help.c

   1 #include "cache.h"
   2 #include "builtin.h"
   3 #include "exec_cmd.h"
   4 #include "run-command.h"
   5 #include "levenshtein.h"
   6 #include "help.h"
   7 #include "common-cmds.h"
   8 #include "string-list.h"
   9 #include "column.h"
  10 #include "version.h"
  11 #include "refs.h"
  12 #include "parse-options.h"
  13
  14 void add_cmdname(struct cmdnames *cmds, const char *name, int len)
  15 {
  16         struct cmdname *ent;
  17         FLEX_ALLOC_MEM(ent, name, name, len);
  18         ent->len = len;
  19
  20         ALLOC_GROW(cmds->names, cmds->cnt + 1, cmds->alloc);
  21         cmds->names[cmds->cnt++] = ent;
  22 }
  23
  24 static void clean_cmdnames(struct cmdnames *cmds)
  25 {
  26         int i;
  27         for (i = 0; i < cmds->cnt; ++i)
  28                 free(cmds->names[i]);
  29         free(cmds->names);
  30         cmds->cnt = 0;
  31         cmds->alloc = 0;
  32 }
  33
  34 static int cmdname_compare(const void *a_, const void *b_)
  35 {
  36         struct cmdname *a = *(struct cmdname **)a_;
  37         struct cmdname *b = *(struct cmdname **)b_;
  38         return strcmp(a->name, b->name);
  39 }
  40
  41 static void uniq(struct cmdnames *cmds)
  42 {
  43         int i, j;
  44
  45         if (!cmds->cnt)
  46                 return;
  47
  48         for (i = j = 1; i < cmds->cnt; i++) {
  49                 if (!strcmp(cmds->names[i]->name, cmds->names[j-1]->name))
  50                         free(cmds->names[i]);
  51                 else
  52                         cmds->names[j++] = cmds->names[i];
  53         }
  54
  55         cmds->cnt = j;
  56 }
  57
  58 void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes)
  59 {
  60         int ci, cj, ei;
  61         int cmp;
  62
  63         ci = cj = ei = 0;
  64         while (ci < cmds->cnt && ei < excludes->cnt) {
  65                 cmp = strcmp(cmds->names[ci]->name, excludes->names[ei]->name);
  66                 if (cmp < 0)
  67                         cmds->names[cj++] = cmds->names[ci++];
  68                 else if (cmp == 0) {
  69                         ei++;
  70                         free(cmds->names[ci++]);
  71                 } else if (cmp > 0)
  72                         ei++;
  73         }
  74
  75         while (ci < cmds->cnt)
  76                 cmds->names[cj++] = cmds->names[ci++];
  77
  78         cmds->cnt = cj;
  79 }
  80
  81 static void pretty_print_cmdnames(struct cmdnames *cmds, unsigned int colopts)
  82 {
  83         struct string_list list = STRING_LIST_INIT_NODUP;
  84         struct column_options copts;
  85         int i;
  86
  87         for (i = 0; i < cmds->cnt; i++)
  88                 string_list_append(&list, cmds->names[i]->name);
  89         /*
  90          * always enable column display, we only consult column.*
  91          * about layout strategy and stuff
  92          */
  93         colopts = (colopts & ~COL_ENABLE_MASK) | COL_ENABLED;
  94         memset(&copts, 0, sizeof(copts));
  95         copts.indent = "  ";
  96         copts.padding = 2;
  97         print_columns(&list, colopts, &copts);
  98         string_list_clear(&list, 0);
  99 }
 100
 101 static void list_commands_in_dir(struct cmdnames *cmds,
 102                                          const char *path,
 103                                          const char *prefix)
 104 {
 105         DIR *dir = opendir(path);
 106         struct dirent *de;
 107         struct strbuf buf = STRBUF_INIT;
 108         int len;
 109
 110         if (!dir)
 111                 return;
 112         if (!prefix)
 113                 prefix = "git-";
 114
 115         strbuf_addf(&buf, "%s/", path);
 116         len = buf.len;
 117
 118         while ((de = readdir(dir)) != NULL) {
 119                 const char *ent;
 120                 size_t entlen;
 121
 122                 if (!skip_prefix(de->d_name, prefix, &ent))
 123                         continue;
 124
 125                 strbuf_setlen(&buf, len);
 126                 strbuf_addstr(&buf, de->d_name);
 127                 if (!is_executable(buf.buf))
 128                         continue;
 129
 130                 entlen = strlen(ent);
 131                 strip_suffix(ent, ".exe", &entlen);
 132
 133                 add_cmdname(cmds, ent, entlen);
 134         }
