soup: Re-enable libsoup dlopen on macOS

Move from GModule to libdl for loading libraries on all platforms.
This is necessary due to a macOS bug where dyld uses the incorrect
@loader_path value for RPATH entries, and fails to find libsoup.

More details here: https://gitlab.freedesktop.org/gstreamer/gstreamer/-/issues/1171#note_2290789

Fixes https://gitlab.freedesktop.org/gstreamer/gstreamer/-/issues/3792

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/7635>

subprojects/gst-plugins-good/ext/adaptivedemux2/meson.build

@@ -56,13 +56,19 @@ hls_dep = dependency('', required : false)
 adaptivedemux2_dep = dependency('', required : false)
 
 adaptivedemux2_opt = get_option('adaptivedemux2')
-soup_opt = get_option('soup')
-soup_ver_opt = get_option('soup-version')
 if adaptivedemux2_opt.disabled()
   message('Not building adaptivedemux2 plugin because it was disabled')
   subdir_done()
 endif
 
+if soup_lookup_dep and not libsoup3_dep.found() and not libsoup2_dep.found()
+  if adaptivedemux2_opt.enabled()
+    error(f'adaptivedemux2: Either libsoup2 or libsoup3 is needed')
+  endif
+  message(f'Not building adaptivedemux2: must link to either libsoup2 or libsoup3')
+  subdir_done()
+endif
+
 adaptive_xml2_dep = dependency('libxml-2.0', version : '>= 2.8', allow_fallback: true, required: adaptivedemux2_opt)
 
 if not adaptive_xml2_dep.found()
@@ -78,35 +84,6 @@ plugin_sources += hls_sources
 
 libdl = cc.find_library('dl', required: false)
 soup_loader_args = ['-DBUILDING_ADAPTIVEDEMUX2']
-soup_link_args = []
-soup_link_deps = []
-
-default_library = get_option('default_library')
-if host_system != 'linux' or default_library in ['static', 'both']
-  if soup_ver_opt in ['auto', '3']
-    libsoup3_dep = dependency('libsoup-3.0', allow_fallback: true,
-                              required: soup_ver_opt == '3' and soup_opt.enabled())
-  endif
-  if soup_ver_opt in ['auto', '2']
-    libsoup2_dep = dependency('libsoup-2.4', version : '>=2.48', allow_fallback: true,
-                              default_options: ['sysprof=disabled'],
-                              required: soup_ver_opt == '2' and soup_opt.enabled())
-  endif
-
-  if libsoup3_dep.found()
-    soup_link_deps += [libsoup3_dep]
-    soup_link_args = ['-DLINK_SOUP=3']
-  elif libsoup2_dep.found()
-    soup_link_deps += [libsoup2_dep]
-    soup_link_args = ['-DLINK_SOUP=2']
-  else
-    if adaptivedemux2_opt.enabled()
-      error(f'adaptivedemux2: Either libsoup2 or libsoup3 is needed')
-    endif
-    message(f'Not building adaptivedemux2 plugin: either libsoup2 or libsoup3 is needed')
-    subdir_done()
-  endif
-endif
 
 # Shared plugin doesn't link to libsoup but dlopen()s it at runtime
 adaptive_kwargs = {
@@ -120,26 +97,27 @@ adaptive_deps = [gmodule_dep, gst_dep, gsttag_dep, gstnet_dep, gstbase_dep, gstp
 adaptive_args = [gst_plugins_good_args, soup_loader_args, hls_cargs,
     '-DGST_ISOFF_API=G_GNUC_INTERNAL']
 
