TOD: Add TOuch Drivers loader

libfprint/fp-context.c

@@ -24,6 +24,11 @@
 #include "fpi-device.h"
 #include <gusb.h>
 
+#include <config.h>
+#ifdef HAVE_LIBFPRINT_TOD
+#include "tod/tod-shared-loader.h"
+#endif
+
 /**
  * SECTION: fp-context
  * @title: FpContext
@@ -215,6 +220,8 @@ fp_context_finalize (GObject *object)
   g_object_run_dispose (G_OBJECT (priv->usb_ctx));
   g_clear_object (&priv->usb_ctx);
 
+  fpi_tod_shared_drivers_unregister ();
+
   G_OBJECT_CLASS (fp_context_parent_class)->finalize (object);
 }
 
@@ -266,11 +273,16 @@ static void
 fp_context_init (FpContext *self)
 {
   g_autoptr(GError) error = NULL;
+  g_autoptr(GArray) shared_drivers = NULL;
   FpContextPrivate *priv = fp_context_get_instance_private (self);
   guint i;
 
   priv->drivers = fpi_get_driver_types ();
 
+  fpi_tod_shared_drivers_register ();
+  shared_drivers = fpi_tod_shared_drivers_get ();
+  g_array_prepend_vals (priv->drivers, shared_drivers->data, shared_drivers->len);
+
   if (get_drivers_whitelist_env ())
     {
       for (i = 0; i < priv->drivers->len;)

libfprint/meson.build

@@ -234,6 +234,10 @@ libfprint_private = static_library('fprint-private',
     link_with: libnbis,
     install: false)
 
+if get_option('tod')
+    subdir('tod')
+endif
+
 libfprint_drivers = static_library('fprint-drivers',
     sources: drivers_sources,
     c_args: drivers_cflags,

libfprint/tod/libfprint-tod.ver

@@ -0,0 +1,6 @@
+LIBFPRINT_TOD_1.0.0 {
+global:
+	fpi_*;
+local:
+    *;
+};

libfprint/tod/meson.build

@@ -0,0 +1,89 @@
+tod_soversion = 1
+tod_version = '@0@.0'.format(tod_soversion)
+tod_versioned_path = '-'.join(tod_version.split('.'))
+tod_subpath = meson.project_name() / 'tod-@0@'.format(tod_versioned_path)
+tod_modules_prefix = get_option('libdir') / tod_subpath
+
+tod_conf = configuration_data()
+tod_conf.set_quoted('TOD_DRIVERS_DIR',
+    get_option('prefix') / get_option('libdir') / tod_subpath)
+configure_file(output: 'tod-config.h', configuration: tod_conf)
+
+gmodule_dep = dependency('gmodule-2.0', version: '>=' + glib_min_version)
+deps += gmodule_dep
+
+mapfile = files('libfprint-tod.ver')
+
+libfprint_tod_private = static_library('fprint-tod-private',
+    sources: [
+        'tod-shared-loader.c',
+    ],
+    include_directories: include_directories('..'),
+    link_with: libfprint_private,
+    dependencies: deps,
+    install: false,
+)
+
+tod_sources = []
+foreach source: libfprint_private_sources
+    tod_sources += '..' / source
+endforeach
+
+libfprint_tod = library('fprint-tod',
+    sources: [
+        tod_sources,
+    ],
+    soversion: (soversion * 100) + tod_soversion,
+    include_directories: include_directories('..'),
+    version: '@0@.'.format(soversion) + tod_version,
+    link_args: [
+        '-Wl,--version-script,@0@/@1@'.format(meson.source_root(), mapfile[0]),
+        '-Wl,--unresolved-symbols=ignore-in-object-files'
+    ],
+    link_depends: mapfile,
+    link_with: [libfprint_private],
+    dependencies: deps,
+    install: true)
+
+deps += declare_dependency(
+    link_with: [
+        libfprint_tod,
+        libfprint_tod_private,
+    ]
+)
+
+pkgconfig = import('pkgconfig')
+pkgconfig.generate(libfprint_tod,
+    name: 'libfprint-tod',
+    filebase: 'libfprint@0@-tod-@1@'.format(soversion, tod_versioned_path),
+    description: 'Private Libfprint Touch Drivers API',
+    version: meson.project_version() + '.@0@'.format(tod_version),
+    subdirs: tod_subpath,
+    requires_private: [
+        meson.project_name() + '@0@'.format(soversion),
+    ],
+    variables: [
+        'tod_driversdir=${libdir}/@0@'.format(tod_subpath)
+    ]
+)
+
+tod_headers = []
+extra_libfprint_headers = [
+    'drivers_api.h',
+]
+
+foreach header: libfprint_private_headers + extra_libfprint_headers
+    tod_headers += '..' / header
+endforeach
+
+custom_target('tod_fpi_enums_headers',
+  depends: fpi_enums,
+  input: fpi_enums_h,
+  output: 'fpi-enums.h',
+  command: ['cp', '@INPUT@', '-v', '@OUTPUT@'],
+  install: true,
+  install_dir: get_option('includedir') / tod_subpath)
+
+install_headers(tod_headers,
+    subdir: tod_subpath
+)

