bytestring: bytestring_starts() and bytestring_ends() functions

[ccan] / ccan / bytestring / bytestring.h

diff --git a/ccan/bytestring/bytestring.h b/ccan/bytestring/bytestring.h
index abc7dd7bb0424bb684bdd5000006cfce97cc8578..54e9fa8735122a70f7d7b032b8c776ead3096297 100644 (file)
--- a/ccan/bytestring/bytestring.h
+++ b/ccan/bytestring/bytestring.h
@@ -122,4 +122,32 @@ static inline struct bytestring bytestring_slice(struct bytestring s,
        return bytestring(s.ptr + start, end - start);
 }
 
+/**
+ * bytestring_starts - test if the start of one bytestring matches another
+ * @s, @prefix: bytestrings
+ *
+ * Returns true if @prefix appears as a substring at the beginning of
+ * @s, false otherwise.
+ */
+static inline bool bytestring_starts(struct bytestring s,
+                                    struct bytestring prefix)
+{
+       return (s.len >= prefix.len) && (memcmp(s.ptr,
+                                               prefix.ptr, prefix.len) == 0);
+}
+
+/**
+ * bytestring_ends - test if the end of one bytestring matches another
+ * @s, @suffix: bytestrings
+ *
+ * Returns true if @suffix appears as a substring at the end of @s,
+ * false otherwise.
+ */
+static inline bool bytestring_ends(struct bytestring s,
+                                  struct bytestring suffix)
+{
+       return (s.len >= suffix.len) && (memcmp(s.ptr + s.len - suffix.len,
+                                               suffix.ptr, suffix.len) == 0);
+}
+
 #endif /* CCAN_BYTESTRING_H_ */