-if host_system != 'linux'
-    adaptivedemux2 = library('gstadaptivedemux2',
-      c_args: [adaptive_args, soup_link_args],
-      dependencies: [adaptive_deps, soup_link_deps],
-      kwargs: adaptive_kwargs)
-    adaptivedemux2_static = adaptivedemux2
-    adaptivedemux2_shared = adaptivedemux2
+if host_system == 'windows'
+  assert(soup_linked_target)
+  adaptivedemux2 = library('gstadaptivedemux2',
+    c_args: [adaptive_args, soup_linked_target_args],
+    dependencies: [adaptive_deps, soup_linked_target_deps],
+    kwargs: adaptive_kwargs)
+  adaptivedemux2_static = adaptivedemux2
+  adaptivedemux2_shared = adaptivedemux2
 else
   if default_library in ['static', 'both']
     # Static plugin links to libsoup directly at build time
     adaptivedemux2_static = static_library('gstadaptivedemux2',
-      c_args: [adaptive_args, soup_link_args],
-      dependencies: [adaptive_deps, soup_link_deps],
+      c_args: [adaptive_args, soup_linked_target_args],
+      dependencies: [adaptive_deps, soup_linked_target_deps],
       kwargs: adaptive_kwargs)
   endif
   if default_library in ['shared', 'both']
     adaptivedemux2_shared = shared_library('gstadaptivedemux2',
       c_args: adaptive_args,
       dependencies: adaptive_deps,
-      kwargs: adaptive_kwargs)
+      kwargs: adaptive_kwargs + soup_dlopen_target_kwargs)
   endif
 endif
 

subprojects/gst-plugins-good/ext/meson.build

@@ -1,3 +1,59 @@
+# We need libsoup for the soup plugin and for adaptivedemux2, and we can link
+# to either libsoup-2.4 or libsoup-3.0. There's a few cases here:
+#
+# 1. Windows, where we do not support dlopen()
+# 2. UNIX, and we build only a shared library
+# 3. UNIX, and we build only a static library
+# 4. UNIX, and we build both (static and shared)
+#
+# In cases 1,2,3: we look up the dependency
+# In case 1: we create one library() target that always links to libsoup
+# In cases 3,4: we create one static_library() target that links to libsoup
+# In cases 2,4: we create one shared_library() target that dlopen()s libsoup
+
+libsoup2_dep = disabler()
+libsoup3_dep = disabler()
+soup_ver_opt = get_option('soup-version')
+
+default_library = get_option('default_library')
+soup_linked_target = host_system == 'windows' or default_library != 'shared'
+soup_lookup_dep = get_option('soup-lookup-dep') or soup_linked_target
+if soup_ver_opt in ['auto', '3']
+  libsoup3_dep = dependency('libsoup-3.0', allow_fallback: true,
+                            required: soup_ver_opt == '3' and soup_lookup_dep)
+endif
+if soup_ver_opt in ['auto', '2']
+  libsoup2_dep = dependency('libsoup-2.4', version : '>=2.48', allow_fallback: true,
+                            default_options: ['sysprof=disabled'],
+                            required: soup_ver_opt == '2' and soup_lookup_dep)
+endif
+
+if soup_linked_target
+  if libsoup3_dep.found()
+    soup_linked_target_deps = [libsoup3_dep]
+    soup_linked_target_args = ['-DLINK_SOUP=3']
+    message('soup and adaptivedemux2 plugins: linking to libsoup-3.0')
+  elif libsoup2_dep.found()
+    soup_linked_target_deps = [libsoup2_dep]
+    soup_linked_target_args = ['-DLINK_SOUP=2']
+    message('soup and adaptivedemux2 plugins: linking to libsoup-2.4')
+  endif
+endif
+
+# Hack to set the right RPATH for making dlopen() work inside the devenv on
+# macOS when using libsoup as a subproject.
+soup_dlopen_target_kwargs = {}
+if host_system == 'darwin'
+  foreach dep : [libsoup3_dep, libsoup2_dep]
+    if dep.found() and dep.type_name() == 'internal'
+      soup_dlopen_target_kwargs += {
+        'build_rpath': '@loader_path/../../../libsoup-' + dep.version() / 'libsoup',
+      }
+      break
+    endif
+  endforeach
+endif
+
 subdir('aalib')
 subdir('adaptivedemux2')
 subdir('amrnb')

subprojects/gst-plugins-good/ext/soup/gstsouploader.c

@@ -34,26 +34,36 @@ GST_DEBUG_CATEGORY (gst_soup_debug);
 
 #ifndef LINK_SOUP
 
-#if defined(__APPLE__) || defined(G_OS_WIN32)
-#error "dlopen of libsoup is only supported on Linux"
+#if !defined(G_OS_UNIX)
+#error "dlopen of libsoup is only supported on UNIX"
 #endif
 
+#ifdef __APPLE__
+#define LIBSOUP_3_SONAME "libsoup-3.0.0.dylib"
+#define LIBSOUP_2_SONAME "libsoup-2.4.1.dylib"
+#else
 #define LIBSOUP_3_SONAME "libsoup-3.0.so.0"
 #define LIBSOUP_2_SONAME "libsoup-2.4.so.1"
+#endif
 
