help.c

   1 #include "cache.h"
   2 #include "config.h"
   3 #include "builtin.h"
   4 #include "exec_cmd.h"
   5 #include "run-command.h"
   6 #include "levenshtein.h"
   7 #include "help.h"
   8 #include "command-list.h"
   9 #include "string-list.h"
  10 #include "column.h"
  11 #include "version.h"
  12 #include "refs.h"
  13 #include "parse-options.h"
  14
  15 struct category_description {
  16         uint32_t category;
  17         const char *desc;
  18 };
  19 static uint32_t common_mask =
  20         CAT_init | CAT_worktree | CAT_info |
  21         CAT_history | CAT_remote;
  22 static struct category_description common_categories[] = {
  23         { CAT_init, N_("start a working area (see also: git help tutorial)") },
  24         { CAT_worktree, N_("work on the current change (see also: git help everyday)") },
  25         { CAT_info, N_("examine the history and state (see also: git help revisions)") },
  26         { CAT_history, N_("grow, mark and tweak your common history") },
  27         { CAT_remote, N_("collaborate (see also: git help workflows)") },
  28         { 0, NULL }
  29 };
  30
  31 static const char *drop_prefix(const char *name)
  32 {
  33         const char *new_name;
  34
  35         if (skip_prefix(name, "git-", &new_name))
  36                 return new_name;
  37         return name;
  38
  39 }
  40
  41 static void extract_cmds(struct cmdname_help **p_cmds, uint32_t mask)
  42 {
  43         int i, nr = 0;
  44         struct cmdname_help *cmds;
  45
  46         if (ARRAY_SIZE(command_list) == 0)
  47                 BUG("empty command_list[] is a sign of broken generate-cmdlist.sh");
  48
  49         ALLOC_ARRAY(cmds, ARRAY_SIZE(command_list) + 1);
  50
  51         for (i = 0; i < ARRAY_SIZE(command_list); i++) {
  52                 const struct cmdname_help *cmd = command_list + i;
  53
  54                 if (!(cmd->category & mask))
  55                         continue;
  56
  57                 cmds[nr] = *cmd;
  58                 cmds[nr].name = drop_prefix(cmd->name);
  59
  60                 nr++;
  61         }
  62         cmds[nr].name = NULL;
  63         *p_cmds = cmds;
  64 }
  65
  66 static void print_command_list(const struct cmdname_help *cmds,
  67                                uint32_t mask, int longest)
  68 {
  69         int i;
  70
  71         for (i = 0; cmds[i].name; i++) {
  72                 if (cmds[i].category & mask) {
  73                         printf("   %s   ", cmds[i].name);
  74                         mput_char(' ', longest - strlen(cmds[i].name));
  75                         puts(_(cmds[i].help));
  76                 }
  77         }
  78 }
  79
  80 static int cmd_name_cmp(const void *elem1, const void *elem2)
  81 {
  82         const struct cmdname_help *e1 = elem1;
  83         const struct cmdname_help *e2 = elem2;
  84
  85         return strcmp(e1->name, e2->name);
  86 }
  87
  88 static void print_cmd_by_category(const struct category_description *catdesc)
  89 {
  90         struct cmdname_help *cmds;
  91         int longest = 0;
  92         int i, nr = 0;
  93         uint32_t mask = 0;
  94
  95         for (i = 0; catdesc[i].desc; i++)
  96                 mask |= catdesc[i].category;
  97
  98         extract_cmds(&cmds, mask);
  99
 100         for (i = 0; cmds[i].name; i++, nr++) {
 101                 if (longest < strlen(cmds[i].name))
 102                         longest = strlen(cmds[i].name);
 103         }
 104         QSORT(cmds, nr, cmd_name_cmp);
 105
 106         for (i = 0; catdesc[i].desc; i++) {
 107                 uint32_t mask = catdesc[i].category;
 108                 const char *desc = catdesc[i].desc;
 109
 110                 printf("\n%s\n", _(desc));
 111                 print_command_list(cmds, mask, longest);
 112         }
 113         free(cmds);
 114 }
 115
 116 void add_cmdname(struct cmdnames *cmds, const char *name, int len)
 117 {
 118         struct cmdname *ent;
 119         FLEX_ALLOC_MEM(ent, name, name, len);
 120         ent->len = len;
 121
 122         ALLOC_GROW(cmds->names, cmds->cnt + 1, cmds->alloc);
 123         cmds->names[cmds->cnt++] = ent;
 124 }
 125
 126 static void clean_cmdnames(struct cmdnames *cmds)
 127 {
 128         int i;
 129         for (i = 0; i < cmds->cnt; ++i)
 130                 free(cmds->names[i]);
 131         free(cmds->names);
 132         cmds->cnt = 0;
 133         cmds->alloc = 0;
 134 }
 135
