make 'git describe --all --contains' work
[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 && (!arg || *arg == '-')) {
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 && (!arg || *arg == '-'))
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 && (!arg || !isdigit(*arg))) {
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 static NORETURN void usage_with_options_internal(const char * const *,
220                                                  const struct option *, int);
221
222 int parse_options(int argc, const char **argv, const struct option *options,
223                   const char * const usagestr[], int flags)
224 {
225         struct optparse_t args = { argv + 1, argc - 1, NULL };
226         int j = 0;
227
228         for (; args.argc; args.argc--, args.argv++) {
229                 const char *arg = args.argv[0];
230
231                 if (*arg != '-' || !arg[1]) {
232                         argv[j++] = args.argv[0];
233                         continue;
234                 }
235
236                 if (arg[1] != '-') {
237                         args.opt = arg + 1;
238                         do {
239                                 if (*args.opt == 'h')
240                                         usage_with_options(usagestr, options);
241                                 if (parse_short_opt(&args, options) < 0)
242                                         usage_with_options(usagestr, options);
243                         } while (args.opt);
244                         continue;
245                 }
246
247                 if (!arg[2]) { /* "--" */
248                         if (!(flags & PARSE_OPT_KEEP_DASHDASH)) {
249                                 args.argc--;
250                                 args.argv++;
251                         }
252                         break;
253                 }
254
255                 if (!strcmp(arg + 2, "help-all"))
256                         usage_with_options_internal(usagestr, options, 1);
257                 if (!strcmp(arg + 2, "help"))
258                         usage_with_options(usagestr, options);
259                 if (parse_long_opt(&args, arg + 2, options))
260                         usage_with_options(usagestr, options);
261         }
262
263         memmove(argv + j, args.argv, args.argc * sizeof(*argv));
264         argv[j + args.argc] = NULL;
265         return j + args.argc;
266 }
267
268 #define USAGE_OPTS_WIDTH 24
269 #define USAGE_GAP         2
270
271 void usage_with_options_internal(const char * const *usagestr,
272                                  const struct option *opts, int full)
273 {
274         fprintf(stderr, "usage: %s\n", *usagestr++);
275         while (*usagestr && **usagestr)
276                 fprintf(stderr, "   or: %s\n", *usagestr++);
277         while (*usagestr)
278                 fprintf(stderr, "    %s\n", *usagestr++);
279
280         if (opts->type != OPTION_GROUP)
281                 fputc('\n', stderr);
282
283         for (; opts->type != OPTION_END; opts++) {
284                 size_t pos;
285                 int pad;
286
287                 if (opts->type == OPTION_GROUP) {
288                         fputc('\n', stderr);
289                         if (*opts->help)
290                                 fprintf(stderr, "%s\n", opts->help);
291                         continue;
292                 }
293                 if (!full && (opts->flags & PARSE_OPT_HIDDEN))
294                         continue;
295
296                 pos = fprintf(stderr, "    ");
297                 if (opts->short_name)
298                         pos += fprintf(stderr, "-%c", opts->short_name);
299                 if (opts->long_name && opts->short_name)
300                         pos += fprintf(stderr, ", ");
301                 if (opts->long_name)
302                         pos += fprintf(stderr, "--%s", opts->long_name);
303
304                 switch (opts->type) {
305                 case OPTION_INTEGER:
306                         if (opts->flags & PARSE_OPT_OPTARG)
307                                 pos += fprintf(stderr, " [<n>]");
308                         else
309                                 pos += fprintf(stderr, " <n>");
310                         break;
311                 case OPTION_CALLBACK:
312                         if (opts->flags & PARSE_OPT_NOARG)
313                                 break;
314                         /* FALLTHROUGH */
315                 case OPTION_STRING:
316                         if (opts->argh) {
317                                 if (opts->flags & PARSE_OPT_OPTARG)
318                                         pos += fprintf(stderr, " [<%s>]", opts->argh);
319                                 else
320                                         pos += fprintf(stderr, " <%s>", opts->argh);
321                         } else {
322                                 if (opts->flags & PARSE_OPT_OPTARG)
323                                         pos += fprintf(stderr, " [...]");
324                                 else
325                                         pos += fprintf(stderr, " ...");
326                         }
327                         break;
328                 default: /* OPTION_{BIT,BOOLEAN,SET_INT,SET_PTR} */
329                         break;
330                 }
331
332                 if (pos <= USAGE_OPTS_WIDTH)
333                         pad = USAGE_OPTS_WIDTH - pos;
334                 else {
335                         fputc('\n', stderr);
336                         pad = USAGE_OPTS_WIDTH;
337                 }
338                 fprintf(stderr, "%*s%s\n", pad + USAGE_GAP, "", opts->help);
339         }
340         fputc('\n', stderr);
341
342         exit(129);
343 }
344
345 void usage_with_options(const char * const *usagestr,
346                         const struct option *opts)
347 {
348         usage_with_options_internal(usagestr, opts, 0);
349 }
350
351 /*----- some often used options -----*/
352 #include "cache.h"
353
354 int parse_opt_abbrev_cb(const struct option *opt, const char *arg, int unset)
355 {
356         int v;
357
358         if (!arg) {
359                 v = unset ? 0 : DEFAULT_ABBREV;
360         } else {
361                 v = strtol(arg, (char **)&arg, 10);
362                 if (*arg)
363                         return opterror(opt, "expects a numerical value", 0);
364                 if (v && v < MINIMUM_ABBREV)
365                         v = MINIMUM_ABBREV;
366                 else if (v > 40)
367                         v = 40;
368         }
369         *(int *)(opt->value) = v;
370         return 0;
371 }