[libc] Add strncasecmp()

Signed-off-by: Michael Brown <mcb30@ipxe.org>

1 files changed, 16 insertions, 1 deletions

diff --git a/src/core/string.c b/src/core/string.c
index 188fe0864..9a1b9b72a 100644
--- a/src/core/string.c
+++ b/src/core/string.c
@@ -27,6 +27,7 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 #include <stdint.h>
 #include <stdlib.h>
 #include <string.h>
+#include <strings.h>
 #include <ctype.h>
 
 /** @file
@@ -205,11 +206,24 @@ int strncmp ( const char *first, const char *second, size_t max ) {
  * @ret diff		Difference
  */
 int strcasecmp ( const char *first, const char *second ) {
+
+	return strncasecmp ( first, second, ~( ( size_t ) 0 ) );
+}
+
+/**
+ * Compare case-insensitive strings
+ *
+ * @v first		First string
+ * @v second		Second string
+ * @v max		Maximum length to compare
+ * @ret diff		Difference
+ */
+int strncasecmp ( const char *first, const char *second, size_t max ) {
 	const uint8_t *first_bytes = ( ( const uint8_t * ) first );
 	const uint8_t *second_bytes = ( ( const uint8_t * ) second );
 	int diff;
 
-	for ( ; ; first_bytes++, second_bytes++ ) {
+	for ( ; max-- ; first_bytes++, second_bytes++ ) {
 		diff = ( toupper ( *first_bytes ) -
 			 toupper ( *second_bytes ) );
 		if ( diff )
@@ -217,6 +231,7 @@ int strcasecmp ( const char *first, const char *second ) {
 		if ( ! *first_bytes )
 			return 0;
 	}
+	return 0;
 }
 
 /**