Merge branch 'jc/submittingpatches'
[git] / parse-options.c
1 #include "git-compat-util.h"
2 #include "parse-options.h"
3
4 #define OPT_SHORT 1
5 #define OPT_UNSET 2
6
7 struct optparse_t {
8         const char **argv;
9         int argc;
10         const char *opt;
11 };
12
13 static inline const char *get_arg(struct optparse_t *p)
14 {
15         if (p->opt) {
16                 const char *res = p->opt;
17                 p->opt = NULL;
18                 return res;
19         }
20         p->argc--;
21         return *++p->argv;
22 }
23
24 static inline const char *skip_prefix(const char *str, const char *prefix)
25 {
26         size_t len = strlen(prefix);
27         return strncmp(str, prefix, len) ? NULL : str + len;
28 }
29
30 static int opterror(const struct option *opt, const char *reason, int flags)
31 {
32         if (flags & OPT_SHORT)
33                 return error("switch `%c' %s", opt->short_name, reason);
34         if (flags & OPT_UNSET)
35                 return error("option `no-%s' %s", opt->long_name, reason);
36         return error("option `%s' %s", opt->long_name, reason);
37 }
38
39 static int get_value(struct optparse_t *p,
40                      const struct option *opt, int flags)
41 {
42         const char *s, *arg;
43         const int unset = flags & OPT_UNSET;
44
45         if (unset && p->opt)
46                 return opterror(opt, "takes no value", flags);
47         if (unset && (opt->flags & PARSE_OPT_NONEG))
48                 return opterror(opt, "isn't available", flags);
49
50         if (!(flags & OPT_SHORT) && p->opt) {
51                 switch (opt->type) {
52                 case OPTION_CALLBACK:
53                         if (!(opt->flags & PARSE_OPT_NOARG))
54                                 break;
55                         /* FALLTHROUGH */
56                 case OPTION_BOOLEAN:
57                 case OPTION_BIT:
58                 case OPTION_SET_INT:
59                 case OPTION_SET_PTR:
60                         return opterror(opt, "takes no value", flags);
61                 default:
62                         break;
63                 }
64         }
65
66         arg = p->opt ? p->opt : (p->argc > 1 ? p->argv[1] : NULL);
67         switch (opt->type) {
68         case OPTION_BIT:
69                 if (unset)
70                         *(int *)opt->value &= ~opt->defval;
71                 else
72                         *(int *)opt->value |= opt->defval;
73                 return 0;
74
75         case OPTION_BOOLEAN:
76                 *(int *)opt->value = unset ? 0 : *(int *)opt->value + 1;
77                 return 0;
78
79         case OPTION_SET_INT:
80                 *(int *)opt->value = unset ? 0 : opt->defval;
81                 return 0;
82
83         case OPTION_SET_PTR:
84                 *(void **)opt->value = unset ? NULL : (void *)opt->defval;
85                 return 0;
86
87         case OPTION_STRING:
88                 if (unset) {
89                         *(const char **)opt->value = NULL;
90                         return 0;
91                 }
92                 if (opt->flags & PARSE_OPT_OPTARG && !p->opt) {
93                         *(const char **)opt->value = (const char *)opt->defval;
94                         return 0;
95                 }
96                 if (!arg)
97                         return opterror(opt, "requires a value", flags);
98                 *(const char **)opt->value = get_arg(p);
99                 return 0;
100
101         case OPTION_CALLBACK:
102                 if (unset)
103                         return (*opt->callback)(opt, NULL, 1);
104                 if (opt->flags & PARSE_OPT_NOARG)
105                         return (*opt->callback)(opt, NULL, 0);
106                 if (opt->flags & PARSE_OPT_OPTARG && !p->opt)
107                         return (*opt->callback)(opt, NULL, 0);
108                 if (!arg)
109                         return opterror(opt, "requires a value", flags);
110                 return (*opt->callback)(opt, get_arg(p), 0);
111
112         case OPTION_INTEGER:
113                 if (unset) {
114                         *(int *)opt->value = 0;
115                         return 0;
116                 }
117                 if (opt->flags & PARSE_OPT_OPTARG && !p->opt) {
118                         *(int *)opt->value = opt->defval;
119                         return 0;
120                 }
121                 if (!arg)
122                         return opterror(opt, "requires a value", flags);
123                 *(int *)opt->value = strtol(get_arg(p), (char **)&s, 10);
124                 if (*s)
125                         return opterror(opt, "expects a numerical value", flags);
126                 return 0;
127
128         default:
129                 die("should not happen, someone must be hit on the forehead");
130         }
131 }
132
133 static int parse_short_opt(struct optparse_t *p, const struct option *options)
134 {
135         for (; options->type != OPTION_END; options++) {
136                 if (options->short_name == *p->opt) {
137                         p->opt = p->opt[1] ? p->opt + 1 : NULL;
138                         return get_value(p, options, OPT_SHORT);
139                 }
140         }
141         return error("unknown switch `%c'", *p->opt);
142 }
143
144 static int parse_long_opt(struct optparse_t *p, const char *arg,
145                           const struct option *options)
146 {
147         const char *arg_end = strchr(arg, '=');
148         const struct option *abbrev_option = NULL, *ambiguous_option = NULL;
149         int abbrev_flags = 0, ambiguous_flags = 0;
150
151         if (!arg_end)
152                 arg_end = arg + strlen(arg);
153
154         for (; options->type != OPTION_END; options++) {
155                 const char *rest;
156                 int flags = 0;
157
158                 if (!options->long_name)
159                         continue;
160
161                 rest = skip_prefix(arg, options->long_name);
162                 if (!rest) {
163                         /* abbreviated? */
164                         if (!strncmp(options->long_name, arg, arg_end - arg)) {
165 is_abbreviated:
166                                 if (abbrev_option) {
167                                         /*
168                                          * If this is abbreviated, it is
169                                          * ambiguous. So when there is no
170                                          * exact match later, we need to
171                                          * error out.
