Prepare wpiutil for merge into allwpilib.

wpiutil/src/main/native/include/support/sha1.h

@@ -0,0 +1,56 @@
+/*
+    sha1.hpp - header of
+
+    ============
+    SHA-1 in C++
+    ============
+
+    100% Public Domain.
+
+    Original C Code
+        -- Steve Reid <steve@edmweb.com>
+    Small changes to fit into bglibs
+        -- Bruce Guenter <bruce@untroubled.org>
+    Translation to simpler C++ Code
+        -- Volker Grabsch <vog@notjusthosting.com>
+    Safety fixes
+        -- Eugene Hopkinson <slowriot at voxelstorm dot com>
+*/
+
+#ifndef WPIUTIL_SUPPORT_SHA1_H_
+#define WPIUTIL_SUPPORT_SHA1_H_
+
+#include <stdint.h>
+
+#include <string>
+
+#include "llvm/StringRef.h"
+
+namespace llvm {
+template <typename T>
+class SmallVectorImpl;
+}  // namespace llvm
+
+namespace wpi {
+
+class raw_istream;
+
+class SHA1 {
+ public:
+  SHA1();
+  void Update(llvm::StringRef s);
+  void Update(raw_istream& is);
+  std::string Final();
+  llvm::StringRef Final(llvm::SmallVectorImpl<char>& buf);
+  static std::string FromFile(llvm::StringRef filename);
+
+ private:
+  uint32_t digest[5];
+  unsigned char buffer[64];
+  size_t buf_size;
+  uint64_t transforms;
+};
+
+}  // namespace wpi
+
+#endif  // WPIUTIL_SUPPORT_SHA1_H_