zipl/boot: add strlcpy implementation

add strlcpy from libutil to the zipl boot mini libc.

Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>

zipl/boot/libc.c

@@ -97,6 +97,33 @@ char *strcpy(char *dest, const char *src)
 	return dest;
 }
 
+/**
+ * Copy \a src to buffer \a dest of size \a size. At most size - 1
+ * chars will be copied. \a dest will always be NUL terminated.
+ *
+ * Note: If the return value is greater than or equal to size truncation
+ * occurred.
+ *
+ * @param[in] dest   Destination buffer
+ * @param[in] src    Source string
+ * @param[in] size   Size of destination buffer
+ *
+ * @returns   strlen Length of \a src string
+ */
+size_t strlcpy(char *dest, const char *src, size_t size)
+{
+	size_t str_len = strlen(src);
+	size_t len;
+
+	if (size) {
+		len = MIN(size - 1, str_len);
+		memcpy(dest, src, len);
+		dest[len] = '\0';
+	}
+
+	return str_len;
+}
+
 /*
  * Return string length
  */

zipl/boot/libc.h

@@ -54,6 +54,7 @@ char *strcat(char *, const char *);
 int strncmp(const char *, const char *, unsigned long);
 int strlen(const char *);
 char *strcpy(char *, const char *);
+size_t strlcpy(char *dest, const char *src, size_t size);
 char *strchr(const char *str, char c);
 unsigned int strhash(unsigned char *str, unsigned int hash_size);
 unsigned long get_zeroed_page(void);