 135         closedir(dir);
 136         strbuf_release(&buf);
 137 }
 138
 139 void load_command_list(const char *prefix,
 140                 struct cmdnames *main_cmds,
 141                 struct cmdnames *other_cmds)
 142 {
 143         const char *env_path = getenv("PATH");
 144         const char *exec_path = git_exec_path();
 145
 146         if (exec_path) {
 147                 list_commands_in_dir(main_cmds, exec_path, prefix);
 148                 QSORT(main_cmds->names, main_cmds->cnt, cmdname_compare);
 149                 uniq(main_cmds);
 150         }
 151
 152         if (env_path) {
 153                 char *paths, *path, *colon;
 154                 path = paths = xstrdup(env_path);
 155                 while (1) {
 156                         if ((colon = strchr(path, PATH_SEP)))
 157                                 *colon = 0;
 158                         if (!exec_path || strcmp(path, exec_path))
 159                                 list_commands_in_dir(other_cmds, path, prefix);
 160
 161                         if (!colon)
 162                                 break;
 163                         path = colon + 1;
 164                 }
 165                 free(paths);
 166
 167                 QSORT(other_cmds->names, other_cmds->cnt, cmdname_compare);
 168                 uniq(other_cmds);
 169         }
 170         exclude_cmds(other_cmds, main_cmds);
 171 }
 172
 173 void list_commands(unsigned int colopts,
 174                    struct cmdnames *main_cmds, struct cmdnames *other_cmds)
 175 {
 176         if (main_cmds->cnt) {
 177                 const char *exec_path = git_exec_path();
 178                 printf_ln(_("available git commands in '%s'"), exec_path);
 179                 putchar('\n');
 180                 pretty_print_cmdnames(main_cmds, colopts);
 181                 putchar('\n');
 182         }
 183
 184         if (other_cmds->cnt) {
 185                 printf_ln(_("git commands available from elsewhere on your $PATH"));
 186                 putchar('\n');
 187                 pretty_print_cmdnames(other_cmds, colopts);
 188                 putchar('\n');
 189         }
 190 }
 191
 192 static int cmd_group_cmp(const void *elem1, const void *elem2)
 193 {
 194         const struct cmdname_help *e1 = elem1;
 195         const struct cmdname_help *e2 = elem2;
 196
 197         if (e1->group < e2->group)
 198                 return -1;
 199         if (e1->group > e2->group)
 200                 return 1;
 201         return strcmp(e1->name, e2->name);
 202 }
 203
 204 void list_common_cmds_help(void)
 205 {
 206         int i, longest = 0;
 207         int current_grp = -1;
 208
 209         for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
 210                 if (longest < strlen(common_cmds[i].name))
 211                         longest = strlen(common_cmds[i].name);
 212         }
 213
 214         QSORT(common_cmds, ARRAY_SIZE(common_cmds), cmd_group_cmp);
 215
 216         puts(_("These are common Git commands used in various situations:"));
 217
 218         for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
 219                 if (common_cmds[i].group != current_grp) {
 220                         printf("\n%s\n", _(common_cmd_groups[common_cmds[i].group]));
 221                         current_grp = common_cmds[i].group;
 222                 }
 223
 224                 printf("   %s   ", common_cmds[i].name);
 225                 mput_char(' ', longest - strlen(common_cmds[i].name));
 226                 puts(_(common_cmds[i].help));
 227         }
 228 }
 229
 230 int is_in_cmdlist(struct cmdnames *c, const char *s)
 231 {
 232         int i;
 233         for (i = 0; i < c->cnt; i++)
 234                 if (!strcmp(s, c->names[i]->name))
 235                         return 1;
 236         return 0;
 237 }
 238
 239 static int autocorrect;
 240 static struct cmdnames aliases;
 241
 242 static int git_unknown_cmd_config(const char *var, const char *value, void *cb)
 243 {
 244         const char *p;
 245
 246         if (!strcmp(var, "help.autocorrect"))
 247                 autocorrect = git_config_int(var,value);
 248         /* Also use aliases for command lookup */
 249         if (skip_prefix(var, "alias.", &p))
 250                 add_cmdname(&aliases, p, strlen(p));
 251