 #define LOAD_SYMBOL(name) G_STMT_START {                                \
-    if (!g_module_symbol (module, G_STRINGIFY (name), (gpointer *) &G_PASTE (vtable->_, name))) { \
-      GST_ERROR ("Failed to load '%s' from %s, %s", G_STRINGIFY (name), g_module_name (module), g_module_error()); \
+    gpointer sym = NULL;                                                \
+    if (!(sym = dlsym (handle, G_STRINGIFY (name)))) {                  \
+      GST_ERROR ("Failed to load '%s' from %s, %s", G_STRINGIFY (name), \
+          libsoup_sonames[i], dlerror());                               \
       goto error;                                                       \
     }                                                                   \
+    G_PASTE (vtable->_, name) = sym;                                    \
   } G_STMT_END;
 
-#define LOAD_VERSIONED_SYMBOL(version, name) G_STMT_START {             \
-  if (!g_module_symbol(module, G_STRINGIFY(name), (gpointer *)&G_PASTE(vtable->_, G_PASTE(name, G_PASTE(_, version))))) { \
-    GST_WARNING ("Failed to load '%s' from %s, %s", G_STRINGIFY(name),  \
-                g_module_name(module), g_module_error());               \
-    goto error;                                                         \
-  }                                                                     \
+#define LOAD_VERSIONED_SYMBOL(version, name) G_STMT_START {               \
+    gpointer sym = NULL;                                                  \
+    if (!(sym = dlsym(handle, G_STRINGIFY(name)))) {                      \
+      GST_WARNING ("Failed to load '%s' from %s, %s", G_STRINGIFY(name),  \
+                   libsoup_sonames[i], dlerror());                        \
+      goto error;                                                         \
+    }                                                                     \
+    G_PASTE(vtable->_, G_PASTE(name, G_PASTE(_, version))) = sym;         \
   } G_STMT_END;
 
 typedef struct _GstSoupVTable
@@ -136,19 +146,18 @@ typedef struct _GstSoupVTable
 
 static GstSoupVTable gst_soup_vtable = { 0, };
 
+#define SOUP_NAMES 2
+
 gboolean
 gst_soup_load_library (void)
 {
-  GModule *module;
   GstSoupVTable *vtable;
-  const gchar *libsoup_sonames[5] = { 0 };
-  guint len = 0;
+  const char *libsoup_sonames[SOUP_NAMES + 1] = { 0 };
+  gpointer handle = NULL;
 
   if (gst_soup_vtable.loaded)
     return TRUE;
 
-  g_assert (g_module_supported ());
-
 #ifdef BUILDING_ADAPTIVEDEMUX2
   GST_DEBUG_CATEGORY_INIT (gst_adaptivedemux_soup_debug, "adaptivedemux2-soup",
       0, "adaptivedemux2-soup");
@@ -158,8 +167,6 @@ gst_soup_load_library (void)
 
 #ifdef HAVE_RTLD_NOLOAD
   {
-    gpointer handle = NULL;
-
     /* In order to avoid causing conflicts we detect if libsoup 2 or 3 is loaded already.
      * If so use that. Otherwise we will try to load our own version to use preferring 3. */
 
@@ -183,14 +190,12 @@ gst_soup_load_library (void)
 #endif /* HAVE_RTLD_NOLOAD */
 
   vtable = &gst_soup_vtable;
-  len = g_strv_length ((gchar **) libsoup_sonames);
 
-  for (guint i = 0; i < len; i++) {
-    module =
-        g_module_open (libsoup_sonames[i],
-        G_MODULE_BIND_LAZY | G_MODULE_BIND_LOCAL);
-    if (module) {
-      GST_DEBUG ("Loaded %s", g_module_name (module));
+  for (guint i = 0; i < SOUP_NAMES; i++) {
+    if (!handle)
+      handle = dlopen (libsoup_sonames[i], RTLD_NOW | RTLD_GLOBAL);
+    if (handle) {
+      GST_DEBUG ("Loaded %s", libsoup_sonames[i]);
       if (g_strstr_len (libsoup_sonames[i], -1, "soup-2")) {
         vtable->lib_version = 2;
         LOAD_VERSIONED_SYMBOL (2, soup_logger_new);
@@ -251,7 +256,7 @@ gst_soup_load_library (void)
 
