Log error on failed underscores(), moving it to shared/

Move underscores() to shared/. It's the same as alias_normalize(), but
it rather operates in place, with the same string being passed.

The difference now that it's in shared/ is that it's a non-logging
function.

This makes us a little bit more verbose: we don't accept partially
correct module and aliases names in kcmdline and in configuration files.
We log an error instead.

2 files changed, 32 insertions, 0 deletions

diff --git a/shared/util.c b/shared/util.c
index 3902823..dac70ed 100644
--- a/shared/util.c
+++ b/shared/util.c
@@ -114,6 +114,37 @@ finish:
 	return 0;
 }
 
+/*
+ * Replace dashes with underscores.
+ * Dashes inside character range patterns (e.g. [0-9]) are left unchanged.
+ *
+ * For convenience, it returns error if @s is NULL
+ */
+int underscores(char *s)
+{
+	unsigned int i;
+
+	if (!s)
+		return -EINVAL;
+
+	for (i = 0; s[i]; i++) {
+		switch (s[i]) {
+		case '-':
+			s[i] = '_';
+			break;
+		case ']':
+			return -EINVAL;
+		case '[':
+			i += strcspn(&s[i], "]");
+			if (!s[i])
+				return -EINVAL;
+			break;
+		}
+	}
+
+	return 0;
+}
+
 char *modname_normalize(const char *modname, char buf[static PATH_MAX], size_t *len)
 {
 	size_t s;
diff --git a/shared/util.h b/shared/util.h
index ef3881a..e013d08 100644
--- a/shared/util.h
+++ b/shared/util.h
@@ -21,6 +21,7 @@ void *memdup(const void *p, size_t n) __attribute__((nonnull(1)));
 #define KMOD_EXTENSION_UNCOMPRESSED ".ko"
 
 int alias_normalize(const char *alias, char buf[static PATH_MAX], size_t *len) _must_check_ __attribute__((nonnull(1,2)));
+int underscores(char *s) _must_check_;
 char *modname_normalize(const char *modname, char buf[static PATH_MAX], size_t *len) __attribute__((nonnull(1, 2)));
 char *path_to_modname(const char *path, char buf[static PATH_MAX], size_t *len) __attribute__((nonnull(2)));
 bool path_ends_with_kmod_ext(const char *path, size_t len) __attribute__((nonnull(1)));