[glib: 1/2] gio/tests/{meson.build, pollable.c}: Determine libutil SONAME at build time

[Philip Withnall <pwithnall src gnome org>]

commit 373e46c2b2258b6a5476e099f452289b49b93ee5
Author: Iain Lane <iainl gnome org>
Date:   Tue Mar 2 13:15:50 2021 +0000

    gio/tests/{meson.build,pollable.c}: Determine libutil SONAME at build time
    
    Calling `dlopen()` with `libutil.so` makes the installed tests depend on
    having glibc's development files installed. To avoid this, we can work
    out the runtime library name at build time and `dlopen` that instead.
    
    This approach is [taken from libfprint][1], thanks to Marco Trevisan.
    
    [1]: https://gitlab.freedesktop.org/libfprint/fprintd/-/commit/f401f399a85dbeb2de165b9b9162eb552ab6eea7

 gio/tests/meson.build | 15 +++++++++++++++
 gio/tests/pollable.c  |  9 +++++----
 2 files changed, 20 insertions(+), 4 deletions(-)
---
diff --git a/gio/tests/meson.build b/gio/tests/meson.build
index 881f07ccc..a926ae01a 100644
--- a/gio/tests/meson.build
+++ b/gio/tests/meson.build
@@ -12,6 +12,21 @@ test_c_args = [
   '-UG_DISABLE_ASSERT',
 ]
 
+# workaround for https://github.com/mesonbuild/meson/issues/6880
+if build_machine.system() == 'linux'
+  libutil_name = 'libutil'
+  libutil = run_command('sh', '-c',
+    '''ldconfig -p | grep -o "[[:space:]]@0@\.so\(\.[0-9]\+\)\?\b"'''
+    .format(libutil_name)).stdout().strip().split('\n')
+
+  if libutil.length() > 0
+      message('Found libutil as @0@'.format(libutil[0]))
+      test_c_args += '-DLIBUTIL_SONAME="@0@"'.format(libutil[0])
+  else
+      warning('libutil not found')
+  endif # libutil.length() > 0
+endif # build_machine.system() == 'linux'
+
 if host_machine.system() == 'windows'
   common_gio_tests_deps += [iphlpapi_dep, winsock2, cc.find_library ('secur32')]
 endif
diff --git a/gio/tests/pollable.c b/gio/tests/pollable.c
index d57c4733a..516d7f4e4 100644
--- a/gio/tests/pollable.c
+++ b/gio/tests/pollable.c
@@ -187,14 +187,15 @@ test_pollable_unix_pty (void)
 {
   int (*openpty_impl) (int *, int *, char *, void *, void *);
   int a, b, status;
-#ifdef __linux__
+#ifdef LIBUTIL_SONAME
   void *handle;
 #endif
 
   g_test_summary ("Test that PTYs are considered pollable");
 
-#ifdef __linux__
-  handle = dlopen ("libutil.so", RTLD_GLOBAL | RTLD_LAZY);
+#ifdef LIBUTIL_SONAME
+  handle = dlopen (LIBUTIL_SONAME, RTLD_GLOBAL | RTLD_LAZY);
+  g_assert_nonnull (handle);
 #endif
 
   openpty_impl = dlsym (RTLD_DEFAULT, "openpty");
@@ -223,7 +224,7 @@ test_pollable_unix_pty (void)
   close (b);
 
 close_libutil:
-#ifdef __linux__
+#ifdef LIBUTIL_SONAME
   dlclose (handle);
 #else
   return;