -x c - -o /dev/null 2> /dev/null && pkg-config --atleast-version 2.5.0 libseccomp); then
-        echo "0"
+CC=${CC:-cc}
+PKG_CONFIG=${PKG_CONFIG:-pkg-config}
+if $(printf '#include <linux/seccomp.h>\nvoid main(){struct seccomp_notif_sizes s;}' | $CC -x c - -o /dev/null 2> /dev/null && $PKG_CONFIG --atleast-version 2.5.0 libseccomp); then
+	echo "0"
+	exit 0
 fi
+exit 1

meson.build

@@ -45,12 +45,17 @@ endif
 
 sd_journal = dependency('libsystemd-journal', required : false)
 if not sd_journal.found()
-	sd_journal = dependency('libsystemd', required : false)
+  sd_journal = dependency('libsystemd', required : false)
 endif
 if sd_journal.found()
 	add_project_arguments('-DUSE_JOURNALD=1', language : 'c')
 endif
 
+seccomp = dependency('libseccomp', required : false)
+if seccomp.found() and compiler.sizeof('seccomp_notif_sizes', prefix : '#include <linux/seccomp.h>') > 0
+  add_project_arguments('-DUSE_SECCOMP=1', language : 'c')
+endif
+
 executable('conmon',
            ['src/conmon.c',
             'src/config.h',
@@ -86,7 +91,7 @@ executable('conmon',
             'src/utils.h',
             'src/seccomp_notify.c',
             'src/seccomp_notify.h'],
-           dependencies : [glib, libdl, sd_journal],
+           dependencies : [glib, libdl, sd_journal, seccomp],
            install : true,
            install_dir : join_paths(get_option('libexecdir'), 'podman'),
 )