Imported github.com/ardanlabs/service as base example project

example-project/vendor/github.com/dimfeld/httptreemux/path.go

@@ -0,0 +1,127 @@
+// Copyright 2013 Julien Schmidt. All rights reserved.
+// Based on the path package, Copyright 2009 The Go Authors.
+// Use of this source code is governed by a BSD-style license that can be found
+// in the LICENSE file.
+
+package httptreemux
+
+// Clean is the URL version of path.Clean, it returns a canonical URL path
+// for p, eliminating . and .. elements.
+//
+// The following rules are applied iteratively until no further processing can
+// be done:
+//	1. Replace multiple slashes with a single slash.
+//	2. Eliminate each . path name element (the current directory).
+//	3. Eliminate each inner .. path name element (the parent directory)
+//	   along with the non-.. element that precedes it.
+//	4. Eliminate .. elements that begin a rooted path:
+//	   that is, replace "/.." by "/" at the beginning of a path.
+//
+// If the result of this process is an empty string, "/" is returned
+func Clean(p string) string {
+	if p == "" {
+		return "/"
+	}
+
+	n := len(p)
+	var buf []byte
+
+	// Invariants:
+	//      reading from path; r is index of next byte to process.
+	//      writing to buf; w is index of next byte to write.
+
+	// path must start with '/'
+	r := 1
+	w := 1
+
+	if p[0] != '/' {
+		r = 0
+		buf = make([]byte, n+1)
+		buf[0] = '/'
+	}
+
+	trailing := n > 2 && p[n-1] == '/'
+
+	// A bit more clunky without a 'lazybuf' like the path package, but the loop
+	// gets completely inlined (bufApp). So in contrast to the path package this
+	// loop has no expensive function calls (except 1x make)
+
+	for r < n {
+		switch {
+		case p[r] == '/':
+			// empty path element, trailing slash is added after the end
+			r++
+
+		case p[r] == '.' && r+1 == n:
+			trailing = true
+			r++
+
+		case p[r] == '.' && p[r+1] == '/':
+			// . element
+			r++
+
+		case p[r] == '.' && p[r+1] == '.' && (r+2 == n || p[r+2] == '/'):
+			// .. element: remove to last /
+			r += 2
+
+			if w > 1 {
+				// can backtrack
+				w--
+
+				if buf == nil {
+					for w > 1 && p[w] != '/' {
+						w--
+					}
+				} else {
+					for w > 1 && buf[w] != '/' {
+						w--
+					}
+				}
+			}
+
+		default:
+			// real path element.
+			// add slash if needed
+			if w > 1 {
+				bufApp(&buf, p, w, '/')
+				w++
+			}
+
+			// copy element
+			for r < n && p[r] != '/' {
+				bufApp(&buf, p, w, p[r])
+				w++
+				r++
+			}
+		}
+	}
+
+	// re-append trailing slash
+	if trailing && w > 1 {
+		bufApp(&buf, p, w, '/')
+		w++
+	}
+
+	// Turn empty string into "/"
+	if w == 0 {
+		return "/"
+	}
+
+	if buf == nil {
+		return p[:w]
+	}
+	return string(buf[:w])
+}
+
+// internal helper to lazily create a buffer if necessary
+func bufApp(buf *[]byte, s string, w int, c byte) {
+	if *buf == nil {
+		if s[w] == c {
+			return
+		}
+
+		*buf = make([]byte, len(s))
+		copy(*buf, s[:w])
+	}
+	(*buf)[w] = c
+}