Move parse-options's skip_prefix() to git-compat-util.h
[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         const char **out;
10         int argc, cpidx;
11         const char *opt;
12 };
13
14 static inline const char *get_arg(struct optparse_t *p)
15 {
16         if (p->opt) {
17                 const char *res = p->opt;
18                 p->opt = NULL;
19                 return res;
20         }
21         p->argc--;
22         return *++p->argv;
23 }
24
25 static int opterror(const struct option *opt, const char *reason, int flags)
26 {
27         if (flags & OPT_SHORT)
28                 return error("switch `%c' %s", opt->short_name, reason);
29         if (flags & OPT_UNSET)
30                 return error("option `no-%s' %s", opt->long_name, reason);
31         return error("option `%s' %s", opt->long_name, reason);
32 }
33
34 static int get_value(struct optparse_t *p,
35                      const struct option *opt, int flags)
36 {
37         const char *s, *arg;
38         const int unset = flags & OPT_UNSET;
39
40         if (unset && p->opt)
41                 return opterror(opt, "takes no value", flags);
42         if (unset && (opt->flags & PARSE_OPT_NONEG))
43                 return opterror(opt, "isn't available", flags);
44
45         if (!(flags & OPT_SHORT) && p->opt) {
46                 switch (opt->type) {
47                 case OPTION_CALLBACK:
48                         if (!(opt->flags & PARSE_OPT_NOARG))
49                                 break;
50                         /* FALLTHROUGH */
51                 case OPTION_BOOLEAN:
52                 case OPTION_BIT:
53                 case OPTION_SET_INT:
54                 case OPTION_SET_PTR:
55                         return opterror(opt, "takes no value", flags);
56                 default:
57                         break;
58                 }
59         }
60
61         arg = p->opt ? p->opt : (p->argc > 1 ? p->argv[1] : NULL);
62         switch (opt->type) {
63         case OPTION_BIT:
64                 if (unset)
65                         *(int *)opt->value &= ~opt->defval;
66                 else
67                         *(int *)opt->value |= opt->defval;
68                 return 0;
69
70         case OPTION_BOOLEAN:
71                 *(int *)opt->value = unset ? 0 : *(int *)opt->value + 1;
72                 return 0;
73
74         case OPTION_SET_INT:
75                 *(int *)opt->value = unset ? 0 : opt->defval;
76                 return 0;
77
78         case OPTION_SET_PTR:
79                 *(void **)opt->value = unset ? NULL : (void *)opt->defval;
80                 return 0;
81
82         case OPTION_STRING:
83                 if (unset) {
84                         *(const char **)opt->value = NULL;
85                         return 0;
86                 }
87                 if (opt->flags & PARSE_OPT_OPTARG && !p->opt) {
88                         *(const char **)opt->value = (const char *)opt->defval;
89                         return 0;
90                 }
91                 if (!arg)
92                         return opterror(opt, "requires a value", flags);
93                 *(const char **)opt->value = get_arg(p);
94                 return 0;
95
96         case OPTION_CALLBACK:
97                 if (unset)
98                         return (*opt->callback)(opt, NULL, 1);
99                 if (opt->flags & PARSE_OPT_NOARG)
100                         return (*opt->callback)(opt, NULL, 0);
101                 if (opt->flags & PARSE_OPT_OPTARG && !p->opt)
102                         return (*opt->callback)(opt, NULL, 0);
103                 if (!arg)
104                         return opterror(opt, "requires a value", flags);
105                 return (*opt->callback)(opt, get_arg(p), 0);
106
107         case OPTION_INTEGER:
108                 if (unset) {
109                         *(int *)opt->value = 0;
110                         return 0;
111                 }
112                 if (opt->flags & PARSE_OPT_OPTARG && !p->opt) {
113                         *(int *)opt->value = opt->defval;
114                         return 0;
115                 }
116                 if (!arg)
117                         return opterror(opt, "requires a value", flags);
118                 *(int *)opt->value = strtol(get_arg(p), (char **)&s, 10);
119                 if (*s)
120                         return opterror(opt, "expects a numerical value", flags);
121                 return 0;
122
123         default:
124                 die("should not happen, someone must be hit on the forehead");
125         }
126 }
127
128 static int parse_short_opt(struct optparse_t *p, const struct option *options)
129 {
130         for (; options->type != OPTION_END; options++) {
131                 if (options->short_name == *p->opt) {
132                         p->opt = p->opt[1] ? p->opt + 1 : NULL;
133                         return get_value(p, options, OPT_SHORT);
134                 }
135         }
136         return error("unknown switch `%c'", *p->opt);
137 }
138
139 static int parse_long_opt(struct optparse_t *p, const char *arg,
140                           const struct option *options)
141 {
142         const char *arg_end = strchr(arg, '=');
143         const struct option *abbrev_option = NULL, *ambiguous_option = NULL;
144         int abbrev_flags = 0, ambiguous_flags = 0;
145
146         if (!arg_end)
147                 arg_end = arg + strlen(arg);
148
149         for (; options->type != OPTION_END; options++) {
150                 const char *rest;
151                 int flags = 0;
152
153                 if (!options->long_name)
154                         continue;
155
156                 rest = skip_prefix(arg, options->long_name);
157                 if (options->type == OPTION_ARGUMENT) {
158                         if (!rest)
159                                 continue;
160                         if (*rest == '=')
161                                 return opterror(options, "takes no value", flags);
162                         if (*rest)
163                                 continue;
164                         p->out[p->cpidx++] = arg - 2;
165                         return 0;
166                 }
167                 if (!rest) {
168                         /* abbreviated? */
169                         if (!strncmp(options->long_name, arg, arg_end - arg)) {
170 is_abbreviated:
171                                 if (abbrev_option) {
172                                         /*
173                                          * If this is abbreviated, it is
174                                          * ambiguous. So when there is no
175                                          * exact match later, we need to
176                                          * error out.
