librsync: backport upstream fix

Closes Homebrew/homebrew#49770.

Formula/librsync.rb

@@ -1,8 +1,9 @@
 class Librsync < Formula
   desc "Library that implements the rsync remote-delta algorithm"
-  homepage "http://librsync.sourceforge.net/"
+  homepage "http://librsync.sourcefrog.net/"
   url "https://github.com/librsync/librsync/archive/v2.0.0.tar.gz"
   sha256 "b5c4dd114289832039397789e42d4ff0d1108ada89ce74f1999398593fae2169"
+  revision 1
 
   bottle do
     sha256 "7205930ff0e86bee031c515209bfb8ef9920274420eaa23701756ce4ae32fb15" => :el_capitan
@@ -18,7 +19,18 @@ class Librsync < Formula
   def install
     ENV.universal_binary if build.universal?
 
+    # https://github.com/librsync/librsync/commit/1765ad0d416
+    # https://github.com/librsync/librsync/issues/50
+    # Safe to remove when the next stable release is cut.
+    inreplace "src/search.c", "if (l == r) {", "if ((l == r) && (l <= bucket->r)) {"
+
     system "cmake", ".", *std_cmake_args
     system "make", "install"
+    man1.install "doc/rdiff.1"
+    man3.install "doc/librsync.3"
+  end
+
+  test do
+    assert_match version.to_s, shell_output("#{bin}/rdiff -V")
   end
 end