meson: use a convenience lib for curl-util.c

Previously we compiled curl-util.c at least two times, and then also
shared it using the extract+object. Let's build a static "convenience lib"
for it.

(Using extract+object everywhere is not possible because the different
places where it is used are conditionalized independently so we don't
have a single "source" that is always available.)

src/imds/meson.build

@@ -11,7 +11,8 @@ executables += [
                 'sources' : files(
                         'imdsd.c',
                         'imds-util.c'
-                ) + curl_util_c,
+                ),
+                'link_with' : [libcurlutil_static, libshared],
                 'dependencies' : [libcurl],
         },
         libexec_template + {

src/import/meson.build

@@ -33,8 +33,9 @@ executables += [
                         'pull-oci.c',
                         'pull-raw.c',
                         'pull-tar.c',
-                ) + curl_util_c,
+                ),
                 'objects' : ['systemd-importd'],
+                'link_with' : [libcurlutil_static, libshared],
                 'dependencies' : common_deps + [
                         libopenssl,
                 ],

src/shared/meson.build

@@ -256,9 +256,6 @@ if get_option('tests') != 'false'
         shared_sources += files('tests.c')
 endif
 
-# A small shared file that is is linked into a few places
-curl_util_c = files('curl-util.c')
-
 syscall_list_inc = custom_target(
         input : syscall_list_txt,
         output : 'syscall-list.inc',
@@ -458,3 +455,18 @@ libshared_fdisk = static_library(
                         userspace],
         c_args : ['-fvisibility=default'],
         build_by_default : false)
+
+# A small shared file that is linked into a few places.
+# It is not part of libshared because this code needs libcurl and
+# we don't want to link libshared to libcurl.
+if conf.get('HAVE_LIBCURL') == 1
+        libcurlutil_static = static_library(
+                'curl-util',
+                'curl-util.c',
+                implicit_include_directories : false,
+                dependencies : [userspace, libcurl],
+                include_directories : includes,
+                build_by_default : false)
+else
+        libcurlutil_static = []
+endif