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 "common-cmds.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 void add_cmdname(struct cmdnames *cmds, const char *name, int len)
  16 {
  17         struct cmdname *ent;
  18         FLEX_ALLOC_MEM(ent, name, name, len);
  19         ent->len = len;
  20
  21         ALLOC_GROW(cmds->names, cmds->cnt + 1, cmds->alloc);
  22         cmds->names[cmds->cnt++] = ent;
  23 }
  24
  25 static void clean_cmdnames(struct cmdnames *cmds)
  26 {
  27         int i;
  28         for (i = 0; i < cmds->cnt; ++i)
  29                 free(cmds->names[i]);
  30         free(cmds->names);
  31         cmds->cnt = 0;
  32         cmds->alloc = 0;
  33 }
  34
  35 static int cmdname_compare(const void *a_, const void *b_)
  36 {
  37         struct cmdname *a = *(struct cmdname **)a_;
  38         struct cmdname *b = *(struct cmdname **)b_;
  39         return strcmp(a->name, b->name);
  40 }
  41
  42 static void uniq(struct cmdnames *cmds)
  43 {
  44         int i, j;
  45
  46         if (!cmds->cnt)
  47                 return;
  48
  49         for (i = j = 1; i < cmds->cnt; i++) {
  50                 if (!strcmp(cmds->names[i]->name, cmds->names[j-1]->name))
  51                         free(cmds->names[i]);
  52                 else
  53                         cmds->names[j++] = cmds->names[i];
  54         }
  55
  56         cmds->cnt = j;
  57 }
  58
  59 void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes)
  60 {
  61         int ci, cj, ei;
  62         int cmp;
  63
  64         ci = cj = ei = 0;
  65         while (ci < cmds->cnt && ei < excludes->cnt) {
  66                 cmp = strcmp(cmds->names[ci]->name, excludes->names[ei]->name);
  67                 if (cmp < 0)
  68                         cmds->names[cj++] = cmds->names[ci++];
  69                 else if (cmp == 0) {
  70                         ei++;
  71                         free(cmds->names[ci++]);
  72                 } else if (cmp > 0)
  73                         ei++;
  74         }
  75
  76         while (ci < cmds->cnt)
  77                 cmds->names[cj++] = cmds->names[ci++];
  78
  79         cmds->cnt = cj;
  80 }
  81
  82 static void pretty_print_cmdnames(struct cmdnames *cmds, unsigned int colopts)
  83 {
  84         struct string_list list = STRING_LIST_INIT_NODUP;
  85         struct column_options copts;
  86         int i;
  87
  88         for (i = 0; i < cmds->cnt; i++)
  89                 string_list_append(&list, cmds->names[i]->name);
  90         /*
  91          * always enable column display, we only consult column.*
  92          * about layout strategy and stuff
  93          */
  94         colopts = (colopts & ~COL_ENABLE_MASK) | COL_ENABLED;
  95         memset(&copts, 0, sizeof(copts));
  96         copts.indent = "  ";
  97         copts.padding = 2;
  98         print_columns(&list, colopts, &copts);
  99         string_list_clear(&list, 0);
 100 }
 101
 102 static void list_commands_in_dir(struct cmdnames *cmds,
 103                                          const char *path,
 104                                          const char *prefix)
 105 {
 106         DIR *dir = opendir(path);
 107         struct dirent *de;
 108         struct strbuf buf = STRBUF_INIT;
 109         int len;
 110
 111         if (!dir)
 112                 return;
 113         if (!prefix)
 114                 prefix = "git-";
 115
 116         strbuf_addf(&buf, "%s/", path);
 117         len = buf.len;
 118
 119         while ((de = readdir(dir)) != NULL) {
 120                 const char *ent;
 121                 size_t entlen;
 122
 123                 if (!skip_prefix(de->d_name, prefix, &ent))
 124                         continue;
 125
 126                 strbuf_setlen(&buf, len);
 127                 strbuf_addstr(&buf, de->d_name);
 128                 if (!is_executable(buf.buf))
 129                         continue;
 130
 131                 entlen = strlen(ent);
 132                 strip_suffix(ent, ".exe", &entlen);
 133
 134                 add_cmdname(cmds, ent, entlen);
 135         }
 136         closedir(dir);
 137         strbuf_release(&buf);
 138 }
 139
 140 void load_command_list(const char *prefix,
 141                 struct cmdnames *main_cmds,
 142                 struct cmdnames *other_cmds)
 143 {
 144         const char *env_path = getenv("PATH");
 145         const char *exec_path = git_exec_path();
 146
 147         if (exec_path) {
 148                 list_commands_in_dir(main_cmds, exec_path, prefix);
