string: fix type use in strstr()

Using plain int for string lengths, while okay for all practical
purposes, is undesirable in a generic library function.

Take the opportunity and also move the function from being in the middle
of mem*() ones to the set of str*() ones, convert its loop from while()
to for(), and correct style.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>

diff --git a/xen/common/string.c b/xen/common/string.c
index dafeaa827d3fbb5136f194ac7e7c27493652487e..a2bbe7dc97beba001ae701c1078c51d7f9fed15e 100644 (file)
--- a/xen/common/string.c
+++ b/xen/common/string.c
@@ -290,6 +290,27 @@ char * strsep(char **s, const char *ct)
 }
 #endif
 
+#ifndef __HAVE_ARCH_STRSTR
+/**
+ * strstr - Find the first substring in a %NUL terminated string
+ * @s1: The string to be searched
+ * @s2: The string to search for
+ */
+char *(strstr)(const char *s1, const char *s2)
+{
+       size_t l1, l2 = strlen(s2);
+
+       if (!l2)
+               return (char *)s1;
+
+       for (l1 = strlen(s1); l1 >= l2; --l1, ++s1)
+               if (!memcmp(s1, s2, l2))
+                       return (char *)s1;
+
+       return NULL;
+}
+#endif
+
 #ifndef __HAVE_ARCH_MEMSET
 /**
  * memset - Fill a region of memory with the given value
@@ -380,30 +401,6 @@ int (memcmp)(const void *cs, const void *ct, size_t count)
 }
 #endif
 
-#ifndef __HAVE_ARCH_STRSTR
-/**
- * strstr - Find the first substring in a %NUL terminated string
- * @s1: The string to be searched
- * @s2: The string to search for
- */
-char *(strstr)(const char *s1, const char *s2)
-{
-       int l1, l2;
-
-       l2 = strlen(s2);
-       if (!l2)
-               return (char *) s1;
-       l1 = strlen(s1);
-       while (l1 >= l2) {
-               l1--;
-               if (!memcmp(s1,s2,l2))
-                       return (char *) s1;
-               s1++;
-       }
-       return NULL;
-}
-#endif
-
 #ifndef __HAVE_ARCH_MEMCHR
 /**
  * memchr - Find a character in an area of memory.