Move module-util.h to src/shared/ and load_module() to libshared

Unfortunately this needs libshared to link to libkmod. Before it was linked
into systemd-udevd, udevadm, and systemd each seperately. On most systems this
doesn't make much difference, because at least systemd would be installed, but
it might not be in small chroots. It is a small library, so I hope this is not
a big issue.

1 files changed, 64 insertions, 0 deletions

diff --git a/src/shared/module-util.c b/src/shared/module-util.c
new file mode 100644
index 0000000000..36f4f364c1
--- /dev/null
+++ b/src/shared/module-util.c
@@ -0,0 +1,64 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+
+#include <errno.h>
+
+#include "module-util.h"
+
+int module_load_and_warn(struct kmod_ctx *ctx, const char *module) {
+        const int probe_flags = KMOD_PROBE_APPLY_BLACKLIST;
+        struct kmod_list *itr;
+        _cleanup_(kmod_module_unref_listp) struct kmod_list *modlist = NULL;
+        int r = 0;
+
+        log_debug("Loading module: %s", module);
+
+        r = kmod_module_new_from_lookup(ctx, module, &modlist);
+        if (r < 0)
+                return log_error_errno(r, "Failed to lookup module alias '%s': %m", module);
+
+        if (!modlist) {
+                log_error("Failed to find module '%s'", module);
+                return -ENOENT;
+        }
+
+        kmod_list_foreach(itr, modlist) {
+                _cleanup_(kmod_module_unrefp) struct kmod_module *mod = NULL;
+                int state, err;
+
+                mod = kmod_module_get_module(itr);
+                state = kmod_module_get_initstate(mod);
+
+                switch (state) {
+                case KMOD_MODULE_BUILTIN:
+                        log_info("Module '%s' is builtin", kmod_module_get_name(mod));
+                        break;
+
+                case KMOD_MODULE_LIVE:
+                        log_debug("Module '%s' is already loaded", kmod_module_get_name(mod));
+                        break;
+
+                default:
+                        err = kmod_module_probe_insert_module(mod, probe_flags,
+                                                              NULL, NULL, NULL, NULL);
+
+                        if (err == 0)
+                                log_info("Inserted module '%s'", kmod_module_get_name(mod));
+                        else if (err == KMOD_PROBE_APPLY_BLACKLIST)
+                                log_info("Module '%s' is blacklisted", kmod_module_get_name(mod));
+                        else {
+                                assert(err < 0);
+
+                                log_full_errno(err == ENODEV ? LOG_NOTICE :
+                                               err == ENOENT ? LOG_WARNING :
+                                                               LOG_ERR,
+                                               err,
+                                               "Failed to insert module '%s': %m",
+                                               kmod_module_get_name(mod));
+                                if (!IN_SET(err, ENODEV, ENOENT))
+                                        r = err;
+                        }
+                }
+        }
+
+        return r;
+}