 149                 QSORT(main_cmds->names, main_cmds->cnt, cmdname_compare);
 150                 uniq(main_cmds);
 151         }
 152
 153         if (env_path) {
 154                 char *paths, *path, *colon;
 155                 path = paths = xstrdup(env_path);
 156                 while (1) {
 157                         if ((colon = strchr(path, PATH_SEP)))
 158                                 *colon = 0;
 159                         if (!exec_path || strcmp(path, exec_path))
 160                                 list_commands_in_dir(other_cmds, path, prefix);
 161
 162                         if (!colon)
 163                                 break;
 164                         path = colon + 1;
 165                 }
 166                 free(paths);
 167
 168                 QSORT(other_cmds->names, other_cmds->cnt, cmdname_compare);
 169                 uniq(other_cmds);
 170         }
 171         exclude_cmds(other_cmds, main_cmds);
 172 }
 173
 174 void list_commands(unsigned int colopts,
 175                    struct cmdnames *main_cmds, struct cmdnames *other_cmds)
 176 {
 177         if (main_cmds->cnt) {
 178                 const char *exec_path = git_exec_path();
 179                 printf_ln(_("available git commands in '%s'"), exec_path);
 180                 putchar('\n');
 181                 pretty_print_cmdnames(main_cmds, colopts);
 182                 putchar('\n');
 183         }
 184
 185         if (other_cmds->cnt) {
 186                 printf_ln(_("git commands available from elsewhere on your $PATH"));
 187                 putchar('\n');
 188                 pretty_print_cmdnames(other_cmds, colopts);
 189                 putchar('\n');
 190         }
 191 }
 192
 193 static int cmd_group_cmp(const void *elem1, const void *elem2)
 194 {
 195         const struct cmdname_help *e1 = elem1;
 196         const struct cmdname_help *e2 = elem2;
 197
 198         if (e1->group < e2->group)
 199                 return -1;
 200         if (e1->group > e2->group)
 201                 return 1;
 202         return strcmp(e1->name, e2->name);
 203 }
 204
 205 void list_common_cmds_help(void)
 206 {
 207         int i, longest = 0;
 208         int current_grp = -1;
 209
 210         for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
 211                 if (longest < strlen(common_cmds[i].name))
 212                         longest = strlen(common_cmds[i].name);
 213         }
 214
 215         QSORT(common_cmds, ARRAY_SIZE(common_cmds), cmd_group_cmp);
 216
 217         puts(_("These are common Git commands used in various situations:"));
 218
 219         for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
 220                 if (common_cmds[i].group != current_grp) {
 221                         printf("\n%s\n", _(common_cmd_groups[common_cmds[i].group]));
 222                         current_grp = common_cmds[i].group;
 223                 }
 224
 225                 printf("   %s   ", common_cmds[i].name);
 226                 mput_char(' ', longest - strlen(common_cmds[i].name));
 227                 puts(_(common_cmds[i].help));
 228         }
 229 }
 230
 231 int is_in_cmdlist(struct cmdnames *c, const char *s)
 232 {
 233         int i;
 234         for (i = 0; i < c->cnt; i++)
 235                 if (!strcmp(s, c->names[i]->name))
 236                         return 1;
 237         return 0;
 238 }
 239
 240 static int autocorrect;
 241 static struct cmdnames aliases;
 242
 243 static int git_unknown_cmd_config(const char *var, const char *value, void *cb)
 244 {
 245         const char *p;
 246
 247         if (!strcmp(var, "help.autocorrect"))
 248                 autocorrect = git_config_int(var,value);
 249         /* Also use aliases for command lookup */
 250         if (skip_prefix(var, "alias.", &p))
 251                 add_cmdname(&aliases, p, strlen(p));
 252
 253         return git_default_config(var, value, cb);
 254 }
 255
 256 static int levenshtein_compare(const void *p1, const void *p2)
 257 {
 258         const struct cmdname *const *c1 = p1, *const *c2 = p2;
 259         const char *s1 = (*c1)->name, *s2 = (*c2)->name;
 260         int l1 = (*c1)->len;
 261         int l2 = (*c2)->len;
 262         return l1 != l2 ? l1 - l2 : strcmp(s1, s2);
 263 }
 264
 265 static void add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
 266 {
 267         int i;
 268         ALLOC_GROW(cmds->names, cmds->cnt + old->cnt, cmds->alloc);
 269
 270         for (i = 0; i < old->cnt; i++)
