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authorLibravatar Tobi Smethurst <31960611+tsmethurst@users.noreply.github.com>2021-08-12 21:03:24 +0200
committerLibravatar GitHub <noreply@github.com>2021-08-12 21:03:24 +0200
commit98263a7de64269898a2f81207e38943b5c8e8653 (patch)
tree743c90f109a6c5d27832d1dcef2388d939f0f77a /vendor/github.com/gin-gonic/gin/path.go
parentText duplication fix (#137) (diff)
downloadgotosocial-98263a7de64269898a2f81207e38943b5c8e8653.tar.xz
Grand test fixup (#138)
* start fixing up tests * fix up tests + automate with drone * fiddle with linting * messing about with drone.yml * some more fiddling * hmmm * add cache * add vendor directory * verbose * ci updates * update some little things * update sig
Diffstat (limited to 'vendor/github.com/gin-gonic/gin/path.go')
-rw-r--r--vendor/github.com/gin-gonic/gin/path.go150
1 files changed, 150 insertions, 0 deletions
diff --git a/vendor/github.com/gin-gonic/gin/path.go b/vendor/github.com/gin-gonic/gin/path.go
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+++ b/vendor/github.com/gin-gonic/gin/path.go
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+// 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. 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 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])
+}
+
+// Internal helper to lazily create a buffer if necessary.
+// Calls to this function get inlined.
+func bufApp(buf *[]byte, s string, w int, c byte) {
+ b := *buf
+ if len(b) == 0 {
+ // No modification of the original string so far.
+ // If the next character is the same as in the original string, we do
+ // not yet have to allocate a buffer.
+ if s[w] == c {
+ return
+ }
+
+ // Otherwise use either the stack buffer, if it is large enough, or
+ // allocate a new buffer on the heap, and copy all previous characters.
+ length := len(s)
+ if length > cap(b) {
+ *buf = make([]byte, length)
+ } else {
+ *buf = (*buf)[:length]
+ }
+ b = *buf
+
+ copy(b, s[:w])
+ }
+ b[w] = c
+}