You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: path.go
    path of file: ./repos/podman/vendor/github.com/gin-gonic/gin
    
    the code of the file until where you have to start completion: // 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
// at https://github.com/julienschmidt/httprouter/blob/master/LICENSE.

package gin

// cleanPath 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
    
func cleanPath(p string) string {
	const stackBufSize = 128
	// Turn empty string into "/"
	if p == "" {
		return "/"
	}

	// Reasonably sized buffer on stack to avoid allocations in the common case.
	// If a larger buffer is required, it gets allocated dynamically.
	buf := make([]byte, 0, stackBufSize)

	n := len(p)

	// 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

		if n+1 > stackBufSize {
			buf = make([]byte, n+1)
		} else {
			buf = buf[:n+1]
		}
		buf[0] = '/'
	}

	trailing := n > 1 && p[n-1] == '/'

	// A bit more clunky without a 'lazybuf' like the path package, but the loop
	// gets completely inlined (bufApp calls).
	// loop has no expensive function calls (except 1x make)		// So in contrast to the path package this loop has no expensive function
	// calls (except make, if needed).

	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 += 2

		case p[r] == '.' && p[r+1] == '.' && (r+2 == n || p[r+2] == '/'):
			// .. element: remove to last /
			r += 3

			if w > 1 {
				// can backtrack
				w--

				if len(buf) == 0 {
					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++
	}

	// If the original string was not modified (or only shortened at the end),
	// return the respective substring of the original string.
	// Otherwise return a new string from the buffer.
	if len(buf) == 0 {
		return p[:w]
	}
	return string(buf[:w])
}