 271                 cmds->names[cmds->cnt++] = old->names[i];
 272         FREE_AND_NULL(old->names);
 273         old->cnt = 0;
 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         read_early_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."),
 360                            cmd);
 361                 if (autocorrect < 0)
 362                         fprintf_ln(stderr,
 363                                    _("Continuing under the assumption that "
 364                                      "you meant '%s'."),
 365                                    assumed);
 366                 else {
 367                         fprintf_ln(stderr,
 368                                    _("Continuing in %0.1f seconds, "
 369                                      "assuming that you meant '%s'."),
 370                                    (float)autocorrect/10.0, assumed);
 371                         sleep_millisec(autocorrect * 100);
 372                 }
 373                 return assumed;
 374         }
 375
 376         fprintf_ln(stderr, _("git: '%s' is not a git command. See 'git --help'."), cmd);
 377
 378         if (SIMILAR_ENOUGH(best_similarity)) {
 379                 fprintf_ln(stderr,
 380                            Q_("\nThe most similar command is",
 381                               "\nThe most similar commands are",
 382                            n));
 383
 384                 for (i = 0; i < n; i++)
 385                         fprintf(stderr, "\t%s\n", main_cmds.names[i]->name);
 386         }
 387
 388         exit(1);
 389 }
 390
 391 int cmd_version(int argc, const char **argv, const char *prefix)
 392 {
 393         int build_options = 0;
 394         const char * const usage[] = {
 395                 N_("git version [<options>]"),
 396                 NULL
 397         };
 398         struct option options[] = {
 399                 OPT_BOOL(0, "build-options", &build_options,
 400                          "also print build options"),
 401                 OPT_END()
 402         };
 403
 404         argc = parse_options(argc, argv, prefix, options, usage, 0);
 405
 406         /*
 407          * The format of this string should be kept stable for compatibility
 408          * with external projects that rely on the output of "git version".
 409          *
 410          * Always show the version, even if other options are given.
 411          */
 412         printf("git version %s\n", git_version_string);
 413
 414         if (build_options) {
 415                 printf("sizeof-long: %d\n", (int)sizeof(long));
 416                 /* NEEDSWORK: also save and output GIT-BUILD_OPTIONS? */
 417         }
 418         return 0;
 419 }
 420
 421 struct similar_ref_cb {
 422         const char *base_ref;
 423         struct string_list *similar_refs;
 424 };
 425
 426 static int append_similar_ref(const char *refname, const struct object_id *oid,
 427                               int flags, void *cb_data)
 428 {
 429         struct similar_ref_cb *cb = (struct similar_ref_cb *)(cb_data);
 430         char *branch = strrchr(refname, '/') + 1;
 431         const char *remote;
 432
 433         /* A remote branch of the same name is deemed similar */
 434         if (skip_prefix(refname, "refs/remotes/", &remote) &&
 435             !strcmp(branch, cb->base_ref))
 436                 string_list_append(cb->similar_refs, remote);
 437         return 0;
 438 }
 439
 440 static struct string_list guess_refs(const char *ref)
 441 {
 442         struct similar_ref_cb ref_cb;
 443         struct string_list similar_refs = STRING_LIST_INIT_NODUP;
 444
 445         ref_cb.base_ref = ref;
 446         ref_cb.similar_refs = &similar_refs;
 447         for_each_ref(append_similar_ref, &ref_cb);
 448         return similar_refs;
 449 }
 450
 451 void help_unknown_ref(const char *ref, const char *cmd, const char *error)
 452 {
 453         int i;
 454         struct string_list suggested_refs = guess_refs(ref);
 455
 456         fprintf_ln(stderr, _("%s: %s - %s"), cmd, ref, error);
 457
 458         if (suggested_refs.nr > 0) {
 459                 fprintf_ln(stderr,
 460                            Q_("\nDid you mean this?",
 461                               "\nDid you mean one of these?",
 462                               suggested_refs.nr));
 463                 for (i = 0; i < suggested_refs.nr; i++)
 464                         fprintf(stderr, "\t%s\n", suggested_refs.items[i].string);
 465         }
 466
 467         string_list_clear(&suggested_refs, 0);
 468         exit(1);
 469 }