1 /* argmatch.c -- find a match for a string in an array
2
3 Copyright (C) 1990, 1998, 1999, 2001, 2002, 2003, 2004, 2005 Free
4 Software Foundation, Inc.
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
17 along with this program; if not, write to the Free Software Foundation,
18 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
19
20 /* Written by David MacKenzie <djm@ai.mit.edu>
21 Modified by Akim Demaille <demaille@inf.enst.fr> */
22
23 #ifdef HAVE_CONFIG_H
24 # include <config.h>
25 #endif
26
27 /* Specification. */
28 #include "argmatch.h"
29
30 #include <stdbool.h>
31 #include <stdio.h>
32 #include <stdlib.h>
33 #include <string.h>
34
35 #include "gettext.h"
36 #define _(msgid) gettext (msgid)
37
38 #include "error.h"
39 #include "exit.h"
40 #include "quotearg.h"
41 #include "quote.h"
42
43 #if USE_UNLOCKED_IO
44 # include "unlocked-io.h"
45 #endif
46
47 /* When reporting an invalid argument, show nonprinting characters
48 by using the quoting style ARGMATCH_QUOTING_STYLE. Do not use
49 literal_quoting_style. */
50 #ifndef ARGMATCH_QUOTING_STYLE
51 # define ARGMATCH_QUOTING_STYLE locale_quoting_style
52 #endif
53
54 /* Non failing version of argmatch call this function after failing. */
55 #ifndef ARGMATCH_DIE
56 # include "exitfail.h"
57 # define ARGMATCH_DIE exit (exit_failure)
58 #endif
59
60 #ifdef ARGMATCH_DIE_DECL
61 ARGMATCH_DIE_DECL;
62 #endif
63
64 static void
__argmatch_die(void)65 __argmatch_die (void)
66 {
67 ARGMATCH_DIE;
68 }
69
70 /* Used by XARGMATCH and XARGCASEMATCH. See description in argmatch.h.
71 Default to __argmatch_die, but allow caller to change this at run-time. */
72 argmatch_exit_fn argmatch_die = __argmatch_die;
73
74
75 /* If ARG is an unambiguous match for an element of the
76 NULL-terminated array ARGLIST, return the index in ARGLIST
77 of the matched element, else -1 if it does not match any element
78 or -2 if it is ambiguous (is a prefix of more than one element).
79
80 If VALLIST is none null, use it to resolve ambiguities limited to
81 synonyms, i.e., for
82 "yes", "yop" -> 0
83 "no", "nope" -> 1
84 "y" is a valid argument, for `0', and "n" for `1'. */
85
86 ptrdiff_t
argmatch(const char * arg,const char * const * arglist,const char * vallist,size_t valsize)87 argmatch (const char *arg, const char *const *arglist,
88 const char *vallist, size_t valsize)
89 {
90 size_t i; /* Temporary index in ARGLIST. */
91 size_t arglen; /* Length of ARG. */
92 ptrdiff_t matchind = -1; /* Index of first nonexact match. */
93 bool ambiguous = false; /* If true, multiple nonexact match(es). */
94
95 arglen = strlen (arg);
96
97 /* Test all elements for either exact match or abbreviated matches. */
98 for (i = 0; arglist[i]; i++)
99 {
100 if (!strncmp (arglist[i], arg, arglen))
101 {
102 if (strlen (arglist[i]) == arglen)
103 /* Exact match found. */
104 return i;
105 else if (matchind == -1)
106 /* First nonexact match found. */
107 matchind = i;
108 else
109 {
110 /* Second nonexact match found. */
111 if (vallist == NULL
112 || memcmp (vallist + valsize * matchind,
113 vallist + valsize * i, valsize))
114 {
115 /* There is a real ambiguity, or we could not
116 disambiguate. */
117 ambiguous = true;
118 }
119 }
120 }
121 }
122 if (ambiguous)
123 return -2;
124 else
125 return matchind;
126 }
127
128 /* Error reporting for argmatch.
129 CONTEXT is a description of the type of entity that was being matched.
130 VALUE is the invalid value that was given.
131 PROBLEM is the return value from argmatch. */
132
133 void
argmatch_invalid(const char * context,const char * value,ptrdiff_t problem)134 argmatch_invalid (const char *context, const char *value, ptrdiff_t problem)
135 {
136 char const *format = (problem == -1
137 ? _("invalid argument %s for %s")
138 : _("ambiguous argument %s for %s"));
139
140 error (0, 0, format, quotearg_n_style (0, ARGMATCH_QUOTING_STYLE, value),
141 quote_n (1, context));
142 }
143
144 /* List the valid arguments for argmatch.