 252         return git_default_config(var, value, cb);
 253 }
 254
 255 static int levenshtein_compare(const void *p1, const void *p2)
 256 {
 257         const struct cmdname *const *c1 = p1, *const *c2 = p2;
 258         const char *s1 = (*c1)->name, *s2 = (*c2)->name;
 259         int l1 = (*c1)->len;
 260         int l2 = (*c2)->len;
 261         return l1 != l2 ? l1 - l2 : strcmp(s1, s2);
 262 }
 263
 264 static void add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
 265 {
 266         int i;
 267         ALLOC_GROW(cmds->names, cmds->cnt + old->cnt, cmds->alloc);
 268
 269         for (i = 0; i < old->cnt; i++)
 270                 cmds->names[cmds->cnt++] = old->names[i];
 271         free(old->names);
 272         old->cnt = 0;
 273         old->names = NULL;
 274 }
 275
 276 /* An empirically derived magic number */
 277 #define SIMILARITY_FLOOR 7
 278 #define SIMILAR_ENOUGH(x) ((x) < SIMILARITY_FLOOR)
 279
 280 static const char bad_interpreter_advice[] =
 281         N_("'%s' appears to be a git command, but we were not\n"
 282         "able to execute it. Maybe git-%s is broken?");
 283
 284 const char *help_unknown_cmd(const char *cmd)
 285 {
 286         int i, n, best_similarity = 0;
 287         struct cmdnames main_cmds, other_cmds;
 288
 289         memset(&main_cmds, 0, sizeof(main_cmds));
 290         memset(&other_cmds, 0, sizeof(other_cmds));
 291         memset(&aliases, 0, sizeof(aliases));
 292
 293         git_config(git_unknown_cmd_config, NULL);
 294
 295         load_command_list("git-", &main_cmds, &other_cmds);
 296
 297         add_cmd_list(&main_cmds, &aliases);
 298         add_cmd_list(&main_cmds, &other_cmds);
 299         QSORT(main_cmds.names, main_cmds.cnt, cmdname_compare);
 300         uniq(&main_cmds);
 301
 302         /* This abuses cmdname->len for levenshtein distance */
 303         for (i = 0, n = 0; i < main_cmds.cnt; i++) {
 304                 int cmp = 0; /* avoid compiler stupidity */
 305                 const char *candidate = main_cmds.names[i]->name;
 306
 307                 /*
 308                  * An exact match means we have the command, but
 309                  * for some reason exec'ing it gave us ENOENT; probably
 310                  * it's a bad interpreter in the #! line.
 311                  */
 312                 if (!strcmp(candidate, cmd))
 313                         die(_(bad_interpreter_advice), cmd, cmd);
 314
 315                 /* Does the candidate appear in common_cmds list? */
 316                 while (n < ARRAY_SIZE(common_cmds) &&
 317                        (cmp = strcmp(common_cmds[n].name, candidate)) < 0)
 318                         n++;
 319                 if ((n < ARRAY_SIZE(common_cmds)) && !cmp) {
 320                         /* Yes, this is one of the common commands */
 321                         n++; /* use the entry from common_cmds[] */
 322                         if (starts_with(candidate, cmd)) {
 323                                 /* Give prefix match a very good score */
 324                                 main_cmds.names[i]->len = 0;
 325                                 continue;
 326                         }
 327                 }
 328
 329                 main_cmds.names[i]->len =
 330                         levenshtein(cmd, candidate, 0, 2, 1, 3) + 1;
 331         }
 332
 333         QSORT(main_cmds.names, main_cmds.cnt, levenshtein_compare);
 334
 335         if (!main_cmds.cnt)
 336                 die(_("Uh oh. Your system reports no Git commands at all."));
 337
 338         /* skip and count prefix matches */
 339         for (n = 0; n < main_cmds.cnt && !main_cmds.names[n]->len; n++)
 340                 ; /* still counting */
 341
 342         if (main_cmds.cnt <= n) {
 343                 /* prefix matches with everything? that is too ambiguous */
 344                 best_similarity = SIMILARITY_FLOOR + 1;
 345         } else {
 346                 /* count all the most similar ones */
 347                 for (best_similarity = main_cmds.names[n++]->len;
 348                      (n < main_cmds.cnt &&
 349                       best_similarity == main_cmds.names[n]->len);
 350                      n++)
 351                         ; /* still counting */
 352         }
 353         if (autocorrect && n == 1 && SIMILAR_ENOUGH(best_similarity)) {