libfprint/tod/tod-shared-loader.c

@@ -0,0 +1,148 @@
+/*
+ * Shared library loader for libfprint
+ * Copyright (C) 2019 Marco Trevisan <marco.trevisan@canonical.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#define FP_COMPONENT "tod"
+
+#include <gmodule.h>
+
+#include "tod-shared-loader.h"
+#include "fpi-device.h"
+#include "fpi-log.h"
+#include "tod-config.h"
+
+#define FPI_TOD_ENTRY_GTYPE_GETTER "fpi_tod_shared_driver_get_type"
+
+static GArray *shared_drivers = NULL;
+static GList *shared_modules = NULL;
+
+typedef GModule FpiTodModule;
+typedef GType (*FpiTodShardDriverTypeGetter) (void);
+
+G_DEFINE_AUTOPTR_CLEANUP_FUNC (FpiTodModule, g_module_close);
+
+static const char *
+get_tod_drivers_dir (void)
+{
+  const char *tod_env_path = g_getenv ("FP_TOD_DRIVERS_DIR");
+
+  if (!tod_env_path || *tod_env_path == '\0')
+    return TOD_DRIVERS_DIR;
+
+  return tod_env_path;
+}
+
+void
+fpi_tod_shared_drivers_register (void)
+{
+  const char *dirname;
+  const char *basename;
+
+  g_autoptr(GError) error = NULL;
+  g_autoptr(GDir) dir = NULL;
+  gpointer symbol;
+
+  g_assert_null (shared_drivers);
+
+  dirname = get_tod_drivers_dir ();
+  dir = g_dir_open (dirname, 0, &error);
+
+  shared_drivers = g_array_new (TRUE, FALSE, sizeof (GType));
+
+  if (error)
+    {
+      fp_dbg ("Impossible to load the shared drivers dir %s", error->message);
+      return;
+    }
+
+  while ((basename = g_dir_read_name (dir)) != NULL)
+    {
+      g_autoptr(FpiTodModule) module = NULL;
+      g_autoptr(GTypeClass) type_class = NULL;
+      g_autofree char *module_path = NULL;
+      FpiTodShardDriverTypeGetter type_getter;
+      FpDeviceClass *cls;
+      GType driver;
+
+      if (!g_str_has_suffix (basename, ".so"))
+        continue;
+
+      module_path = g_build_filename (dirname, basename, NULL);
+
+      if (!g_file_test (module_path, G_FILE_TEST_IS_REGULAR))
+        continue;
+
+      fp_dbg ("Opening driver %s", module_path);
+
+      module = g_module_open (module_path, G_MODULE_BIND_LAZY | G_MODULE_BIND_LOCAL);
+
+      if (!module)
+        {
+          fp_err ("Impossible to load module %s: %s", module_path,
+                  g_module_error ());
+          continue;
+        }
+
+      if (!g_module_symbol (module, FPI_TOD_ENTRY_GTYPE_GETTER, &symbol))
+        {
+          fp_err ("Library %s doesn't expose the required entry point symbol",
+                  module_path);
+          continue;
+        }
+
+      type_getter = symbol;
+      driver = type_getter ();
+      fp_dbg ("Found TOD entry point symbol %p, GType is %lu", symbol, driver);
+
+      if (!G_TYPE_IS_OBJECT (driver) || !g_type_is_a (driver, FP_TYPE_DEVICE))
+        {
+          fp_err ("Library %s returned GType (%lu) doesn't represent a device",
+                  module_path, driver);
+          continue;
+        }
+
+      type_class = g_type_class_ref (driver);
+      g_assert_true (g_type_check_class_is_a (type_class, FP_TYPE_DEVICE));
+
+      cls = FP_DEVICE_CLASS (type_class);
+
+      fp_dbg ("Loading driver %s (%s)", cls->id, cls->full_name);
+      g_array_append_val (shared_drivers, driver);
+
+      shared_modules = g_list_prepend (shared_modules,
+                                       g_steal_pointer (&module));
+    }
+}
+
+void
+fpi_tod_shared_drivers_unregister (void)
+{
+  g_clear_pointer (&shared_drivers, g_array_unref);
+
+  if (g_strcmp0 (g_getenv ("FP_TOD_KEEP_MODULES_OPEN"), "TRUE") != 0)
+    {
+      g_list_free_full (shared_modules, (GDestroyNotify) g_module_close);
+      shared_modules = NULL;
+    }
+}
+
+GArray *
+fpi_tod_shared_drivers_get (void)
+{
+  return g_array_ref (shared_drivers);
+}

libfprint/tod/tod-shared-loader.h

@@ -0,0 +1,28 @@
+/*
+ * Shared library loader for libfprint
+ * Copyright (C) 2019 Marco Trevisan <marco.trevisan@canonical.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#pragma once
+
+#include <glib.h>
+
+
+void fpi_tod_shared_drivers_register (void);
+void fpi_tod_shared_drivers_unregister (void);
+
+GArray *fpi_tod_shared_drivers_get (void);

meson.build

@@ -187,6 +187,8 @@ if get_option('gtk-examples')
     endif
 endif
 
+libfprint_conf.set10('HAVE_LIBFPRINT_TOD', get_option('tod'))
+
 configure_file(output: 'config.h', configuration: libfprint_conf)
 
 subdir('libfprint')

meson_options.txt

@@ -22,3 +22,8 @@ option('doc',
        description: 'Whether to build the API documentation',
        type: 'boolean',
        value: true)
+
+option('tod',
+       description: 'Whether to build the TOD library',
+       type: 'boolean',
+       value: true)