     error:
       GST_DEBUG ("Failed to find all libsoup symbols");
-      g_clear_pointer (&module, g_module_close);
+      g_clear_pointer (&handle, dlclose);
       continue;
     } else {
       GST_DEBUG ("Module %s not found", libsoup_sonames[i]);

subprojects/gst-plugins-good/ext/soup/meson.build

@@ -13,43 +13,16 @@ if soup_opt.disabled()
   subdir_done()
 endif
 
+if soup_lookup_dep and not libsoup3_dep.found() and not libsoup2_dep.found()
+  if soup_opt.enabled()
+    error(f'soup: Either libsoup2 or libsoup3 is needed')
+  endif
+  message(f'Not building soup plugin: must link to either libsoup2 or libsoup3')
+  subdir_done()
+endif
+
 libdl_dep = cc.find_library('dl', required: false)
 
-soup_link_args = []
-soup_link_deps = []
-libsoup2_dep = disabler()
-libsoup3_dep = disabler()
-default_library = get_option('default_library')
-soup_lookup_dep = get_option('soup-lookup-dep') and host_system == 'linux'
-if host_system != 'linux' or default_library in ['static', 'both'] or soup_lookup_dep
-  if soup_ver_opt in ['auto', '3']
-    libsoup3_dep = dependency('libsoup-3.0', allow_fallback: true,
-                              required: soup_ver_opt == '3' and soup_opt.enabled())
-  endif
-  if soup_ver_opt in ['auto', '2']
-    libsoup2_dep = dependency('libsoup-2.4', version : '>=2.48', allow_fallback: true,
-                              default_options: ['sysprof=disabled'],
-                              required: soup_ver_opt == '2' and soup_opt.enabled())
-  endif
-endif
-
-if host_system != 'linux' or default_library in ['static', 'both']
-  if libsoup3_dep.found()
-    soup_link_deps += libsoup3_dep
-    soup_link_args += '-DLINK_SOUP=3'
-    message('soup plugin: linking to libsoup-3.0')
-  elif libsoup2_dep.found()
-    soup_link_deps += libsoup2_dep
-    soup_link_args += '-DLINK_SOUP=2'
-    message('soup plugin: linking to libsoup-2.4')
-  else
-    if soup_opt.enabled()
-      error('Either libsoup2 or libsoup3 is needed')
-    endif
-    subdir_done()
-  endif
-endif
-
 soup_library_kwargs = {
   'sources' : soup_sources,
   'link_args' : noseh_link_args,
@@ -60,19 +33,21 @@ soup_library_kwargs = {
 soup_library_deps = [gst_dep, gstbase_dep, gsttag_dep, gmodule_dep, gio_dep, libdl_dep]
 soup_library_c_args = gst_plugins_good_args
 
-if host_system != 'linux'
+if host_system == 'windows'
+  assert(soup_linked_target)
   gstsouphttpsrc = library('gstsoup',
-    c_args : soup_library_c_args + soup_link_args,
-    dependencies : soup_library_deps + soup_link_deps,
+    c_args : soup_library_c_args + soup_linked_target_args,
+    dependencies : soup_library_deps + soup_linked_target_deps,
     kwargs: soup_library_kwargs,
   )
   gstsouphttpsrc_shared = gstsouphttpsrc
   gstsouphttpsrc_static = gstsouphttpsrc
 else
   if default_library in ['static', 'both']
+    assert(soup_linked_target)
     gstsouphttpsrc_static = static_library('gstsoup',
-      c_args : soup_library_c_args + soup_link_args,
-      dependencies : soup_library_deps + soup_link_deps,
+      c_args : soup_library_c_args + soup_linked_target_args,
+      dependencies : soup_library_deps + soup_linked_target_deps,
       kwargs: soup_library_kwargs,
     )
   endif
@@ -80,7 +55,7 @@ else
     gstsouphttpsrc_shared = shared_library('gstsoup',
       c_args : soup_library_c_args,
       dependencies : soup_library_deps,
-      kwargs: soup_library_kwargs,
+      kwargs: soup_library_kwargs + soup_dlopen_target_kwargs,
     )
   endif
 endif