 136 static int cmdname_compare(const void *a_, const void *b_)
 137 {
 138         struct cmdname *a = *(struct cmdname **)a_;
 139         struct cmdname *b = *(struct cmdname **)b_;
 140         return strcmp(a->name, b->name);
 141 }
 142
 143 static void uniq(struct cmdnames *cmds)
 144 {
 145         int i, j;
 146
 147         if (!cmds->cnt)
 148                 return;
 149
 150         for (i = j = 1; i < cmds->cnt; i++) {
 151                 if (!strcmp(cmds->names[i]->name, cmds->names[j-1]->name))
 152                         free(cmds->names[i]);
 153                 else
 154                         cmds->names[j++] = cmds->names[i];
 155         }
 156
 157         cmds->cnt = j;
 158 }
 159
 160 void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes)
 161 {
 162         int ci, cj, ei;
 163         int cmp;
 164
 165         ci = cj = ei = 0;
 166         while (ci < cmds->cnt && ei < excludes->cnt) {
 167                 cmp = strcmp(cmds->names[ci]->name, excludes->names[ei]->name);
 168                 if (cmp < 0)
 169                         cmds->names[cj++] = cmds->names[ci++];
 170                 else if (cmp == 0) {
 171                         ei++;
 172                         free(cmds->names[ci++]);
 173                 } else if (cmp > 0)
 174                         ei++;
 175         }
 176
 177         while (ci < cmds->cnt)
 178                 cmds->names[cj++] = cmds->names[ci++];
 179
 180         cmds->cnt = cj;
 181 }
 182
 183 static void pretty_print_cmdnames(struct cmdnames *cmds, unsigned int colopts)
 184 {
 185         struct string_list list = STRING_LIST_INIT_NODUP;
 186         struct column_options copts;
 187         int i;
 188
 189         for (i = 0; i < cmds->cnt; i++)
 190                 string_list_append(&list, cmds->names[i]->name);
 191         /*
 192          * always enable column display, we only consult column.*
 193          * about layout strategy and stuff
 194          */
 195         colopts = (colopts & ~COL_ENABLE_MASK) | COL_ENABLED;
 196         memset(&copts, 0, sizeof(copts));
 197         copts.indent = "  ";
 198         copts.padding = 2;
 199         print_columns(&list, colopts, &copts);
 200         string_list_clear(&list, 0);
 201 }
 202
 203 static void list_commands_in_dir(struct cmdnames *cmds,
 204                                          const char *path,
 205                                          const char *prefix)
 206 {
 207         DIR *dir = opendir(path);
 208         struct dirent *de;
 209         struct strbuf buf = STRBUF_INIT;
 210         int len;
 211
 212         if (!dir)
 213                 return;
 214         if (!prefix)
 215                 prefix = "git-";
 216
 217         strbuf_addf(&buf, "%s/", path);
 218         len = buf.len;
 219
 220         while ((de = readdir(dir)) != NULL) {
 221                 const char *ent;
 222                 size_t entlen;
 223
 224                 if (!skip_prefix(de->d_name, prefix, &ent))
 225                         continue;
 226
 227                 strbuf_setlen(&buf, len);
 228                 strbuf_addstr(&buf, de->d_name);
 229                 if (!is_executable(buf.buf))
 230                         continue;
 231
 232                 entlen = strlen(ent);
 233                 strip_suffix(ent, ".exe", &entlen);
 234
 235                 add_cmdname(cmds, ent, entlen);
 236         }
 237         closedir(dir);
 238         strbuf_release(&buf);
 239 }
 240
 241 void load_command_list(const char *prefix,
 242                 struct cmdnames *main_cmds,
 243                 struct cmdnames *other_cmds)
 244 {
 245         const char *env_path = getenv("PATH");
 246         const char *exec_path = git_exec_path();
 247
 248         if (exec_path) {
 249                 list_commands_in_dir(main_cmds, exec_path, prefix);
 250                 QSORT(main_cmds->names, main_cmds->cnt, cmdname_compare);
 251                 uniq(main_cmds);
 252         }
 253
 254         if (env_path) {
 255                 char *paths, *path, *colon;
 256                 path = paths = xstrdup(env_path);
 257                 while (1) {
 258                         if ((colon = strchr(path, PATH_SEP)))
 259                                 *colon = 0;
 260                         if (!exec_path || strcmp(path, exec_path))
 261                                 list_commands_in_dir(other_cmds, path, prefix);
 262
 263                         if (!colon)