177                                          */
178                                         ambiguous_option = abbrev_option;
179                                         ambiguous_flags = abbrev_flags;
180                                 }
181                                 if (!(flags & OPT_UNSET) && *arg_end)
182                                         p->opt = arg_end + 1;
183                                 abbrev_option = options;
184                                 abbrev_flags = flags;
185                                 continue;
186                         }
187                         /* negated and abbreviated very much? */
188                         if (!prefixcmp("no-", arg)) {
189                                 flags |= OPT_UNSET;
190                                 goto is_abbreviated;
191                         }
192                         /* negated? */
193                         if (strncmp(arg, "no-", 3))
194                                 continue;
195                         flags |= OPT_UNSET;
196                         rest = skip_prefix(arg + 3, options->long_name);
197                         /* abbreviated and negated? */
198                         if (!rest && !prefixcmp(options->long_name, arg + 3))
199                                 goto is_abbreviated;
200                         if (!rest)
201                                 continue;
202                 }
203                 if (*rest) {
204                         if (*rest != '=')
205                                 continue;
206                         p->opt = rest + 1;
207                 }
208                 return get_value(p, options, flags);
209         }
210
211         if (ambiguous_option)
212                 return error("Ambiguous option: %s "
213                         "(could be --%s%s or --%s%s)",
214                         arg,
215                         (ambiguous_flags & OPT_UNSET) ?  "no-" : "",
216                         ambiguous_option->long_name,
217                         (abbrev_flags & OPT_UNSET) ?  "no-" : "",
218                         abbrev_option->long_name);
219         if (abbrev_option)
220                 return get_value(p, abbrev_option, abbrev_flags);
221         return error("unknown option `%s'", arg);
222 }
223
224 void check_typos(const char *arg, const struct option *options)
225 {
226         if (strlen(arg) < 3)
227                 return;
228
229         if (!prefixcmp(arg, "no-")) {
230                 error ("did you mean `--%s` (with two dashes ?)", arg);
231                 exit(129);
232         }
233
234         for (; options->type != OPTION_END; options++) {
235                 if (!options->long_name)
236                         continue;
237                 if (!prefixcmp(options->long_name, arg)) {
238                         error ("did you mean `--%s` (with two dashes ?)", arg);
239                         exit(129);
240                 }
241         }
242 }
243
244 static NORETURN void usage_with_options_internal(const char * const *,
245                                                  const struct option *, int);
246
247 int parse_options(int argc, const char **argv, const struct option *options,
248                   const char * const usagestr[], int flags)
249 {
250         struct optparse_t args = { argv + 1, argv, argc - 1, 0, NULL };
251
252         for (; args.argc; args.argc--, args.argv++) {
253                 const char *arg = args.argv[0];
254
255                 if (*arg != '-' || !arg[1]) {
256                         if (flags & PARSE_OPT_STOP_AT_NON_OPTION)
257                                 break;
258                         args.out[args.cpidx++] = args.argv[0];
259                         continue;
260                 }
261
262                 if (arg[1] != '-') {
263                         args.opt = arg + 1;
264                         if (*args.opt == 'h')
265                                 usage_with_options(usagestr, options);
266                         if (parse_short_opt(&args, options) < 0)
267                                 usage_with_options(usagestr, options);
268                         if (args.opt)
269                                 check_typos(arg + 1, options);
270                         while (args.opt) {
271                                 if (*args.opt == 'h')
272                                         usage_with_options(usagestr, options);
273                                 if (parse_short_opt(&args, options) < 0)
274                                         usage_with_options(usagestr, options);
275                         }
276                         continue;
277                 }
278
279                 if (!arg[2]) { /* "--" */
280                         if (!(flags & PARSE_OPT_KEEP_DASHDASH)) {
281                                 args.argc--;
282                                 args.argv++;
283                         }
284                         break;
285                 }
286
287                 if (!strcmp(arg + 2, "help-all"))
288                         usage_with_options_internal(usagestr, options, 1);
289                 if (!strcmp(arg + 2, "help"))
290                         usage_with_options(usagestr, options);
291                 if (parse_long_opt(&args, arg + 2, options))
292                         usage_with_options(usagestr, options);
293         }
294
