1 /* Shell command argument quoting.
2 Copyright (C) 1994, 1995, 1997 Free Software Foundation, Inc.
3
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2, or (at your option)
7 any later version.
8
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
13
14 You should have received a copy of the GNU General Public License
15 along with this program; see the file COPYING.
16 If not, write to the Free Software Foundation,
17 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
18
19 /* Written by Paul Eggert <eggert@twinsun.com> */
20
21 #if HAVE_CONFIG_H
22 # include <config.h>
23 #endif
24
25 #include <sys/types.h>
26 #include <quotesys.h>
27
28 /* Place into QUOTED a quoted version of ARG suitable for `system'.
29 Return the length of the resulting string (which is not null-terminated).
30 If QUOTED is null, return the length without any side effects. */
31
32 size_t
quote_system_arg(quoted,arg)33 quote_system_arg (quoted, arg)
34 char *quoted;
35 char const *arg;
36 {
37 char const *a;
38 size_t len = 0;
39
40 /* Scan ARG, copying it to QUOTED if QUOTED is not null,
41 looking for shell metacharacters. */
42
43 for (a = arg; ; a++)
44 {
45 char c = *a;
46 switch (c)
47 {
48 case 0:
49 /* ARG has no shell metacharacters. */
50 return len;
51
52 case '=':
53 if (*arg == '-')
54 break;
55 /* Fall through. */
56 case '\t': case '\n': case ' ':
57 case '!': case '"': case '#': case '$': case '%': case '&': case '\'':
58 case '(': case ')': case '*': case ';':
59 case '<': case '>': case '?': case '[': case '\\':
60 case '^': case '`': case '|': case '~':
61 {
62 /* ARG has a shell metacharacter.
63 Start over, quoting it this time. */
64
65 len = 0;
66 c = *arg++;
67
68 /* If ARG is an option, quote just its argument.
69 This is not necessary, but it looks nicer. */
70 if (c == '-' && arg < a)
71 {
72 c = *arg++;
73
74 if (quoted)
75 {
76 quoted[len] = '-';
77 quoted[len + 1] = c;
78 }
79 len += 2;
80
81 if (c == '-')
82 while (arg < a)
83 {
84 c = *arg++;
85 if (quoted)
86 quoted[len] = c;
87 len++;
88 if (c == '=')
89 break;
90 }
91 c = *arg++;
92 }
93
94 if (quoted)
95 quoted[len] = '\'';
96 len++;
97
98 for (; c; c = *arg++)
99 {
100 if (c == '\'')
101 {
102 if (quoted)
103 {
104 quoted[len] = '\'';
105 quoted[len + 1] = '\\';
106 quoted[len + 2] = '\'';
107 }
108 len += 3;
109 }
110 if (quoted)
111 quoted[len] = c;
112 len++;
113 }
114
115 if (quoted)
116 quoted[len] = '\'';
117 return len + 1;
118 }
119 }
120
121 if (quoted)
122 quoted[len] = c;
123 len++;
124 }
125 }
126