1// -build windows
2
3// Copyright 2015 go-swagger maintainers
4//
5// Licensed under the Apache License, Version 2.0 (the "License");
6// you may not use this file except in compliance with the License.
7// You may obtain a copy of the License at
8//
9//    http://www.apache.org/licenses/LICENSE-2.0
10//
11// Unless required by applicable law or agreed to in writing, software
12// distributed under the License is distributed on an "AS IS" BASIS,
13// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14// See the License for the specific language governing permissions and
15// limitations under the License.
16
17package spec
18
19import (
20	"net/url"
21	"os"
22	"path"
23	"path/filepath"
24	"strings"
25)
26
27// absPath makes a file path absolute and compatible with a URI path component
28//
29// The parameter must be a path, not an URI.
30func absPath(in string) string {
31	// NOTE(windows): filepath.Abs exhibits a special behavior on windows for empty paths.
32	// See https://github.com/golang/go/issues/24441
33	if in == "" {
34		in = "."
35	}
36
37	anchored, err := filepath.Abs(in)
38	if err != nil {
39		specLogger.Printf("warning: could not resolve current working directory: %v", err)
40		return in
41	}
42
43	pth := strings.ReplaceAll(strings.ToLower(anchored), `\`, `/`)
44	if !strings.HasPrefix(pth, "/") {
45		pth = "/" + pth
46	}
47
48	return path.Clean(pth)
49}
50
51// repairURI tolerates invalid file URIs with common typos
52// such as 'file://E:\folder\file', that break the regular URL parser.
53//
54// Adopting the same defaults as for unixes (e.g. return an empty path) would
55// result into a counter-intuitive result for that case (e.g. E:\folder\file is
56// eventually resolved as the current directory). The repair will detect the missing "/".
57//
58// Note that this only works for the file scheme.
59func repairURI(in string) (*url.URL, string) {
60	const prefix = fileScheme + "://"
61	if !strings.HasPrefix(in, prefix) {
62		// giving up: resolve to empty path
63		u, _ := url.Parse("")
64
65		return u, ""
66	}
67
68	// attempt the repair, stripping the scheme should be sufficient
69	u, _ := url.Parse(strings.TrimPrefix(in, prefix))
70	debugLog("repaired URI: original: %q, repaired: %q", in, u.String())
71
72	return u, u.String()
73}
74
75// fixWindowsURI tolerates an absolute file path on windows such as C:\Base\File.yaml or \\host\share\Base\File.yaml
76// and makes it a canonical URI: file:///c:/base/file.yaml
77//
78// Catch 22 notes for Windows:
79//
80// * There may be a drive letter on windows (it is lower-cased)
81// * There may be a share UNC, e.g. \\server\folder\data.xml
82// * Paths are case insensitive
83// * Paths may already contain slashes
84// * Paths must be slashed
85//
86// NOTE: there is no escaping. "/" may be valid separators just like "\".
87// We don't use ToSlash() (which escapes everything) because windows now also
88// tolerates the use of "/". Hence, both C:\File.yaml and C:/File.yaml will work.
89func fixWindowsURI(u *url.URL, in string) {
90	drive := filepath.VolumeName(in)
91
92	if len(drive) > 0 {
93		if len(u.Scheme) == 1 && strings.EqualFold(u.Scheme, drive[:1]) { // a path with a drive letter
94			u.Scheme = fileScheme
95			u.Host = ""
96			u.Path = strings.Join([]string{drive, u.Opaque, u.Path}, `/`) // reconstruct the full path component (no fragment, no query)
97		} else if u.Host == "" && strings.HasPrefix(u.Path, drive) { // a path with a \\host volume
98			// NOTE: the special host@port syntax for UNC is not supported (yet)
99			u.Scheme = fileScheme
100
101			// this is a modified version of filepath.Dir() to apply on the VolumeName itself
102			i := len(drive) - 1
103			for i >= 0 && !os.IsPathSeparator(drive[i]) {
104				i--
105			}
106			host := drive[:i] // \\host\share => host
107
108			u.Path = strings.TrimPrefix(u.Path, host)
109			u.Host = strings.TrimPrefix(host, `\\`)
110		}
111
112		u.Opaque = ""
113		u.Path = strings.ReplaceAll(strings.ToLower(u.Path), `\`, `/`)
114
115		// ensure we form an absolute path
116		if !strings.HasPrefix(u.Path, "/") {
117			u.Path = "/" + u.Path
118		}
119
120		u.Path = path.Clean(u.Path)
121
122		return
123	}
124
125	if u.Scheme == fileScheme {
126		// Handle dodgy cases for file://{...} URIs on windows.
127		// A canonical URI should always be followed by an absolute path.
128		//
129		// Examples:
130		//   * file:///folder/file => valid, unchanged
131		//   * file:///c:\folder\file => slashed
132		//   * file:///./folder/file => valid, cleaned to remove the dot
133		//   * file:///.\folder\file => remapped to cwd
134		//   * file:///. => dodgy, remapped to / (consistent with the behavior on unix)
135		//   * file:///.. => dodgy, remapped to / (consistent with the behavior on unix)
136		if (!path.IsAbs(u.Path) && !filepath.IsAbs(u.Path)) || (strings.HasPrefix(u.Path, `/.`) && strings.Contains(u.Path, `\`)) {
137			// ensure we form an absolute path
138			u.Path, _ = filepath.Abs(strings.TrimLeft(u.Path, `/`))
139			if !strings.HasPrefix(u.Path, "/") {
140				u.Path = "/" + u.Path
141			}
142		}
143		u.Path = strings.ToLower(u.Path)
144	}
145
146	// NOTE: lower case normalization does not propagate to inner resources,
147	// generated when rebasing: when joining a relative URI with a file to an absolute base,
148	// only the base is currently lower-cased.
149	//
150	// For now, we assume this is good enough for most use cases
151	// and try not to generate too many differences
152	// between the output produced on different platforms.
153	u.Path = path.Clean(strings.ReplaceAll(u.Path, `\`, `/`))
154}
155