 264                                 break;
 265                         path = colon + 1;
 266                 }
 267                 free(paths);
 268
 269                 QSORT(other_cmds->names, other_cmds->cnt, cmdname_compare);
 270                 uniq(other_cmds);
 271         }
 272         exclude_cmds(other_cmds, main_cmds);
 273 }
 274
 275 void list_commands(unsigned int colopts,
 276                    struct cmdnames *main_cmds, struct cmdnames *other_cmds)
 277 {
 278         if (main_cmds->cnt) {
 279                 const char *exec_path = git_exec_path();
 280                 printf_ln(_("available git commands in '%s'"), exec_path);
 281                 putchar('\n');
 282                 pretty_print_cmdnames(main_cmds, colopts);
 283                 putchar('\n');
 284         }
 285
 286         if (other_cmds->cnt) {
 287                 printf_ln(_("git commands available from elsewhere on your $PATH"));
 288                 putchar('\n');
 289                 pretty_print_cmdnames(other_cmds, colopts);
 290                 putchar('\n');
 291         }
 292 }
 293
 294 void list_common_cmds_help(void)
 295 {
 296         puts(_("These are common Git commands used in various situations:"));
 297         print_cmd_by_category(common_categories);
 298 }
 299
 300 void list_all_main_cmds(struct string_list *list)
 301 {
 302         struct cmdnames main_cmds, other_cmds;
 303         int i;
 304
 305         memset(&main_cmds, 0, sizeof(main_cmds));
 306         memset(&other_cmds, 0, sizeof(other_cmds));
 307         load_command_list("git-", &main_cmds, &other_cmds);
 308
 309         for (i = 0; i < main_cmds.cnt; i++)
 310                 string_list_append(list, main_cmds.names[i]->name);
 311
 312         clean_cmdnames(&main_cmds);
 313         clean_cmdnames(&other_cmds);
 314 }
 315
 316 void list_all_other_cmds(struct string_list *list)
 317 {
 318         struct cmdnames main_cmds, other_cmds;
 319         int i;
 320
 321         memset(&main_cmds, 0, sizeof(main_cmds));
 322         memset(&other_cmds, 0, sizeof(other_cmds));
 323         load_command_list("git-", &main_cmds, &other_cmds);
 324
 325         for (i = 0; i < other_cmds.cnt; i++)
 326                 string_list_append(list, other_cmds.names[i]->name);
 327
 328         clean_cmdnames(&main_cmds);
 329         clean_cmdnames(&other_cmds);
 330 }
 331
 332 void list_cmds_by_category(struct string_list *list,
 333                            const char *cat)
 334 {
 335         int i, n = ARRAY_SIZE(command_list);
 336         uint32_t cat_id = 0;
 337
 338         for (i = 0; category_names[i]; i++) {
 339                 if (!strcmp(cat, category_names[i])) {
 340                         cat_id = 1UL << i;
 341                         break;
 342                 }
 343         }
 344         if (!cat_id)
 345                 die(_("unsupported command listing type '%s'"), cat);
 346
 347         for (i = 0; i < n; i++) {
 348                 struct cmdname_help *cmd = command_list + i;
 349
 350                 if (cmd->category & cat_id)
 351                         string_list_append(list, drop_prefix(cmd->name));
 352         }
 353 }
 354
 355 int is_in_cmdlist(struct cmdnames *c, const char *s)
 356 {
 357         int i;
 358         for (i = 0; i < c->cnt; i++)
 359                 if (!strcmp(s, c->names[i]->name))
 360                         return 1;
 361         return 0;
 362 }
 363
 364 static int autocorrect;
 365 static struct cmdnames aliases;
 366
 367 static int git_unknown_cmd_config(const char *var, const char *value, void *cb)
 368 {
 369         const char *p;
 370
 371         if (!strcmp(var, "help.autocorrect"))
 372                 autocorrect = git_config_int(var,value);
 373         /* Also use aliases for command lookup */
 374         if (skip_prefix(var, "alias.", &p))
 375                 add_cmdname(&aliases, p, strlen(p));
 376
 377         return git_default_config(var, value, cb);
 378 }
 379
 380 static int levenshtein_compare(const void *p1, const void *p2)
 381 {
 382         const struct cmdname *const *c1 = p1, *const *c2 = p2;
 383         const char *s1 = (*c1)->name, *s2 = (*c2)->name;
 384         int l1 = (*c1)->len;
 385         int l2 = (*c2)->len;
 386         return l1 != l2 ? l1 - l2 : strcmp(s1, s2);
 387 }
 388
 389 static void add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
 390 {
 391         int i;
