utils: Add memrchr(3) replacement for platforms that don't support it

For instance, on Mac OS X memrchr(3) is not provided by the C library.

1 files changed, 23 insertions, 1 deletions

diff --git a/src/libstrongswan/utils/utils.c b/src/libstrongswan/utils/utils.c
index 406c5c811..fe80edb82 100644
--- a/src/libstrongswan/utils/utils.c
+++ b/src/libstrongswan/utils/utils.c
@@ -103,7 +103,7 @@ void memwipe_noinline(void *ptr, size_t n)
  */
 void *memstr(const void *haystack, const char *needle, size_t n)
 {
-	unsigned const char *pos = haystack;
+	const u_char *pos = haystack;
 	size_t l;
 
 	if (!haystack || !needle || (l = strlen(needle)) == 0)
@@ -123,6 +123,28 @@ void *memstr(const void *haystack, const char *needle, size_t n)
 /**
  * Described in header.
  */
+void *utils_memrchr(const void *s, int c, size_t n)
+{
+	const u_char *pos;
+
+	if (!s || !n)
+	{
+		return NULL;
+	}
+
+	for (pos = s + n - 1; pos >= (u_char*)s; pos--)
+	{
+		if (*pos == (u_char)c)
+		{
+			return (void*)pos;
+		}
+	}
+	return NULL;
+}
+
+/**
+ * Described in header.
+ */
 char* translate(char *str, const char *from, const char *to)
 {
 	char *pos = str;