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