 392         ALLOC_GROW(cmds->names, cmds->cnt + old->cnt, cmds->alloc);
 393
 394         for (i = 0; i < old->cnt; i++)
 395                 cmds->names[cmds->cnt++] = old->names[i];
 396         FREE_AND_NULL(old->names);
 397         old->cnt = 0;
 398 }
 399
 400 /* An empirically derived magic number */
 401 #define SIMILARITY_FLOOR 7
 402 #define SIMILAR_ENOUGH(x) ((x) < SIMILARITY_FLOOR)
 403
 404 static const char bad_interpreter_advice[] =
 405         N_("'%s' appears to be a git command, but we were not\n"
 406         "able to execute it. Maybe git-%s is broken?");
 407
 408 const char *help_unknown_cmd(const char *cmd)
 409 {
 410         int i, n, best_similarity = 0;
 411         struct cmdnames main_cmds, other_cmds;
 412         struct cmdname_help *common_cmds;
 413
 414         memset(&main_cmds, 0, sizeof(main_cmds));
 415         memset(&other_cmds, 0, sizeof(other_cmds));
 416         memset(&aliases, 0, sizeof(aliases));
 417
 418         read_early_config(git_unknown_cmd_config, NULL);
 419
 420         load_command_list("git-", &main_cmds, &other_cmds);
 421
 422         add_cmd_list(&main_cmds, &aliases);
 423         add_cmd_list(&main_cmds, &other_cmds);
 424         QSORT(main_cmds.names, main_cmds.cnt, cmdname_compare);
 425         uniq(&main_cmds);
 426
 427         extract_cmds(&common_cmds, common_mask);
 428
 429         /* This abuses cmdname->len for levenshtein distance */
 430         for (i = 0, n = 0; i < main_cmds.cnt; i++) {
 431                 int cmp = 0; /* avoid compiler stupidity */
 432                 const char *candidate = main_cmds.names[i]->name;
 433
 434                 /*
 435                  * An exact match means we have the command, but
 436                  * for some reason exec'ing it gave us ENOENT; probably
 437                  * it's a bad interpreter in the #! line.
 438                  */
 439                 if (!strcmp(candidate, cmd))
 440                         die(_(bad_interpreter_advice), cmd, cmd);
 441
 442                 /* Does the candidate appear in common_cmds list? */
 443                 while (common_cmds[n].name &&
 444                        (cmp = strcmp(common_cmds[n].name, candidate)) < 0)
 445                         n++;
 446                 if (common_cmds[n].name && !cmp) {
 447                         /* Yes, this is one of the common commands */
 448                         n++; /* use the entry from common_cmds[] */
 449                         if (starts_with(candidate, cmd)) {
 450                                 /* Give prefix match a very good score */
 451                                 main_cmds.names[i]->len = 0;
 452                                 continue;
 453                         }
 454                 }
 455
 456                 main_cmds.names[i]->len =
 457                         levenshtein(cmd, candidate, 0, 2, 1, 3) + 1;
 458         }
 459         FREE_AND_NULL(common_cmds);
 460
 461         QSORT(main_cmds.names, main_cmds.cnt, levenshtein_compare);
 462
 463         if (!main_cmds.cnt)
 464                 die(_("Uh oh. Your system reports no Git commands at all."));
 465
 466         /* skip and count prefix matches */
 467         for (n = 0; n < main_cmds.cnt && !main_cmds.names[n]->len; n++)
 468                 ; /* still counting */
 469
 470         if (main_cmds.cnt <= n) {
 471                 /* prefix matches with everything? that is too ambiguous */
 472                 best_similarity = SIMILARITY_FLOOR + 1;
 473         } else {
 474                 /* count all the most similar ones */
 475                 for (best_similarity = main_cmds.names[n++]->len;
 476                      (n < main_cmds.cnt &&
 477                       best_similarity == main_cmds.names[n]->len);
 478                      n++)
 479                         ; /* still counting */
 480         }
 481         if (autocorrect && n == 1 && SIMILAR_ENOUGH(best_similarity)) {
 482                 const char *assumed = main_cmds.names[0]->name;
 483                 main_cmds.names[0] = NULL;
 484                 clean_cmdnames(&main_cmds);
 485                 fprintf_ln(stderr,
 486                            _("WARNING: You called a Git command named '%s', "
 487                              "which does not exist."),
 488                            cmd);
 489                 if (autocorrect < 0)
 490                         fprintf_ln(stderr,
 491                                    _("Continuing under the assumption that "