172                                          */
173                                         ambiguous_option = abbrev_option;
174                                         ambiguous_flags = abbrev_flags;
175                                 }
176                                 if (!(flags & OPT_UNSET) && *arg_end)
177                                         p->opt = arg_end + 1;
178                                 abbrev_option = options;
179                                 abbrev_flags = flags;
180                                 continue;
181                         }
182                         /* negated and abbreviated very much? */
183                         if (!prefixcmp("no-", arg)) {
184                                 flags |= OPT_UNSET;
185                                 goto is_abbreviated;
186                         }
187                         /* negated? */
188                         if (strncmp(arg, "no-", 3))
189                                 continue;
190                         flags |= OPT_UNSET;
191                         rest = skip_prefix(arg + 3, options->long_name);
192                         /* abbreviated and negated? */
193                         if (!rest && !prefixcmp(options->long_name, arg + 3))
194                                 goto is_abbreviated;
195                         if (!rest)
196                                 continue;
197                 }
198                 if (*rest) {
199                         if (*rest != '=')
200                                 continue;
201                         p->opt = rest + 1;
202                 }
203                 return get_value(p, options, flags);
204         }
205
206         if (ambiguous_option)
207                 return error("Ambiguous option: %s "
208                         "(could be --%s%s or --%s%s)",
209                         arg,
210                         (ambiguous_flags & OPT_UNSET) ?  "no-" : "",
211                         ambiguous_option->long_name,
212                         (abbrev_flags & OPT_UNSET) ?  "no-" : "",
213                         abbrev_option->long_name);
214         if (abbrev_option)
215                 return get_value(p, abbrev_option, abbrev_flags);
216         return error("unknown option `%s'", arg);
217 }
218
219 void check_typos(const char *arg, const struct option *options)
220 {
221         if (strlen(arg) < 3)
222                 return;
223
224         if (!prefixcmp(arg, "no-")) {
225                 error ("did you mean `--%s` (with two dashes ?)", arg);
226                 exit(129);
227         }
228
229         for (; options->type != OPTION_END; options++) {
230                 if (!options->long_name)
231                         continue;
232                 if (!prefixcmp(options->long_name, arg)) {
233                         error ("did you mean `--%s` (with two dashes ?)", arg);
234                         exit(129);
235                 }
236         }
237 }
238
239 static NORETURN void usage_with_options_internal(const char * const *,
240                                                  const struct option *, int);
241
242 int parse_options(int argc, const char **argv, const struct option *options,
243                   const char * const usagestr[], int flags)
244 {
245         struct optparse_t args = { argv + 1, argc - 1, NULL };
246         int j = 0;
247
248         for (; args.argc; args.argc--, args.argv++) {
249                 const char *arg = args.argv[0];
250
251                 if (*arg != '-' || !arg[1]) {
252                         argv[j++] = args.argv[0];
253                         continue;
254                 }
255
256                 if (arg[1] != '-') {
257                         args.opt = arg + 1;
258                         if (*args.opt == 'h')
259                                 usage_with_options(usagestr, options);
260                         if (parse_short_opt(&args, options) < 0)
261                                 usage_with_options(usagestr, options);
262                         if (args.opt)
263                                 check_typos(arg + 1, options);
264                         while (args.opt) {
265                                 if (*args.opt == 'h')
266                                         usage_with_options(usagestr, options);
267                                 if (parse_short_opt(&args, options) < 0)
268                                         usage_with_options(usagestr, options);
269                         }
270                         continue;
271                 }
272
273                 if (!arg[2]) { /* "--" */
274                         if (!(flags & PARSE_OPT_KEEP_DASHDASH)) {
275                                 args.argc--;
276                                 args.argv++;
277                         }
