From d2bb681f96fb327b4c4d5b2b113692ca22fdffbf Mon Sep 17 00:00:00 2001
From: Vasil Dimov <vd@FreeBSD.org>
Date: Mon, 31 Aug 2020 10:39:00 +0200
Subject: util: move HasPrefix() so it can be reused

Move the function `HasPrefix()` from `netaddress.cpp` to `util/string.h`
so it can be reused by `CNetAddr` methods (and possibly others).
---
 src/util/string.h | 13 +++++++++++++
 1 file changed, 13 insertions(+)

(limited to 'src/util')

diff --git a/src/util/string.h b/src/util/string.h
index cdb41630c6..a0c87bd00c 100644
--- a/src/util/string.h
+++ b/src/util/string.h
@@ -7,6 +7,8 @@
 
 #include <attributes.h>
 
+#include <algorithm>
+#include <array>
 #include <cstring>
 #include <locale>
 #include <sstream>
@@ -74,4 +76,15 @@ std::string ToString(const T& t)
     return oss.str();
 }
 
+/**
+ * Check whether a container begins with the given prefix.
+ */
+template <typename T1, size_t PREFIX_LEN>
+NODISCARD inline bool HasPrefix(const T1& obj,
+                                const std::array<uint8_t, PREFIX_LEN>& prefix)
+{
+    return obj.size() >= PREFIX_LEN &&
+           std::equal(std::begin(prefix), std::end(prefix), std::begin(obj));
+}
+
 #endif // BITCOIN_UTIL_STRENCODINGS_H
-- 
cgit v1.2.3