 354                 const char *assumed = main_cmds.names[0]->name;
 355                 main_cmds.names[0] = NULL;
 356                 clean_cmdnames(&main_cmds);
 357                 fprintf_ln(stderr,
 358                            _("WARNING: You called a Git command named '%s', "
 359                              "which does not exist.\n"
 360                              "Continuing under the assumption that you meant '%s'"),
 361                         cmd, assumed);
 362                 if (autocorrect > 0) {
 363                         fprintf_ln(stderr, _("in %0.1f seconds automatically..."),
 364                                 (float)autocorrect/10.0);
 365                         sleep_millisec(autocorrect * 100);
 366                 }
 367                 return assumed;
 368         }
 369
 370         fprintf_ln(stderr, _("git: '%s' is not a git command. See 'git --help'."), cmd);
 371
 372         if (SIMILAR_ENOUGH(best_similarity)) {
 373                 fprintf_ln(stderr,
 374                            Q_("\nThe most similar command is",
 375                               "\nThe most similar commands are",
 376                            n));
 377
 378                 for (i = 0; i < n; i++)
 379                         fprintf(stderr, "\t%s\n", main_cmds.names[i]->name);
 380         }
 381
 382         exit(1);
 383 }
 384
 385 int cmd_version(int argc, const char **argv, const char *prefix)
 386 {
 387         int build_options = 0;
 388         const char * const usage[] = {
 389                 N_("git version [<options>]"),
 390                 NULL
 391         };
 392         struct option options[] = {
 393                 OPT_BOOL(0, "build-options", &build_options,
 394                          "also print build options"),
 395                 OPT_END()
 396         };
 397
 398         argc = parse_options(argc, argv, prefix, options, usage, 0);
 399
 400         /*
 401          * The format of this string should be kept stable for compatibility
 402          * with external projects that rely on the output of "git version".
 403          *
 404          * Always show the version, even if other options are given.
 405          */
 406         printf("git version %s\n", git_version_string);
 407
 408         if (build_options) {
 409                 printf("sizeof-long: %d\n", (int)sizeof(long));
 410                 /* NEEDSWORK: also save and output GIT-BUILD_OPTIONS? */
 411         }
 412         return 0;
 413 }
 414
 415 struct similar_ref_cb {
 416         const char *base_ref;
 417         struct string_list *similar_refs;
 418 };
 419
 420 static int append_similar_ref(const char *refname, const struct object_id *oid,
 421                               int flags, void *cb_data)
 422 {
 423         struct similar_ref_cb *cb = (struct similar_ref_cb *)(cb_data);
 424         char *branch = strrchr(refname, '/') + 1;
 425         const char *remote;
 426
 427         /* A remote branch of the same name is deemed similar */
 428         if (skip_prefix(refname, "refs/remotes/", &remote) &&
 429             !strcmp(branch, cb->base_ref))
 430                 string_list_append(cb->similar_refs, remote);
 431         return 0;
 432 }
 433
 434 static struct string_list guess_refs(const char *ref)
 435 {
 436         struct similar_ref_cb ref_cb;
 437         struct string_list similar_refs = STRING_LIST_INIT_NODUP;
 438
 439         ref_cb.base_ref = ref;
 440         ref_cb.similar_refs = &similar_refs;
 441         for_each_ref(append_similar_ref, &ref_cb);
 442         return similar_refs;
 443 }
 444
 445 void help_unknown_ref(const char *ref, const char *cmd, const char *error)
 446 {
 447         int i;
 448         struct string_list suggested_refs = guess_refs(ref);
 449
 450         fprintf_ln(stderr, _("%s: %s - %s"), cmd, ref, error);
 451
 452         if (suggested_refs.nr > 0) {
 453                 fprintf_ln(stderr,
 454                            Q_("\nDid you mean this?",
 455                               "\nDid you mean one of these?",
 456                               suggested_refs.nr));
 457                 for (i = 0; i < suggested_refs.nr; i++)
 458                         fprintf(stderr, "\t%s\n", suggested_refs.items[i].string);
 459         }
 460
 461         string_list_clear(&suggested_refs, 0);
 462         exit(1);
 463 }