145 ARGLIST is the same as in argmatch.
146 VALLIST is a pointer to an array of values.
147 VALSIZE is the size of the elements of VALLIST */
148 void
argmatch_valid(const char * const * arglist,const char * vallist,size_t valsize)149 argmatch_valid (const char *const *arglist,
150 const char *vallist, size_t valsize)
151 {
152 size_t i;
153 const char *last_val = NULL;
154
155 /* We try to put synonyms on the same line. The assumption is that
156 synonyms follow each other */
157 fprintf (stderr, _("Valid arguments are:"));
158 for (i = 0; arglist[i]; i++)
159 if ((i == 0)
160 || memcmp (last_val, vallist + valsize * i, valsize))
161 {
162 fprintf (stderr, "\n - `%s'", arglist[i]);
163 last_val = vallist + valsize * i;
164 }
165 else
166 {
167 fprintf (stderr, ", `%s'", arglist[i]);
168 }
169 putc ('\n', stderr);
170 }
171
172 /* Never failing versions of the previous functions.
173
174 CONTEXT is the context for which argmatch is called (e.g.,
175 "--version-control", or "$VERSION_CONTROL" etc.). Upon failure,
176 calls the (supposed never to return) function EXIT_FN. */
177
178 ptrdiff_t
__xargmatch_internal(const char * context,const char * arg,const char * const * arglist,const char * vallist,size_t valsize,argmatch_exit_fn exit_fn)179 __xargmatch_internal (const char *context,
180 const char *arg, const char *const *arglist,
181 const char *vallist, size_t valsize,
182 argmatch_exit_fn exit_fn)
183 {
184 ptrdiff_t res = argmatch (arg, arglist, vallist, valsize);
185 if (res >= 0)
186 /* Success. */
187 return res;
188
189 /* We failed. Explain why. */
190 argmatch_invalid (context, arg, res);
191 argmatch_valid (arglist, vallist, valsize);
192 (*exit_fn) ();
193
194 return -1; /* To please the compilers. */
195 }
196
197 /* Look for VALUE in VALLIST, an array of objects of size VALSIZE and
198 return the first corresponding argument in ARGLIST */
199 const char *
argmatch_to_argument(const char * value,const char * const * arglist,const char * vallist,size_t valsize)200 argmatch_to_argument (const char *value,
201 const char *const *arglist,
202 const char *vallist, size_t valsize)
203 {
204 size_t i;
205
206 for (i = 0; arglist[i]; i++)
207 if (!memcmp (value, vallist + valsize * i, valsize))
208 return arglist[i];
209 return NULL;
210 }
211
212 #ifdef TEST
213 /*
214 * Based on "getversion.c" by David MacKenzie <djm@gnu.ai.mit.edu>
215 */
216 char *program_name;
217
218 /* When to make backup files. */
219 enum backup_type
220 {
221 /* Never make backups. */
222 no_backups,
223
224 /* Make simple backups of every file. */
225 simple_backups,
226
227 /* Make numbered backups of files that already have numbered backups,
228 and simple backups of the others. */
229 numbered_existing_backups,
230
231 /* Make numbered backups of every file. */
232 numbered_backups
233 };
234
235 /* Two tables describing arguments (keys) and their corresponding
236 values */
237 static const char *const backup_args[] =
238 {
239 "no", "none", "off",
240 "simple", "never",
241 "existing", "nil",
242 "numbered", "t",
243 0
244 };
245
246 static const enum backup_type backup_vals[] =
247 {
248 no_backups, no_backups, no_backups,
249 simple_backups, simple_backups,
250 numbered_existing_backups, numbered_existing_backups,
251 numbered_backups, numbered_backups
252 };
253
254 int
main(int argc,const char * const * argv)255 main (int argc, const char *const *argv)
256 {
257 const char *cp;
258 enum backup_type backup_type = no_backups;
259
260 program_name = (char *) argv[0];
261
262 if (argc > 2)
263 {
264 fprintf (stderr, "Usage: %s [VERSION_CONTROL]\n", program_name);
265 exit (1);
266 }
267
268 if ((cp = getenv ("VERSION_CONTROL")))
269 backup_type = XARGMATCH ("$VERSION_CONTROL", cp,
270 backup_args, backup_vals);
271
272 if (argc == 2)
273 backup_type = XARGMATCH (program_name, argv[1],
274 backup_args, backup_vals);
275
276 printf ("The version control is `%s'\n",
277 ARGMATCH_TO_ARGUMENT (backup_type, backup_args, backup_vals));
278
279 return 0;
280 }
281 #endif
282