log: add an "error" parameter to all low-level logging calls and intrdouce log_error_errno() as log calls that take error numbers

This change has two benefits:

- The format string %m will now resolve to the specified error (or to
  errno if the specified error is 0. This allows getting rid of a ton of
  strerror() invocations, a function that is not thread-safe.

- The specified error can be passed to the journal in the ERRNO= field.

Now of course, we just need somebody to convert all cases of this:

        log_error("Something happened: %s", strerror(-r));

into thus:

        log_error_errno(-r, "Something happened: %m");

1 files changed, 11 insertions, 13 deletions

diff --git a/src/udev/udev-builtin-kmod.c b/src/udev/udev-builtin-kmod.c
index 66807b381b..f3d164763d 100644
--- a/src/udev/udev-builtin-kmod.c
+++ b/src/udev/udev-builtin-kmod.c
@@ -31,7 +31,7 @@
 
 #include "udev.h"
 
-static struct kmod_ctx *ctx;
+static struct kmod_ctx *ctx = NULL;
 
 static int load_module(struct udev *udev, const char *alias) {
         struct kmod_list *list = NULL;
@@ -43,18 +43,18 @@ static int load_module(struct udev *udev, const char *alias) {
                 return err;
 
         if (list == NULL)
-                log_debug("no module matches '%s'", alias);
+                log_debug("No module matches '%s'", alias);
 
         kmod_list_foreach(l, list) {
                 struct kmod_module *mod = kmod_module_get_module(l);
 
                 err = kmod_module_probe_insert_module(mod, KMOD_PROBE_APPLY_BLACKLIST, NULL, NULL, NULL, NULL);
                 if (err == KMOD_PROBE_APPLY_BLACKLIST)
-                        log_debug("module '%s' is blacklisted", kmod_module_get_name(mod));
+                        log_debug("Module '%s' is blacklisted", kmod_module_get_name(mod));
                 else if (err == 0)
-                        log_debug("inserted '%s'", kmod_module_get_name(mod));
+                        log_debug("Inserted '%s'", kmod_module_get_name(mod));
                 else
-                        log_debug("failed to insert '%s'", kmod_module_get_name(mod));
+                        log_debug("Failed to insert '%s'", kmod_module_get_name(mod));
 
                 kmod_module_unref(mod);
         }
@@ -63,10 +63,8 @@ static int load_module(struct udev *udev, const char *alias) {
         return err;
 }
 
-_printf_(6,0)
-static void udev_kmod_log(void *data, int priority, const char *file, int line,
-                          const char *fn, const char *format, va_list args) {
-        log_metav(priority, file, line, fn, format, args);
+_printf_(6,0) static void udev_kmod_log(void *data, int priority, const char *file, int line, const char *fn, const char *format, va_list args) {
+        log_metav(priority, 0, file, line, fn, format, args);
 }
 
 static int builtin_kmod(struct udev_device *dev, int argc, char *argv[], bool test) {
@@ -82,7 +80,7 @@ static int builtin_kmod(struct udev_device *dev, int argc, char *argv[], bool te
         }
 
         for (i = 2; argv[i]; i++) {
-                log_debug("execute '%s' '%s'", argv[1], argv[i]);
+                log_debug("Execute '%s' '%s'", argv[1], argv[i]);
                 load_module(udev, argv[i]);
         }
 
@@ -98,7 +96,7 @@ static int builtin_kmod_init(struct udev *udev) {
         if (!ctx)
                 return -ENOMEM;
 
-        log_debug("load module index");
+        log_debug("Load module index");
         kmod_set_log_fn(ctx, udev_kmod_log, udev);
         kmod_load_resources(ctx);
         return 0;
@@ -106,13 +104,13 @@ static int builtin_kmod_init(struct udev *udev) {
 
 /* called on udev shutdown and reload request */
 static void builtin_kmod_exit(struct udev *udev) {
-        log_debug("unload module index");
+        log_debug("Unload module index");
         ctx = kmod_unref(ctx);
 }
 
 /* called every couple of seconds during event activity; 'true' if config has changed */
 static bool builtin_kmod_validate(struct udev *udev) {
-        log_debug("validate module index");
+        log_debug("Validate module index");
         if (!ctx)
                 return false;
         return (kmod_validate_resources(ctx) != KMOD_RESOURCES_OK);