[RFC PATCH v2 2/3] lib/string: move sysfs string functions out of string.c

[Christophe Leroy <christophe.leroy@c-s.fr>]

In order to implement interceptors for string functions, move
higher level sysfs related string functions out of string.c

This patch creates a new file named string_sysfs.c

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 v2: restored sysfs_streq() which had been lost in the move.

 lib/Makefile       |  3 +-
 lib/string.c       | 79 ------------------------------------------------
 lib/string_sysfs.c | 88 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 90 insertions(+), 80 deletions(-)
 create mode 100644 lib/string_sysfs.c

diff --git a/lib/Makefile b/lib/Makefile
index 3b08673e8881..30b9b0bfbba9 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -12,12 +12,13 @@ endif
 # flaky coverage that is not a function of syscall inputs. For example,
 # rbtree can be global and individual rotations don't correlate with inputs.
 KCOV_INSTRUMENT_string.o := n
+KCOV_INSTRUMENT_string_sysfs.o := n
 KCOV_INSTRUMENT_rbtree.o := n
 KCOV_INSTRUMENT_list_debug.o := n
 KCOV_INSTRUMENT_debugobjects.o := n
 KCOV_INSTRUMENT_dynamic_debug.o := n
 
-lib-y := ctype.o string.o vsprintf.o cmdline.o \
+lib-y := ctype.o string.o string_sysfs.o vsprintf.o cmdline.o \
 	 rbtree.o radix-tree.o timerqueue.o xarray.o \
 	 idr.o int_sqrt.o extable.o \
 	 sha1.o chacha.o irq_regs.o argv_split.o \
diff --git a/lib/string.c b/lib/string.c
index 38e4ca08e757..f3886c5175ac 100644
--- a/lib/string.c
+++ b/lib/string.c
@@ -605,85 +605,6 @@ char *strsep(char **s, const char *ct)
 EXPORT_SYMBOL(strsep);
 #endif
 
-/**
- * sysfs_streq - return true if strings are equal, modulo trailing newline
- * @s1: one string
- * @s2: another string
- *
- * This routine returns true iff two strings are equal, treating both
- * NUL and newline-then-NUL as equivalent string terminations.  It's
- * geared for use with sysfs input strings, which generally terminate
- * with newlines but are compared against values without newlines.
- */
-bool sysfs_streq(const char *s1, const char *s2)
-{
-	while (*s1 && *s1 == *s2) {
-		s1++;
-		s2++;
-	}
-
-	if (*s1 == *s2)
-		return true;
-	if (!*s1 && *s2 == '\n' && !s2[1])
-		return true;
-	if (*s1 == '\n' && !s1[1] && !*s2)
-		return true;
-	return false;
-}
-EXPORT_SYMBOL(sysfs_streq);
-
-/**
- * match_string - matches given string in an array
- * @array:	array of strings
- * @n:		number of strings in the array or -1 for NULL terminated arrays
- * @string:	string to match with
- *
- * Return:
- * index of a @string in the @array if matches, or %-EINVAL otherwise.
- */
-int match_string(const char * const *array, size_t n, const char *string)
-{
-	int index;
-	const char *item;
-
-	for (index = 0; index < n; index++) {
-		item = array[index];
-		if (!item)
-			break;
-		if (!strcmp(item, string))
-			return index;
-	}
-
-	return -EINVAL;
-}
-EXPORT_SYMBOL(match_string);
-
-/**
- * __sysfs_match_string - matches given string in an array
- * @array: array of strings
- * @n: number of strings in the array or -1 for NULL terminated arrays
- * @str: string to match with
- *
- * Returns index of @str in the @array or -EINVAL, just like match_string().
- * Uses sysfs_streq instead of strcmp for matching.
- */
-int __sysfs_match_string(const char * const *array, size_t n, const char *str)
-{
-	const char *item;
-	int index;
-
-	for (index = 0; index < n; index++) {
-		item = array[index];
-		if (!item)
-			break;
-		if (sysfs_streq(item, str))
-			return index;
-	}
-
-	return -EINVAL;
-}
-EXPORT_SYMBOL(__sysfs_match_string);
-
 #ifndef __HAVE_ARCH_MEMSET
 /**
  * memset - Fill a region of memory with the given value
diff --git a/lib/string_sysfs.c b/lib/string_sysfs.c
new file mode 100644
index 000000000000..6c6bae70e6f7
--- /dev/null
+++ b/lib/string_sysfs.c
@@ -0,0 +1,88 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * stupid library routines for sysfs
+ *
+ */
+
+#include <linux/errno.h>
+#include <linux/export.h>
+#include <linux/string.h>
+
+/**
+ * sysfs_streq - return true if strings are equal, modulo trailing newline
+ * @s1: one string
+ * @s2: another string
+ *
+ * This routine returns true iff two strings are equal, treating both
+ * NUL and newline-then-NUL as equivalent string terminations.  It's
+ * geared for use with sysfs input strings, which generally terminate
+ * with newlines but are compared against values without newlines.
+ */
+bool sysfs_streq(const char *s1, const char *s2)
+{
+	while (*s1 && *s1 == *s2) {
+		s1++;
+		s2++;
+	}
+
+	if (*s1 == *s2)
+		return true;
+	if (!*s1 && *s2 == '\n' && !s2[1])
+		return true;
+	if (*s1 == '\n' && !s1[1] && !*s2)
+		return true;
+	return false;
+}
+EXPORT_SYMBOL(sysfs_streq);
+
+/**
+ * match_string - matches given string in an array
+ * @array:	array of strings
+ * @n:		number of strings in the array or -1 for NULL terminated arrays
+ * @string:	string to match with
+ *
+ * Return:
+ * index of a @string in the @array if matches, or %-EINVAL otherwise.
+ */
+int match_string(const char * const *array, size_t n, const char *string)
+{
+	int index;
+	const char *item;
+
+	for (index = 0; index < n; index++) {
+		item = array[index];
+		if (!item)
+			break;
+		if (!strcmp(item, string))
+			return index;
+	}
+
+	return -EINVAL;
+}
+EXPORT_SYMBOL(match_string);
+
+/**
+ * __sysfs_match_string - matches given string in an array
+ * @array: array of strings
+ * @n: number of strings in the array or -1 for NULL terminated arrays
+ * @str: string to match with
+ *
+ * Returns index of @str in the @array or -EINVAL, just like match_string().
+ * Uses sysfs_streq instead of strcmp for matching.
+ */
+int __sysfs_match_string(const char * const *array, size_t n, const char *str)
+{
+	const char *item;
+	int index;
+
+	for (index = 0; index < n; index++) {
+		item = array[index];
+		if (!item)
+			break;
+		if (sysfs_streq(item, str))
+			return index;
+	}
+
+	return -EINVAL;
+}
+EXPORT_SYMBOL(__sysfs_match_string);
-- 
2.13.3