278                         break;
279                 }
280
281                 if (!strcmp(arg + 2, "help-all"))
282                         usage_with_options_internal(usagestr, options, 1);
283                 if (!strcmp(arg + 2, "help"))
284                         usage_with_options(usagestr, options);
285                 if (parse_long_opt(&args, arg + 2, options))
286                         usage_with_options(usagestr, options);
287         }
288
289         memmove(argv + j, args.argv, args.argc * sizeof(*argv));
290         argv[j + args.argc] = NULL;
291         return j + args.argc;
292 }
293
294 #define USAGE_OPTS_WIDTH 24
295 #define USAGE_GAP         2
296
297 void usage_with_options_internal(const char * const *usagestr,
298                                  const struct option *opts, int full)
299 {
300         fprintf(stderr, "usage: %s\n", *usagestr++);
301         while (*usagestr && **usagestr)
302                 fprintf(stderr, "   or: %s\n", *usagestr++);
303         while (*usagestr)
304                 fprintf(stderr, "    %s\n", *usagestr++);
305
306         if (opts->type != OPTION_GROUP)
307                 fputc('\n', stderr);
308
309         for (; opts->type != OPTION_END; opts++) {
310                 size_t pos;
311                 int pad;
312
313                 if (opts->type == OPTION_GROUP) {
314                         fputc('\n', stderr);
315                         if (*opts->help)
316                                 fprintf(stderr, "%s\n", opts->help);
317                         continue;
318                 }
319                 if (!full && (opts->flags & PARSE_OPT_HIDDEN))
320                         continue;
321
322                 pos = fprintf(stderr, "    ");
323                 if (opts->short_name)
324                         pos += fprintf(stderr, "-%c", opts->short_name);
325                 if (opts->long_name && opts->short_name)
326                         pos += fprintf(stderr, ", ");
327                 if (opts->long_name)
328                         pos += fprintf(stderr, "--%s", opts->long_name);
329
330                 switch (opts->type) {
331                 case OPTION_INTEGER:
332                         if (opts->flags & PARSE_OPT_OPTARG)
333                                 pos += fprintf(stderr, " [<n>]");
334                         else
335                                 pos += fprintf(stderr, " <n>");
336                         break;
337                 case OPTION_CALLBACK:
338                         if (opts->flags & PARSE_OPT_NOARG)
339                                 break;
340                         /* FALLTHROUGH */
341                 case OPTION_STRING:
342                         if (opts->argh) {
343                                 if (opts->flags & PARSE_OPT_OPTARG)
344                                         pos += fprintf(stderr, " [<%s>]", opts->argh);
345                                 else
346                                         pos += fprintf(stderr, " <%s>", opts->argh);
347                         } else {
348                                 if (opts->flags & PARSE_OPT_OPTARG)
349                                         pos += fprintf(stderr, " [...]");
350                                 else
351                                         pos += fprintf(stderr, " ...");
352                         }
353                         break;
354                 default: /* OPTION_{BIT,BOOLEAN,SET_INT,SET_PTR} */
355                         break;
356                 }
357
358                 if (pos <= USAGE_OPTS_WIDTH)
359                         pad = USAGE_OPTS_WIDTH - pos;
360                 else {
361                         fputc('\n', stderr);
362                         pad = USAGE_OPTS_WIDTH;
363                 }
364                 fprintf(stderr, "%*s%s\n", pad + USAGE_GAP, "", opts->help);
365         }
366         fputc('\n', stderr);
367
368         exit(129);
369 }
370
371 void usage_with_options(const char * const *usagestr,
372                         const struct option *opts)
373 {
374         usage_with_options_internal(usagestr, opts, 0);
375 }
376
377 /*----- some often used options -----*/
378 #include "cache.h"
379
380 int parse_opt_abbrev_cb(const struct option *opt, const char *arg, int unset)
381 {
382         int v;
383
384         if (!arg) {
385                 v = unset ? 0 : DEFAULT_ABBREV;
386         } else {
387                 v = strtol(arg, (char **)&arg, 10);
388                 if (*arg)
389                         return opterror(opt, "expects a numerical value", 0);
390                 if (v && v < MINIMUM_ABBREV)
391                         v = MINIMUM_ABBREV;
392                 else if (v > 40)
393                         v = 40;
394         }
395         *(int *)(opt->value) = v;
396         return 0;
397 }