295         memmove(args.out + args.cpidx, args.argv, args.argc * sizeof(*args.out));
296         args.out[args.cpidx + args.argc] = NULL;
297         return args.cpidx + args.argc;
298 }
299
300 #define USAGE_OPTS_WIDTH 24
301 #define USAGE_GAP         2
302
303 void usage_with_options_internal(const char * const *usagestr,
304                                  const struct option *opts, int full)
305 {
306         fprintf(stderr, "usage: %s\n", *usagestr++);
307         while (*usagestr && **usagestr)
308                 fprintf(stderr, "   or: %s\n", *usagestr++);
309         while (*usagestr) {
310                 fprintf(stderr, "%s%s\n",
311                                 **usagestr ? "    " : "",
312                                 *usagestr);
313                 usagestr++;
314         }
315
316         if (opts->type != OPTION_GROUP)
317                 fputc('\n', stderr);
318
319         for (; opts->type != OPTION_END; opts++) {
320                 size_t pos;
321                 int pad;
322
323                 if (opts->type == OPTION_GROUP) {
324                         fputc('\n', stderr);
325                         if (*opts->help)
326                                 fprintf(stderr, "%s\n", opts->help);
327                         continue;
328                 }
329                 if (!full && (opts->flags & PARSE_OPT_HIDDEN))
330                         continue;
331
332                 pos = fprintf(stderr, "    ");
333                 if (opts->short_name)
334                         pos += fprintf(stderr, "-%c", opts->short_name);
335                 if (opts->long_name && opts->short_name)
336                         pos += fprintf(stderr, ", ");
337                 if (opts->long_name)
338                         pos += fprintf(stderr, "--%s", opts->long_name);
339
340                 switch (opts->type) {
341                 case OPTION_ARGUMENT:
342                         break;
343                 case OPTION_INTEGER:
344                         if (opts->flags & PARSE_OPT_OPTARG)
345                                 if (opts->long_name)
346                                         pos += fprintf(stderr, "[=<n>]");
347                                 else
348                                         pos += fprintf(stderr, "[<n>]");
349                         else
350                                 pos += fprintf(stderr, " <n>");
351                         break;
352                 case OPTION_CALLBACK:
353                         if (opts->flags & PARSE_OPT_NOARG)
354                                 break;
355                         /* FALLTHROUGH */
356                 case OPTION_STRING:
357                         if (opts->argh) {
358                                 if (opts->flags & PARSE_OPT_OPTARG)
359                                         if (opts->long_name)
360                                                 pos += fprintf(stderr, "[=<%s>]", opts->argh);
361                                         else
362                                                 pos += fprintf(stderr, "[<%s>]", opts->argh);
363                                 else
364                                         pos += fprintf(stderr, " <%s>", opts->argh);
365                         } else {
366                                 if (opts->flags & PARSE_OPT_OPTARG)
367                                         if (opts->long_name)
368                                                 pos += fprintf(stderr, "[=...]");
369                                         else
370                                                 pos += fprintf(stderr, "[...]");
371                                 else
372                                         pos += fprintf(stderr, " ...");
373                         }
374                         break;
375                 default: /* OPTION_{BIT,BOOLEAN,SET_INT,SET_PTR} */
376                         break;
377                 }
378
379                 if (pos <= USAGE_OPTS_WIDTH)
380                         pad = USAGE_OPTS_WIDTH - pos;
381                 else {
382                         fputc('\n', stderr);
383                         pad = USAGE_OPTS_WIDTH;
384                 }
385                 fprintf(stderr, "%*s%s\n", pad + USAGE_GAP, "", opts->help);
386         }
387         fputc('\n', stderr);
388
389         exit(129);
390 }
391
392 void usage_with_options(const char * const *usagestr,
393                         const struct option *opts)
394 {
395         usage_with_options_internal(usagestr, opts, 0);
396 }
397
398 /*----- some often used options -----*/
399 #include "cache.h"
400
401 int parse_opt_abbrev_cb(const struct option *opt, const char *arg, int unset)
402 {
403         int v;
404
405         if (!arg) {
406                 v = unset ? 0 : DEFAULT_ABBREV;
407         } else {
408                 v = strtol(arg, (char **)&arg, 10);
409                 if (*arg)
410                         return opterror(opt, "expects a numerical value", 0);
411                 if (v && v < MINIMUM_ABBREV)
412                         v = MINIMUM_ABBREV;
413                 else if (v > 40)
414                         v = 40;
415         }
416         *(int *)(opt->value) = v;
417         return 0;
418 }
419
420 int parse_opt_approxidate_cb(const struct option *opt, const char *arg,
421                              int unset)
422 {
423         *(unsigned long *)(opt->value) = approxidate(arg);
424         return 0;
425 }