1 /*++
2 /* NAME
3 /* mbox_conf 3
4 /* SUMMARY
5 /* mailbox lock configuration
6 /* SYNOPSIS
7 /* #include <mbox_conf.h>
8 /*
9 /* int mbox_lock_mask(string)
10 /* const char *string;
11 /*
12 /* ARGV *mbox_lock_names()
13 /* DESCRIPTION
14 /* The functions in this module translate between external
15 /* mailbox locking method names and internal representations.
16 /*
17 /* mbox_lock_mask() translates a string with locking method names
18 /* into a bit mask. Names are separated by comma or whitespace.
19 /* The following gives the method names and corresponding bit
20 /* mask value:
21 /* .IP "flock (MBOX_FLOCK_LOCK)"
22 /* Use flock() style lock after opening the file. This is the mailbox
23 /* locking method traditionally used on BSD-ish systems (including
24 /* Ultrix and SunOS). It is not suitable for remote file systems.
25 /* .IP "fcntl (MBOX_FCNTL_LOCK)"
26 /* Use fcntl() style lock after opening the file. This is the mailbox
27 /* locking method on System-V-ish systems (Solaris, AIX, IRIX, HP-UX).
28 /* This method is supposed to work for remote systems, but often
29 /* has problems.
30 /* .IP "dotlock (MBOX_DOT_LOCK)"
31 /* Create a lock file with the name \fIfilename\fB.lock\fR. This
32 /* method pre-dates kernel locks. This works with remote file systems,
33 /* modulo cache coherency problems.
34 /* .PP
35 /* mbox_lock_names() returns an array with the names of available
36 /* mailbox locking methods. The result should be given to argv_free().
37 /* DIAGNOSTICS
38 /* Fatal errors: undefined locking method name.
39 /* LICENSE
40 /* .ad
41 /* .fi
42 /* The Secure Mailer license must be distributed with this software.
43 /* AUTHOR(S)
44 /* Wietse Venema
45 /* IBM T.J. Watson Research
46 /* P.O. Box 704
47 /* Yorktown Heights, NY 10598, USA
48 /*--*/
49
50 /* System library. */
51
52 #include <sys_defs.h>
53
54 /* Utility library. */
55
56 #include <name_mask.h>
57 #include <argv.h>
58
59 /* Global library. */
60
61 #include <mail_params.h>
62 #include <mbox_conf.h>
63
64 /*
65 * The table with available mailbox locking methods. Some systems have
66 * flock() locks; all POSIX-compatible systems have fcntl() locks. Even
67 * though some systems do not use dotlock files by default (4.4BSD), such
68 * locks can be necessary when accessing mailbox files over NFS.
69 */
70 static const NAME_MASK mbox_mask[] = {
71 #ifdef HAS_FLOCK_LOCK
72 "flock", MBOX_FLOCK_LOCK,
73 #endif
74 #ifdef HAS_FCNTL_LOCK
75 "fcntl", MBOX_FCNTL_LOCK,
76 #endif
77 "dotlock", MBOX_DOT_LOCK,
78 0,
79 };
80
81 /* mbox_lock_mask - translate mailbox lock names to bit mask */
82
mbox_lock_mask(const char * string)83 int mbox_lock_mask(const char *string)
84 {
85 return (name_mask(VAR_MAILBOX_LOCK, mbox_mask, string));
86 }
87
88 /* mbox_lock_names - return available mailbox lock method names */
89
mbox_lock_names(void)90 ARGV *mbox_lock_names(void)
91 {
92 const NAME_MASK *np;
93 ARGV *argv;
94
95 argv = argv_alloc(2);
96 for (np = mbox_mask; np->name != 0; np++)
97 argv_add(argv, np->name, ARGV_END);
98 argv_terminate(argv);
99 return (argv);
100 }
101