1 This file is umask.def, from which is created umask.c.
2 It implements the builtin "umask" in Bash.
4 Copyright (C) 1987, 1989, 1991 Free Software Foundation, Inc.
6 This file is part of GNU Bash, the Bourne Again SHell.
8 Bash is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 1, or (at your option) any later
13 Bash is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License along
19 with Bash; see the file COPYING. If not, write to the Free Software
20 Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
25 $FUNCTION umask_builtin
26 $SHORT_DOC umask [-S] [mode]
27 The user file-creation mask is set to MODE. If MODE is omitted, or if
28 `-S' is supplied, the current value of the mask is printed. The `-S'
29 option makes the output symbolic; otherwise an octal number is output.
30 If MODE begins with a digit, it is interpreted as an octal number,
31 otherwise it is a symbolic mode string like that accepted by chmod(1).
35 #include <sys/types.h>
38 #include "../posixstat.h"
41 /* **************************************************************** */
43 /* UMASK Builtin and Helpers */
45 /* **************************************************************** */
47 static void print_symbolic_umask ();
48 static int symbolic_umask ();
50 /* Set or display the mask used by the system when creating files. Flag
51 of -S means display the umask in a symbolic mode. */
55 int print_symbolically = 0;
59 if (ISOPTION (list->word->word, 'S'))
65 else if (ISOPTION (list->word->word, '-'))
70 else if (*(list->word->word) == '-')
72 bad_option (list->word->word);
73 builtin_error ("usage: umask [-S] [mode]");
84 if (digit (*list->word->word))
86 new_umask = read_octal (list->word->word);
88 /* Note that other shells just let you set the umask to zero
89 by specifying a number out of range. This is a problem
90 with those shells. We don't change the umask if the input
94 builtin_error ("`%s' is not an octal number from 000 to 777",
96 return (EXECUTION_FAILURE);
101 new_umask = symbolic_umask (list);
103 return (EXECUTION_FAILURE);
106 if (print_symbolically)
107 print_symbolic_umask (new_umask);
109 else /* Display the UMASK for this user. */
113 old_umask = umask (022);
116 if (print_symbolically)
117 print_symbolic_umask (old_umask);
119 printf ("%03o\n", old_umask);
122 return (EXECUTION_SUCCESS);
125 /* Print the umask in a symbolic form. In the output, a letter is
126 printed if the corresponding bit is clear in the umask. */
128 print_symbolic_umask (um)
131 char ubits[4], gbits[4], obits[4]; /* u=rwx,g=rwx,o=rwx */
135 if ((um & S_IRUSR) == 0)
137 if ((um & S_IWUSR) == 0)
139 if ((um & S_IXUSR) == 0)
144 if ((um & S_IRGRP) == 0)
146 if ((um & S_IWGRP) == 0)
148 if ((um & S_IXGRP) == 0)
153 if ((um & S_IROTH) == 0)
155 if ((um & S_IWOTH) == 0)
157 if ((um & S_IXOTH) == 0)
161 printf ("u=%s,g=%s,o=%s\n", ubits, gbits, obits);
164 /* Set the umask from a symbolic mode string similar to that accepted
165 by chmod. If the -S argument is given, then print the umask in a
168 symbolic_umask (list)
172 int who, op, perm, mask;
175 /* Get the initial umask. Don't change it yet. */
179 /* All work below is done with the complement of the umask -- its
180 more intuitive and easier to deal with. It is complemented
181 again before being returned. */
184 s = list->word->word;
188 who = op = perm = mask = 0;
190 /* Parse the `who' portion of the symbolic mode clause. */
191 while (member (*s, "agou"))
205 who |= S_IRWXU | S_IRWXG | S_IRWXO;
212 /* The operation is now sitting in *s. */
221 builtin_error ("bad symbolic mode operator: %c", op);
225 /* Parse out the `perm' section of the symbolic mode clause. */
226 while (member (*s, "rwx"))
246 /* Now perform the operation or return an error for a
247 bad permission string. */
248 if (!*s || *s == ',')
269 builtin_error ("bad operation character: %c", op);
279 s++; /* skip past ',' */
283 builtin_error ("bad character in symbolic mode: %c", *s);