1// Copyright 2016 Google Inc. All rights reserved.
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//     http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15package proptools
16
17import "strings"
18
19// NinjaEscapeList takes a slice of strings that may contain characters that are meaningful to ninja
20// ($), and escapes each string so they will be passed to bash.  It is not necessary on input,
21// output, or dependency names, those are handled by ModuleContext.Build.  It is generally required
22// on strings from properties in Blueprint files that are used as Args to ModuleContext.Build.  A
23// new slice containing the escaped strings is returned.
24func NinjaEscapeList(slice []string) []string {
25	slice = append([]string(nil), slice...)
26	for i, s := range slice {
27		slice[i] = NinjaEscape(s)
28	}
29	return slice
30}
31
32// NinjaEscapeList takes a string that may contain characters that are meaningful to ninja
33// ($), and escapes it so it will be passed to bash.  It is not necessary on input,
34// output, or dependency names, those are handled by ModuleContext.Build.  It is generally required
35// on strings from properties in Blueprint files that are used as Args to ModuleContext.Build.  A
36// new slice containing the escaped strings is returned.
37func NinjaEscape(s string) string {
38	return ninjaEscaper.Replace(s)
39}
40
41var ninjaEscaper = strings.NewReplacer(
42	"$", "$$")
43
44// ShellEscapeList takes a slice of strings that may contain characters that are meaningful to bash and
45// escapes them if necessary by wrapping them in single quotes, and replacing internal single quotes with
46// '\'' (one single quote to end the quoting, a shell-escaped single quote to insert a real single
47// quote, and then a single quote to restarting quoting.  A new slice containing the escaped strings
48// is returned.
49func ShellEscapeList(slice []string) []string {
50	slice = append([]string(nil), slice...)
51
52	for i, s := range slice {
53		slice[i] = ShellEscape(s)
54	}
55	return slice
56
57}
58
59// ShellEscapeList takes string that may contain characters that are meaningful to bash and
60// escapes it if necessary by wrapping it in single quotes, and replacing internal single quotes with
61// '\'' (one single quote to end the quoting, a shell-escaped single quote to insert a real single
62// quote, and then a single quote to restarting quoting.
63func ShellEscape(s string) string {
64	shellUnsafeChar := func(r rune) bool {
65		switch {
66		case 'A' <= r && r <= 'Z',
67			'a' <= r && r <= 'z',
68			'0' <= r && r <= '9',
69			r == '_',
70			r == '+',
71			r == '-',
72			r == '=',
73			r == '.',
74			r == ',',
75			r == '/',
76			r == ' ':
77			return false
78		default:
79			return true
80		}
81	}
82
83	if strings.IndexFunc(s, shellUnsafeChar) == -1 {
84		// No escaping necessary
85		return s
86	}
87
88	return `'` + singleQuoteReplacer.Replace(s) + `'`
89}
90
91func NinjaAndShellEscapeList(slice []string) []string {
92	return ShellEscapeList(NinjaEscapeList(slice))
93}
94
95func NinjaAndShellEscape(s string) string {
96	return ShellEscape(NinjaEscape(s))
97}
98
99var singleQuoteReplacer = strings.NewReplacer(`'`, `'\''`)
100