xref: /freebsd/contrib/diff/lib/getopt.h (revision 38f0b757fd84d17d0fc24739a7cda160c4516d81)
1 /* Declarations for getopt.
2    Copyright (C) 1989-1994,1996-1999,2001,2003,2004
3    Free Software Foundation, Inc.
4    This file is part of the GNU C Library.
5 
6    This program is free software; you can redistribute it and/or modify
7    it under the terms of the GNU General Public License as published by
8    the Free Software Foundation; either version 2, or (at your option)
9    any later version.
10 
11    This program is distributed in the hope that it will be useful,
12    but WITHOUT ANY WARRANTY; without even the implied warranty of
13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14    GNU General Public License for more details.
15 
16    You should have received a copy of the GNU General Public License along
17    with this program; if not, write to the Free Software Foundation,
18    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
19 
20 #ifndef _GETOPT_H
21 
22 #ifndef __need_getopt
23 # define _GETOPT_H 1
24 #endif
25 
26 /* If __GNU_LIBRARY__ is not already defined, either we are being used
27    standalone, or this is the first header included in the source file.
28    If we are being used with glibc, we need to include <features.h>, but
29    that does not exist if we are standalone.  So: if __GNU_LIBRARY__ is
30    not defined, include <ctype.h>, which will pull in <features.h> for us
31    if it's from glibc.  (Why ctype.h?  It's guaranteed to exist and it
32    doesn't flood the namespace with stuff the way some other headers do.)  */
33 #if !defined __GNU_LIBRARY__
34 # include <ctype.h>
35 #endif
36 
37 #ifndef __THROW
38 # ifndef __GNUC_PREREQ
39 #  define __GNUC_PREREQ(maj, min) (0)
40 # endif
41 # if defined __cplusplus && __GNUC_PREREQ (2,8)
42 #  define __THROW	throw ()
43 # else
44 #  define __THROW
45 # endif
46 #endif
47 
48 #ifdef	__cplusplus
49 extern "C" {
50 #endif
51 
52 /* For communication from `getopt' to the caller.
53    When `getopt' finds an option that takes an argument,
54    the argument value is returned here.
55    Also, when `ordering' is RETURN_IN_ORDER,
56    each non-option ARGV-element is returned here.  */
57 
58 extern char *optarg;
59 
60 /* Index in ARGV of the next element to be scanned.
61    This is used for communication to and from the caller
62    and for communication between successive calls to `getopt'.
63 
64    On entry to `getopt', zero means this is the first call; initialize.
65 
66    When `getopt' returns -1, this is the index of the first of the
67    non-option elements that the caller should itself scan.
68 
69    Otherwise, `optind' communicates from one call to the next
70    how much of ARGV has been scanned so far.  */
71 
72 extern int optind;
73 
74 /* Callers store zero here to inhibit the error message `getopt' prints
75    for unrecognized options.  */
76 
77 extern int opterr;
78 
79 /* Set to an option character which was unrecognized.  */
80 
81 extern int optopt;
82 
83 #ifndef __need_getopt
84 /* Describe the long-named options requested by the application.
85    The LONG_OPTIONS argument to getopt_long or getopt_long_only is a vector
86    of `struct option' terminated by an element containing a name which is
87    zero.
88 
89    The field `has_arg' is:
90    no_argument		(or 0) if the option does not take an argument,
91    required_argument	(or 1) if the option requires an argument,
92    optional_argument 	(or 2) if the option takes an optional argument.
93 
94    If the field `flag' is not NULL, it points to a variable that is set
95    to the value given in the field `val' when the option is found, but
96    left unchanged if the option is not found.
97 
98    To have a long-named option do something other than set an `int' to
99    a compiled-in constant, such as set a value from `optarg', set the
100    option's `flag' field to zero and its `val' field to a nonzero
101    value (the equivalent single-letter option character, if there is
102    one).  For long options that have a zero `flag' field, `getopt'
103    returns the contents of the `val' field.  */
104 
105 struct option
106 {
107   const char *name;
108   /* has_arg can't be an enum because some compilers complain about
109      type mismatches in all the code that assumes it is an int.  */
110   int has_arg;
111   int *flag;
112   int val;
113 };
114 
115 /* Names for the values of the `has_arg' field of `struct option'.  */
116 
117 # define no_argument		0
118 # define required_argument	1
119 # define optional_argument	2
120 #endif	/* need getopt */
121 
122 
123 /* Get definitions and prototypes for functions to process the
124    arguments in ARGV (ARGC of them, minus the program name) for
125    options given in OPTS.
126 
127    Return the option character from OPTS just read.  Return -1 when
128    there are no more options.  For unrecognized options, or options
129    missing arguments, `optopt' is set to the option letter, and '?' is
130    returned.
131 
132    The OPTS string is a list of characters which are recognized option
133    letters, optionally followed by colons, specifying that that letter
134    takes an argument, to be placed in `optarg'.
135 
136    If a letter in OPTS is followed by two colons, its argument is
137    optional.  This behavior is specific to the GNU `getopt'.
138 
139    The argument `--' causes premature termination of argument
140    scanning, explicitly telling `getopt' that there are no more
141    options.
142 
143    If OPTS begins with `--', then non-option arguments are treated as
144    arguments to the option '\0'.  This behavior is specific to the GNU
145    `getopt'.  */
146 
147 #ifdef __GNU_LIBRARY__
148 /* Many other libraries have conflicting prototypes for getopt, with
149    differences in the consts, in stdlib.h.  To avoid compilation
150    errors, only prototype getopt for the GNU C library.  */
151 extern int getopt (int ___argc, char *const *___argv, const char *__shortopts)
152        __THROW;
153 #else /* not __GNU_LIBRARY__ */
154 extern int getopt ();
155 #endif /* __GNU_LIBRARY__ */
156 
157 #ifndef __need_getopt
158 extern int getopt_long (int ___argc, char *const *___argv,
159 			const char *__shortopts,
160 		        const struct option *__longopts, int *__longind)
161        __THROW;
162 extern int getopt_long_only (int ___argc, char *const *___argv,
163 			     const char *__shortopts,
164 		             const struct option *__longopts, int *__longind)
165        __THROW;
166 
167 #endif
168 
169 #ifdef	__cplusplus
170 }
171 #endif
172 
173 /* Make sure we later can get all the definitions and declarations.  */
174 #undef __need_getopt
175 
176 #endif /* getopt.h */
177