 492                                      "you meant '%s'."),
 493                                    assumed);
 494                 else {
 495                         fprintf_ln(stderr,
 496                                    _("Continuing in %0.1f seconds, "
 497                                      "assuming that you meant '%s'."),
 498                                    (float)autocorrect/10.0, assumed);
 499                         sleep_millisec(autocorrect * 100);
 500                 }
 501                 return assumed;
 502         }
 503
 504         fprintf_ln(stderr, _("git: '%s' is not a git command. See 'git --help'."), cmd);
 505
 506         if (SIMILAR_ENOUGH(best_similarity)) {
 507                 fprintf_ln(stderr,
 508                            Q_("\nThe most similar command is",
 509                               "\nThe most similar commands are",
 510                            n));
 511
 512                 for (i = 0; i < n; i++)
 513                         fprintf(stderr, "\t%s\n", main_cmds.names[i]->name);
 514         }
 515
 516         exit(1);
 517 }
 518
 519 int cmd_version(int argc, const char **argv, const char *prefix)
 520 {
 521         int build_options = 0;
 522         const char * const usage[] = {
 523                 N_("git version [<options>]"),
 524                 NULL
 525         };
 526         struct option options[] = {
 527                 OPT_BOOL(0, "build-options", &build_options,
 528                          "also print build options"),
 529                 OPT_END()
 530         };
 531
 532         argc = parse_options(argc, argv, prefix, options, usage, 0);
 533
 534         /*
 535          * The format of this string should be kept stable for compatibility
 536          * with external projects that rely on the output of "git version".
 537          *
 538          * Always show the version, even if other options are given.
 539          */
 540         printf("git version %s\n", git_version_string);
 541
 542         if (build_options) {
 543                 printf("cpu: %s\n", GIT_HOST_CPU);
 544                 if (git_built_from_commit_string[0])
 545                         printf("built from commit: %s\n",
 546                                git_built_from_commit_string);
 547                 else
 548                         printf("no commit associated with this build\n");
 549                 printf("sizeof-long: %d\n", (int)sizeof(long));
 550                 /* NEEDSWORK: also save and output GIT-BUILD_OPTIONS? */
 551         }
 552         return 0;
 553 }
 554
 555 struct similar_ref_cb {
 556         const char *base_ref;
 557         struct string_list *similar_refs;
 558 };
 559
 560 static int append_similar_ref(const char *refname, const struct object_id *oid,
 561                               int flags, void *cb_data)
 562 {
 563         struct similar_ref_cb *cb = (struct similar_ref_cb *)(cb_data);
 564         char *branch = strrchr(refname, '/') + 1;
 565         const char *remote;
 566
 567         /* A remote branch of the same name is deemed similar */
 568         if (skip_prefix(refname, "refs/remotes/", &remote) &&
 569             !strcmp(branch, cb->base_ref))
 570                 string_list_append(cb->similar_refs, remote);
 571         return 0;
 572 }
 573
 574 static struct string_list guess_refs(const char *ref)
 575 {
 576         struct similar_ref_cb ref_cb;
 577         struct string_list similar_refs = STRING_LIST_INIT_NODUP;
 578
 579         ref_cb.base_ref = ref;
 580         ref_cb.similar_refs = &similar_refs;
 581         for_each_ref(append_similar_ref, &ref_cb);
 582         return similar_refs;
 583 }
 584
 585 void help_unknown_ref(const char *ref, const char *cmd, const char *error)
 586 {
 587         int i;
 588         struct string_list suggested_refs = guess_refs(ref);
 589
 590         fprintf_ln(stderr, _("%s: %s - %s"), cmd, ref, error);
 591
 592         if (suggested_refs.nr > 0) {
 593                 fprintf_ln(stderr,
 594                            Q_("\nDid you mean this?",
 595                               "\nDid you mean one of these?",
 596                               suggested_refs.nr));
 597                 for (i = 0; i < suggested_refs.nr; i++)
 598                         fprintf(stderr, "\t%s\n", suggested_refs.items[i].string);
 599         }
 600
 601         string_list_clear(&suggested_refs, 0);
 602         exit(1);
 603 }